Grading sacroiliitis with emphasis on MRI imaging; Grading der Sakroiliitis mit Betonung der MRT-Bildgebung

Energy Technology Data Exchange (ETDEWEB)

Jurik, A.G.; Egund, N. [The Department of Radiology R, Aarhus Kommunehospital (Denmark)

2004-03-01

Cross-sectional imaging techniques play a decisive role in identification, localization, and characterization of alterations in the sacroiliac joint during the early stage of seronegative spondylarthropathy (SpA). Although several studies showed that the diagnostic capabilities of MRI and CT are superior to those of conventional radiography, they have not yet become established and accepted as methods for evaluating the grade of ankylosing spondylitis (AS) in contrast to conventional radiography. The lack of acceptance for MRI and/or CT methods for evaluating and grading changes in the sacroiliac joint makes it difficult to include the results of these procedures in classifying the grade of SpA. Moreover, grading the changes in the sacroiliac joint in SpA with a method more sensitive than conventional radiography will be of prime importance in assessing treatment, e.g., the efficacy of new biological therapeutic agents directed against the tumor necrosis factor-alpha (TNF-{alpha}). An overview of the available grading methods is provided and MRI and CT techniques are presented. (orig.) [German] Schnittbildverfahren spielen bei der Identifizierung, Lokalisation und Charakterisierung von Veraenderungen des Sakroiliakalgelenks (SIG) im Fruehstadium der seronegativen Spondylarthropathie (SpA) eine entscheidende Rolle. Obwohl mehrere Studien zeigten, dass der diagnostische Wert der MRT und CT jenem der konventionellen Radiographie ueberlegen ist, hat sich das Schnittbildverfahren als Mittel zur Evaluierung des Grades der ankylosierenden Spondylitis (AS) im Gegensatz zur konventionellen Radiographie noch nicht etabliert und durchgesetzt. Dieses Fehlen eines akzeptierten MRT- und/oder CT-Verfahrens zur Evaluierung und zum Grading der Veraenderungen am SIG macht es schwierig, die Ergebnisse dieser Verfahren bei der Einstufung des Grades der AS-Veraenderungen und Erarbeitung von Diagnosekriterien fuer andere Formen der SpA einzubeziehen. Ausserdem wird das Grading der SIG

MRI for therapy control in patients with aortic isthmus stenosis; MRT zur Therapiekontrolle bei Patienten mit Aortenisthmusstenose

Energy Technology Data Exchange (ETDEWEB)

Wintersperger, B.J. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Toronto General Hospital, University of Toronto, Department of Medical Imaging, University Health Network, Toronto M5G 2N2 (Canada); Theisen, D.; Reiser, M.F. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany)

2011-01-15

Aortic isthmus stenosis is the most common congenital aortic anomaly and is often a problem for therapy surveillance. In addition to possible comorbidities (e.g. bicuspid aortic valve) it is accompanied by various middle and long-term complications depending on the primary choice of the therapeutic procedure. Magnetic resonance imaging (MRI) plays an important role for the mostly young patients in the control of the aortic isthmus stenosis and therapy because it is non-invasive and there is no X-ray exposure. Radiologists should be well-informed on the principles of the therapeutic procedure in order to be competent in the interpretation of MRI findings. Due to the continuous development of MRI technology, techniques for functional evaluation (e.g. dynamic MRA, 4D PC flow measurement) are increasingly becoming available in addition to high-resolution MR angiography (MRA), which could predict the risk of possible complications, such as aneurysms. However, in this aspect further studies are necessary. Interventional therapy with stents and stent grafts is often employed for the therapy of possible complications following an operation (aneurysms, restenosis) but because of massive metal artefacts the use of MRI is often sometimes severely limited. (orig.) [German] Die Aortenisthmusstenose als haeufigste angeborene Aortenanomalie stellt ein haeufiges Problem der Therapieueberwachung dar und ist neben moeglichen begleitenden Anomalien (z. B. bikuspidale Aortenklappe) in Abhaengigkeit vom primaer gewaehlten Therapieverfahren mit verschiedenen Komplikationen im mittel- bis laengerfristigem Verlauf vergesellschaftet. Bei der Kontrolle der Aortenisthmusstenose bzw. deren Therapie spielt die Magnetresonanztomographie (MRT) aufgrund der Nichtinvasivitaet und fehlenden Strahlenexposition bei den meist juengeren Patienten eine wichtige Rolle. Der Radiologe sollte ueber die Grundzuege der Therapieverfahren informiert sein, um die MRT-Befunde kompetent zu befunden. Durch stetige

Functional MRT in psychiatry and neurology; Funktionelle MRT in Psychiatrie und Neurologie

Energy Technology Data Exchange (ETDEWEB)

Schneider, F. [Universitaetsklinikum der RWTH Aachen (Germany). Klinik fuer Psychiatrie und Psychotherapie; Fink, G.R. (eds.) [Koeln Univ. (Germany). Klinik und Poliklinik fuer Neurologie

2007-07-01

Almost no other method has reach such an interest as the functional imaging in psychiatric and neurological science; it is fascinating to observe the brain at work. The fundamentals of functional magnetic resonance tomography (fMRT) and the interpretation of MRT images are explained; the state-of-the-art is discussed. The book is focussed on the functional imaging within psychiatry and neurology. The book contains 45 contributions within the following chapters: fundamentals, higher brain accomplishments, disease pattern, examinatory examples, perspectives.

The prognostic value of quantified MRI at an early stage of Bell's palsy; Der prognostische Wert der dynamischen, kontrastmittelverstaerkten Region-of-Interest-MRT in der Akutphase der idiopathischen Fazialisparese

Energy Technology Data Exchange (ETDEWEB)

Kress, B.P.J.; Efinger, K.; Gottschalk, A.; Nissen, S.; Solbach, T.; Baehren, W. [Abt. fuer Radiologie, Bundeswehrkrankenhaus Ulm (Germany); Griesbeck, F.; Goriup, A.; Kornhuber, A.W. [Abt. fuer Neurologie und Psychiatrie, Bundeswehrkrankenhaus Ulm (Germany)

2002-04-01

DTPA/kg Koerpergewicht. Der Signalintensitaetsanstieg wurde quantitativ mittels Region of interest (ROI) evaluiert. Die Ergebnisse wurden mit dem klinischen Verlauf und den Resultaten der Elektrophysiologie verglichen. Ergebnisse: Alle 30 Patienten konnten quantitativ ausgewertet werden. Die drei Patienten, die im Verlauf eine chronische Fazialisparese entwickelt haben, wurden mit der MRT am Aufnahmetag erfasst. Die Patienten, die in der MRT Zeichen fuer einen unguenstigen Verlauf zeigten, wiesen in der Elektronenphysiologie ein hochpathologisches Muskelsummenaktionspotenzial auf. Statt mit komplizierten Messalgorithmen liess sich mittels einer einmaligen Messung im inneren Gehoergang eine ausreichend verlaessliche prognostische Aussage machen. Zusammenfassung: Die Region-of-interest-MRT hat zu einem fruehen Zeitpunkt der Erkrankung eine zuverlaessige prognostische Bedeutung. Mit einer im klinischen Alltag einfach durchfuehrbaren quantitativen Messung kann die Prognose in einem Stadium abgeschaetzt werden, an dem eine kausale Therapie noch moeglich ist. (orig.)

Superconducting MRI system, MRT-50A

International Nuclear Information System (INIS)

Sugimoto, Hiroshi; Asahina, Kiyotaka

1987-01-01

The writers' developmental work on MRI (magnetic resonance imaging) was started in 1983. The model used first was MRT-15A (0.15 T). The next model was MRT-22A (0.22 T) which had a magnetic self-shield. As for the development of superconducting MRI system, they started clinical evaluation at Toshiba Central Hospital MRI Center in 1984 and got the official approval in 1985. For the model, use was made of MRT-50A (0.5 T) employing a superconducting magnet made by Toshiba. Herein represented are the basis of the images obtained through MRT-50 and the fact that the application fields of MRI are going on increasing (not only to brain and spine areas but also to the areas of the chest, abdomen and joints), and also the results of the work-in-progress of application software. (author)

Cine MRI of the temporomandibular joint in comparison to static MRI and axiography; Cine-MRT des Kiefergelenks im Vergleich zur konventionellen MRT und Achsiographie

Energy Technology Data Exchange (ETDEWEB)

Beer, A.; Rummeny, E.J. [Inst. fuer Roentgendiagnostik der Technischen Univ. Muenchen, Klinikum rechts der Isar (Germany); Kolk, A.; Neff, A. [Klinik und Poliklinik fuer Mund-Kiefer-Gesichtschirurgie der Technischen Univ. Muenchen, Klinikum rechts der Isar (Germany); Hof, N. [Abt. fuer Diagnostische und Interventionelle Radiologie/Nuklearmedizin, Krankenhaus Dritter Orden, Muenchen-Nymphenburg (Germany); Treumann, T. [Roentgeninstitut, Kantonshospital Luzern (Switzerland)

2004-04-01

Purpose: To evaluate Cine MRI (cMRI) of the temporomandibular joint in comparison to static MRI (sMRI) and axiography. Materials and Methods: In a prospective study with 57 healthy volunteers as well as 33 patients after temporomandibular joint (TMJ) surgery or with severe joint dysfunction, we measured the mobility of both condyle and disc as well as the sagittal angle of condylar inclination with sMRI and cMRI. Measurements and image analysis were performed by a radiologist and a maxillofacial surgeon in consensus. The results of axiography served as standard of reference. Result: Concerning the assessment of the discoligamentous complex, sMRI was superior to cMRI in the patient-group (sensitivity sMRI 85%, cMRI 76%), while no significant difference was found in the volunteer-group (sensitivity sMRI 97.4%, cMRI 98.3%). The results of cMRI and sMRI showed a highly significant correlation with each other, as well as with the axiographic reference tracings (r=0.90). The average mobility of the disc and condyle was 6% and 10% higher in sMRI compared to cMRI (p=0.001) and showed a slightly higher variance (0.043 vs. 0.038). Concerning the condylar inclination angle, both MRI-procedures had the best correlation (r=0.94) with each other and axiography. Conclusion: Real-time MRI of the TMJ is comparable to axiography in its accuracy and is a useful adjunct to conventional static MRI. (orig.) [German] Fragestellung: Evaluation der Cine-MRT (cMRT) des Kiefergelenks im Vergleich zur statischen MRT (sMRT) und Achsiographie. Material und Methode: Bei 57 Probanden und bei 33 Patienten nach operativem Gelenkeingriff oder mit klinischer Funktionsstoerung wurden die Kondylus- und Diskusmobilitaet sowie die horizontale Kondylenbahnneigung (HKN) in der sMRT und in der cMRT bestimmt. Die Auswertung erfolgte durch einen Radiologen und einen Mund-Kiefer-Gesichtschirurgen im Konsensus. Die Werte der Achsiographie dienten als Goldstandard. Ergebnisse: Bezueglich der Abgrenzbarkeit des

Functional MRT in psychiatry and neurology. 2. rev. and upd. ed.; Funktionelle MRT in Psychiatrie und Neurologie

Energy Technology Data Exchange (ETDEWEB)

Schneider, Frank [Universitaetsklinikum Aachen (Germany); Fink, Gereon R. (eds.) [Forschungszentrum Juelich GmbH (Germany); Uniklinik Koeln (Germany)

2013-08-01

The book on functional MRT in psychiatry and neurology covers the following topics: (I) Fundamentals: functional neuro-anatomy, fundamentals of NMR imaging, basic research on the clinical use for diagnostics and therapy; basics of morphometry; real-time fMRT, planning and execution of experimental paradigms; data analysis and statistics; reliability and quality of fMRT experiments; eye movement, neuropharmacologic functional imaging, gender dependent effects, age dependent effects, resting state fMRT; meta analyses. (II) Higher brain achievements: movement and action, perception and attention, visual system and object processing, auditory system, executive functions, somatosensoric system, memory, learning and gratification system, functional neuro-anatomy of speech, number processing and calculation, connectivity, social cognition, emotions, olfactory system, functional imaging in the pain research. (III) Disease pattern: dystonia, Parkinson syndrome, Chorea Huntington, aphasia, apraxia, neglect, amnesia, function recovery following apoplexy, schizophrenia, affective disturbances, anxiety and fear, post-traumatic disturbances, hyperactivity syndrome, personality disorder. (IV) Working tools: brain atlas, tool for integrated analyses of structure, functionality and connectivity (SPM anatomy toolbox).

Magnetic resonance tomography (MRT) for lesions of the temporal lobes

International Nuclear Information System (INIS)

Schoerner, W.; Felix, R.; Meencke, H.J.; Freie Univ. Berlin; Freie Univ. Berlin

1985-01-01

A comparative study between magnetic resonance tomography (MRT) and CT was carried out in 16 patients with temporal lobe epilepsy. The MRT studies were performed on a 0.35 T Magnetom with T.1 modes in a coronal plane. MRT proved to the superior to CT. CT demonstrated a discrete temporal lobe lesion in three patients and MRT in four patients. In addition, unilateral atrophy of the temporal lobe was demonstrated by MRT in six cases; these could not be diagnosed by CT. The lack of artifacts near the skull base, the possibility of producing coronal sections and the excellent tissue differential of MRT provide the basis for improved diagnosis of lesions in the temporal lobes. (orig.) [de

Preoperative assessment of asymptomatic adnexal masses by positron emission tomography and F-18-fluorodeoxyglucose; Praeoperative Dignitaetsbeurteilung asymptomatischer Adnextumoren mittels Positronen-Emissions-Tomographie und F-18-Fluordeoxyglukose

Energy Technology Data Exchange (ETDEWEB)

Fenchel, S.; Kotzerke, J.; Reske, S.N. [Ulm Univ. (Germany). Abt. Nuklearmedizin; Stoehr, I.; Grab, D.; Kreienberg, R. [Ulm Univ. (Germany). Frauenklinik; Nuessle, K.; Rieber, A.; Brambs, H.J. [Ulm Univ. (Germany). Abt. Radiologie 1 (Roentgendiagnostik)

1999-08-01

Aim: To evaluate use of F-18-FDG-PET in assessment of dignity of asymptomatic adnexal masses. Methods: 85 asymptomatic patients with suspicious, asymptomatic adnexal masses were evaluated. Static FDG-PET (Exact HR+ or ECAT 931) imaging of the abdomen was performed following application of 222-555 MBq F-18-FDG. Iterative reconstruction was applied. PET data were analysed visually, at first without and second together with MRT images. Final diagnosis was made by histopathology. Results: FDG-PET allowed correct identification of 4 of 8 malignant adnexal tumors. False negative results were obtained in 2 adenocarcinomas stage pT1a and 2 borderline-tumors. In 60 out of 77 benign adnexal masses malignancy could be excluded. False positive FDG-uptake, partly because of misinterpretation of gastrointestinal activity, was found in 3 inflammatory processes, 1 teratoma, 1 benign schwannoma, 1 dermoid cyst, 1 benign thecoma, 1 serous cyst, 1 serous cystadenoma, 2 mucinous cystadenomas, 2 corpus luteum cysts, 3 endometriosic cysts and 1 sactosalpinx. The overall sensitivity and specifity of FDG-PET alone were 50% and 78%. Evaluation together with MRT images showed a sensitivity of 50% and a specifity of 86%. (orig.) [Deutsch] Ziel: Es wurde untersucht, ob die FDG-PET zu einer Verbesserung der Dignitaetsbeurteilung asymptomatischer, sonographisch malignomsuspekter Ovarialtumoren beitragen kann. Methode: 85 Patientinnen mit malignomsuspekten, asymptomatischen Adnextumoren unterzogen sich einer FDG-PET Untersuchung. Emissionsaufnahmen des Abdomens wurden ca. 1 h nach i.v. Injektion von 222-555 MBq F-18-FDG angefertigt (Exact HR + bzw. ECAT 931). Die Bildrekonstruktion erfolgte iterativ. Die PET-Aufnahmen wurden visuell ausgewertet, zum einen ohne andere bildgebende Verfahren, zum anderen zusammen mit der Kernspintomographie. Die Validierung erfolgte mittels Histologie. Ergebnisse: Histologisch fanden sich 8 Malignome, von denen 4 mittels FDG-PET als richtig positiv erkannt wurden

3D MRI of the colon: methods and first results of 5 patients; 3D-MRT des Kolons: Methodik und erste Ergebnisse

Energy Technology Data Exchange (ETDEWEB)

Luboldt, W; Bauerfeind, P; Pelkonen, P; Steiner, P; Krestin, G P; Debatin, J F [MRI-Zentrum, Dept. Diagnostische Radiologie, Universitaetsspital, Zurich (Switzerland)

1997-09-01

Purpose: `Exoscopic` and endoscopic identification of colorectal pathologies via MRI. Methods: 5 patients (36-88 years), two normal and three with different colorectal pathologies (diverticular disease, polyps and carcinoma of the colon), were examined by MRI after colonoscopy. Subsequent to filling of the colon with a gadolinium-water mixture under MRI-monitoring, 3D-data sets of the colon were acquired in prone and supine positions over a 28 sec breathold interval. Subsequently multiplanar T{sub 1}-weighted 2D-sequences were acquired before and following i.v. administration of Gd-DTPA (0.1 mmol/kg BW). All imaging was performed in the coronal orientation. The 3D-data were interactively analysed based on various displays: Maximum intensity projection (MIP), surface shadowed display (SSD), multiplanar reconstruction (MPR), virtual colonoscopy (VC). Results: All of the colorectal pathologies could be interactively diagnosed by MPR. On MIP images some pathologies were missed. VC presented the morphology of colon haustra as well as of all endoluminally growing lesions in a manner similar to endoscopy. The colon masses showed uptake of contrast media and could thus be differentiated from air or faeces. (orig./AJ) [Deutsch] Ziel: Externe und endoskopische Identifizierung kolorektaler Pathologien mittels MRT. Material und Methoden: 5 Patienten (36-88 Jahre), zwei mit Normalbefund, drei mit verschiedenen kolorektalen pathologischen Befunden (Divertikulose, Polypen, Karzinom), wurden nach der Kolonoskopie mit der MRT untersucht. Dazu wurde das Kolon unter MR-Sichtkontrolle mit einer Gadolinium-Wasser-Mischung gefuellt und als 3D-Datensatz atemangehalten in Bauch- und Rueckenlage aufgenommen. Anschliessend wurden multiplanare, T{sub 1}-gewichtete 2D-Sequenzen vor und nach i.v. Gd-DTPA-Gabe akquiriert. Die 3D-Datensaetze wurden interaktiv unter Zuhilfenahme verschiedener Darstellungsformen analysiert: Maximale Intensitaetsprojektion (MIP), Oberflaechendarstellung

Magnetic resonance imaging (MRI) of the TMJ: Influence on therapy and inter-observer agreement of two radiologists; Magnetresonanztomographie (MRT) des Kiefergelenkes: Einfluss auf Therapieentscheidung und Uebereinstimmung zweier Auswerter

Energy Technology Data Exchange (ETDEWEB)

Vahlensieck, M.; Okweschokwu, S. [Radiologie Haydnhaus, Bonn (Germany); Greven, M. [Medeco Zahnklinik, Bonn (Germany)

2002-11-01

Uebereinstimmungen wurden mittels kappa-Statistik geprueft. Ergebnisse: In 56% wurde eine Aenderung des Therapieplans nach MRT registriert. Eine messbare Konkordanz in der Auswertung fand sich fuer anteriore Diskusposition (kappa 0,44), transversale Diskusposition (kappa 0,46) und Kondylusstellung (0,45). Eine schlechte Konkordanz fand sich bei Signalveraenderungen des Diskus (kappa 0,14) und der bilaminaeren Zone (0,24), knoechernen Veraenderungen (0,13) und Zusatzbefinden (0,29). Diskussion: Die MRT des Kiefergelenkes hat einen messbaren Einfluss auf das therapeutische Vorgehen bei kraniomandibulaerer Dysfunktion (Internal Derangement). In der MRT-Beurteilung der Kriterien Diskusposition und Kondylusstellung kann von einer validen Reproduzierbarkeit ausgegangen werden. In der Beurteilung der Signalintensitaeten sowie knoecherner Veraenderungen ist mit einer deutlichen Untersucherabhaengigkeit zu rechnen. (orig.)

Neurofunctional MRI at high magnetic fields; Neurofunktionelle MRT bei hohen Feldern

Energy Technology Data Exchange (ETDEWEB)

Speck, O. [Fakultaet fuer Naturwissenschaften, Otto-von-Guericke Universitaet Magdeburg, Abteilung Biomedizinische Magnetresonanz, Institut fuer Experimentelle Physik, Magdeburg (Germany); Leibniz Institut fuer Neurobiologie, Magdeburg (Germany); Deutsches Zentrum fuer Neurodegenerative Erkrankungen (DZNE), Magdeburg (Germany); Center for Behavioral Brain Sciences (CBBS), Magdeburg (Germany); Turner, R. [MPI fuer Kognitions- und Neurowissenschaften, Abteilung Neurophysik, Leipzig (Germany)

2013-05-15

group data without the need for voxel-based congruence. (orig.) [German] fMRT-Untersuchungen sind durch den geringen aktivierungsinduzierten Signalunterschied in ihrer Sensitivitaet limitiert und innerhalb kurzer tolerierbarer Messzeiten ist die raeumliche Aufloesung limitiert. fMRT bei 1,5 und mehr noch bei 3 T ist ein zuverlaessiges Werkzeug in der Neurowissenschaft und fuer klinische Anwendungen, wie etwa die praechirurgische Funktionslokalisierung. Die fMRT-Sensitivitaet steigt stark (mehr als linear) mit hoeherer Magnetfeldstaerke. Dies war seit Jahren einer der Hauptgruende fuer die Entwicklung zu hoeheren Feldern wie etwa 7 T. Der Sensitivitaetsgewinn von 7 gegenueber 3 T ist bei hoher raeumlicher Aufloesung am groessten und die fMRT mit sehr hoher isotroper Submillimeteraufloesung wird moeglich. Bisherige Resultate zeigen, dass die Blood-oxygenation-level-dependent(BOLD)-Lokalisierung deutlich praeziser ist als bislang angenommen. Mittels Hochfeld-fMRT werden nicht nur quantitativ bessere Ergebnisse erzielt, sondern Informationen neuer Qualitaet zugaenglich wie etwa die kolumnare und schichtabhaengige Struktur des Kortex. Somit wird der Weg zu weiteren Informationen, wie etwa die Richtung kortikaler Verbindungen, eroeffnet. Diese Moeglichkeiten bergen jedoch auch neue Herausforderungen. So muessen neue Verfahren zur Prozessierung derart hochaufgeloester Daten entwickelt werden, welche z. B. ohne Glaettung auskommen, um den Informationsgehalt der Daten nicht zu reduzieren. Standardaufloesungen von 2-3 mm sind weiterhin bei 3 T ''gut aufgehoben'' und profitieren von geringeren Signalausloeschungen, weniger Verzerrungen und geringerer Lautstaerke. Zum Erreichen hoechster Aufloesung bei 7 T sind parallele Bildgebung und Verzerrungskorrektur essenziell und ermoeglichen eine gute Uebereinstimmung mit anatomischen Aufnahmen. Die Echozeit sollte bei 7 T auf ca. 20-25 ms angepasst und die Datenauswertung fuer einzelne Probanden oder Patienten ohne

Functional MRT in psychiatry and neurology

International Nuclear Information System (INIS)

Schneider, F.; Fink, G.R.

2007-01-01

Almost no other method has reach such an interest as the functional imaging in psychiatric and neurological science; it is fascinating to observe the brain at work. The fundamentals of functional magnetic resonance tomography (fMRT) and the interpretation of MRT images are explained; the state-of-the-art is discussed. The book is focussed on the functional imaging within psychiatry and neurology. The book contains 45 contributions within the following chapters: fundamentals, higher brain accomplishments, disease pattern, examinatory examples, perspectives

Magnetic resonance tomography (MRT) in bronchial carcinoma

International Nuclear Information System (INIS)

Felix, R.; Bittner, R.; Schoerner, W.; Weiss, T.

1988-01-01

Comparative studies were made of 47 patients suffering from histologically and cytologically confirmed bronchial carcinoma, using CT and MRT respectively. CT examinations were performed before and after intravenous administration of contrast medium, whereas the MR examinations were conducted via EEG-triggered T 1 and T 2 marked SE sequences in the axial and coronary planes. Both methods were assessed in respect of tumour visualisation and documentation of tumour spread. Staging of tumour and lymph nodes yielded largely concurring results for CT and MRT. Exceptions were seen in 7 of 10 patients with malignant involvement of the pericardium and in 3 of 27 patients with lymph node metastases located mediastinally and subcarinally where only MRT showed a positive involvement of the pericardium or lymph nodes (with possible consequences for the staging of the tumour or lymph nodes). Decisive advantages of MRT compared with CT were seen in the identification of infiltration of the aortic-wall, in the differentiation of the poststenotic syndrome, in the visualisation of the thoracic wall infiltration and functional information on blood flow rate in upper venolus obstruction caused by a carcinoma. (orig.) [de

Rheumatoid arthritis of the wrist; Dynamic Gd-DTPA enhanced MRT. Rheumatoide Arthritis des Handgelenkes; Dynamische Gd-DTPA-verstaerkte MRT

Energy Technology Data Exchange (ETDEWEB)

Naegele, M. (Radiologische Universitaetsklinik, Bonn (Germany)); Kunze, V. (Radiologische Universitaetsklinik, Bonn (Germany)); Koch, W. (Orthopaedische Universitaetsklinik, Bonn (Germany)); Bruening, R. (Radiologische Universitaetsklinik, Bonn (Germany)); Seelos, K. (Radiologische Universitaetsklinik, Bonn (Germany)); Stroehmann, I. (Radiologische Universitaetsklinik, Bonn (Germany)); Woell, B. (Radiologische Universitaetsklinik, Bonn (Germany)); Reiser, M. (Radiologische Universitaetsklinik, Bonn (Germany))

1993-02-01

21 patients with rheumatoid arthritis of the wrist diagnosed according to the criteria of the American Rheumatism Association were examined by dynamic MRT before and after the i.v. injection of Gd-DTPA (0.1 mmol/kg). The results were correlated with the clinical and radiological findings. The increased signal intensity of the pannus was 1.17[+-]0.45%/sec and this differed significantly (p<0.001) from bone marrow (0.16[+-]0.11%/sec) and from muscle (0.25[+-]0.16%/sec). Blood sedimentation rate correlated with the gradient of synovial proliferation (p<0.05). There were no further statistically significant correlations between the clinical, radiological and MRT findings and the change in signal intensity from synovial proliferation as shown by dynamic MRT. (orig.)

Fetal magnetic resonance imaging of thoracic and abdominal malformations; Fetale Magnetresonanztomographie thorakaler und abdomineller Malformationen

Energy Technology Data Exchange (ETDEWEB)

Woitek, R.; Asenbaum, U.; Furtner, J.; Prayer, D. [Medizinische Universitaet Wien, Abteilung fuer Neuroradiologie und Muskuloskelettale Radiologie, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria); Brugger, P.C. [Medizinische Universitaet Wien, Zentrum fuer Anatomie und Zellbiologie, Wien (Austria)

2013-02-15

Diagnosis and differential diagnosis of fetal thoracic and abdominal malformations. Ultrasound and magnetic resonance imaging (MRI). In cases of suspected pathologies based on fetal ultrasound MRI can be used for more detailed examinations and can be of assistance in the differential diagnostic process. Improved imaging of anatomical structures and of the composition of different tissues by the use of different MRI sequences. Fetal MRI has become a part of clinical routine in thoracic and abdominal malformations and is the basis for scientific research in this field. In cases of thoracic or abdominal malformations fetal MRI provides important information additional to ultrasound to improve diagnostic accuracy, prognostic evaluation and surgical planning. (orig.) [German] Diagnose und Differenzialdiagnose fetaler thorakaler und abdomineller Malformationen. Ultraschall, MRT. MRT zur weiteren Abklaerung und genaueren Differenzierung bei vielen im Ultraschall gestellten Verdachtsdiagnosen. Verbesserte anatomische Darstellung mittels MRT und Darstellung unterschiedlicher Gewebezusammensetzung mittels verschiedener MR-Sequenzen. Die fetale MRT ist bei der angegebenen Fragestellung in die klinische Routine eingegangen und liefert weiterhin die Basis fuer wissenschaftliche Untersuchungen in diesem Bereich. Die fetale MRT liefert beim Vorliegen thorakaler oder abdomineller Malformationen komplementaer zum Ultraschall wichtige Zusatzinformationen, um die diagnostische Genauigkeit zu erhoehen, die Prognoseabschaetzung zu verbessern und ggf. eine bessere chirurgische Planung zu ermoeglichen. (orig.)

Methodological principles for optimising functional MRI experiments; Methodische Grundlagen der Optimierung funktioneller MR-Experimente

Energy Technology Data Exchange (ETDEWEB)

Wuestenberg, T. [Georg-August-Universitaet Goettingen, Abteilung fuer Medizinische Psychologie (Germany); Georg-August-Universitaet, Abteilung fuer Medizinische Psychologie, Goettingen (Germany); Giesel, F.L. [Deutsches Kebsforschungszentrum (DKFZ) Heidelberg, Abteilung fuer Radiologische Diagnostik (Germany); Strasburger, H. [Georg-August-Universitaet Goettingen, Abteilung fuer Medizinische Psychologie (Germany)

2005-02-01

Functional magnetic resonance imaging (fMRI) is one of the most common methods for localising neuronal activity in the brain. Even though the sensitivity of fMRI is comparatively low, the optimisation of certain experimental parameters allows obtaining reliable results. In this article, approaches for optimising the experimental design, imaging parameters and analytic strategies will be discussed. Clinical neuroscientists and interested physicians will receive practical rules of thumb for improving the efficiency of brain imaging experiments. (orig.) [German] Die funktionelle Magnetresonanztomographie (fMRT) des Zentralnervensystems ist eine der meistgenutzten Methoden zur Lokalisierung neuronaler Aktivitaet im Gehirn. Obwohl die Sensitivitaet der fMRT vergleichsweise gering ist, kann durch die Auswahl geeigneter experimenteller Parameter die Empfindlichkeit dieses bildgebenden Verfahrens gesteigert und die Reliabilitaet der Ergebnisse gewaehrleistet werden. In diesem Artikel werden deshalb Ansaetze fuer die Optimierung des Paradigmendesigns, der MR-Bildgebung und der Datenauswertung diskutiert. Klinischen Forschern und interessierten Aerzten sollen dadurch Richtgroessen fuer die Durchfuehrung effektiver fMRT-Experimente vermittelt werden. (orig.)

LEXIKALISCHE MITTEL IN DER HOTELWERBUNG

OpenAIRE

Blažević, Nevenka

2003-01-01

Werbung ist das wichtigste Marketinginstrument in der Hotellerie. Bei jeder Werbekampagne ist die sprachliche Seite von großer Bedeutung. In diesem Beitrag wird die lexikalische Ebene der Prospekttexte analysiert. Es wird auf allgemeine sprachliche Merkmale dieser Textsorte verwiesen. In Hotelprospekten lassen sich zwei Funktionen erkennen: die Informationsfunktion und die Appellfunktion. Die Appellfunktion wird meistens durch Adjektive ausgedrückt. Bei der Auswahl der lexikalischen Mittel...

Comparison of PET and fMRI activation patterns during declarative memory processes; Vergleich von PET und fMRT-Aktivierungsmustern waehrend deklarativer Gedaechtnisvorgaenge

Energy Technology Data Exchange (ETDEWEB)

Mottaghy, F.M.; Krause, B.J.; Schmidt, D.; Hautzel, H.; Mueller-Gaertner, H.-W. [Heinrich-Heine-Univ. Duesseldorf (Germany). Klinik fuer Nuklearmedizin; Forschungszentrum Juelich (DE). Klinik fuer Nuklearmedizin (KME); Herzog, H.; Shah, N.J. [Forschungszentrum Juelich (DE). Inst. fuer Medizin (IME); Halsband, U. [Albert-Ludwigs-Univ. Freiburg (Germany). Psychologisches Inst., Neuropsychologie

2000-11-01

hochbildhaften Inhaltes zu lernen und dann zu erinnern (visuelle Praesentation). Ergebnisse: Die Gedaechtnisleistung (Anteil der richtigen Assoziationen) der Probanden lag sowohl in der PET- als auch in der fMRT-Studie bei 93%{+-}9,3%. Waehrend des Lernvorgangs wurden sowohl in der PET als auch in der fMRT Aktivierungen im anterioren cingulaeren Kortex, im linken und rechten praefrontalen Kortex und im Praecuneus beobachtet. Nur in der fMRT liess sich waehrend des Lernvorgangs der parahippocampale Kortex mit darstellen. Waehrend der Abfrage zeigten sich Aktivierungen im linken und rechten Praecuneus, im linken praefrontalen Kortex sowie im anterioren cingulaeren Kortex. Unterschiede finden sich hier vor allem im Bereich des praefrontalen Kortex, da in der fMRT frontalpolare Areale aufgrund von Suszeptibilitaetsartefakten nicht darstellbar sind. Die lokalen Maxima der kortikalen Regionen, die in beiden Bildgebungsmodalitaeten darstellbar sind, lagen im Mittel 7,2{+-}6,5 mm auseinander. Schlussfolgerung: Die Gemeinsamkeiten in den Aktivierungsmustern in der PET und der fMRT ueberwiegen. Die Wahl der Bildgebungsmodalitaet fuer eine Aktivierungsstudie sollte u.a. abhaengig vom Design (Einzelsubjekt vs. Gruppenstudie) und untersuchter kortikaler bzw. subkortikaler Struktur (Suszeptabilitaet, Signalaufloesung) getroffen werden. (orig.)

Magnetic resonance tomography (MRT) of the knee joint: Meniscus, cruciate ligaments and hyaline cartilage. Magnetresonanztomographie (MRT) des Kniegelenks: Meniskus, Kreuzbaender und hyaliner Gelenkknorpel

Energy Technology Data Exchange (ETDEWEB)

Hodler, J. (Radiologie, Universitaetsspital, Zurich (Switzerland) Orthopaedische Universitaetsklinik Balgrist, Zurich (Switzerland). Radiologische Abt.); Buess, E. (Orthopaedische Universitaetsklinik Balgrist, Zurich (Switzerland)); Rodriguez, M. (Orthopaedische Universitaetsklinik Balgrist, Zurich (Switzerland)); Imhoff, A. (Orthopaedische Universitaetsklinik Balgrist, Zurich (Switzerland))

1993-08-01

The use of MRT for diagnosing injury to the meniscus, the cruciate ligaments and hyaline cartilage was evaluated retrospectively in 82 knee joints without any knowledge of operative findings. In 49 cases the results were verified by arthroscopy and in 33 cases by arthrotomy. Sensitivity, specificity and diagnostic accuracy of MRT for meniscus lesions was 73.9%, 96.9%, and 94.6%. Corresponding values for lesions of the anterior cruciate ligament were 88.9%, 96.6%, and 94.7%, and for lesions of the hyaline cartilage 62.6%, 96.1%, and 87.9%, respectively. In addition to its high specificity, MRT proved accurate in excluding lesions of the meniscus (97.1%) of the anterior cruciate ligament (96.6%) and of hyaline cartilage (88.8%). A negative finding on MRT therefore makes the presence of a lesion of the meniscus, cruciate ligaments of cartilage unlikely. In such cases one is justified in delaying the use of arthroscopy or arthrotomy. (orig.)

Fetal MRI of pathological brain development; Fetale MRT der pathologischen Hirnentwicklung

Energy Technology Data Exchange (ETDEWEB)

Brugger, P.C. [Medizinische Universitaet Wien (Austria). Arbeitsgruppe Integrative Morphologie, Zentrum fuer Anatomie und Zellbiologie; Prayer, D. [Medizinische Universitaet Wien (Austria). Klinik fuer Radiodiagnostik

2006-02-15

Because of the superior tissue contrast, high spatial resolution, and multiplanar capabilities, fetal magnetic resonance imaging (MRI) can depict fetal brain pathologies with high accuracy. Pathological fetal brain development may result from malformations or acquired conditions. Differentiation of these etiologies is important with respect to managing the actual pregnancy or counseling future pregnancies. As a widened ventricular system is a common hallmark of both maldevelopment and acquired conditions, it may cause problems in the differential diagnosis. Fetal MRI can provide detailed morphological information, which allows refinement of the diagnosis of ventricular enlargement in a large number of cases. Systematic work-up of morphological details that may be recognized on MR images provides an approach for achieving a correct diagnosis in cases of ventricle enlargement. (orig.) [German] Aufgrund des hervorragenden Gewebekontrastes, der hohen raeumlichen Aufloesung und multiplanaren Moeglichkeiten erlaubt die fetale Magnetresonanztomographie (MRT) eine detaillierte Darstellung fetaler Hirnpathologien. Eine pathologische Hirnentwicklung kann sowohl auf Fehlbildungen als auch waehrend der Schwangerschaft erworbenen Stoerungen beruhen. Nachdem die weiteren Konsequenzen fuer die bestehende, aber auch fuer folgende Schwangerschaften zu einem grossen Teil von einer Differenzierung dieser Aetiologien abhaengig sein kann, ist ein Erkennen der jeweiligen Pathologie wesentlich. Die morphologische Praesentation erworbener und fehlbildungsbedingter Veraenderungen auf MR-Bildern ist u. U. sehr aehnlich. Besondere differenzialdiagnostische Probleme bereitet dabei das Vorliegen eines erweiterten Ventrikelsystems, das als Symptom unterschiedlichster Veraenderungen vorliegen kann. Anhand einer systematischen Darstellung mittels MR-erfassbarer morphologischer Details wird eine Anleitung gegeben, bei Bestehen dieses Leitsymptoms zu einer moeglichst genauen Diagnose zu kommen

Speziation von Gadolinium-MRT-Kontrastmitteln in Umweltmatrizes

OpenAIRE

Lindner, Uwe

2017-01-01

Gd-Kontrastmittel werden in der Medizin für die Magnetresonanztomographie (MRT) benötigt, um einen besseren Bildkontrast zu erzielen. Nach der Anwendung gelangen diese Arzneimittel über das Abwasser in die Klärwerke und von dort in die jeweiligen anliegenden Oberflächengewässer. Somit wird es notwendig, den Verbleib der Gd-MRT-Kontrastmittel in der Umwelt zu verfolgen und aufzuklären. In dieser Arbeit werden für die Analyse von Umweltproben Methoden zur Speziesanalytik von Gd-Kontrastmitteln ...

Diagnosis of tumors in the shoulder girdle by means of MRI; Diagnostik von Tumoren des Schulterguertelbereichs in der MRT

Energy Technology Data Exchange (ETDEWEB)

Schlecht, I.; Gaffke, G.; Stroszczynski, C.; Felix, R. [Charite Campus Virchow-Klinikum, Berlin (Germany). Strahlenklinik und Poliklinik

2001-07-01

The aim of the study was to estimate the value of MRI for evaluation of tumors of the shoulder girdle. We diagnosed respectively 13 patients with lesions in the shoulder region. The imaging has been done with a 'Magnetom SP 63' (Siemens, Erlangen, Germany). The protocol consisted of T1- and T2-based SE-sequences in axial slice orientation, T1-based imaging in coronary respectively in sagittal slice orientation as well as T1-based sequences after application of contrast medium. The evaluation of the tumor expansion within the soft tissue was possible. The exact diagnosis in some individual cases - neurinoma, cyst of the synovia - could be found by MRI. Estimation of the dignity in the case of infiltrative growth was possible in most cases. To assess the exact type of tumor was often difficult. Especially the dignity of the cartilaginous tumors could not be precisely described. (orig.) [German] Ziel der Arbeit war es, den Stellenwert der MRT zur Beurteilung von Raumforderungen im Schulterguertelbereich zu evaluieren. Wir konnten retrospektiv 13 Patienten mit Laesionen in der Schulterregion evaluieren. Die Untersuchungen erfolgten an einem 1,5 T supraleitenden Magneten ('Magnetom SP 63', Firma Siemens, Erlangen Deutschland). Das Untersuchungsprotokoll umfasste T1- und T2-gewichtete SE-Sequenzen in axialer Schnittfuehrung und T1-gewichtete Aufnahmen in schraeg koronarer bzw. schraeg sagittaler Schnittfuehrung sowie T1-gewichtete Sequenzen nach Kontrastmittelgabe. Die Beurteilung der Tumorausdehnung in die Weichteile ist mittels der MRT moeglich. Eine Diagnose ist in Einzelfaellen - Neurinom und Synovialzyste - erst mit der Kernspintomographie sicher zu stellen. Ein infiltratives Wachstum laesst sich in der Regel nachweisen, eine Artdiagnose ist jedoch haeufig nicht moeglich. Die Dignitaet konnte insbesondere bei cartilaginaeren Tumoren nicht eindeutig festgelegt werden. (orig.)

MRT of the locomotor system. 4. rev. and enl. ed.; MRT des Bewegungsapparats

Energy Technology Data Exchange (ETDEWEB)

Vahlensieck, Martin [Praxisnetz Radiologie und Nuklearmedizin Bonn Bad Godesberg - RheinSieg, Bonn (Germany); Reiser, Maximilian (ed.) [Klinikum Grosshadern, Muenchen (Germany). Inst. fuer Klinische Radiologie

2015-02-01

The book on MRT of the locomotor system covers the following topics: relevant NMT imaging techniques, spinal cord, shoulder, elbows, wrist and fingers, hip region, knee, lower leg - ankle - foot, temporomandibular joint, skeletal muscles, bone marrow, bone and soft tissue tumors, osteoporosis, sacroiliac joint, jaw and periodontium.

Early alterations in the hip joint following epiphysiolysis for slipped femoral head. Results of an MRI study; Fruehveraenderugen im Hueftgelenk nach Epiphysiolysis capitis femoris. MRT-Untersuchungsergebnisse

Energy Technology Data Exchange (ETDEWEB)

Stoever, B. [Freiburg Univ. (Germany). Radiologische Klinik; Sigmund, G. [Freiburg Univ. (Germany). Radiologische Klinik; Huhle, P. [Freiburg Univ. (Germany). Orthopaedische Abteilung; Zwack, P. [Freiburg Univ. (Germany). Orthopaedische Abteilung; Reichert, A. [Freiburg Univ. (Germany). Orthopaedische Abteilung; Langer, M. [Freiburg Univ. (Germany). Radiologische Klinik

1994-01-01

With the aim of detecting patients at risk of developing coxarthritis, 34 patients were investigated prospectively by MRI 6-14 years after epiphysiolysis for slipped capital femoral head. In particular, cartilage changes were analysed by gradient-echo sequences. In 40% of the hip joints investigated cartilaginous lesions were present, detectable as irregularity and flattening of contour and more rarely as changes in signal intensity. In contrast, only 18% of the radiographs available revealed any pathology. When pelvic X-rays are normal or reveal slight sclerosis, cartilaginous lesions on MRI are considered early signs of coxarthrosis. This combination was seen especially often in patients with a primarily high angle of dislocation and in those who needed treatment by reposition or osteotomy. Only in 8 of the 17 hip joints showing sclerosis on conventional radiograms, sclerosis was also diagnosed by MRI, possibly because of partial volume and susceptibility effects at high field strength. Even with limited spatial resolution, cartilage examinations is warranted in young patients in whom early osteoarthritis can be expected. (orig.) [Deutsch] Mit dem Ziel, Veraenderungen am Hueftgelenk bei Patienten mit Arthroserisiko rechtzeitig zu erfassen, wurden 34 Patienten 6-14 Jahre nach einer Epiphysiolysis capitis femoris mittels MRT im Hochfeld bei 2/T nachuntersucht. Insbesondere sollten anhand der `FLASH`-Gradientenechosequenzen Knorpelveraenderungen analysiert werden. In 40% der untersuchten Hueftgelenke lagen Knorpellaesionen vor, sichtbar als Verduennung der Knorpelschicht, Konturunregelmaessigkeit und seltener als Signalintensitaetsveraenderungen. Dagegen waren nur 18% der vorhandenen Roentgenbefunde eindeutig pathologisch. Die kernspintomographisch sichtbaren Laesionen des Knorpels sind bei normalem Roentgenbild als Fruehveraenderungen zu werten und waren haeufiger bei Patienten mit primaer hohem Dislokationswinkel nachweisbar wie auch bei Patienten, bei denen eine

Cerebral activation studies by PET and fMRT, clinical relevance?; Zerebrale Aktivierungsstudien mit PET und fMRT, klinische Relevanz?

Energy Technology Data Exchange (ETDEWEB)

Brandt, T. [Neurologische Klinik und Poliklinik, Klinikum Grosshadern, Muenchen Univ. (Germany)

1997-03-01

Cerebral activation studies by PET and fMRT will gain increasing clinical relevance for functional neuroanatomy (reading, speaking), localisation of largely unknown cortical functions (vestibular cortex), imaging of subjective complaints of functional impairments (pain, smell, memory), and documentation of neurological rehabilitation at neuronal level (regeneration, compensation, substitution, learning). (orig.) [Deutsch] Zerebrale Aktivierungsstudien mit PET und fMRT erlangen zunehmend klinische Bedeutung fuer die funktionelle Neuroanatomie einzelner und komplexer Hirnleistungen (Lesen, Sprechen), die Lokalisation bislang unzureichend erforschter Hirnfunktionen (vestibulaerer Kortex), die Objektivierung subjektiver Beschwerden und Funktionsausfaelle (Schmerz, Riechen, Gedaechtnis) und die Dokumentation neurologischer Rehabilitation auf neuronaler Ebene (Regeneration, Kompensation, Substitution, Lernen). (orig.)

Image fusion of MRI and fMRI with intraoperative MRI data: methods and clinical relevance for neurosurgical interventions; Fusion von MRT-, fMRT- und intraoperativen MRT-Daten. Methode und klinische Bedeutung am Beispiel neurochirurgischer Interventionen

Energy Technology Data Exchange (ETDEWEB)

Moche, M.; Busse, H.; Dannenberg, C.; Schulz, T.; Schmidt, F.; Kahn, T. [Universitaetsklinikum Leipzig (Germany). Klinik und Poliklinik fuer Diagnostische Radiologie; Schmitgen, A. [GMD Forschungszentrum Informationstechnik GmbH-FIT, Sankt Augustin (Germany); Trantakis, C.; Winkler, D. [Klinik und Poliklinik fuer Neurochirurgie, Universitaetsklinikum Leipzig (Germany)

2001-11-01

The aim of this work was to realize and clinically evaluate an image fusion platform for the integration of preoperative MRI and fMRI data into the intraoperative images of an interventional MRI system with a focus on neurosurgical procedures. A vertically open 0.5 T MRI scanner was equipped with a dedicated navigation system enabling the registration of additional imaging modalities (MRI, fMRI, CT) with the intraoperatively acquired data sets. These merged image data served as the basis for interventional planning and multimodal navigation. So far, the system has been used in 70 neurosurgical interventions (13 of which involved image data fusion - requiring 15 minutes extra time). The augmented navigation system is characterized by a higher frame rate and a higher image quality as compared to the system-integrated navigation based on continuously acquired (near) real time images. Patient movement and tissue shifts can be immediately detected by monitoring the morphological differences between both navigation scenes. The multimodal image fusion allowed a refined navigation planning especially for the resection of deeply seated brain lesions or pathologies close to eloquent areas. Augmented intraoperative orientation and instrument guidance improve the safety and accuracy of neurosurgical interventions. (orig.) [German] Ziel dieser Arbeit waren die Realisierung und klinische Bewertung einer Bildfusion praeoperativer MRT- und fMRT-Bilder mit intraoperativen Datensaetzen eines interventionellen MRT-Systems am Beispiel neurochirurgischer Eingriffe. Ein vertikal offenes 0,5-T-MRT-System wurde mit einem erweiterten Navigationssystem ausgestattet, welches eine Integration zusaetzlicher Bildinformationen (Hochfeld-MRT, fMRT, CT) in die intraoperativ akquirierten Datensaetze erlaubt. Diese fusionierten Bilddaten wurden zur Interventionsplanung und multimodalen Navigation verwendet. Bisher wurde das System bei insgesamt 70 neurochirurgischen Eingriffen eingesetzt, davon 13

Multiparametric and molecular imaging of breast tumors with MRI and PET/MRI; Multiparametrische und molekulare Bildgebung von Brusttumoren mit MRT und PET-MRT

Energy Technology Data Exchange (ETDEWEB)

Pinker, K. [Medizinische Universitaet Wien, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Division fuer Molekulare und Gender Bildgebung, Wien (Austria); Memorial Sloan-Kettering Cancer Center, Department of Radiology, Molecular Imaging and Therapy Service, New York (United States); State University of Florida, Department of Scientific Computing in Medicine, Florida (United States); Marino, M.A. [Medizinische Universitaet Wien, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Division fuer Molekulare und Gender Bildgebung, Wien (Austria); Policlinico Universitario G. Martino, University of Messina, Department of Biomedical Sciences and Morphologic and Functional Imaging, Messina (Italy); Meyer-Baese, A. [State University of Florida, Department of Scientific Computing in Medicine, Florida (United States); Helbich, T.H. [Medizinische Universitaet Wien, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Division fuer Molekulare und Gender Bildgebung, Wien (Austria)

2016-07-15

Magnetic resonance imaging (MRI) of the breast is an indispensable tool in breast imaging for many indications. Several functional parameters with MRI and positron emission tomography (PET) have been assessed for imaging of breast tumors and their combined application is defined as multiparametric imaging. Available data suggest that multiparametric imaging using different functional MRI and PET parameters can provide detailed information about the hallmarks of cancer and may provide additional specificity. Multiparametric and molecular imaging of the breast comprises established MRI parameters, such as dynamic contrast-enhanced MRI, diffusion-weighted imaging (DWI), MR proton spectroscopy ({sup 1}H-MRSI) as well as combinations of radiological and MRI techniques (e.g. PET/CT and PET/MRI) using radiotracers, such as fluorodeoxyglucose (FDG). Multiparametric and molecular imaging of the breast can be performed at different field-strengths (range 1.5-7 T). Emerging parameters comprise novel promising techniques, such as sodium imaging ({sup 23}Na MRI), phosphorus spectroscopy ({sup 31}P-MRSI), chemical exchange saturation transfer (CEST) imaging, blood oxygen level-dependent (BOLD) and hyperpolarized MRI as well as various specific radiotracers. Multiparametric and molecular imaging has multiple applications in breast imaging. Multiparametric and molecular imaging of the breast is an evolving field that will enable improved detection, characterization, staging and monitoring for personalized medicine in breast cancer. (orig.) [German] Die Magnetresonanztomographie (MRT) der Brust ist ein etabliertes nichtinvasives bildgebendes Verfahren mit vielfaeltigen Indikationen. In den letzten Jahren wurden zahlreiche funktionelle MRT- und Positronenemissionstomographie(PET)-Parameter in der Brustbildgebung evaluiert, und ihre kombinierte Anwendung ist als multiparametrische Bildgebung definiert. Bisherige Daten legen nahe, dass die multiparametrische Bildgebung mit MRT und PET

Sentinel-Lymphknoten-Biopsie des Melanoms mittels Indocyaningrün und "FOVIS"-System.

Science.gov (United States)

Göppner, Daniela; Nekwasil, Stephan; Jellestad, Anne; Sachse, Alexander; Schönborn, Karl-Heinz; Gollnick, Harald

2017-02-01

Der Nachweis metastatischer Infiltrate im Sentinel-Lymphkoten (SLN) gilt als wesentlicher prognostischer Faktor des Melanoms. Alternativ zur Farbstoffmethode mit Patentblau zum Goldstandard der SLN-Biopsie (SLNB) mittels Radiokolloid wird die fluoreszenzoptische Darstellung mit Hilfe von Indocyaningrün (ICG) und Nahinfrarot (NIR)-Kamerasystem kommuniziert. Im Vergleich zur konventionellen Methode wurde die Wertigkeit des ICG-/NIR-Verfahrens in Abhängigkeit vom Body-Mass-Index (BMI) des Patienten und der Konzentration von ICG bezüglich der Visualisierung des Lymphabstroms und des SLNs untersucht. An zehn Patienten wurde die SLNB mittels Technetium-99m, Patentblau und ICG durchgeführt. Die Fluoreszenz-Darstellung von Lymphbahnen und SLN erfolgte in Echtzeit mittels der NIR-Kameratechnik "FOVIS". Je nach erzielter Bildqualität wurde ICG in einer Dosis von 0,25 mg bis 2,5 mg intrakutan appliziert. Neun der zehn SLN wurden fluoreszenzoptisch identifiziert (90 %), alle zehn radioaktiv (100 %), nur acht (80 %) mittels ICG-Grünfärbung bzw. Patenblau-Markierung. Transdermal wurde ein SLN dargestellt (10 %). In Korrelation zum BMI waren höhere ICG-Mengen, bis zu 2,5 mg intrakutan absolut, in der Darstellung der Lymphbahnen von Vorteil. Die SLN-Fluoreszenzmarkierung mit dem ICG/NIR-Kamera-System "FOVIS" stellt eine sichere Alternative zur Farbstoffmethode mit Patentblau ergänzend zur Radiokolloidmethode mit Technetium-99m dar. Weitere Studien zur optimalen Dosierung von ICG und transdermalen Bildgebung in Relation zum BMI sind notwendig. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Functional MRT in psychiatry and neurology. 2. rev. and upd. ed.

International Nuclear Information System (INIS)

Schneider, Frank; Fink, Gereon R.

2013-01-01

The book on functional MRT in psychiatry and neurology covers the following topics: (I) Fundamentals: functional neuro-anatomy, fundamentals of NMR imaging, basic research on the clinical use for diagnostics and therapy; basics of morphometry; real-time fMRT, planning and execution of experimental paradigms; data analysis and statistics; reliability and quality of fMRT experiments; eye movement, neuropharmacologic functional imaging, gender dependent effects, age dependent effects, resting state fMRT; meta analyses. (II) Higher brain achievements: movement and action, perception and attention, visual system and object processing, auditory system, executive functions, somatosensoric system, memory, learning and gratification system, functional neuro-anatomy of speech, number processing and calculation, connectivity, social cognition, emotions, olfactory system, functional imaging in the pain research. (III) Disease pattern: dystonia, Parkinson syndrome, Chorea Huntington, aphasia, apraxia, neglect, amnesia, function recovery following apoplexy, schizophrenia, affective disturbances, anxiety and fear, post-traumatic disturbances, hyperactivity syndrome, personality disorder. (IV) Working tools: brain atlas, tool for integrated analyses of structure, functionality and connectivity (SPM anatomy toolbox).

Superconductive MRI system, MRT-50A/SUPER

International Nuclear Information System (INIS)

Suzuki, Hirokazu; Goro, Takehiko

1992-01-01

The MRI (magnetic resonance imaging) market has been rapidly growing and more than 1,300 MRI systems are now operating in the Japanese domestic market. An upper-middle range MRI market, which is characterized by high-image quality, has newly appeared between the high-end and middle-range market niches since last year. To be competitive in this upper-middle range market, Toshiba has developed a superconductive MRI system, the MRT-50A/SUPER. The new system featured a high-performance actively shielded gradient coil called the TSGC (twin-shielded gradient coil), installed in a compact superconductive magnet. This paper introduces the MRT-50A/SUPER and describes recent developments in MRI technology. (author)

MRT of the knee joint of juvenile footballers. Are there early changes in the knee due to competitive sport?; MRT der Kniegelenke jugendlicher Fussballspieler. Gibt es Fruehveraenderungen von Kniebinnenstrukturen durch Leistungssport?

Energy Technology Data Exchange (ETDEWEB)

Wacker, F. [Abt. fuer Radiologische Diagnostik und Nuklearmedizin, Klinikum Steglitz, Freie Univ. Berlin (Germany); Koenig, H. [Abt. fuer Radiologische Diagnostik und Nuklearmedizin, Klinikum Steglitz, Freie Univ. Berlin (Germany); Felsenberg, D. [Abt. fuer Radiologische Diagnostik und Nuklearmedizin, Klinikum Steglitz, Freie Univ. Berlin (Germany); Wolf, K.J. [Abt. fuer Radiologische Diagnostik und Nuklearmedizin, Klinikum Steglitz, Freie Univ. Berlin (Germany)

1994-02-01

In a prospective study, the right knee of 21 symptom free juvenile footballers was examined by MRT (group I) and the results were compared with 12 juveniles of similar age but who did not take part in any special sorting activities (group II). A 1.5 Tesla Magnetome with an extremity coil was used. There were no abnormal changes in either group in the cruciate ligaments. The hyaline cartilage medially was about 10% thicker than laterally in both groups but in group I it was, on average, 24.8% thicker than in group II. Increased signals in the centre of the menisci were observed in 8 members of group I and two in group II. 5 on the 8 in group I, but none in group II, also showed an increase in the joint fluid. (orig.) [Deutsch] In einer retrospektiven Studie wurde das rechte Kniegelenk von 21 beschwerdefreien, jungendlichen Fussballspielern (Gruppe I) sowie von 12 altersgleichen Jungendlichen ohne spezielle sportliche Aktivitaeten (Gruppe II) magnetresonanztomographisch untersucht. Die Messungen erfolgten an einem 1,5-Tesla-Magnetom unter Anwendung einer Extremitaetenspule. Keine pathologischen Veraenderungen ergaben sich bei beiden Gruppen im Bereich der Kreuzbaender. Der hyaline Gelenkknorpel zeigte bei beiden Gruppen am medialen Femurkondylus eine um etwa 10% hoehere Dicke als lateral und erweis sich bei Gruppe I im Mittel um 24,8% dicker als bei Gruppe II. Zentrale Meniskus-Signalvermehrungen konnten bei 8 Jugendlichen der Gruppe I sowie bei zwei der Gruppe II nachgewiesen werden. Dabei wiesen 5/8 der Gruppe I, aber keiner der Gruppe II begleitend eine Gelenkfluessigkeitsvermehrung auf. (orig.)

Cortical blindness after intoxication with heroin; Kortikale Blindheit nach Heroinintoxikation

Energy Technology Data Exchange (ETDEWEB)

Braendli, M. [Institut fuer Diagnostische Radiologie, Universitaetskliniken, Kantonspital Basel (Switzerland); Otte, A.; Mueller-Brand, J. [Institut fuer Nuklearmedizin, Universitaetskliniken, Kantonspital Basel (Switzerland)

2000-07-01

For the case reported, both morphological and functional diagnostic examination methods were applied, such as MRI and CT, or SPECT using ECD as a tracer. The bilateral, occipital lesion finally could be detected with the SPECT examinations, and SPECT findings were clearly better than MRI findings, whereas even restrospective analysis of the CT images failed to show the lesion. Thus the functional imaging method in this case of a discrete bilateral occipital lesion was the most sentitive method. (orig./CB) [German] In unserem Fallbeispiel wurden sowohl morphologische (MRT, CT) als auch funktionelle Bildgebung (SPECT unter Verwendung von ECD als Tracer) ad extensum zur Diagnosefindung verwendet. Die bilaterale okzipitale Defektbildung konnte schliesslich mittels SPECT-Untersuchung deutlich besser dargestellt werden als mittels MRT. In der CT gelangte der Befund - auch bei retrospektiver Betrachtung - ueberhaupt nicht zur Darstellung. Damit war die funktionelle Bildgebung im Falle dieser diskreten bilateralen okzipitalen Defektbildung die sensitivste Methode. (orig.)

Schizophrenia as a disconnection syndrome. Studies with functional magnetic resonance imaging and structural equation modeling; Schizophrenie als Diskonnektionssyndrom. Studien mit funktioneller Magnetresonanztomographie und Strukturgleichungsmodellen

Energy Technology Data Exchange (ETDEWEB)

Schloesser, R. [Universitaet Jena, Psychiatrische Klinik (Germany); Universitaet Jena, Psychiatrische Klinik, Jena (Germany); Wagner, G.; Koehler, S.; Sauer, H. [Universitaet Jena, Psychiatrische Klinik (Germany)

2005-02-01

Aside from characteristic psychopathological symptoms, cognitive deficits are a core feature of schizophrenia. These deficits can only be addressed within the context of widespread functional interactions among different brain areas. To examine these interactions, structural equation modeling (SEM) was used for the analysis of fMRI datasets. In a series of studies, both in antipsychotic-treated and drug-free schizophrenic patients, a pattern of enhanced thalamocortical functional connectivity could be observed as an indicator for possible disruptions of frontostriatal thalamocortical circuitry. Moreover, drug-free patients and those receiving typical antipsychotic drugs were characterized by reduced interhemispheric corticocortical connectivity. This difference relative to normal controls was less in patients under atypical antipsychotic drugs. The results could be interpreted as a beneficial effect of atypical antipsychotic drugs on information processing in schizophrenic patients. The present findings are consistent with the model of schizophrenia as a disconnection syndrome and earlier concepts of ''cognitive dysmetria'' in schizophrenia. (orig.) [German] Neben der charakteristischen psychopathologischen Symptomatik stellen kognitive Defizite ein zentrales Merkmal der Schizophrenie dar. Diese Defizite koennen nur im Kontext miteinander interagierender Hirnareale verstanden werden. Zur Untersuchung dieser funktionellen Wechselbeziehungen wurden Strukturgleichungsmodelle (''structural equation modeling'', SEM) zur Auswertung von fMRT-Datensaetzen verwendet. In einer Untersuchungsreihe bei schizophrenen Patienten ergab sich sowohl bei antipsychotisch behandelten als auch bei unbehandelten Patienten ein Muster gesteigerter thalamokortikaler funktioneller Konnektivitaet als Hinweis auf eine moegliche Stoerung fronto-striato-thalamo-kortikaler Regelkreise. Unbehandelte Patienten und Patienten unter typischen Antipsychotika

Temporomandibular Joint: MRT Diagnostics; Temporomandibulargelenk: MRT-Diagnostik

Energy Technology Data Exchange (ETDEWEB)

Kress, B. [Universitaetsklinikum Heidelberg (Germany). Abteilung Neuroradiologie; Universitaetsklinikum Heidelberg (Germany). Neurologische Klinik; Schmitter, M. [Universitaetsklinikum Heidelberg (Germany). Poliklinik fuer zahnaerztliche Prothetik; Universitaetsklinikum Heidelberg (Germany). Abteilung Neuroradiologie

2005-09-01

MRI of the temporomandibular joint (TMJ) requires 1.5 T. The radiologist must be familiar with the anatomy and pathology of the TMJ. This review gives a description of MRI protocols for the TMJ, and MRI anatomy and pathology of the TMJ (open and closed mouth) by means of MR images and drawings. Diagnosing of the TMJ related diseases depends on standardized clinical and MR examinations. Therefore close interdisciplinary cooperation between dentist and radiologist is necessary. (orig.) [German] Magnetresonanztomographie bei Kiefergelenkbeschwerden erfordert neben guter technischer Ausstattung Kenntnisse der Anatomie und Pathologie des Kiefergelenks. Diese Uebersicht stellt neben MRT-Protokollen die Anatomie und die pathologischen Befunde des Kiefergelenks bei geoeffnetem und geschlossenem Mund anhand von Abbildungen und Graphiken systematisch dar. Bildgebende Diagnostik des Kiefergelenks gruendet sich auf eine standardisierte klinische und magnetresonanztomographische Untersuchung und erfordert eine enge interdisziplinaere Kooperation zwischen Zahnmedizin und Radiologie. (orig.)

Objektverfolgung bei einer vollständigen Fahrzeugumfeldüberwachung mittels Radar

Science.gov (United States)

Schuster, M.; Pech, T.; Reuter, J.; Wanielik, G.

2014-11-01

Für modernste Fahrerassistenzsysteme ist zunehmend eine vollständige Rundumüberwachung des fließenden Verkehrs erforderlich. In diesem Artikel wird ein Ansatz zur Überwachung des gesamten umliegenden Verkehrs mittels Radarsystemen präsentiert. Hierfür wurde ein Versuchsfahrzeug mit insgesamt sechs Radarsensoren ausgerüstet, um eine möglichst hohe Umfeld-Überwachung zu ermöglichen. Für diese Konfiguration wird ein auf GPDA basierendes Trackingsystem vorgestellt. Es wird auf das Problem ausgedehnter Ziele eingegangen, welches auftritt wenn sich ein Fremdfahrzeug neben dem Versuchsfahrzeug befindet, da hier Reflektionen von verschiedenen Reflektionszentren des Ziels aufgefangen werden. Dieser Effekt wird ausgenutzt, um mittels einer Track-zu-Track Fusion eine Längenschätzung des vorbeifahrenden Fahrzeugs zu ermöglichen.

Alignment and position visualization methods for the biomedical imaging and therapy (BMIT) MRT lift

International Nuclear Information System (INIS)

Bree, Michael; Miller, Denise; Kerr, Graham; Belev, George; Wysokinski, Tomasz W.; Dolton, Wade

2016-01-01

The Microbeam Radiation Therapy (MRT) Lift is an eight stage positioning and scanning system at the Canadian Light Source’s BMIT Facility. Alignment of the sample with the beam using the MRT Lift is a time consuming and challenging task. The BMIT Group has developed a Python-based MRT Lift positioning and control program that uses a combination of computational and iterative methods to independently adjust the sample’s X, Y, Z, pitch and roll positions. The program offers “1-Click” alignment of the sample to the beam. Use of a wireframe visualization technique enables even minute movements to be illustrated. Proposed movements and the resulting MRT Lift position can be manually verified before being applied. Optional integration with the SolidWorks modelling platform allows high quality renderings of the MRT Lift in its current or proposed position to be displayed in real time. Human factors principles are incorporated into the program with the objective of delivering easy to use controls for this complex device.

Alignment and position visualization methods for the biomedical imaging and therapy (BMIT) MRT lift

Energy Technology Data Exchange (ETDEWEB)

Bree, Michael, E-mail: michael.bree@lightsource.ca; Miller, Denise; Kerr, Graham; Belev, George; Wysokinski, Tomasz W.; Dolton, Wade [Canadian Light Source Inc., 44 Innovation Blvd, Saskatoon, SK S7N 2V3 Canada (Canada)

2016-07-27

The Microbeam Radiation Therapy (MRT) Lift is an eight stage positioning and scanning system at the Canadian Light Source’s BMIT Facility. Alignment of the sample with the beam using the MRT Lift is a time consuming and challenging task. The BMIT Group has developed a Python-based MRT Lift positioning and control program that uses a combination of computational and iterative methods to independently adjust the sample’s X, Y, Z, pitch and roll positions. The program offers “1-Click” alignment of the sample to the beam. Use of a wireframe visualization technique enables even minute movements to be illustrated. Proposed movements and the resulting MRT Lift position can be manually verified before being applied. Optional integration with the SolidWorks modelling platform allows high quality renderings of the MRT Lift in its current or proposed position to be displayed in real time. Human factors principles are incorporated into the program with the objective of delivering easy to use controls for this complex device.

MRT of the central nervous system. 2. rev. and enl. ed.; MRT des Zentralnervensystems

Energy Technology Data Exchange (ETDEWEB)

Forsting, Michael [Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie; Jansen, Olav (ed.) [Universitaetsklinikum Schleswig-Holstein, Kiel (Germany). Klinik fuer Radiologie und Neuroradiologie

2014-11-01

The book on MRT of the central nervous system includes the following chapters: anatomy, vascular diseases, brain tumors, craniocerebral injuries, infectious diseases, multiple sclerosis and related diseases, metabolic diseases, degenerative diseases, malformations and developmental disorders, hydrocephalus and intracranial hypertension, spinal marrow, degenerative caused spinal and foraminal stenosis, traumata, tumors and tumor-like neoplasm, vascular diseases, inflammations, infections and related diseases, diseases of the peripheral nervous system.

The diagnosis of inflammatory muscular and vascular conditions using MRT with STIR sequences. Diagnostik entzuendlicher Muskel- und Gefaesserkrankungen in der MRT mit STIR-Sequenzen

Energy Technology Data Exchange (ETDEWEB)

Beese, M.S. (Radiologische Klinik, Universitaetskrankenhaus Eppendorf, Hamburg (Germany)); Winkler, G. (Radiologische Klinik, Universitaetskrankenhaus Eppendorf, Hamburg (Germany) Neurologische Klinik, Universitaetskrankenhaus Eppendorf, Hamburg (Germany)); Nicolas, V. (Radiologische Klinik, Universitaetskrankenhaus Eppendorf, Hamburg (Germany)); Maas, R. (Radiologische Klinik, Universitaetskrankenhaus Eppendorf, Hamburg (Germany)); Kress, D. (Radiologische Klinik, Universitaetskrankenhaus Eppendorf, Hamburg (Germany)); Kunze, K. (Radiologische Klinik, Universitaetskrankenhaus Eppendorf, Hamburg (Germany) Neurologische Klinik, Universitaetskrankenhaus Eppendorf, Hamburg (Germany)); Buecheler, E. (Radiologische Klinik, Universitaetskrankenhaus Eppendorf, Hamburg (Germany))

1993-06-01

The role of MRT in the prebiopsy diagnosis of muscular and vascular inflammatory conditions was evaluated prospectively and an optimal method of examination was investigated. 92 patients with a suspected diagnosis of myositis (60 cases) or vasculitis (32 cases) were examined, in each case two extremities were studied using transverse T[sub 1] and T[sub 2] weighted SE sequences and double echo STIR sequences on a 0.5 Tesla (56 patients) or 1.5 Tesla magnet (36 patients; T5/S15 Gyroscan, Philips). The site of the biopsy depended on the MRT findings. In 41 patients the suspected diagnosis was confirmed histologically, in two patients an infective myositis was diagnosed on clinical grounds despite negative histology. MRT demonstrated muscle oedema in 86% of patients. There were negative findings after immuno-suppressive therapy (two patients), in focal myositis (3 out of 4 patients) and in one of 7 patients with untreated vasculitis. Amongst 49 patients in whom the suspected diagnosis could not be confirmed there was muscle oedema in 11 cases (9 neuropathies out of 22, two myopathies out of 10). Oedema indicated inflammatory muscular or vascular disease with a sensitivity of 97% (except in treated patients and for focal myositis). The number of false negative biopsies can be greatly reduced by the use of MRT. (orig.)

MRI of the fetal abdomen; MRT des fetalen Abdomens

Energy Technology Data Exchange (ETDEWEB)

Hoermann, M.; Brugger, P.C.; Witzani, L.; Prayer, D. [Medizinische Universitaet Wien (Austria). Universitaetsklinik fuer Radiodiagnostik

2006-02-15

Magnetic resonance imaging (MRI) is an important diagnostic component for central nervous system and thoracic diseases during fetal development. Although ultrasound remains the method of choice for observing the fetus during pregnancy, fetal MRI is being increasingly used as an additional technique for the accurate diagnosis of abdominal diseases. Recent publications confirm the value of MRI in the diagnosis of fetal gastrointestinal tract and urogenital system diseases. The following report provides an overview of MRI-examination techniques for the most frequent diseases of the abdomen. (orig.) [German] Die MRT ist ein wichtiger Bestandteil zur Diagnostik des zentralen Nervensystems und thorakaler Erkrankungen in der fetalen Entwicklung. Wenngleich der Ultraschall die Methode der Wahl zur Ueberwachung des Feten in der Schwangerschaft bleibt, bekommt die fetale MRT als zusaetzliche Untersuchungstechnik zur akkuraten Diagnostik abdomineller Erkrankungen immer groessere Bedeutung. Die neueren Publikationen bestaetigen v. a. den Stellenwert der MRT in der Diagnose von Erkrankungen des fetalen Gastrointestinaltrakts und des Urogenitalsystems. Im Folgenden soll ein Ueberblick ueber die MR-Untersuchungstechnik der haeufigsten Erkrankungen des Abdomens gegeben werden. (orig.)

MRI for myocarditis; MRT bei Myokarditis

Energy Technology Data Exchange (ETDEWEB)

Gutberlet, M.; Luecke, C.; Krieghoff, C.; Hildebrand, L.; Steiner, J.; Adam, J.; Grotthoff, M.; Lehmkuhl, L. [Herzzentrum, Universitaet Leipzig, Abteilung fuer Diagnostische und Interventionelle Radiologie, Leipzig (Germany); Lurz, P.; Eitel, I.; Thiele, H. [Herzzentrum, Universitaet Leipzig, Abteilung Kardiologie, Leipzig (Germany)

2013-01-15

Cardiovascular magnetic resonance imaging (CMRI) has become the primary tool for the non-invasive assessment in patients with suspected myocarditis, especially after exclusion of acute coronary syndrome (ACS) for the differential diagnosis. Various MRI parameters are available which have different accuracies. Volumetric and functional ventricular assessment and the occurrence of pericardial effusion alone demonstrate only a poor sensitivity and specificity. The calculation of the T2-ratio (edema assessment), the early or global relative myocardial enhancement (gRE) and the late gadolinium enhancement (LGE), which represents irreversibly injured myocardium, are more specific parameters. All MRI parameters demonstrate the best accuracy in infarct-like acute myocarditis, whereas in chronic myocarditis sensitivity and specificity are less accurate. Therefore, a multisequential (at least two out of three parameters are positive) approach is recommended. The assessment of the value of newer, more quantitative MRI sequences, such as T1 and T2-mapping is still under investigation. (orig.) [German] Die kardiale MRT stellt die primaere nichtinvasive bildgebende Modalitaet bei Verdacht auf Myokarditis dar, insbesondere auch nach Ausschluss eines akuten Koronarsyndroms (ACS) zur Differenzialdiagnose. Verschiedene MR-Parameter mit unterschiedlicher Wertigkeit stehen zur Verfuegung. Die Beurteilung der Volumetrie und Ventrikelfunktion weisen ebenso wie der Nachweis eines Perikardergusses alleine nur eine geringe Sensitivitaet und Spezifitaet auf. Die spezifischeren MRT-Inflammationsparameter stellen die T2-Ratio (Oedemnachweis), die fruehe Kontrastmittelanreicherung bzw. das globale relative Enhancement (gRE) und die spaete Kontrastmittelanreicherung, das so genannte Late-Gadolinium-Enhancement (LGE) als Zeichen eines irreversiblen Myokardschadens dar. Alle MR-Parameter zeigen die beste diagnostische Genauigkeit bei einer ''infarktaehnlichen'' akuten

Die Radiofrequenz-Kyphoplastie - Fallstudie zu multiplen osteoporotischen Sinterungen der Lendenwirbelsäule

Directory of Open Access Journals (Sweden)

Schekelmann R

2010-01-01

Full Text Available Im St. Marien-Krankenhaus wurden von Januar 2007 bis September 2009 insgesamt 176 Patienten mit osteoporotischen Wirbelkörperfrakturen mittels Ballonkyphoplastie (BKP behandelt. Die funktionellen Ergebnisse waren gut; es traten keine interventionspflichtigen Komplikationen auf. Seit September 2009 wurden weitere 41 Patienten bei gleicher Indikation mit dem neuen Verfahren der Radiofrequenz- Kyphoplastie (DFine behandelt. Die OPZeiten waren erheblich verkürzt und die Austrittsrate des Zements konnte um 2/3 verringert werden. Wir sahen weder Komplikationen, noch Kreislauf-Beeinträchtigungen. Das neue Verfahren (RF-Kyphoplastie ergab funktionell gleich gute Ergebnisse wie die BKP, benötigte kürzere OP-Zeiten und reduzierte die Anzahl unerwünschter Nebeneffekte.

Muscle lesion comparing of imaging procedures (sonography and MRT) -experimental and clinical study

International Nuclear Information System (INIS)

Mellerowicz, H.; Lubasch, A.; Dulce, M.; Wagner, S.; Paul, B.

1993-01-01

Muscle injuries in sports are more common now. Diagnosis and follow up of muscle injuries is nowadays achieved by sonography and MRT. In order to assess the two imagine procedures, a direct test for comparison of sonography and MRT was performed in an experimental study: A standardised disconnection of m. triceps surae in rats was either sutured and glued or not treated. Clinical studies were performed in 26 patients suffering from muscle trauma. Sonography was proved to be a reliable procedure especially in follow up control until full weight bearing and should be used first. Negative or doubtfull findings require further investigation by MRT. Especially contrast medium (Gd-DTPA) assisted examinations enables a long term follow up and may even show small (muscle strain) and deep lying injuries. (orig.) [de

Untersuchungen zur Rauchgasentstickung mittels Schwefelwasserstoff in Tri-n-butylphosphat

OpenAIRE

Homann, Jörg

2000-01-01

In der vorliegenden Arbeit wurde die Reaktion von Stickstoffmonoxid (NO) mit Schwefelwassersoff (H2S) in Tri-n-butylphosphat (TBP) im Hinblick auf ein alternatives Verfahren zur Entstickung von Rauchgasen untersucht. Mittels einer gasvolumetrischen Absorptionsapparatur wurden zuerst Daten zur physikalischen Löslichkeit in TBP ermittelt, die für den Erhalt kinetischer Daten der stofftransportüberlagerten Reaktionen in TBP relevant sind. Es sind dies die Henrykoeffizienten von NO, H2S und die d...

MRT Lattice Boltzmann schemes for confined suspension flows

NARCIS (Netherlands)

Sman, van der R.G.M.

2010-01-01

We introduce a novel multiple-relaxation time (modified MRT) Lattice Boltzmann scheme for simulation of confined suspension flow. Via careful tuning of the free eigenvalues of the collision operator we can substantially reduce the error in the so-called hydrodynamic radius. Its performance has been

MRT in differentiation between tumour and implant material in the postoperative sella

International Nuclear Information System (INIS)

Kaiser, W.A.; Steckelbroeck, V.; Siewert, B.; Layer, G.; Hochstetter, A.; Reiser, M.

1993-01-01

MRT criteria have been developed to distinguish between tumour and implant material following examination of 50 patients who had transsphenoidal hypophysectomies for tumours. Judgements were based on the postoperative hormonal status and the operation notes. Following contrast injection of Gd-DTPA and using T 1 weighted spin-echo sequences, implant material appeared as sandwich-like, linear or circular structures. Residual recurrent tumour produced homogenous or non-homogenous aspects without marginal enhancement in 84% of cases. Postoperative displacement of the infundibulum to the opposite side was observed in 73% of patients with tumour remnants. Sensitivity of MRT was 70%, specificity 95%. There was a positive predictive value of 94% and a negative predictive value of 72% with an accuracy of 81%. This provides assistance in differentiating between tumour remnants and implant material. MRT is recommended as a method of examination for hypophyseal tumours to evaluate the success of surgery and where there is clinical doubt concerning residual or recurrent tumour. (orig.) [de

MRI methods for pulmonary ventilation and perfusion imaging; Methoden der MRT zur Ventilations- und Perfusionsbildgebung der Lunge

Energy Technology Data Exchange (ETDEWEB)

Sommer, G. [Universitaetsspital Basel, Klinik fuer Radiologie und Nuklearmedizin, Basel (Switzerland); Bauman, G. [Universitaetsspital Basel, Klinik fuer Radiologie und Nuklearmedizin - Radiologische Physik, Basel (Switzerland)

2016-02-15

Detektion frueher pathologischer Veraenderungen. Standardverfahren der bildgebenden Lungendiagnostik sind die Computertomographie (CT) zur morphologischen Darstellung und die Perfusions-/Ventilationsszintigraphie bzw. ''single photon emission computed tomography'' (SPECT) zur funktionellen Diagnostik. Zur Darstellung der Lungenventilation stehen die MRT mit hyperpolarisierten Gasen, die O{sub 2}-verstaerkte MRT, die MRT mit fluorierten Gasen und die Fourier-Dekompositions-MRT (FD-MRT) zur Verfuegung. Zur Perfusionsbestimmung koennen die dynamische kontrastmittelverstaerkte MRT (DCE-MRT), das ''arterial spin labeling'' (ASL) und die FD-MRT verwendet werden. Bildgebende Verfahren erlauben einen genaueren Einblick in die Pathophysiologie der Lungenfunktion auf regionaler Ebene. Vorteile der MRT sind die fehlende Strahlenbelastung, welche die schonende Akquisition dynamischer Daten ermoeglicht sowie die Vielfalt der verfuegbaren Kontraste und damit zugaenglichen Parameter der Lungenfunktion. Ausreichende klinische Daten existieren nur fuer bestimmte Anwendungen der DCE-MRT. Fuer die uebrigen Verfahren gibt es lediglich Machbarkeitsstudien und Fallserien mit unterschiedlichem Umfang. Hyperpolarisierte Gase sind technisch bedingt nur eingeschraenkt in der Klinik anwendbar. Ein klinischer Einsatz der genannten Verfahren sollte mit Ausnahme der DCE-MRT nur innerhalb von Studien erfolgen. (orig.)

Health co-benefits in mortality avoidance from implementation of the mass rapid transit (MRT) system in Kuala Lumpur, Malaysia.

Science.gov (United States)

Kwan, Soo Chen; Tainio, Marko; Woodcock, James; Hashim, Jamal Hisham

2016-03-01

The mass rapid transit (MRT) is the largest transport infrastructure project under the national key economic area (NKEA) in Malaysia. As urban rail is anticipated to be the future spine of public transport network in the Greater Kuala Lumpur city, it is important to mainstream climate change mitigation and public health benefits in the local transport development. This study quantifies the health co-benefits in terms of mortality among the urbanites when the first line of the 150 km MRT system in Kuala Lumpur commences by 2017. Using comparative health risk assessment, we estimated the potential health co-benefits from the establishment of the MRT system. We estimated the reduced CO2 emissions and air pollution (PM2.5) exposure reduction among the general population from the reduced use of motorized vehicles. Mortality avoided from traffic incidents involving motorcycles and passenger cars, and from increased physical activity from walking while using the MRT system was also estimated. A total of 363,130 tonnes of CO2 emissions could be reduced annually from the modal shift from cars and motorcycles to the MRT system. Atmospheric PM2.5 concentration could be reduced 0.61 μg/m3 annually (2%). This could avoid a total of 12 deaths, mostly from cardio-respiratory diseases among the city residents. For traffic injuries, 37 deaths could be avoided annually from motorcycle and passenger cars accidents especially among the younger age categories (aged 15-30). One additional death was attributed to pedestrian walking. The additional daily physical activity to access the MRT system could avoid 21 deaths among its riders. Most of the mortality avoided comes from cardiovascular diseases. Overall, a total of 70 deaths could be avoided annually among both the general population and the MRT users in the city. The implementation of the MRT system in Greater Kuala Lumpur could bring substantial health co-benefits to both the general population and the MRT users mainly from the

Anatomy of the fingers in MR imaging using a high resolution surface coil; Die Anatomie der Finger in der MRT unter Anwendung einer Hochaufloesungsspule

Energy Technology Data Exchange (ETDEWEB)

Maeurer, J. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany); Mueller, H.F. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany); Lemke, A.J. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany); Requardt, R. [Siemens AG, Erlangen (Germany); Stein, I. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany); Schedel, H. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany); Langer, R. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany); Felix, R. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany)

1994-12-31

MR-images of the fingers of twenty healthy volunteers were obtained at a 1,5-T whole-body system with a high resolution coil. Additionally, the fingers of two formalin-fixed anatomical specismen were imaged, fronzen and then subsequently sectioned for anatomic correlation. Measurements were recorded with a slice thickness of 2 mm. A 256x256 matrix and a 2,5 cam fiel of view (FOV) were used resulting in a pixel size of 0,01 mm{sup 2}. Based on the excellent depiction of anatomic detail and contrast resolution high resolution MRI of the fingers enabled identification of osseous and cartilaginous structures, as well as delineation of tendons, ligaments blood-vessels and dermal layers. (orig.) [Deutsch] An einem 1,5-T-Ganzkoerpertomographen wurden die Finger von 20 gesunden Probanden mit einer Hochaufloesungsspule zur Darstellung der Anatomie untersucht. Zum Vergleich erfolgte die Abbildung der anatomischen Strukturen an zwei formol- und alkoholfixierten Leichepraeparaten der Hand mittels MRT. Im Anschluss wurden die untersuchten Regionen am tiefgefrorenen Praeparat mit einer Bandsaege nachgeschnitten. Die MR-Messungen wurden mit einer Schichtdicke von 3 mm, einem Field of View (FOV) von 25 mm und einer Matrix von 256x256 Pixel durchgefuehrt. Die daraus resultierende Pixelgroesse betrug 0,01 mm{sup 2}. Der Weichteilkontrast und die hohe Ortsaufloesung ermoeglichten die Identifikation von Knochen- und Knorpelstrukturen sowie die Abgrenzung von Sehnen, Baendern, Blutgefaessen und Hautschichten. (orig.)

MRI of pulmonary embolism; MRT der akuten Lungenembolie

Energy Technology Data Exchange (ETDEWEB)

Fink, C.; Schoenberg, S.O. [Universitaetsklinikum Mannheim, Medizinische Fakultaet Mannheim der Universitaet Heidelberg, Institut fuer Klinische Radiologie, Mannheim (Germany); Thieme, S.; Clevert, D.; Reiser, M.F. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Klinische Radiologie, Muenchen (Germany); Ley, S. [Deutsches Krebsforschungszentrum Heidelberg, Abteilung Radiologie, Heidelberg (Germany); Universitaetsklinikum Heidelberg, Abteilung Paediatrische Radiologie, Heidelberg (Germany); Kauczor, H.U. [Deutsches Krebsforschungszentrum Heidelberg, Abteilung Radiologie, Heidelberg (Germany)

2007-08-15

Recent technical developments have substantially improved the potential of MRI for the diagnosis of pulmonary embolism. On the MR scanner side this includes the development of short magnets and dedicated whole-body MRI systems, which allow a comprehensive evaluation of pulmonary embolism and deep venous thrombosis in a single exam. The introduction of parallel imaging has substantially improved the spatial and temporal resolution of pulmonary MR angiography. By combining time-resolved pulmonary perfusion MRI with high-resolution pulmonary MRA a sensitivity and specificity of over 90% is achievable, which is comparable to the accuracy of CTA. Thus, for certain patient groups, such as patients with contraindications to iodinated contrast media and young women with a low clinical probability for pulmonary embolism, MRI can be considered as a first-line imaging tool for the assessment of pulmonary embolism. (orig.) [German] Technische Weiterentwicklungen der MRT haben deren Moeglichkeiten fuer die Diagnostik der Lungenembolie erheblich verbessert. Hierzu zaehlen auf Geraeteseite kuerzere Magneten sowie dedizierte Ganzkoerper-MRT-Systeme, die einerseits den Patientenzugang beguenstigen und andererseits eine Abklaerung einer potenziell zugrunde liegenden Venenthrombose in einer Untersuchung ermoeglichen. Auf Seite der Sequenztechnik hat die Einfuehrung der parallelen Bildgebung die raeumliche und zeitliche Aufloesung der MR-Angiographie (MRA) der Lunge deutlich verbessert. Durch eine Kombination zeitaufgeloester Messungen der Lungenperfusion und einer raeumlich hochaufgeloesten MRA kann fuer die Diagnostik der Lungenembolie eine Sensitivitaet und Spezifitaet von ueber 90% erzielt werden, was vergleichbar der Genauigkeit der CT-Angiographie (CTA) ist. Daher kann die MRT fuer bestimmte Personen, wie z. B. Patienten mit Kontraindikationen gegen jodhaltige Roentgenkontrastmittel (z. B. Hyperthyreose) oder juengere Frauen mit einer geringen klinischen Wahrscheinlichkeit fuer

Magnetic resonance tomography and dental radiology (Dental-MRT)

International Nuclear Information System (INIS)

Gahleitner, A.; Wien Univ.; Solar, P.; Ertl, L.; Nasel, C.; Homolka, P.; Youssefzadeh, S.; Schick, S.

1999-01-01

Purpose: To demonstrate the usefulness of Dental-MRT for imaging of anatomic and pathologic conditions of the mandible and maxilla. Methods: Seven healthy volunteers, 5 patients with pulpitis, 9 patients with dentigerous cysts, 5 patients after tooth transplantation and 12 patients with atrophic mandibles were evaluated. Studies of the jaws using axial T1- and T2-weighted gradient echo and spin echo sequences in 2D and 3D technique have been to performed. The acquired images were reconstructed with a standard dental software package on a workstation as panoramic and cross sectional views of the mandible or maxilla. Results: The entire maxilla and mandibula, teeth, dental pulp and the content of the mandibular canal were well depicted. Patients with inflammatory disease of the pulp chamber demonstrate bone marrow edema in the periapical region. Dentigerous cysts and their relation to the surrounding structures are clearly shown. After contrast media application marked enhancement of the dental pulp can be found. Conclusion: Dental-MRT provides a valuable tool for visualization and detection of dental diseases. (orig.) [de

Radiologic diagnostics of dementia; Radiologische Demenzdiagnostik

Energy Technology Data Exchange (ETDEWEB)

Essig, M. [Radiologie, Deutsches Krebsforschungszentrum Heidelberg (Germany); Radiologie, Deutsches Krebsforschungszentrum Heidelberg, Im Neuenheimer Feld 280, 69120, Heidelberg (Germany); Schoenberg, S.O. [Institut fuer klinische Radiologie, Ludwig-Maximilians-Universitaet Muenchen (Germany)

2003-07-01

Dementia is one of the most common diseases in the elderly population and is getting more and more important with the ageing of the population. A radiologic structural examination with CT or MRI is meanwhile a standard procedure in the diagnostic work up of patients with dementia syndrome. Radiology enables an early diagnosis and a differential diagnosis between different causes of dementia. Because structural changes occur only late in the disease process, a more detailed structural analysis using volumetric techniques or the use of functional imaging techniques is mandatory. These days, structural imaging uses MRI which enables to detect early atrophic changes at the medial temporal lobe with focus on the amygdala hippocampal complex. These changes are also present in the normal ageing process. In patients with Alzheimer's disease, however, they are more rapid and more pronounced. The use of functional imaging methods such as perfusion MRI, diffusion MRI or fMRI allow new insights into the pathophysiologic changes of dementia. The article gives an overview of the current status of structural imaging and an outlook into the potential of functional imaging methods. Detailed results of structural and functional imaging are presented in other articles of this issue. (orig.) [German] Demenzielle Syndrome gehoeren zu den haeufigsten Erkrankungen im hoeheren Lebensalter und werden mit einer Zunahme der Ueberalterung in der Bevoelkerung volkswirtschaftlich immer bedeutender. Die radiologische Untersuchung mittels struktureller CT oder MRT gehoert mittlerweile zur Standardabklaerung jeder demenziellen Symptomatik. Sie dient der Frueherkennung und der Differenzialdiagnostik der verschiedenen Ursachen einer Demenz. Dies gilt insbesondere in Hinblick auf zu erwartende und bereits vorhandene Therapiemoeglichkeiten. Da jedoch strukturelle Veraenderungen erst relativ spaet im Fortschreiten der Erkrankung visualisiert werden koennen, sind detaillierte strukturelle

MUNICIPAL BONDS AS THE FINANCING STRATEGY FOR URBAN INFRASTRUCTURE : CASE STUDY OF JAKARTA MRT

Directory of Open Access Journals (Sweden)

Eko Nur Surachman

2016-10-01

Full Text Available The construction of Jakarta MRT Phase I has been carried out by using funds from foreign debt. Meanwhile, Jakarta MRT Phase II or other local infrastructure projects are still waiting for new funding scheme. One alternative is municipal bonds. This study investigate the possibilities of using municipal bonds to finance urban infrastructure project with the case study of Jakarta MRTPhase I. The analyzed use three perspectives including financial aspect, legal aspect, and Jakarta financial capacity aspect. financial analysis using discounted cash flow (DCF, net present value (NPV and internal rate of return (IRR.Secondly, study literature is used in the legal analysis by exploring specific regulations regarding the municipal bonds. Finally, the Jakarta Regional Budget and Jakarta Budget Audit Report is examined to get insight and depth information regarding its financial capacity. The result is municipal bonds are feasible as the source of financing Jakarta MRT Project.

Functional magnetic resonance imaging with ultra-high fields; Funktionelle Magnetresonanztomographie bei ultrahohen Feldern

Energy Technology Data Exchange (ETDEWEB)

Windischberger, C.; Schoepf, V.; Sladky, R.; Moser, E. [Medizinische Universitaet Wien, Exzellenzzentrum Hochfeld-MR, Wien (Austria); Medizinische Universitaet Wien, Zentrum fuer Medizinische Physik und Biomedizinische Technik, Wien (Austria); Fischmeister, F.P.S. [Medizinische Universitaet Wien, Exzellenzzentrum Hochfeld-MR, Wien (Austria); Universitaet Wien, Fakultaet fuer Psychologie, Wien (Austria)

2010-02-15

Functional magnetic resonance imaging (fMRI) is currently the primary method for non-invasive functional localization in the brain. With the emergence of MR systems with field strengths of 4 Tesla and above, neuronal activation may be studied with unprecedented accuracy. In this article we present different approaches to use the improved sensitivity and specificity for expanding current fMRT resolution limits in space and time based on several 7 Tesla studies. In addition to the challenges that arise with ultra-high magnetic fields possible solutions will be discussed. (orig.) [German] Die funktionelle Magnetresonanztomographie (fMRT) stellt zurzeit die wichtigste Methode zur nichtinvasiven Funktionslokalisation im Gehirn dar. Mit der Verfuegbarkeit von MRT-Geraeten mit Magnetfeldstaerken von 4 Tesla (T) und darueber ergeben sich neue Moeglichkeiten, mittels fMRT die neuronale Aktivitaet in bislang unerreichter Genauigkeit zu untersuchen. In diesem Artikel zeigen wir anhand mehrerer Studien bei 7 T, in wieweit die Zugewinne an Sensitivitaet und Spezifitaet verwendet werden koennen, um die bisherigen Grenzen der fMRT-Aufloesung in raeumlicher und zeitlicher Hinsicht auszuweiten. Die neuen Herausforderungen, die mit dem Schritt zu ultrahohen Magnetfeldern einhergehen, werden dabei ebenso diskutiert wie moegliche Ansaetze zu deren Loesung. (orig.)

Urämische Kardiomyopathie und der Einfluss der Hämodialyse

OpenAIRE

Valina, Ulrike Katrin

2011-01-01

ZIEL: Analyse von Risikofaktoren und Entstehungsmechanismen der urämischen Kardiomyopathie bei Hämodialysepatienten und Vergleich von Diagnostiken zur frühen Detektion kardialer Funktionstörungen zur Optimierung der Therapie bei terminaler Niereninsuffizienz und Senkung der hohen Mortalitätsrate. METHODEN: Einschluss von 32 Hämodialysepatienten. Messungen mittels Blutentnahme (Entzündungs-, Atherosklerose-, Anämieparameter, EPO, PTH und RAAS) und MRT (Herzfunktion, Herzmorphologie und Her...

MRT versus CT in the diagnosis of pneumonia. Evaluation of a T2-weighted utrafast turbo-spin-echo sequence (UTSE)

International Nuclear Information System (INIS)

Leutner, C.; Lutterbey, G.; Kuhl, C.K.; Flacke, S.; Schild, H.H.; Glasmacher, A.; Theisen, A.; Wardelmann, E.; Grohe, C.

1999-01-01

Purpose: To evaluate a T 2 -weighted URSE sequence for the assessment of pulmonary infiltrations in comparison to CT. Methods: 28 MRT scans of 22 patients with confirmed pneumonia were recorded on a 1.5 Tesla apparatus with an expiratory and diastolic triggered, T 2 -weighted ultrafast-spin-echo sequence in axial slice mode with the following parameters: TR eff /T E /Turbofactor 2000-4000/90 ms/21-23; slice thickness/separation 6/0.6 mm; FOV 360 mm; 24 slices. 24 spiral CTs (sice thickness/table advance: 1-2 mm/10 mm) were available for comparison. The separate evaluation of MRTs and CTs was performed by three radiologists in a consensus procedure with regard to pulmonary lesions (e.g., infiltration, round foci, net patterns) and image quality of the MRTs (4-step scale). Results: In 71% of the cases the CTs and MRTs agreed with the diagnosis and representation of the lesions, in 25% MRT was superior. MRT was better for the detection of pulmonary abscesses. In 93% the image quality of the MRT was very good to good. Conclusions: MRT in the technique presented here is in most cases equal to CT for the detection of pneumonia. Diagnosis of pulmonary abscesses seems to be better with MRT. (orig.) [de

Analyses of functional brain connectivity; Untersuchungen zur funktionellen Konnektivitaet des Gehirns

Energy Technology Data Exchange (ETDEWEB)

Stephan, K.E.

2003-03-01

This dissertation includes two independent studies that investigate two complementary aspects of functional connectivity in the Macaque and the human brain. In the first study, a computational meta-analysis of published electrophysiological data on context-independent functional brain connectivity was conducted by means of three independent methods. The second study investigated the effects of the atypical antipsychotic substance olanzapine on the functional connectivity of the cerebellum during a simple motor task (self-paced finger tapping). Six schizophrenic patients and six control subjects matched for age and sex were investigated by functional magnetic resonance imaging (fMRI) twice. This study provided the first experimental data on the effects of atypical antipsychotic agents on functional brain connectivity and demonstrated pronounced olanzapine-dependent changes of functional couplings between cerebellum, thalamus, and prefrontal cortex. (orig.) [German] In der hier vorgelegten Arbeit werden zwei komplementaere Aspekte der funktionellen Konnektivitaet - im Gehirn des Makaken und Menschen anhand zweier separater Studien untersucht. In der ersten Studie wurde mittels dreier unabhaengiger Methoden eine Metaanalyse publizierter elektrophysiologischer Daten zur kontextunabhaengigen funktionellen Konnektivitaet des Makakenkortex durchgefuehrt. Diese Studie erbrachte damit zum ersten Mal den Nachweis einer funktionellen Small World-Netzwerkstruktur des Primatenkortex. In der zweiten Studie wurde der Effekt des atypischen Neuroleptikums Olanzapin auf die funktionelle Konnektivitaet des Zerebellums im Kontext einer einfachen motorischen Aufgabe (selbstgesteuertes Fingertrapping) untersucht. Sechs schizophrene Patienten, die Neuroleptika-naiv bzw. -entwoehnt waren, sowie sechs alters- und geschlechtsentprechende Kontrollprobanden wurden im Abstand von jeweils drei Wochen mit funktioneller Magnetresonanztomografie (fMRT) untersucht. Diese Studie lieferte die ersten

Prognostic value of cardiovascular MRI in diabetics; Prognostischer Wert der kardiovaskulaeren MRT bei Diabetikern

Energy Technology Data Exchange (ETDEWEB)

Schlett, C.L.; Bertheau, R.C.; Kauczor, H.U.; Weckbach, S. [Universitaetsklinikum Heidelberg, Klinik fuer Diagnostische und Interventionelle Radiologie, Heidelberg (Germany)

2015-04-01

Risikostratifizierung von Noeten ist. Die klinische Untersuchung und die Bestimmung von Blutwerten dienen bei Diabetikern typischerweise zur Risikostratifizierung bzgl. kardio(zerebro)vaskulaerer Ereignisse in der Zukunft. Sowohl die Kardio- als auch die Ganzkoerper-MRT stellen standardisierte Verfahren in der klinischen Diagnostik dar. Deren Stellenwert bei der Vorhersage von Ereignissen mit entsprechender Risikostratifizierung bei Diabetikern gewinnt basierend auf aktuellen Studienergebnissen zunehmend an Bedeutung. Late Gadolinium Enhancement (LGE) im Kardio-MRT detektiert bei bis zu 30 % der Diabetiker stumme Myokardischaemien, die mit einer Hazard Ratio von 3-6 mit kardiovaskulaeren Ereignissen assoziiert sind. Ebenfalls zeigen linksventrikulaere Wandbewegungsstoerungen sowie eine erniedrigte Ejektionsfraktion einen prognostischen Wert. Im Ganzkoerper-MRT sind der Vessel-Score und Karotisstenosen zusaetzliche Praediktoren fuer kardio(zerebro)vaskulaere Ereignisse. Die MRT-basierte Vorhersage kardio(zerebro)vaskulaerer Ereignisse bietet einen signifikanten Mehrwert zur klassischen Risikostratifizierung bei Diabetikern. Jedoch erlaubt nur die umfassende Ganzkoerper-MRT-Untersuchung Patienten zu identifizieren, die ueber einen Zeitraum von 6 Jahren komplett frei von kardio(zerebro)vaskulaeren Ereignissen bleiben. Die Kardio-MRT, insbesondere die Erfassung von LGE, empfiehlt sich fuer die Vorhersage von Ereignissen. Die Ganzkoerper-MRT stellt einen prognostischen Mehrwert dar, deren klinische Relevanz in weiteren Studien geklaert werden muss. (orig.)

The technique of MRT aided abdominal drainage using an open low field magnet. Feasibility and first results

International Nuclear Information System (INIS)

Gehl, H.B.; Frahm, C.; Schimmelpenning, H.; Weiss, H.D.

1996-01-01

To test the practicality of MRT-aided drainage using an open low field magnet and to report on the early clinical results. So far seven patients have been treated (four subphrenic abscesses, two psoas abscesses and one pancreatic pseudocyst). The planning of the approach and catheter insertion were carried out under MRT control (Magnetom Open, 0.2 T). Subsequent treatment was controlled by CT and fluoroscopy. Initial puncture was carried out with a non-magnetic 18 gauge Chiba needle. The drainage catheter was introduced by Seldinger's technique in six cases and with a trocar in one patient. In all seven patients drainage could be started successfully. The design of the magnet and coils permitted adequate accessibility of the patient. There were no problems in visualising the puncture needle. Controlling the position of the catheter by MRT was, however, difficult. The first two steps in abscess drainage (planning the approach and inserting the catheter) can be carried out under MRT control. For further catheter control and observing the course of the disease we presently prefer CT or fluoroscopy. (orig.) [de

3D Simulation of Self-Compacting Concrete Flow Based on MRT-LBM

Directory of Open Access Journals (Sweden)

Liu-Chao Qiu

2018-01-01

Full Text Available A three-dimensional multiple-relaxation-time lattice Boltzmann method (MRT-LBM with a D3Q27 discrete velocity model is applied for simulation of self-compacting concrete (SCC flows. In the present study, the SCC is assumed as a non-Newtonian fluid, and a modified Herschel–Bulkley model is used as constitutive mode. The mass tracking algorithm was used for modeling the liquid-gas interface. Two numerical examples of the slump test and enhanced L-box test were performed, and the calculated results are compared with available experiments in literatures. The numerical results demonstrate the capability of the proposed MRT-LBM in modeling of self-compacting concrete flows.

Imaging in syndrome complex diabetes mellitus. Current standards and future perspectives; Bildgebung im Syndromkomplex Diabetes mellitus. Stellenwert und Chancen

Energy Technology Data Exchange (ETDEWEB)

Hetterich, H.; Schafnitzel, A. [Klinikum der Ludwig-Maximilians-Universitaet, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Bamberg, F. [Eberhard-Karls-Universitaet, Abteilung fuer Diagnostische und Interventionelle Radiologie, Tuebingen (Germany)

2015-04-01

Diabetes mellitus is a highly prevalent multisystemic disorder with numerous potential complications and substantial socioeconomic consequences. In many cases, the patient history, physical examination and laboratory tests are not sufficient for a comprehensive evaluation of complicating disorders. Imaging modalities, such as sonography, computed tomography (CT) and magnetic resonance imaging (MRI) are of major significance in the evaluation of complicating disorders of diabetes according to current guidelines. Examples include assessment of coronary artery disease, peripheral artery disease, stroke and diabetic foot syndrome. Technical developments allow a substantial reduction in radiation dose and scan time in CT and MRI, respectively and could therefore justify a broader application in this patient population. In the future CT and MRI could also be used for the early detection of diabetic complications. Furthermore, they could also be used for risk stratification, e.g. measurement of hepatic fat content and evaluation of atherosclerosis in whole body MRI. Prior to widespread application of advanced imaging techniques in this patient population, improved outcomes with respect to survival, quality of life and cost-effectiveness need to be demonstrated. Diagnostic imaging modalities for the evaluation of the syndrome complex of diabetic disorders should be used according to the current guidelines but the use is predicted to increase given the high potential in this population. (orig.) [German] Diabetes mellitus ist eine hochpraevalente Multisystemerkrankung mit zahlreichen Komplikationen und bedeutenden soziooekonomischen Konsequenzen. Die Folgeerkrankungen koennen oft nicht abschliessend mittels Anamnese, koerperlicher Untersuchung und laborchemischen Verfahren evaluiert werden. Radiologische Verfahren wie die Sonographie, Computertomographie (CT) und Magnetresonanztomographie (MRT) haben gemaess verschiedener Leitlinien einen festen Stellenwert bei der

Hydro-MRI for abdominal diagnostics in children; Hydro-MRT in der Darmdiagnostik bei Kindern

Energy Technology Data Exchange (ETDEWEB)

Kern, A.; Schunk, K.; Oberholzer, K.; Thelen, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Kessler, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Kinderchirurgie

2001-11-01

Darmkontrastierung mit 1 l Mannitolloesung mittels MRT an einem 1,0-T-System untersucht. Es kamen transversale und coronare atemangehaltene Sequenzen (T2-HASTE-Sequenzen ohne und mit Fettsupprimierung) sowie kontrastmittelverstaerkte T1-FLASH-Sequenzen zum Einsatz. Die Untersuchungen wurden hinsichtlich der Beurteilbarkeit der einzelnen Darmabschnitte, des Ausmasses und Schweregrades entzuendlicher Veraenderungen sowie extraintestinaler Befunde ausgewertet. Ergebnisse: In 21/24 Untersuchungen konnten der komplette Duenndarm, in 15/24 Faellen zusaetzlich Anteile des Dickdarms dargestellt werden. In 3/24 Faellen war die Beurteilbarkeit des terminalen ileums eingeschraenkt. In 3/24 Untersuchungen traten geringe Atemartefakte auf. Folgende Befunde wurden erhoben: Veraenderungen bei M. Crohn (n = 4), ileitis terminalis (n = 3), ileitis terminalis mit Lymphadenitis mesenterialis (n = 1), Kolitis (n = 2), massive Koprostase (n = 1). Extraintestinal wurden Ovarialzysten (n = 3) und ein Pleuraerguss (n = 1) nachgewiesen. In 4 Untersuchungen fand sich freie Fluessigkeit ohne zusaetzliche pathologische Befunde. Bei 5 Untersuchungen konnten keine pathologischen Veraenderungen nachgewiesen werden. Die Untersuchung wurde von den Kindern gut toleriert; Nebenwirkungen durch die Darmkontrastierung wurden nicht beobachtet. (orig.)

MRT of the locomotor system. 4. rev. and enl. ed.

International Nuclear Information System (INIS)

Vahlensieck, Martin; Reiser, Maximilian

2015-01-01

The book on MRT of the locomotor system covers the following topics: relevant NMT imaging techniques, spinal cord, shoulder, elbows, wrist and fingers, hip region, knee, lower leg - ankle - foot, temporomandibular joint, skeletal muscles, bone marrow, bone and soft tissue tumors, osteoporosis, sacroiliac joint, jaw and periodontium.

Applications of cerebral MRI in neonatology; MRT bei Neugeborenen mit Verdacht auf zerebrale Stoerung

Energy Technology Data Exchange (ETDEWEB)

Prayer, D. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria). Abt. fuer Neuroradiologie; Kuhle, S. [Universitaetsklinik fuer Kinder- und Jugendheilkunde, Wien (Austria). Abt. fuer Neonatologie, angeborene Stoerungen und Intensivmedizin; Blaicher, W. [Abt. fuer Frauenheilkunde und Praenatale Diagnostik, Wien (Germany)

2000-01-01

Magnetic resonance tomography (MRT) has become the most important method in the workup of infantile cerebral complications after primary sonography. Cerebral MR examination and image interpretation during the infantile period require extensive knowledge of morphological manifestations, their pathophysiological background, and frequency. The choice of imaging parameters and image interpretation is demonstrated in infarctions and hemorrhages of the mature and immature brain. A review of the main differential diagnoses is also given. The relevance of MR spectroscopy and fetal MRI is discussed. (orig.) [German] Zur Abklaerung zerebraler Veraenderungen bei Neugeborenen hat sich die Magnetresonanztomographie (MRT) als wichtigste weiterfuehrende Methode nach der Sonographie entwickelt. Die Durchfuehrung und Auswertung der MR-Untersuchungen erfordern jedoch eine genaue Kenntnis der morphologischen Manifestation, des pathophysiologischen Hintergrunds und der Haeufigkeit bestimmter zerebraler Komplikationen in diesem Lebensalter. Resuemee: Ausgehend von zerebrovaskulaeren Erkrankungen werden diese Fragen behandelt, wobei sowohl auf die Auswahl der adaequaten Untersuchungsparameter als auch auf die Bildinterpretation und die wichtigsten Differentialdiagnosen eingegangen wird. Die Bedeutung von MR-Spektroskopie und fetaler MRT wird diskutiert. (orig.)

Quantitatively evaluated dynamic MRT in rheumatoid arthritis of the knee joint

International Nuclear Information System (INIS)

Koenig, H.; Bolze, X.; Wolf, K.J.; Sieper, J.

1992-01-01

32 patients with chronic polyarthritis were examined by MRT. Following intra-articular application of 25 mg prednisolon, 18 patients were reexamined after two of three weeks and 7 out of 18 patients were re-examined after 8 to 16 weeks, both by MRT and clinically. After an initial double echo sequence, we carried out a dynamic series of FLASH measurements (TR 30, TE 10 ms, 70deg) following an intravenous bolus of 0.1 mmol gadolinium-DTPA. Single intensity-time curves were treated quantitatively in relation to the pannus, muscles and effusions. Two or three weeks after treatment the curve parameters showed a reduction in pannus vascularisation which remained constant for the 8 to 16 weeks of further observation. Contrast diffusion in the pannus is initially reduced but approaches the early measurements at the time of the second examination. (orig.) [de

MRI of interstitial lung diseases. What is possible?; MRT bei interstitiellen Lungenerkrankungen. Was ist moeglich

Energy Technology Data Exchange (ETDEWEB)

Biederer, J. [Kreisklinik Gross-Gerau, Radiologie Darmstadt, Gross-Gerau (Germany); Universitaetsklinikum Heidelberg, Klinik fuer Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Deutsches Zentrum fuer Lungenforschung (DZL), Translational Lung Research Center (TLRC) Heidelberg, Heidelberg (Germany); Thoraxklinik, Universitaetsklinikum Heidelberg, Klinik fuer Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Heidelberg (Germany); Wielpuetz, M.O.; Jobst, B.J.; Dinkel, J. [Universitaetsklinikum Heidelberg, Klinik fuer Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Deutsches Zentrum fuer Lungenforschung (DZL), Translational Lung Research Center (TLRC) Heidelberg, Heidelberg (Germany); Thoraxklinik, Universitaetsklinikum Heidelberg, Klinik fuer Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Heidelberg (Germany)

2014-12-15

Magnetic resonance imaging (MRI) of the lungs is becoming increasingly appreciated as a third diagnostic imaging modality besides chest x-ray and computed tomography (CT). Its value is well acknowledged for pediatric patients or for scientific use particularly when radiation exposure should be strictly avoided. However, the diagnosis of interstitial lung disease is the biggest challenge of all indications. The objective of this article is a summary of the current state of the art for diagnostic MRI of interstitial lung diseases. This article reflects the results of a current search of the literature and discusses them against the background of the authors own experience with lung MRI. Due to its lower spatial resolution and a higher susceptibility to artefacts MRI does not achieve the sensitivity of CT for the detection of small details for pattern recognition (e.g. fine reticulation and micronodules) but larger details (e.g. coarse fibrosis and honeycombing) can be clearly visualized. Moreover, it could be shown that MRI has the capability to add clinically valuable information on regional lung function (e.g. ventilation, perfusion and mechanical properties) and inflammation with native signal and contrast dynamics. In its present state MRI can be used for comprehensive cardiopulmonary imaging in patients with sarcoidosis or for follow-up of lung fibrosis after initial correlation with CT. Far more indications are expected when the capabilities of MRI for the assessment of regional lung function and activity of inflammation can be transferred into robust protocols for clinical use. (orig.) [German] Die MRT der Lunge entwickelt sich zu einer ernstzunehmenden dritten Saeule der Thoraxdiagnostik neben dem Thoraxroentgen und der Computertomographie (CT). Ihr Wert in der paediatrischen Lungendiagnostik oder fuer den wissenschaftlichen Einsatz, insbesondere wenn eine Strahlenexposition vermieden werden soll, ist unbestritten. Von allen Indikationen stellt die Diagnostik

Cerebral activation studies by PET and fMRT, clinical relevance?

International Nuclear Information System (INIS)

Brandt, T.

1997-01-01

Cerebral activation studies by PET and fMRT will gain increasing clinical relevance for functional neuroanatomy (reading, speaking), localisation of largely unknown cortical functions (vestibular cortex), imaging of subjective complaints of functional impairments (pain, smell, memory), and documentation of neurological rehabilitation at neuronal level (regeneration, compensation, substitution, learning). (orig.) [de

Dental magnetic resonance tomography (dental-MRT) as a method for imaging of the maxillo-mandibular bone; Dentale Magnetresonanztomographie (Dental-MRT) als Verfahren zur Darstellung des maxillomandibulaeren Zahnhalteapparates

Energy Technology Data Exchange (ETDEWEB)

Gahleitner, A.; Nasel, C.; Schick, S.; Dorffner, S.; Imhof, H.; Trattnig, S. [Wien Univ. (Austria). Abt. fuer Osteologie; Bernhart, T.; Mailath, G.; Watzek, G. [Wien Univ. (Austria). Abt. fuer Orale Chirurgie

1998-10-01

Purpose: To establish a new method for dental imaging using magnetic resonance tomography named Dental-MRT and to demonstrate its usefulness in diagnosing dentogen pathologies of the mandible and maxilla. Methods: Seven healthy volunteers, three patients with pulpitis, two patients with dentigerous cysts, two patients after tooth transplantation, and three patients with atrophic mandibles have been evaluated. Optimized axial T{sub 1}- and T{sub 2}-weighted gradient echo and spin echo sequences in 2D and 3D technique have been established to perform studies of the jaws. The acquired images were reconstructed with a standard dental software package on a workstation as panorama and cross-sectional views of the mandible or maxilla. Results: The entire maxillo-mandibular bone, teeth, dental pulp, and the content of the mandibular canal were well depicted. Patients with pulpitis demonstrate bone marrow edema in the periapical region. Dentigerous cysts and their relation to the surrounding structures are clearly shown. After contrast media administration marked enhancement of the dental pulp can be demonstrated. Conclusion: Dental-MRT promises to provide a new tool for visualization and detection of dental diseases. (orig.) [Deutsch] Ziel: Das Vorstellen der Dental-MRT als neue Methode zur Darstellung des Ober- und Unterkiefers und ihre Anwendung bei der Diagnose zahnmedizinischer Erkankungen. Methoden: 7 gesunde Probanden, drei Patienten mit Pulpitis, zwei Patienten mit odontogenen Zysten, zwei Patienten nach Zahntransplantationen und drei Patienten mit atrophem Unterkiefer wurden untersucht. Optimierte axiale T{sub 1}- und T{sub 2}-gewichtete Gradienten-Echo- und Spin-Echo-Sequenzen in 2D und 3D-Technik wurden angewandt. Nach der Untersuchung wurden Panoramaschnitte und dentale Rekonstruktionen des Ober- und Unterkiefers, unter Verwendung einer gebraeuchlichen Dental-Software, angefertigt. Ergebnisse: Der gesamte Kieferbereich, Zaehne, Pulpa und der Inhalt des

The use of a cine-technique in the MRT investigation of the temporo-mandibular joint. Die Anwendung der 'Cine-Technik' in der MRT-Diagnostik des Kiefergelenkes

Energy Technology Data Exchange (ETDEWEB)

Vogl, T.J.; Assal, J. (Univ. Muenchen, Radiologische Klinik Innenstadt (Germany)); Eberhard, D.; Weigl, P.; Randzio, J. (Univ. Muenchen, Klinik und Poliklinik fuer Kieferchirurgie (Germany))

1992-03-01

A new cine-technique in a prospective study using rapid gradient echo sequences was evaluated for the MRT investigation of the temporo-mandibular joint. A newly developed hydraulic apparatus was used to produce progressive opening of the jaw and MRT appearances were recorded during predetermined points of mandibular movement. The investigation included 16 normals and 34 patients. A modified gradient echo sequence was combined with an optimised surface coil or a special double coil and this provided good spatial resolution of the articular disc and of the muscular and bony structure. Amongst the abnormal findings were luxation of the disc (15 cases), tears in the disc (5 cases), late effects of internal derangements (12 cases) and condylar hypermobility (7 cases). The new cine-technique provides specific images in any chosen position of the mandible depending on the clinical disability of the patient. (orig.).

Possibilities of whole-body MRI for investigating musculoskeletal diseases; Moeglichkeiten der Ganzkoerper-MRT zur Diagnostik muskuloskelettaler Erkrankungen

Energy Technology Data Exchange (ETDEWEB)

Lenk, S.; Claussen, C.D.; Schlemmer, H.P. [Klinikum der Eberhardt-Karls-Universitaet Tuebingen, Abteilung fuer Diagnostische Radiologie (Germany); Fischer, S. [Universitaetsklinikum Tuebingen, Abteilung fuer Strahlentherapie (Germany); Koetter, I. [Universitaetsklinikum Tuebingen, Abteilung fuer Haematoonkologie (Germany)

2004-09-01

This contribution outlines possibilities and limitations of whole-body MRI for investigating musculoskeletal diseases. Benefits and drawbacks of the novel whole-body MRI technology are discussed and a possible whole-body MRI sequence protocol for musculoskeletal examinations is proposed. Muscle, joint and bone diseases are discussed in which the application of whole-body MRI may be of advantage. Particularly, polymyositis, muscledystrophy, rheumatoid arthritis, spondylitis ancylosans, multiple trauma, skeletal metastases, multiple myeloma and malignant lymphoma are mentioned. Whole-body MRI opens new advantages for the examination of multifocal musculoskeletal diseases. The clinical benefit of this method for particular diseases has to be evaluated in further studies, however. (orig.) [German] Dieser Beitrag gibt eine Uebersicht ueber die Moeglichkeiten und Limitationen der Ganzkoerper-MRT fuer die Diagnostik von Erkrankungen des muskuloskelettalen Systems. Es werden die Vor- und Nachteile der Ganzkoerper-MRT eroertert und ein Sequenzprotokoll fuer die muskuloskelettale Diagnostik vorgeschlagen. Auf Muskel-, Gelenk- und Knochenerkrankungen, bei denen der Einsatz der Ganzkoerper-MRT indiziert erscheint, dabei insbesondere Polymyositis, Muskeldystrophie, rheumatoide Arthritis, Spondylitis ankylosans, Polytrauma, Skelettmetastasen, Plasmozytom und das maligne Lymphom wird eingegangen. Die Ganzkoerper-MRT bietet neue Moeglichkeiten, insbesondere zur Ausbreitungsdiagnostik und Verlaufskontrolle multifokaler muskuloskelettaler Erkrankungen. Der klinische Nutzen dieser Methode fuer die einzelnen Erkrankungsentitaeten muss in weiteren Studien evaluiert werden. (orig.)

Typisierung von HLA-Klasse-II-Merkmalen mittels des TaqMan-Verfahrens

OpenAIRE

Tremmel, Matthias

2001-01-01

In Anlehnung an die konventionelle SSP-PCR-Methode wurde ein Low-Resolution-Panel mittels des TaqMan-Prinzips entwickelt und es wurde exemplarisch für DR4 und DR15/16 gezeigt, daß die auf dem 5 Nuklease-Assay beruhende Methode fähig ist, auch einzelne Punktmutationen voneinander zu unterscheiden. Das Grundprinzip dieser Methode basiert ähnlich dem der PCR-SSP auf dem Verfahren der PCR und auf dem Ausnutzen genetischer Unterschiede. So kommt es nur zu einer Amplifizierung wenn beide Primer spe...

Value of MRI in the diagnosis of stress urinary incontinence in the absence of organ descent; Beitrag der MRT in der Diagnostik der Stress-Harninkontinenz ohne begleitenden Descensus urogenitalis

Energy Technology Data Exchange (ETDEWEB)

Beyersdorff, D.; Taupitz, M.; Fischer, T.; Hamm, B. [Humboldt-Univ., Berlin (Germany). Inst. fuer Radiologie; Tunn, R.; Rieprich, M. [Humboldt-Univ., Berlin (Germany). Klinik fuer Gynaekologie und Geburtshilfe

2001-07-01

To detect pathomorphological changes of the pelvic floor, the vagina, and the urethra by MR imaging in patients with stress urinary incontinence in the absence of organ descent compared with findings in 10 healthy controls. Materials and Methods: The study included 10 healthy controls and 38 patients with stage II urinary incontinence showing no urge symptoms but a pathological stress profile on urodynamic testing. The subjects underwent MR imaging with a phased-array coil at 1.5 T in addition to urodynamic testing and gynecological examination. The following sequences were used: axial and coronal PD-weighted TSE sequences with a FOV of 20 cm and a section thickness of 4 mm; axial STIR sequence. Sagittal T{sub 2}-weighted HASTE sequences were acquired during pelvic floor contraction, relaxation, and straining maneuvers. Results: In 22/38 cases pathomorphological changes were found by MR imaging. The pathomorphological changes were classified as lateral defects (n = 14) if the musculofascial connection between the levator muscle and the lateral vaginal wall or the butterfly shape of the vagina was absent and as central (n = 16) if changes were detected in the urethral wall. Defects of the pelvic floor muscles were detected in 8 cases. No underlying changes were identified in 16/38 cases. Conclusion: In cases of female urinary incontinence, MR imaging of the pelvic floor can detect pathomorphological changes, which are difficult to identify by clinical examination. MR imaging currently does not allow the detection of morphological changes in all forms of female urinary stress incontinence. (orig.) [German] In einer prospektiven Studie sollen mittels MRT pathomorphologische Veraenderungen des Beckenbodens, der Vagina und der Urethra bei Patientinnen mit Stress-Harninkontinenz (HI) ohne begleitenden Descensus urogenitalis im Vergleich zu Patientinnen ohne HI untersucht werden. Material und Methoden: 38 Patientinnen mit Stress-HI im Stadium II wurden zusaetzlich zur

Physiological and technical limitations of functional magnetic resonance imaging (fMRI) - consequences for clinical use; Physiologische und technische Grenzen der funktionellen Magnetresonanztomographie und die damit verbundenen Konsequenzen fuer die klinische Anwendung

Energy Technology Data Exchange (ETDEWEB)

Wuestenberg, T. [Neurologische Klinik der Charite, Humboldt-Universitaet Berlin (Germany); Neurologische Klinik der Charite, Humboldt-Universitaet Berlin, Schumannstrasse 20/21, 10117, Berlin (Germany); Jordan, K. [Institut fuer Psychologie II, Otto-von-Guericke-Universitaet Magdeburg (Germany); Giesel, F.L. [Abteilung fuer onkologische Diagnostik und Therapie, Deutsches Krebsforschungszentrum Heidelberg (Germany); Villringer, A. [Neurologische Klinik der Charite, Humboldt-Universitaet Berlin (Germany)

2003-07-01

Functional magnetic resonance imaging (fMRI) is the most common noninvasive technique in functional neuroanatomy. The capabilities and limitations of the method will be discussed based on a short review of the current knowledge about the neurovascular relationship. The focus of this article is on current methodical and technical problems regarding fMRI-based detection and localization of neuronal activity. Main error sources and their influence on the reliability and validity of fMRI-methods are presented. Appropriate solution strategies will be proposed and evaluated. Finally, the clinical relevance of MR-based diagnostic methods are discussed. (orig.) [German] Die funktionelle Magnetresonanztomographie (fMRT) ist eines der wichtigsten Verfahren der funktionellen Neuroanatomie. Aufbauend auf einer kurzen Darstellung des aktuellen Wissensstands bzgl. des Zusammenhangs zwischen lokaler neuronaler Aktivitaet und haemodynamischer Reaktion werden ausgewaehlte Moeglichkeiten und Grenzen des Verfahrens fuer die klinische Anwendung diskutiert. Der Schwerpunkt liegt dabei auf der Darstellung der derzeitigen methodischen und technischen Einschraenkungen hinsichtlich einer fMRT-basierten Detektion und Lokalisierung neuronaler Aktivitaet. Es werden die Hauptfehlerquellen und ihre Auswirkungen auf die Reliabilitaet und Validitaet des Verfahrens erlaeutert und aktuelle Loesungsansaetze diskutiert. Abschliessend erfolgt eine Bewertung der aktuellen klinischen Relevanz funktioneller MR-Diagnosemethoden. (orig.)

MR imaging of the prostate; MRT der Prostata

Energy Technology Data Exchange (ETDEWEB)

Asbach, P.; Haas, M.; Hamm, B. [Charite Campus Benjamin Franklin, Klinik fuer Radiologie, Berlin (Germany)

2015-12-15

Prostate cancer is the most common form of cancer in men in Germany; however, there is a distinct difference between incidence and mortality. The detection of prostate cancer is based on clinical and laboratory testing using serum prostate-specific antigen (PSA) levels and transrectal ultrasound with randomized biopsy. Multiparametric MR imaging of the prostate can provide valuable diagnostic information for detection of prostate cancer, especially after negative results of a biopsy prior to repeat biopsy. In addition the use of MR ultrasound fusion-guided biopsy has gained in diagnostic importance and has increased the prostate cancer detection rate. The prostate imaging reporting and data system (PI-RADS) classification has standardized the reporting of prostate MRI which has positively influenced the acceptance by urologists. (orig.) [German] Das Prostatakarzinom ist in Deutschland die haeufigste Krebserkrankung des Mannes, wobei ein deutlicher Unterschied zwischen Inzidenz und Mortalitaet besteht. Die Detektion des Prostatakarzinoms basiert auf klinischer und laborchemischer Untersuchung (prostataspezifisches-Antigen[PSA]-Wert) sowie der transrektalen Ultraschalluntersuchung mit randomisierter Biopsie. Die multiparametrische MR-Tomographie kann zur Detektion des Prostatakarzinoms, insbesondere bei negativer Biopsie vor einer erneuten Biopsie wertvolle diagnostische Informationen liefern. Zudem wird zunehmend die MRT-Ultraschall-Fusionsbiopsie in der Diagnostik eingesetzt, wodurch die Detektionsrate des Prostatakarzinoms deutlich gesteigert werden kann. Mit Einfuehrung der PI-RADS-Klassifikation (Prostate Imaging-Reporting and Data System) konnte zudem eine Standardisierung der Befundung erreicht werden, was die Akzeptanz der MRT der Prostata in der Urologie erhoeht hat. (orig.)

Imaging diagnostics of the wrist: MRI and Arthrography/Arthro-CT; Bildgebende Diagnostik des Handgelenkes: MRT und Arthrographie/Arthro-CT

Energy Technology Data Exchange (ETDEWEB)

Klein, H.M.; Balas, R.; Neugebauer, F. [Radiologische Gemeinschaftspraxis, Betzdorf (Germany); Vrsalovic, V. [Handchirugie, Marienhospital Siegen, Siegen (Germany)

2002-02-01

Purpose: To evaluate the use of magnetic resonance imaging (MRI) compared with arthrography and arthro-CT (AG/ACT) in patients with wrist pain. Methods: MRI and arthrography/arthro-CT (AG/ACT) of the wrist joint were retrospectively evaluated in 346 patients over a three-year period. Imaging findings were correlated to surgical results (n=78) or clinical course in an at least 6-month follow-up. Results: For tears of the triangular fibrocartilage, arthrography, arthro-CT, and MRI demonstrated a sensitivity and specificity of more than 0.96. Only the positive predictive value was superior for arthrography/arthro-CT (0.99 and 0.98, respectively) compared with MRI (0.94). Arthrography was superior for functional diagnosis of scapho-lunate ligament tears (n=25). Ulno-lunate and ulno-triquetral ligament defects were demonstrated more exactly by arthrography. Traumatic osseous defects, particularly scaphoid fractures (n=33) and avascular necrosis (n=17), were better diagnosed using MRI. Conclusion: For suspected lesions of the triangular fibrocartilage complex, AG/ACT is slightly more reliable than MRI. However, MRI was found to be highly accurate in diagnosing TFC tears, and is superior to AG/ACT in detecting traumatic and vascular lesions of the wrist. (orig.) [German] Ziel: Die Untersuchung der diagnostischen Aussagekraft von Magnetresonanz-Tomographie (MRT), Arthrographie (AG) und Arthro-CT (ACT) bei Erkrankungen des Handgelenkes. Methodik: Insgesamt 346 Untersuchungen des Handgelenkes wurden fuer einen dreijaehrigen Beobachtungszeitraum retrospektiv ausgewertet. Es wurden 211 MRT, 151 Arthrographien (AG) und 126 Arthro-CT (ACT) durchgefuehrt. Alle Diagnosen wurden operativ (n=78) oder durch den klinischen Verlauf in einer 6-monatigen Nachbeobachtung gesichert. Ergebnisse: Fuer die Diagnostik von Laesionen des diskoulnaren Komplexes lag die Sensitivitaet und Spezifitaet von AG, ACT und MRT ueber 0,96. Lediglich der positive Vorhersagewert differierte, allerdings nicht

Intraoperative appearance of the resection area in brain-tumor operations in an open 0,5 MRT; Intraoperatives Erscheinungsbild des Resektionsbereichs bei Hirntumoroperationen in einem offenen 0,5-T-MRT

Energy Technology Data Exchange (ETDEWEB)

Dietrich, J. [Universitaetsklinik fuer Diagnostische Radiologie, Leipzig (Germany). Arbeitsbereich Neuroradiologie; Schneider, J.P.; Schulz, T. [Universitaetsklinik fuer Diagnostische Radiologie, Leipzig (Germany); Seifert, V.; Trantakis, C. [Universitaetsklinik fuer Neurochirurgie, Leipzig (Germany); Kellermann, S. [Leipzig Univ. (Germany). Abt. fuer Neuropathologie

1998-11-01

During MRI-controlled resection of brain tumors using an open MRI system, operation-induced alterations may occur, especially enhancement of the resection cavity wall. This may simulate tumor areas, resulting in false assessment of the resection or resection of non-tumorous areas. Based on 42 MRI- and biopsy-controlled brain tumor resections in an 0.5 T open MRI (Signa SP, GE), the appearance and origin of operation-induced reactions are analyzed. In our opinion, there is a superposition of preformed peritumoral reactions by operation-induced microcontusions. The beginning of the cavity wall enhancement needs at least 10-15 min. MRI-controlled analysis of the intraoperative steps by the neurosurgeon and neuroradiologist allows discrimination of operation-induced reactions from tumor areas and leads to safe operation. (orig.) [Deutsch] Bei der intraoperativen Kontrolle von Hirntumorresektionen in offenen MRT-Geraeten kann es zu operativ induzierten Veraenderungen, insbesondere Rand-enhancement-Zonen, kommen. Diese koennen Tumorreste vortaeuschen, so dass die Radikalitaet des Eingriffs unterschaetzt wird oder nicht tumortragende Hirnareale entfernt werden. Ergebnisse und Diskussion: Anhand von 42 in einem offenen 0,5-T-MRT (Signa SP, GE) vorgenommenen, biopsiekontrollierten Hirntumoroperationen werden Erscheinungsbild und Entstehungsweise der Randveraenderungen analysiert. Bei den haeufig vorzufindenden Rand-enhancement-Zonen handelt es sich um eine Ueberlagerung von praeformierten Tumorrandreaktionen mit Mikrokontusionen. Die Ausbildung dieser Veraenderungen braucht eine Mindestzeit von 10-15 min. Die staendige Analyse der die Tumorresektion begleitenden MRT-Kontrollen durch den Operateur und einen mit der Problematik vertrauten Radiologen gestattet in der Regel die Differenzierung der operativ induzierten Veraenderungen und erhoeht damit die Sicherheit des Eingriffs. (orig.)

Malignant degeneration of multiple cartilaginous exostosis. Diagnostic significance of MRT

International Nuclear Information System (INIS)

Bair, H.J.; Schmitt, R.; Moos, P.; Fellner, F.; Dvorak, O.; Rupprecht, H.; Lenz, M.

1997-01-01

In summary it can be said that diagnostic radiology, and particularly MRT, for evaluation of malignant degeneration of cartilaginous extoses is of high importance, also because of the difficulties posed by a biopsy for verification of malignancy. Cases of malignant cartilaginous extosis have a good prognosis at the early stages of the disease, when the extosis still is restricted to the focal region. (Orig./AJ) [de

Benign diseases of the mandible in MRI; Benigne Erkrankungen des Unterkiefers im MRT

Energy Technology Data Exchange (ETDEWEB)

Kress, B.; Sartor, K. [Universitaetsklinikum Heidelberg (Germany). Abt. Neuroradiologie; Gottschalk, A. [Bundeswehrkrankenhaus, Ulm (Germany). Abt. fuer Radiologie; Schmitter, M. [Universitaetsklinikum Heidelberg (Germany). Abt. fuer Zahnaerztliche Prothetik

2004-04-01

Diseases of the mandible affect the soft tissues aside from the osseous manifestation. This can be shown clearly and in great detail by magnetic resonance imaging (MRI). MRI is the gold standard in the diagnostic evaluation of any internal derangement of the temporomandibular joint. Dental MRI requires high resolution techniques and in some cases also intravenous administration of contrast material. These techniques allow delineation of the neurovascular bundle. In the past few years new indications were formulated, for example, the evaluation of the integrity of the inferior alveolar nerve in trauma and in radicular cysts. New quantitative methods now enable insights into the pathophysiology. The objective of this review is to communicate accepted indications for MRI of the mandible and to present innovative applications. (orig.) [German] Mandibulaere Erkrankungen beteiligen neben dem Knochen Weichteilstrukturen, die sich mit der MRT klar und detailreich darstellen lassen. In der bildgebenden Diagnostik der Binnenstoerung des Kiefergelenks (internal derangement) gilt die MRT als Goldstandard. Die MR-Tomographie des Unterkiefers erfordert hochaufloesende Techniken und bei besonderen Indikationen die intravenoese Kontrastmittelgabe. Diese Techniken erlauben es, das neurovaskulaere Buendel des Unterkiefers darzustellen. In den letzten Jahren sind neue Indikationsgebiete hinzugekommen, darunter solche, die die Unversehrtheit des N.alveolaris inferior bei Frakturen oder Raumforderungen des Unterkiefers ueberpruefen. Neue quantitative Verfahren geben mittlerweile Einblicke in Pathophysiologie. Ziel dieser Uebersichtsarbeit soll es sein, klassische Indikationen der Unterkiefer-MRT darzustellen und innovative Anwendungsmoeglichkeiten aufzuzeigen. (orig.)

New procedures. Comprehensive staging of lung cancer by MRI; Neue Verfahren. Umfassendes Staging des Lungenkarzinoms mit der MRT

Energy Technology Data Exchange (ETDEWEB)

Hintze, C. [Universitaetsklinikum Schleswig-Holstein, Campus Kiel, Klinik fuer Diagnostische Radiologie, Kiel (Germany); Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie (E010), Heidelberg (Germany); Dinkel, J. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie (E010), Heidelberg (Germany); Biederer, J. [Universitaetsklinikum Schleswig-Holstein, Campus Kiel, Klinik fuer Diagnostische Radiologie, Kiel (Germany); Heussel, C.P. [Thoraxklinik Heidelberg, Abteilung Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Puderbach, M. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie (E010), Heidelberg (Germany); Thoraxklinik Heidelberg, Abteilung Diagnostische und Interventionelle Radiologie, Heidelberg (Germany)

2010-08-15

Lung cancer staging according to the TNM system is based on morphological assessment of the primary cancer, lymph nodes and metastases. All aspects of this important oncological classification are measurable with MRI. Pulmonary nodules can be detected at the clinically relevant size of 4-5 mm in diameter. The extent of mediastinal, hilar and supraclavicular lymph node affection can be assessed at the same time. The predominant metastatic spread to the adrenal glands and spine can be detected in coronal orientation during dedicated MRI of the lungs. Search focused whole body MRI completes the staging. Various additional MR imaging techniques provide further functional and clinically relevant information during a single examination. In the oncological context the most important techniques are imaging of perfusion and tumor motion. Functional MRI of the lungs complements the pure staging and improves surgical approaches and radiotherapy planning. (orig.) [German] Das Staging des Lungenkarzinoms nach dem TNM-System basiert auf der morphologischen Einschaetzung des Primarius, der Lymphknoten und Metastasen. Alle Aspekte dieser onkologisch wichtigen Beurteilung lassen sich mit der MRT erfassen. Pulmonale Rundherde sind ab der klinisch relevanten Groesse von 4-5 mm Durchmesser sicher erkennbar. Die Groesse der mediastinalen, hilaeren und supraklavikulaeren Lymphknoten kann in einem Untersuchungsgang bestimmt werden. In der koronaren Schichtfuehrung der dedizierten MRT der Lunge werden die Bereiche der bevorzugten Metastasierung in Nebennieren und weite Teile der Wirbelsaeule miterfasst. Durch eine gezielte Ganzkoerper-MRT als Suchmethode wird der letzte Teil des Stagings erfuellt. Die MRT bietet vielfaeltige Moeglichkeiten, zusaetzliche funktionelle, klinisch relevante Informationen innerhalb einer Untersuchung zu erheben. Im onkologischen Kontext sind die Perfusionsbildgebung der Lunge und die Bewegungsabschaetzung der Tumoren am bedeutendsten. Die funktionelle MRT der

Clinical application of functional MRI for chronic epilepsy; Klinischer Einsatz der funktionellen MRT bei chronischer Epilepsie

Energy Technology Data Exchange (ETDEWEB)

Woermann, F.G.; Labudda, K. [Krankenhaus Mara, Epilepsiezentrum Bethel, Abteilung fuer Magentresonanztomographie, Bielefeld (Germany)

2010-02-15

Functional magnetic resonance imaging (fMRI) is frequently used in the presurgical diagnostic procedure of epilepsy patients, in particular for lateralization of speech and memory and for localization of the primary motor cortex to delineate the epileptogenic lesion from eloquent brain areas. fMRI is one of the non-invasive procedures in the presurgical diagnostic process, together with medical history, seizure semiology, neurological examination, interictal and ictal EEG, structural MRI, video EEG monitoring and neuropsychology. This diagnostic sequence leads either to the decision for or against elective epilepsy surgery or to the decision to proceed with invasive diagnostic techniques (Wada test, intra-operative or extra-operative cortical stimulation). It is difficult to evaluate the contribution of the fMRI test in isolation to the validity of the entire diagnostic sequence. Complications such as memory loss and aphasia in temporal lobe resections or paresis after frontal lobe resections are rare and rarely of disastrous extent. This further complicates the evaluation of the clinical relevance of fMRI as a predictive tool. In this article studies which investigated the concordance between fMRI and other diagnostic gold standards will be presented as well as the association between presurgical fMRI and postsurgical morbidity. (orig.) [German] Die funktionelle Magnetresonanztomographie (fMRT) wird im Rahmen der Epilepsiediagnostik vor epilepsiechirurgischen Eingriffen insbesondere zur Lateralisation von Sprache und Gedaechtnis und zur Lokalisation der Zentralregion eingesetzt, um den eloquenten Kortex von der epilepsieverursachenden, chirurgisch zugaenglichen Laesion abzugrenzen. Dabei ist die fMRT Teil einer Sequenz nichtinvasiver klinischer Tests (Anamnese, Anfall-Semiologie, neurologischer Status, interiktales und iktales EEG, strukturelles MRT, Video-EEG-Monitoring, Neuropsychologie). Das Ergebnis dieser Sequenz ist die Entscheidung fuer oder gegen einen

Uterine cervical cancer. Preoperative staging with magnetic resonance imaging; Zervixkarzinom. Praeoperatives Staging mittels Magnetresonanztomographie

Energy Technology Data Exchange (ETDEWEB)

Collettini, F.; Hamm, B. [Charite-Universitaetsmedizin Berlin, Campus Charite Mitte, Klinik fuer Radiologie, Berlin (Germany)

2011-07-15

The treatment of uterine cervical carcinoma is largely dependent on the tumor stage. Despite significant inaccuracies in the clinical examination, uterine cervical cancer remains the only gynecological form of cancer still largely staged according to clinical findings. Although imaging is still not included in the staging the recently published revised FIGO (Federation International de Gynecologie et d'Obstetrique) system encourages the use of modern cross-sectional imaging (magnetic resonance imaging MRI and computed tomography CT). Due to its high soft tissue contrast MRI allows excellent non-invasive assessment of the cervix with direct tumor delineation as well as assessment of the prognosis based on morphological factors. Studies in the literature report an accuracy of 93% for MRI in the preoperative assessment of tumor size and in the differentiation of operable from advanced cervical cancer. Therefore MRI is considered to be the optimal modality for diagnostic evaluation starting from FIGO stage IB1, for radiation therapy planning, and for exclusion of recurrence in follow-up. In this paper we give an overview of the role of magnetic resonance imaging in preoperative staging of uterine cervical cancer. (orig.) [German] Die Therapieplanung beim Zervixkarzinom ist weitgehend von der Stadieneinteilung nach FIGO (Federation International de Gynecologie et d'Obstetrique) abhaengig, die trotz erheblicher Ungenauigkeiten bei der klinischen Stadieneinteilung weiterhin aufgrund klinischer Untersuchungsbefunde erfolgt. Obwohl bildgebende Verfahren nach wie vor fuer die Stadieneinteilung nicht vorgesehen sind, wird im kuerzlich erschienen revidierten Stagingsystem der FIGO zum ersten Mal die Verwendung moderner Schnittbilddiagnostik (MRT und CT) befuerwortet. Die MRT ermoeglicht dank ihres hohen Weichteilkontrasts ein ausgezeichnetes nichtinvasives Staging des Zervixkarzinoms mit direkter Tumordarstellung sowie einer Prognoseabschaetzung anhand

Combined PET/MRI in cerebral and paediatric diagnostics; Kombinierte PET/MRT-Diagnostik bei zerebralen und paediatrischen Fragestellungen

Energy Technology Data Exchange (ETDEWEB)

Pfluger, T.; Vollmar, C.; Porn, U.; Schmid, R.; Dresel, S.; Leinsinger, G.; Schmid, I.; Winkler, P.; Fischer, S.; Hahn, K. [Klinik und Poliklinik fuer Nuklearmedizin, Ludwig-Maximilians-Univ. Muenchen (Germany)

2002-07-01

The aim of this overview is presentation of MRI and PET as synergistic modalities for combined analysis of morphology and function. For operative planning in epilepsy surgery, definition of the epileptogenic focus based on functional PET diagnostics and morphological MRI is decisive. For staging and follow-up examinations in oncology, MRI should be complemented by PET for the assessment of tumor vitality. In paediatric oncology patients we could demonstrate a therapy relevant increase of sensitivity/specificity with combined PET/MRI in contrast to single modalities. In the brain, full spectrum of digital image registration and three-dimensional reconstruction should be used. In extracranial cases, image fusion is disturbing due to a partial loss of image information of single modalities by the fusion process. (orig.) [German] Ziel dieser Uebersicht ist die Darstellung der MRT und PET als synergistische Verfahren zur Analyse von Morphologie und Funktion. Zur Resektionsplanung im Rahmen der Epilepsiechirurgie ist die Definition des Epilepsiefokus anhand der funktionellen PET-Diagnostik und die exakte Kenntnis der zerebralen Morphologie aus der MRT ganz entscheidend. Im Rahmen des onkologischen Stagings und bei Verlaufskontrollen ist wegen der geringeren Spezifitaet der MRT die additive PET zur Beurteilung der Tumorvitalitaet erforderlich. Anhand eines paediatrisch-onkologischen Patientengutes konnten wir zeigen, dass mit der kombinierten PET/MRT-Diagnostik eine therapierelevante Steigerung der Sensitivitaet/Spezifitaet gegenueber den Einzeluntersuchungen moeglich ist. Bei zerebralen Fragestellungen sollte das gesamte Spektrum der digitalen Bildfusion mit direkter Ueberlagerung mehrerer Modalitaeten und anschliessender dreidimensionaler Rekonstruktion ausgeschoepft werden. Bei extrakraniellen Fragestellungen ist die direkte Bildueberlagerung eher hinderlich, da die Bildinformation der Einzelmodalitaeten durch die Fusion teilweise verloren geht. (orig.)

Konferenz Stadtmusikgeschichte in Mittel- und Osteuropa. Die Musik der Religionsgemeinschaften um 1900. Lipsko, 5.-6. listopadu 2004

Czech Academy of Sciences Publication Activity Database

Freemanová, Michaela

2004-01-01

Roč. 30, č. 4 (2004), s. 647-648 ISSN 1335-2458. [Konferenz Stadtmusikgeschichte in Mittel- und Osteuropa. Die Musik der Religionsgemeinschaften um 1900. Leipzig, 04.11.05-04.11.06] Institutional research plan: CEZ:AV0Z9058907 Keywords : music * religious community * 19th century Subject RIV: AL - Art, Architecture, Cultural Heritage

Molecular imaging of head and neck cancers. Perspectives of PET/MRI; Molekulare Bildgebung bei Kopf-ï]¿Hals-Tumoren. Perspektive der PET-MRT

Energy Technology Data Exchange (ETDEWEB)

Stumpp, P.; Kahn, T. [Universitaetsklinikum Leipzig AoeR, Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Leipzig (Germany); Purz, S.; Sabri, O. [Universitaetsklinikum Leipzig, Klinik und Poliklinik fuer Nuklearmedizin, Leipzig (Germany)

2016-07-15

The {sup 18}F-fluorodeoxyglucose positron emission tomography-computed tomography ({sup 18}F-FDG-PET/CT) procedure is a cornerstone in the diagnostics of head and neck cancers. Several years ago PET-magnetic resonance imaging (PET/MRI) also became available as an alternative hybrid multimodal imaging method. Does PET/MRI have advantages over PET/CT in the diagnostics of head and neck cancers ?The diagnostic accuracy of the standard imaging methods CT, MRI and PET/CT is depicted according to currently available meta-analyses and studies concerning the use of PET/MRI for these indications are summarized. In all studies published up to now PET/MRI did not show superiority regarding the diagnostic accuracy in head and neck cancers; however, there is some evidence that in the future PET/MRI can contribute to tumor characterization and possibly be used to predict tumor response to therapy with the use of multiparametric imaging. Currently, {sup 18}F-FDG-PET/CT is not outperformed by PET/MRI in the diagnostics of head and neck cancers. The additive value of PET/MRI due to the use of multiparametric imaging needs to be investigated in future research. (orig.) [German] Die {sup 18}F-Fluordesoxyglukose-Positronenemissionstomographie-Computertomographie ({sup 18}F-FDG-PET-CT) hat ihren festen Stellenwert in der Diagnostik von Kopf-Hals-Tumoren. Seit einigen Jahren ist die PET-MRT als weitere hybride Bildgebungsmodalitaet verfuegbar. Bringt die PET-MRT Fortschritte bei der Diagnostik von Kopf-Hals-Tumoren ?Darstellung der diagnostischen Genauigkeit der bisherigen Bildgebungsmethoden CT, MRT und PET-CT anhand von Metaanalysen und Zusammenfassung der bisherigen Publikationen zur PET-MRT auf diesem Gebiet. Die PET-MRT zeigt in allen bisherigen Studien keine Ueberlegenheit bzgl. der diagnostischen Genauigkeit von Kopf-Hals-Tumoren. Sie kann jedoch durch die multiparametrische Diagnostik perspektivisch Beitraege zur Tumorcharakterisierung und damit moeglicherweise Voraussagen zum

Haemophilic arthropathy of the knee. Gd-DTPA enhanced MRT. Clinical and radiological correlation; Haemophile Arthropathie des Kniegelenkes. Gd-DTPA-verstaerkte MRT: klinische und roentgenologische Korrelation

Energy Technology Data Exchange (ETDEWEB)

Naegele, M. [Radiologische Universitaetsklinik, Bonn (Germany); Kunze, V. [Radiologische Universitaetsklinik, Bonn (Germany); Hamann, M. [Radiologische Universitaetsklinik, Bonn (Germany); Eickhoff, H. [Orthopaedische Klinik, Krankenhaus Troisdorf (Germany); Koch, W. [Orthopaedische Klinik, Krankenhaus Troisdorf (Germany); Oldenburg, J. [Inst. fuer Experimentelle Haematologie und Transfusionsmedizin, Bonn (Germany); Reiser, M. [Muenchen Univ. (Germany). Inst. fuer Radiologische Diagnostik; Steudel, A. [Radiologische Universitaetsklinik, Bonn (Germany)

1994-02-01

17 patients with hemophilic arthropathy of the knee joint were studied with static and dynamic MRT before and after i.v. bolus injection of Gadolinium-DTPA (0,1 mmol/kg body weight). After contrast enhancement, synovial proliferations exhibited an increase of signal intensity (SI) of FFE and SE images of 47.7% and 37.4% respectively, whereas muscle and fatty tissue, tendons, bone marrow and joint effusion revealed only minor increase in SI. The gradient of signal intensity (ratio SI/time) of pannus was 39,6% min. Gd-DTPA enhanced MRI studies delineate and quantify the synovial proliferations in hemophilic arthropathy. Dynamic studies in hemophilic arthropathy do not provide qualitative assessment of the inflammatory process. (orig.) [Deutsch] Es wurden 17 Patienten mit einer haemophilen Arthropathie der Kniegelenke mit der statischen und dynamischen MRT vor und nach i.v. Bolusgabe von Gadolinium-DTPA (0,1 mmol/kg KG) untersucht. Nach Kontrastmittelgabe konnte ein Anstieg der Signalintensitaet des Pannus von 37,4% auf SE- und von 47,7% auf FFE-Aufnahmen gemessen werden. Der Gradient des Signalintensitaetsanstieges (%/Zeit) lag fuer Pannus bei 39,6%/min. Die Kontrastmittelgabe steigerte die Abgrenzbarkeit des Pannus von Gelenkerguss und den Gelenkbinnenstrukturen. Begleitend durchgefuehrte klinische und roentgenologische Bewertungen des Schweregrades der Arthropathie korrelierten nicht mit dem Signalintensitaetsverhalten des Pannus nach Kontrastmittelgabe. (orig.)

Computer-assisted operational planning for pediatric abdominal surgery. 3D-visualized MRI with volume rendering; Die computerassistierte Operationsplanung in der Abdominalchirurgie des Kindes. 3D-Visualisierung mittels ''volume rendering'' in der MRT

Energy Technology Data Exchange (ETDEWEB)

Guenther, P.; Holland-Cunz, S.; Waag, K.L. [Universitaetsklinikum Heidelberg (Germany). Kinderchirurgie; Troeger, J. [Universitaetsklinikum Heidelberg, (Germany). Paediatrische Radiologie; Schenk, J.P. [Universitaetsklinikum Heidelberg, (Germany). Paediatrische Radiologie; Universitaetsklinikum, Paediatrische Radiologie, Heidelberg (Germany)

2006-08-15

Exact surgical planning is necessary for complex operations of pathological changes in anatomical structures of the pediatric abdomen. 3D visualization and computer-assisted operational planning based on CT data are being increasingly used for difficult operations in adults. To minimize radiation exposure and for better soft tissue contrast, sonography and MRI are the preferred diagnostic methods in pediatric patients. Because of manifold difficulties 3D visualization of these MRI data has not been realized so far, even though the field of embryonal malformations and tumors could benefit from this. A newly developed and modified raycasting-based powerful 3D volume rendering software (VG Studio Max 1.2) for the planning of pediatric abdominal surgery is presented. With the help of specifically developed algorithms, a useful surgical planning system is demonstrated. Thanks to the easy handling and high-quality visualization with enormous gain of information, the presented system is now an established part of routine surgical planning. (orig.) [German] Komplexe Operationen bei ausgepraegten pathologischen Veraenderungen anatomischer Strukturen des kindlichen Abdomens benoetigen eine exakte Operationsvorbereitung. 3D-Visualisierung und computerassistierte Operationsplanung anhand von CT-Daten finden fuer schwierige chirurgische Eingriffe bei Erwachsenen in zunehmendem Masse Anwendung. Aus strahlenhygienischen Gruenden und bei besserer Weichteildifferenzierung ist jedoch neben der Sonographie die Magnetresonanztomographie (MRT) bei Kindern das Diagnostikum der Wahl. Die 3D-Visualisierung dieser MRT-Daten ist dabei jedoch aufgrund vielfaeltiger Schwierigkeiten bisher nicht durchgefuehrt worden, obwohl sich das Gebiet embryonaler Fehlbildungen und Tumoren geradezu anbietet. Vorgestellt wird eine weiterentwickelte und an die Fragestellungen der abdominellen Kinderchirurgie angepasste, sehr leistungsstarke raycastingbasierte 3D-volume-rendering-Software (VG Studio Max 1

NMR imaging of the vertebral column and the spinal canal. 2. rev. and enl. ed.; MRT der Wirbelsaeule und des Spinalkanals

Energy Technology Data Exchange (ETDEWEB)

Forsting, Michael [Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie; Uhlenbrock, Detlev [St.-Josefs-Hospital, Dortmund (Germany). MVZ Radiologie, Nuklearmedizin und Strahlentherapie; Wanke, Isabel [Privatklinikengruppe Hirslanden, Zurich (Switzerland); Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie

2009-07-01

The book on the MRT (magnetic resonance tomography) of the vertebral cord and spinal canal covers the following topics: physics fundamentals and application; malformation of the spinal canal; degenerative vertebral column diseases; vertebral column and spinal canal carcinomas; inflammatory diseases of the vertebral column and the spinal canal; applicability of MRT in case of acute spinal cord traumata; vascular diseases of the spinal canal.

Acquired CNS lesions in fetal MRI; Erworbene ZNS-Laesionen im fetalen MRT

Energy Technology Data Exchange (ETDEWEB)

Reith, W.; Pogledic, I. [Universitaetsklinikum des Saarlandes, Homburg/Saar, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany)

2013-02-15

Acquired central nervous system (CNS) lesions are often subtle; therefore, the prenatal diagnosis of these lesions is extremely important. The fetal ultrasound examination and magnetic resonance imaging (MRI) are two important imaging methods that give an insight into these types lesions. The method of choice during pregnancy is still fetal ultrasound; however, fetal MRI is important when there are certain pathologies, e.g. periventricular leukomalacia (PVL) or malformations of the vein of Galen. In this manner clinicians can plan further therapy after childbirth in advance (e.g. cerebral angiography or embolization). (orig.) [German] Die erworbenen ZNS-Laesionen sind oft subtil, und eine praezise praenatale Diagnostik ist in diesen Faellen besonders wichtig. Die fetale Sonographie und das fetale MRT koennen hierzu einen relevanten Beitrag leisten. Die Sonographie ist immer noch die Untersuchungsmethode der Wahl waehrend der Schwangerschaft. Insbesondere bei bestimmten Pathologien wie der periventrikulaeren Leukomalazie (PVL) oder einer V. -Galeni-Malformation ist das fetale MRT sehr hilfreich, um nach der Geburt die entsprechenden weitergehenden Massnahmen, wie eine zerebrale Angiographie und Embolisation, fruehzeitig zu planen. (orig.)

Neurogenic myopathies and imaging of muscle denervation; Neurogene Myopathien und Bildgebung der Muskeldenervation

Energy Technology Data Exchange (ETDEWEB)

Wolf, M. [Universitaetsklinikum Heidelberg, Abteilung fuer Neuroradiologie, Heidelberg (Germany); Wolf, C. [Reha-Zentrum Gernsbach, Neurologie, Gernsbach (Germany); Weber, M.A. [Universitaetsklinikum Heidelberg, Abteilung fuer Diagnostische und Interventionelle Radiologie, Heidelberg (Germany)

2017-12-15

, chronische Kompressionen sowie neurodegenerative, inflammatorische, metabolische und neoplastische Prozesse. Anamnese, klinisch-neurologische Untersuchung und elektrophysiologische Tests einschliesslich Elektromyographie (EMG) und Testung der Nervenleitgeschwindigkeit sind notwendig. Die EMG stellt den Goldstandard in der Diagnose von Muskeldenervierung dar. Ergaenzende bildgebende Methoden, vor allem die Magnetresonanztomographie (MRT) koennen teils sinnvolle Informationen liefern. Bei akuter und subakuter Denervierung weist die Muskulatur in der MRT Oedeme, ADC(''apparent diffusion coefficient'')-Erhoehung und gesteigerte Perfusion auf. Die mittels MRT nachweisbaren Veraenderungen denervierter Muskulatur sind relativ unspezifisch, erreichen aber eine vergleichbar hohe Sensitivitaet wie die EMG. Mittels dezidierter MR-Neurographie kann oft auch die ursaechliche Schaedigung des/der innervierenden Nerven visualisiert werden. Abgesehen von der mit der EMG vergleichbaren Sensitivitaet eignet sich die MRT zur Beurteilung von Muskeln, die einer Nadelelektromyographie nicht zugaenglich sind. Aufgrund ihres nichtinvasiven Charakters ist die MRT auch ideal fuer Verlaufsuntersuchungen. Oft ergaenzt die MRT die Diagnostik neurogener Myopathien sinnvoll. Ausmass und Verteilungsmuster der muskulaeren Veraenderungen lassen haeufig auf die Lokalisation der ursaechlichen Nervenschaedigung schliessen. Oft ermoeglichet die MRT eine korrekte Diagnosestellung oder zumindest eine Eingrenzung moeglicher Differenzialdiagnosen. (orig.)

Asymptotic Analysis in MIMO MRT/MRC Systems

Directory of Open Access Journals (Sweden)

Zhou Quan

2006-01-01

Full Text Available Through the analysis of the probability density function of the squared largest singular value of a complex Gaussian matrix at the origin and tail, we obtain two asymptotic results related to the multi-input multi-output (MIMO maximum-ratio-transmission/maximum-ratio-combining (MRT/MRC systems. One is the asymptotic error performance (in terms of SNR in a single-user system, and the other is the asymptotic system capacity (in terms of the number of users in the multiuser scenario when multiuser diversity is exploited. Similar results are also obtained for two other MIMO diversity schemes, space-time block coding and selection combining. Our results reveal a simple connection with system parameters, providing good insights for the design of MIMO diversity systems.

MRI in neuromuscular disorders; MRT bei neuromuskulaeren Erkrankungen

Energy Technology Data Exchange (ETDEWEB)

Fischmann, Arne [Klinik St. Anna, Luzern (Switzerland). Inst. fuer Radiologie und Nuklearmedizin; Fischer, Dirk [Kantonsspital Bruderholz (Switzerland)

2014-03-15

Neuromuscular disorders are caused by damage of the skeletal muscles or supplying nerves, in many cases due to a genetic defect, resulting in progressive disability, loss of ambulation and often a reduced life expectancy. Previously only supportive care and steroids were available as treatments, but several novel therapies are under development or in clinical trial phase. Muscle imaging can detect specific patterns of involvement and facilitate diagnosis and guide genetic testing. Quantitative MRT can be used to monitor disease progression either to monitor treatment or as a surrogate parameter for clinical trails. Novel imaging sequences can provide insights into disease pathology and muscle metabolism. (orig.)

Magnetic resonance tomography and ultrasound in rheumatology; MRT und Sonographie in der Rheumatologie

Energy Technology Data Exchange (ETDEWEB)

Kainberger, F. [Universitaetsklinik fuer Radiodiagnostik, Ludwig-Boltzmann-Inst. fuer Physikalische und Radiologische Tumordiagnostik, Wien (Austria); Czerny, C. [Universitaetsklinik fuer Radiodiagnostik, Ludwig-Boltzmann-Inst. fuer Physikalische und Radiologische Tumordiagnostik, Wien (Austria); Trattnig, S. [Universitaetsklinik fuer Radiodiagnostik, Ludwig-Boltzmann-Inst. fuer Physikalische und Radiologische Tumordiagnostik, Wien (Austria); Lack, W. [Universitaetsklinik fuer Orthopaedie, Wien (Austria); Machold, K. [Universitaetsklinik fuer Innere Medizin III, Wien (Austria). Abt. fuer Rheumatologie; Graninger, W. [Universitaetsklinik fuer Innere Medizin III, Wien (Austria). Abt. fuer Rheumatologie

1996-08-01

Technical innovations and software improvements in magnetic resonance imaging (MRI) and high-resolution sonography (US) have definitely influenced the diagnostic imaging of rheumatic diseases. For MRI, improvements in surface coils, dedicated low-field systems (0.2 T), and software improvements (shorter acquisition times and refinements of fat suppressing techniques) must be mentioned. For sonography, the main innovations concern the development of higher transducer frequencies (7-15 Mhz) and power Doppler imaging. Clinical evaluations have shown that MRI and US are most useful in cases of suspected rheumatic disease with negative plain film radiographs and for documenting the course of the disease, diagnosing of early rheumatoid arthritis, making a differential diagnosis in clinically unclear rheumatic diseases, investigating vascularization, and quantifying pannus formation. In order to improve diagnostic efficacy the role of MRI and US in the management of patients with rheumatic disease should be reconsidered. (orig.) [Deutsch] Technische Innovationen in Hard- und Software von Magnetresonanztomographie (MRT) und Sonographiegeraeten haben die bildgebende Diagnostik in der Rheumatologie massgeblich beeinflusst (Verbesserungen der Oberflaechenspulen mit hohen Gradientenfeldern, dedizierte Niederfeldgeraete, Softwareverbesserungen in Form von kuerzeren Aquisitionszeiten und Verfeinerungen in der Fettunterdrueckung, hoehere Transducerfrequenzen zwischen 7 und 15 Mhz, Powerdopplerverfahren). Fuer die klinische Anwendung bedeutet dies, dass MRT und Sonographie als bildgebende Zusatzverfahren nach der Anfertigung konventioneller Roentgenaufnahmen anzuwenden sind, wenn diese unauffaellige Resultate ergeben oder spezielle Fragen zur Schwere des Krankheitsprozesses bzw. von Folgeerscheinungen zu beantworten sind. Im besonderen betrifft dies den Nachweis der Frueharthritis, die Differentialdiagnose klinisch nicht klar einzuordnender Krankheitsbilder und die Bestimmung des

Pre- and post-operative evaluation of ventricular function, muscle mass and valve morphology by MR tomography in Ebstein's anomaly; Prae- und postoperative Beurteilung der ventrikulaeren Funktion, Muskelmasse und Klappenmorphologie bei der Ebstein-Anomalie mit der Magnetresonanztomographie

Energy Technology Data Exchange (ETDEWEB)

Gutberlet, M.; Oellinger, H.; Amthauer, H.; Hoffmann, T.; Felix, R. [Charite-Campus Virchow, Berlin (Germany). Klinik fuer Strahlenheilkunde; Ewert, P.; Nagdyman, N.; Lange, P. [Deutsches Herzzentrum Berlin (Germany). Abt. fuer Angeborene Herzfehler/Kinderkardiologie; Hetzer, R. [Deutsches Herzzentrum Berlin (Germany). Abt. fuer Herz-, Thorax- und Gefaesschirurgie

2000-05-01

Purpose: To evaluate the value of MRT with spin echo (SE) and CINE gradient echo (GE) sequences for the pre- and postoperative assessment of patients with Ebstein's anomaly. Methods: Twelve patients within the ages of four to 49 years (mean 22{+-}12 years) were examined pre- (n=5) or postoperatively (n=7) after tricuspid valve reconstruction with a 1.5 T scanner. For the anatomical assessment, an ECG-gated transverse SE-sequence, for the assessment of valve morphology and function as well as for volumetry a CINE GE-sequence with retrospective gating was used. With the use of the multislice-multiphase technique, after summing up the manually outlined epi- and endocardial areas, endsystolic (ESV) and enddiastolic volumes (EDV), ejection fraction (EF), stroke volume (SV), and muscle mass (MM) were calculated for both ventricles. Results: The differentiation of the displaced parts of the tricuspid valve (TV) was insufficient with static SE, but was possible in all patients with CINE-MRT. Like in Doppler echocardiography, a qualitative assessment of tricuspid insufficiency was possible in CINE-MRT, the mean incompetence grade preoperative was 1.8 ({+-}0.8), postoperative 0.7 ({+-}0.5). The mean RV-EF in the preoperative group was 41.8% ({+-}6.4), in the postoperative group 47.9% ({+-}10.6), the mean LV-EF preoperative 47.4% ({+-}8.5%), postoperative 63,0% ({+-}9.4). Conclusion: CINE-MRT should rather be used than SE for the assessment of valve morphology. EF, muscle mass and tricuspid incompetence can also be calculated pre- and postoperative with CINE-MRT. (orig.) [German] Zielsetzung: Zu ermitteln, welchen Beitrag die MRT mit der Spin-Echo-(SE) bzw. CINE-Gradienten-Echo-Sequenz (GE) zur prae- und postoperativen Beurteilung bei Patienten mit Ebstein-Anomalie leisten kann. Material und Methode: Es wurden 12 Patienten im Alter zwischen 4 und 49 Jahren (im Mittel 22{+-}12 Jahre) prae- (n=5) oder postoperativ (n=7) nach einer Trikuspidalklappenkonstruktion an einem 1

Clinical evaluation of female pelvic tumors. Application fields of integrated PET/MRI; Lokal- und Ganzkoerperdiagnostik weiblicher Beckentumore. Anwendungsfelder der integrierten PET-MRT

Energy Technology Data Exchange (ETDEWEB)

Grueneisen, J.; Umutlu, L. [Universitaetsklinikum Essen, Institut fuer diagnostische und interventionelle Radiologie und Neuroradiologie, Essen (Germany)

2016-07-15

Integrated positron emission tomography (PET) and magnetic resonance imaging (MRI) scanning has recently become established in clinical imaging. Various studies have demonstrated the great potential of this new hybrid imaging procedure for applications in the field of oncology and the diagnostics of inflammatory processes. With initial studies demonstrating the feasibility and high diagnostic potential of PET/MRI comparable to PET-computed tomography (CT), the focus of future studies should be on the identification of application fields with a potential diagnostic benefit of PET/MRI over other established diagnostic tools. Both MRI and PET/CT are widely used in the diagnostic algorithms for malignancies of the female pelvis. A simultaneous acquisition of PET and MRI data within a single examination provides complementary information which can be used for a more comprehensive evaluation of the primary tumor as well as for whole body staging. Therefore, the aim of this article is to outline potential clinical applications of integrated PET/MRI for the diagnostic work-up of primary or recurrent gynecological neoplasms of the female pelvis. (orig.) [German] Integrierte Positronenemissionstomographie-Magnetresonanztomographen (PET-MRT) stehen seit wenigen Jahren fuer die klinische Diagnostik zur Verfuegung. Diverse Arbeiten konnten bereits das grosse Potenzial dieser neuen hybriden Bildgebungsmodalitaet zur Anwendung in der onkologischen und inflammatorischen Diagnostik aufzeigen. Nachdem initiale Studien die Durchfuehrbarkeit und diagnostische Vergleichbarkeit der PET-MRT zur etablierten PET-Computertomographie (PET-CT) gezeigt haben, sollte fuer eine Implementierung in der Routinediagnostik der Fokus zukuenftiger Studien darin liegen, eindeutige Indikationen zu definieren, in denen die simultane PET-MRT-Bildgebung einen definitiven Vorteil verglichen mit den etablierten diagnostischen Verfahren bietet. Sowohl die MRT als auch die PET-CT finden bereits eine

Simultaneous whole-body PET-MRI in pediatric oncology. More than just reducing radiation?; Simultane Ganzkoerper-PET-MRT in der paediatrischen Onkologie. Mehr als nur Strahlenersparnis

Energy Technology Data Exchange (ETDEWEB)

Gatidis, S.; Gueckel, B.; Schaefer, J.F. [Universitaet Tuebingen, Radiologische Klinik, Diagnostische und Interventionelle Radiologie, Tuebingen (Germany); Fougere, C. la [Universitaet Tuebingen, Radiologische Klinik, Nuklearmedizin, Tuebingen (Germany); Schmitt, J. [Universitaet Tuebingen, Abteilung fuer Praeklinische Bildgebung und Radiopharmazie, Werner Siemens Imaging Center, Tuebingen (Germany)

2016-07-15

Diagnostic imaging plays an essential role in pediatric oncology with regard to diagnosis, therapy-planning, and the follow-up of solid tumors. The current imaging standard in pediatric oncology includes a variety of radiological and nuclear medicine imaging modalities depending on the specific tumor entity. The introduction of combined simultaneous positron emission tomography (PET) and magnetic resonance imaging (MRI) has opened up new diagnostic options in pediatric oncology. This novel modality combines the excellent anatomical accuracy of MRI with the metabolic information of PET. In initial clinical studies, the technical feasibility and possible diagnostic advantages of combined PET-MRI have been in comparison with alternative imaging techniques. It was shown that a reduction in radiation exposure of up to 70 % is achievable compared with PET-CT. Furthermore, it has been shown that the number of imaging studies necessary can be markedly reduced using combined PET-MRI. Owing to its limited availability, combined PET-MRI is currently not used as a routine procedure. However, this new modality has the potential to become the imaging reference standard in pediatric oncology in the future. This review article summarizes the central aspects of pediatric oncological PET-MRI based on existing literature. Typical pediatric oncological PET-MRI cases are also presented. (orig.) [German] Die bildgebende Diagnostik spielt in der paediatrischen Onkologie eine zentrale Rolle fuer die Diagnose, die Therapieplanung und die Nachsorge solider Tumoren. Der aktuell bildgebende Standard in der paediatrischen Onkologie sieht - abhaengig von der vorliegenden Tumorentitaet - eine Kombination mehrerer radiologischer und nuklearmedizinischer Verfahren vor. Die Einfuehrung der simultanen Positronenemissionstomographie(PET)-Magnetresonanztomographie (MRT) hat neuartige Moeglichkeiten der Diagnostik in der paediatrischen Onkologie eroeffnet. Dabei kombiniert dieses neue Verfahren die

Imaging technique and current status of valvular heart disease using cardiac MRI; Untersuchungstechniken und Stellenwert der MRT bei der Diagnostik von Herzklappenerkrankungen

Energy Technology Data Exchange (ETDEWEB)

Lotz, J.; Sohns, J.M. [Universitaetsmedizin Goettingen, Georg-August-Universitaet, Institut fuer Diagnostische und Interventionelle Radiologie, Goettingen (Germany)

2013-10-15

The main indications for cardiac magnetic resonance imaging (MRI) in the evaluation of valvular heart disease are pathologies of the aortic and pulmonary valve. For mitral and tricuspid valve pathologies MRI is not the first line modality as these are usually well visualized by echocardiography. The advantages of MRI in valvular heart disease are a high reliability in the evaluation of ventricular volumes and function as well as the assessment of the perivalvular arterial or atrial structures. This reliability and the limitless access to any imaging plane partially compensates for the lower temporal and spatial resolution in comparison to echocardiography. In patients with congenital heart disease, cardiac MRI is established as a valuable diagnostic tool in daily clinical management, especially for the evaluation of pulmonary valve defects. Nevertheless, echocardiography remains the first-line diagnostic imaging tool for the foreseeable future. (orig.) [German] Die Untersuchung der Herzklappen in der MRT umfasst derzeit v. a. die Aorten- und Pulmonalisklappe. Pathologien der atrioventrikulaeren Klappen bilden demgegenueber nur selten die zentrale Fragestellung einer kardialen MRT-Untersuchung, da diese normalerweise einer echokardiographischen Untersuchung gut zugaenglich sind. Die Staerke der MRT ist die hohe Zuverlaessigkeit, mit der neben der Klappenmorphologie und -funktion die Funktionsparameter des jeweiligen Ventrikels und die Morphologie der nachgeschalteten Arterien bestimmt werden koennen. Dadurch kann die MRT die prinzipielle Schwaeche in der Orts- und Zeitaufloesung gegenueber der Echokardiographie teilweise kompensieren. Bei Patienten mit kongenitalen Herzvitien ist die MRT-basierte Klappendiagnostik fester Bestandteil des klinischen Managements. Das gilt besonders fuer die Evaluation der Pulmonalisklappe. Die Echokardiographie bleibt absehbar die Modalitaet der ersten Wahl fuer die Klappendiagnostik am Herzen. (orig.)

MRI in cardiac sarcoidosis and amyloidosis; MRT bei kardialer Sarkoidose und Amyloidose

Energy Technology Data Exchange (ETDEWEB)

Bauner, K.U. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Wintersperger, B. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); University of Toronto, Department of Medical Imaging, Toronto General Hospital, Toronto, ON (Canada)

2013-01-15

Sarcoidosis and amyloidosis are both multisystem disorders, which may involve the heart; however, isolated cardiac disease is rare. Diagnosis of cardiac sarcoidosis and amyloidosis is crucial because the patient prognosis is dependent on cardiac involvement and early treatment. Echocardiography is the first line imaging modality in the diagnostic work-up of both diseases, possibly giving hints towards the correct diagnosis. Besides myocardial biopsy and radionuclide studies cardiac magnetic resonance imaging (MRI) is routinely performed in patients suspect of having infiltrative cardiomyopathy. The T1 mapping procedure is currently being evaluated as a new technique for detection and quantification of global myocardial enhancement, as seen in cardiac amyloidosis. Sensitivities and specificities for detection of cardiac sarcoidosis and amyloidosis can be significantly improved by MRI, especially with late gadolinium enhancement (LGE) imaging. In cardiac sarcoidosis the use of LGE is outcome-related while in amyloidosis analysis of T1-mapping may be of prognostic value. If cardiac involvement in sarcoidosis or amyloidosis is suspected cardiac MRI including LGE should be performed for establishing the diagnosis. (orig.) [German] Die Sarkoidose und Amyloidose sind Multisystemerkrankungen, in deren Verlauf es zu einer kardialen Beteiligung kommen kann. Bildgebend wird als primaeres Verfahren die Echokardiographie eingesetzt. Zur weiteren Diagnostik wird neben der Biopsie und nuklearmedizinischen Verfahren v. a. die MRT herangezogen. Als neuere Technik zur Darstellung globaler diffuser Kontrastmittelanreicherungen, wie sie im Rahmen der Amyloidose vorkommen, wird z. Z. das T1-Mapping evaluiert. Durch den Einsatz der MRT, insbesondere des Late-Gadolinium-Enhancements (LGE), koennen die Sensitivitaet und Spezifitaet in der Diagnostik der kardialen Sarkoidose und Amyloidose entscheidend verbessert werden. Bei der Sarkoidose stellt das Vorhandensein eines LGE einen

Grundwassermodellbildung – Hydrostratigraphische Bewertungen mittels GCI-PetroKf, Datenbank- und Geoinformationssystemen

DEFF Research Database (Denmark)

Koch, Alexander; Fuchs, Sven; Göbel, Patricia

reimportiert und für die Verwendung in Geoinformationssystemen (i.e. ArcGIS) weiter aufbereitet. Über Interpolationsverfahren konnte innerhalb des Programmes ArcGIS ein lateraler Bezug zwischen den verschiedenen Mächtigkeiten hergestellt werden, um so auf weitere Inhomogenitäten im Aufbau des Grundwasserleiter......-Systems schließen zu können. Anschließend wurden mittels ArcGIS die Quartärbasis des Modellraums konstruiert, sowie Grundwasserisolinien- und Grundwasserdifferenzenkarten berechnet. Die Grundwasserdifferenzenkarten reproduzieren gut die Grundwasserabsenkungen im Bereich von lokalen Tagebauen. Insgesamt zeigen sich...... gute Übereinstimmungen mit früheren hydrogeologischen Untersuchungen im Projektgebiet. Die Kombination des PetroKf-Algorithmus mit der Aufbereitung in einer Datenbank, sowie der Weiterverarbeitung in ArcGIS, zeigt einen praktikablen Weg zur Entwicklung und Parametrisierung eines hydrogeologischen...

The use of a cine-technique in the MRT investigation of the temporo-mandibular joint

International Nuclear Information System (INIS)

Vogl, T.J.; Assal, J.; Eberhard, D.; Weigl, P.; Randzio, J.

1992-01-01

A new cine-technique in a prospective study using rapid gradient echo sequences was evaluated for the MRT investigation of the temporo-mandibular joint. A newly developed hydraulic apparatus was used to produce progressive opening of the jaw and MRT appearances were recorded during predetermined points of mandibular movement. The investigation included 16 normals and 34 patients. A modified gradient echo sequence was combined with an optimised surface coil or a special double coil and this provided good spatial resolution of the articular disc and of the muscular and bony structure. Amongst the abnormal findings were luxation of the disc (15 cases), tears in the disc (5 cases), late effects of internal derangements (12 cases) and condylar hypermobility (7 cases). The new cine-technique provides specific images in any chosen position of the mandible depending on the clinical disability of the patient. (orig.) [de

MRI of pulmonary perfusion; MRT der Lungenperfusion

Energy Technology Data Exchange (ETDEWEB)

Fink, C. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen (Germany). Institut fuer Klinische Radiologie; Deutsches Krebsforschungszentrum (DKFZ), Abteilung Radiologie, Heidelberg (Germany); Risse, F.; Semmler, W. [Deutsches Krebsforschungszentrum (DKFZ), Abteilung Medizinische Physik in der Radiologie, Heidelberg (Germany); Schoenberg, S.O.; Reiser, M.F. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen (Germany). Institut fuer Klinische Radiologie; Kauczor, H.-U. [Deutsches Krebsforschungszentrum (DKFZ), Abteilung Radiologie, Heidelberg (Germany)

2006-04-15

Lung perfusion is a crucial prerequisite for effective gas exchange. Quantification of pulmonary perfusion is important for diagnostic considerations and treatment planning in various diseases of the lungs. Besides disorders of pulmonary vessels such as acute pulmonary embolism and pulmonary hypertension, these also include diseases of the respiratory tract and lung tissue as well as pulmonary tumors. This contribution presents the possibilities and technical requirements of MRI for diagnostic work-up of pulmonary perfusion. (orig.) [German] Die Perfusion der Lunge ist eine entscheidende Voraussetzung fuer einen effektiven Gasaustausch. Die Bestimmung der Lungenperfusion ist bei verschiedenen Erkrankungen der Lunge fuer Diagnostik und Therapieplanung bedeutsam. Hierzu zaehlen neben Erkrankungen der Lungengefaesse wie akute Lungenembolie und pulmonale Hypertension ebenso Erkrankungen der Atemwege, des Lungengeruests und Lungentumoren. In diesem Beitrag werden die Moeglichkeiten und technischen Voraussetzungen der MRT zur Diagnostik der Lungenperfusion dargestellt. (orig.)

Evaluation of injuries of the upper cervical spine in a postmortem study with digital radiography, CT and MRI; Evaluation experimentell erzeugter Verletzungen der oberen Halswirbelsaeule mit digitaler Roentgentechnik, Computertomographie und Magnetresonanztomographie

Energy Technology Data Exchange (ETDEWEB)

Obenauer, S.; Herold, T.; Fischer, U.; Grabbe, E. [Goettingen Univ. (Germany). Abt. fuer Roentgendiagnostik; Fadjasch, G.; Saternus, K.S. [Goettingen Univ. (Germany). Abt. fuer Rechtsmedizin; Koebke, J. [Koeln Univ. (Germany). Anatomisches Inst.

1999-12-01

obere Halswirbelsaeulen-Praeparate wurden nach definiertem Rotationstrauma sowie nach Praeparation mittels digitaler Roentgentechnik (DIMA Soft P41, Fa. Feinfokus), mittels CT (CTi, High Speed, GE) in konventioneller und in Spiraltechnik (Kollimation 1 mm, Pitch 1.0) sowie mit Hilfe der MRT (Magnetom Vision Siemens) in 2D- und 3D-Technik untersucht. Ergebnisse: Die Praeparation zeigte 6 Wirbelkoerperfrakturen, 5 Densfrakturen, 1 Fraktur des vorderen Atlasbogens, 4 knoecherne Ausrisse an den okzipitalen Kondylen und 6 Laesionen der Ligg. alaria. Die digitale Praeparateradiographie dokumentierte alle Frakturen und die 4 knoechernen Ausrissfrakturen am Condylus occipitalis. In der CT konnten alle Frakturen und ligamentaeren Verletzungen erkannt werden. Die 2D MRT wies 9 Frakturen sicher und 3 fraglich nach; die 3D MRT zeigte 7 Frakturen sicher und 5 fraglich. Von den 4 Ausrissfrakturen konnten 2 mit der 2D MRT und 1 mit der 3D MRT nachgewiesen werden. Ligamentaere Verletzungen waren sicher in der 2D MRT in 2/6 Faellen und in der 3D MRT in 1 Fall zu erkennen. Diskussion: In postmortalen Studien zeigt die CT gegenueber der digitalen Radiographie und der MRT in der Detektion von Frakturen und ligamentaeren Verletzungen der oberen Halswirbelsaeule eine Ueberlegenheit, wobei diese Ergebnisse nur bedingt auf Patienten nach Hochgeschwindigkeitstrauma uebertragbar sind. (orig.)

CT and MRI of the liver: when, what, why?; CT und MRT der Leber: wann, was, warum

Energy Technology Data Exchange (ETDEWEB)

Budjan, J.; Schoenberg, S.O.; Attenberger, U.I. [Medizinische Fakultaet Mannheim der Universitaet Heidelberg, Institut fuer Klinische Radiologie und Nuklearmedizin, Universitaetsmedizin Mannheim, Mannheim (Germany)

2017-05-15

The detection and differential diagnostic clarification of liver pathologies play an important role in almost all medical disciplines. Because of its superior soft tissue contrast, the availability of liver-specific contrast agents and functional techniques, magnetic resonance imaging (MRI) is the method of choice for the diagnostics of focal and diffuse liver pathologies. In addition to its superior detection and differentiation capabilities, MRI can provide prognostic information and enable early assessment of the therapy response for malignant liver lesions using functional techniques, especially diffusion imaging. Computed tomography (CT) is the imaging method of choice for the detection of traumatic liver injury. Despite the increasing availability of functional techniques in CT, MRI remains the overall modality of choice in liver imaging. (orig.) [German] Die Detektion und die differenzialdiagnostische Abklaerung von Leberpathologien spielen in nahezu allen medizinischen Disziplinen eine bedeutende Rolle. Ihre Vorteile in Hinblick auf Weichteilkontrast, die Verfuegbarkeit leberspezifischer Kontrastmittel und funktionelle Techniken machen die MRT zum bildgebenden Verfahren der Wahl fuer die gezielte Abklaerung fokaler oder diffuser Leberpathologien. Neben hoeheren Detektionsraten und besseren Differenzierungsmoeglichkeiten stehen in der MRT funktionelle Techniken - insbesondere die Diffusionsbildgebung - zur Verfuegung, die eine Prognoseabschaetzung und die fruehe Beurteilung von Therapieansprechen bei malignen Leberlaesionen erlauben. Die CT ist bei der Detektion traumatischer Leberverletzungen Bildgebungsverfahren der Wahl; trotz der auch in der CT zunehmend verfuegbaren funktionellen Techniken bleibt die MRT in der Leberbildgebung weiterhin ueberlegen. (orig.)

MR-Guided vacuum biopsy of 206 contrast-enhancing breast lesions; MRT-gefuehrte Vakuumbiopsie bei 206 Kontrastmittel anreichernden Laesionen der Mamma

Energy Technology Data Exchange (ETDEWEB)

Perlet, C.; Schneider, P.; Sittek, H.; Reiser, M.F. [Klinikum der Universitaet Grosshadern, Muenchen (Germany). Inst. fuer Klinische Radiologie; Amaya, B.; Grosse, A.; Heywang-Koebrunner, S.H. [Martin-Luther-Universitaet, Halle (Germany). Klinik fuer Diagnostische Radiologie

2002-01-01

Purpose: To determine the accuracy and clinical use of MR-guided vacuum biopsy (VB) of enhancing breast lesions. Material and Methods: 254 lesions were referred to MR-guided vacuum-assisted breast biopsy. In 43 (16%) patients the indication was dropped because the lesions could not be identified at the time VB was scheduled. This was due to hormonal influences (n=37), to too strong compression (n=3) or to misinterpretation of the initial diagnostic MRI. In 5 cases (2%) VB was not performed due to obesity (n=2); problems of access (n=2) or a defect of the MR-unit (n=1). VB was performed on altogether 206 lesions. In 4 cases (2%) VB was unsuccessful. This was immediately realized on the post-interventional images. Thus a false negative diagnosis was avoided. Verification included excision of the cavity in cases with proven malignancy or atypical ductal hyperplasia (ADH) and (for benign lesions) retrospective correlation of VB-histology with pre- and postinterventional MRI and subsequent follow-up. Results: 51/202 successful biopsies proved malignancy. In 7 cases ADH and in 144 cases a benign lesion was diagnosed. One DCIS was underestimated as ADH. All other benign or malignant diagnoses proved to be correct. Conclusion: MR-guided VB allows reliable histological work-up of contrast-enhancing small lesions which are not visible by any other modality. (orig.) [German] Zielsetzung: Evaluation der Wertigkeit und klinischen Anwendbarkeit der MRT-gefuehrten Vakuumbiopsie (VB) bei anreichernden Mammalaesionen. Material und Methoden: Insgesamt wurden 254 Laesionen der MRT-gefuehrten VB zugewiesen. Hiervon entfiel bei 43 Patientinnen (16%) die Biopsieindikation beim Planungs-MRT, da die urspruengliche Anreicherung hormonell (n=37), durch zu starke Kompression (n=3) oder durch eine Fehlinterpretation des vorausgegangenen diagnostischen MRT (n=3) nicht mehr abgrenzbar war. Bei 5 weiteren Laesionen (2%) war die Biopsie nicht moeglich (Adipositas n=2; Zugangsprobleme n=2; MRT

Hochaufgelöste Magnetresonanz-Bildgebung der Mäuseaorta zur Bestimmung der Dynamik funktioneller Parameter durch Laufrad-Training bei ApoE-Knock-Out-Mäusen

OpenAIRE

Offenberger, Wolfgang

2009-01-01

Einführung: Atherosklerose ist eine führende Ursache von Morbidität und Mortalität weltweit. Die ApoE-Knock-Out-Maus (ApoE-/-) ist das wichtigste Tiermodell für das Studium der Atherosklerose und von Interventionen auf diese Erkrankung. Mittels hochaufgelöster Magnet-Resonanz-Bildgebung ist es möglich, eine nicht-invasive in-vivo Gefäß-Charakterisierung bei Mäusen durchzuführen. In dieser Arbeit wurden die Auswirkungen von Sport auf die Gefäßfunktion der Aorta ascendens und abdominalis bei Ap...

Preoperative mapping of speech-eloquent areas with functional magnetic resonance imaging (fMRI): comparison of different task designs; Praeoperatives Mapping der Sprachareale mittels funktioneller Magnetresonanztomographie (fMRT) bei Patienten mit Hirntumoren: Ein Paradigmenvergleich

Energy Technology Data Exchange (ETDEWEB)

Prothmann, S.; Zimmer, C. [Leipzig Univ. (Germany). Abt. fuer Neuroradiologie; Puccini, S.; Dalitz, B.; Kuehn, A.; Kahn, T. [Leipzig Univ. (Germany). Klinik und Poliklinik fuer Diagnostische Radiologie; Roedel, L. [Leipzig Univ. (Germany). Klinik und Poliklinik fuer Neurochirurgie

2005-11-15

Purpose: Functional magnetic resonance imaging (fMRI) is a well-established, non-invasive method for pre-operative mapping of speech-eloquent areas. This investigation tests three simple paradigms to evaluate speech lateralisation and visualisation of speech-eloquent areas. Materials and Methods: 14 healthy volunteers and 16 brain tumour patients were given three tasks: to enumerate months in the correct order (EM), to generate verbs fitting to a given noun (GV) and to generate words fitting to a given alphabetic character (GW). We used a blocked design with 80 measurements which consisted of 4 intervals of speech activation alternating with relaxation periods. The data were analysed on the basis of the general linear model using Brainvoyager {sup registered}. The activated clusters in the inferior frontal (Broca) and the posterior temporal (Wernicke) cortex were analysed and the laterality indices calculated. Results: In both groups the paradigms GV and GW activated the Broca's area very robustly. Visualisation of the Wernicke's area was best achieved by the paradigm GV. The paradigm EM did not reliably stimulate either the frontal or the temporal cortex. Frontal lateralisation was best determined by GW and GV, temporal lateralisation by GV. Conclusion: The paradigms GV and GW visualise two essential aspects of speech processing: semantic word processing and word production. In a clinical setting with brain tumour patients, both, GV and GW can be used to visualise frontal and temporal speech areas, and to determine speech dominance. (orig.)

Cardiodiagnostic imaging. MRT, CT, echocardiography and other methods

International Nuclear Information System (INIS)

Erbel, R.; Kreitner, K.F.; Barkhausen, J.; Thelen, M.

2007-01-01

The book presents a differentiated approach to cardiac imaging. The focus is n cardio-MR/-CT and echocardiography. These are highly complex methods involving new equipment, new protocols and indications. The techniques are new and difficult to learn for everybody concerned. MR, CT and echocardiography must always be viewed in the context of other diagnostic methods. The interdisciplinary approach of the book addresses both radiologists and cardiologists and relies on the vast experience of the authors. The book offers more than 500 large high-quality reference images reflecting the latest state of the art. It has amethodological section in which the current methods are described (X-ray, echocardiography, nuclear medicine, angiography, CT, MRT etc.) along with their advantages and shortcomings, and a clinical section in which the main indications are described in the common standardized way (anatomy, clinical picture, interpretation, differential diagnosis). (orig.)

Signal effects of various radiographic contrast media and their interaction with gadolinium DTPA during MRT

International Nuclear Information System (INIS)

Kopka, L.; Funke, M.; Fischer, U.; Vosshenrich, R.; Schroeder, M.; Grabbe, E.

1994-01-01

T 1 and T 2 weighted signals dereived from various radiological contrast media were studied during MRT spin-echo sequences. In addition, the interaction between radiological contrast media and Gadolinium-DTPA concerning T 1 signals was evaluated. Ionic (ioxitalaminic acid) and non-ionic radiological contrast media (Iopromid, Iotrolan) were used in diagnostic concentrations. Measurements were carried out with a superconductive magnet of 1.5 Tesla. Radiological contrast media produced significantly higher signals than a physiological sodium chloride solution in T 1 -weighted spin-echo sequences. Evn small amounts (15% of total volume) of radiological contrast media during T 1 -weighted spin-echo sequences led to a significant reduction (about 25%) of the signal intensity of a 2 mM Gadolinium-DTPA solution. This may lead to diagnostic problems, as was shown in a series of 25 MR arthrograms of the shoulder. It is recommended than an interval of at least 6 hours should elapse between the use of a radiological contrst medium and an MRT examination. (orig.) [de

Weanling piglet cerebellum: a surrogate for tolerance to MRT (microbeam radiation therapy) in pediatric neuro-oncology

Science.gov (United States)

Laissue, Jean A.; Blattmann, Hans; Di Michiel, Marco; Slatkin, Daniel N.; Lyubimova, Nadia; Guzman, Raphael; Zimmermann, Werner; Birrer, Stephan; Bley, Tim; Kircher, Patrick; Stettler, Regina; Fatzer, Rosmarie; Jaggy, Andre; Smilowitz, Henry; Brauer, Elke; Bravin, Alberto; Le Duc, Geraldine; Nemoz, Christian; Renier, Michel; Thomlinson, William C.; Stepanek, Jiri; Wagner, Hans-Peter

2001-12-01

The cerebellum of the weanling piglet (Yorkshire) was used as a surrogate for the radiosensitive human infant cerebellum in a Swiss-led program of experimental microbeam radiation therapy (MRT) at the ESRF. Five weanlings in a 47 day old litter of seven, and eight weanlings in a 40 day old litter of eleven were irradiated in November, 1999 and June, 2000, respectively. A 1.5 cm-wide x 1.5 xm-high array of equally space approximately equals 20-30 micrometers wide, upright microbeams spaced at 210 micrometers intervals was propagated horizontally, left to right, through the cerebella of the prone, anesthetized piglets. Skin-entrance intra-microbeam peak adsorbed doses were uniform, either 150, 300, 425, or 600 gray (Gy). Peak and inter-microbeam (valley) absorbed doses in the cerebellum were computed with the PSI version of the Monte Carlo code GEANT and benchmarked using Gafchromic and radiochromic film microdosimetry. For approximately equals 66 weeks [first litter; until euthanasia], or approximately equals 57 weeks [second litter; until July 30, 2001] after irradiation, the littermates were developmentally, behaviorally, neurologically and radiologically normal as observed and tested by experienced farmers and veterinary scientists unaware of which piglets were irradiated or sham-irradiated. Morever, MRT implemented at the ESRF with a similar array of microbeams and a uniform skin-entrance peak dose of 625 Gy, followed by immunoprophylaxis, was shown to be palliative or curative in young adult rats bearing intracerebral gliosarcomas. These observations give further credence to MRT's potential as an adjunct therapy for brain tumors in infancy, when seamless therapeutic irradiation of the brain is hazardous.

Assessment of manual restorative treatment (MRT) with amalgam in high-caries Filipino children: results after 2 years.

Science.gov (United States)

Monse-Schneider, B; Heinrich-Weltzien, R; Schug, D; Sheiham, A; Borutta, A

2003-04-01

The atraumatic restorative treatment (ART), using only hand instruments and glass-ionomer cement as adhesive material is recommended for restorative dental treatment in disadvantaged communities lacking electricity and sophisticated dental equipment. Research is required on more durable restorative materials appropriate for populations with high-caries experience. The aim of the study was to evaluate, under field conditions, the applicability and effectiveness of an encapsulated amalgam as restorative material in ART prepared cavities in permanent teeth of children with high-caries rates. As the definition of ART restricts the manual treatment to adhesive materials the approach used is called the manual restorative treatment (MRT). Two dentists and two trained healthcare workers, using hand instruments and an encapsulated amalgam that was mixed with a manually driven triturator, placed a total of 934 restorations in the permanent dentition in 466 children. Due to irregular school attendance of Filipino children only 611 restorations could be evaluated by one independent dentist. The average age at reassessment of restorations was 27 +/- 4.5 months. 93.3% of the restorations were acceptable. The failure rate of occlusal surface restorations was 5.6% compared with 13.6% of buccal surface fillings. The survival rate of large occlusal restorations was 95.1% compared with 93.7% for small restorations. The survival of MRT restorations was not influenced by the experience and professional level of the operator. Amalgam is a suitable MRT material, especially for extensive occlusal lesions in high-caries populations. Studies of longer duration are needed to confirm this finding.

Creutzfeldt-Jakob disease: the value of MRI; Creutzfeldt-Jakob-Krankheit: Stellenwert der MRT

Energy Technology Data Exchange (ETDEWEB)

Urbach, H.; Tschampa, H.J.; Keller, E.; Schild, H.H. [Radiologische Klinik, Neuroradiologie, Rheinische Friedrich-Wilhelms-Univ. Bonn (Germany); Paus, S. [Neurologische Klinik, Rheinische Friedrich-Wilhelms-Univ. Bonn (Germany)

2001-06-01

To define the role of MRI in the diagnosis of Creutzfeldt-Jakob disease (CJD). Methods: 14 patients with suspected CJD were studied within 3 years. MRI findings were correlated with WHO established diagnostic criteria (clinical findings, EEG, CSF with 14-3-3 protein assay). Results: 12 patients had CJD. One patient each suffered from Hashimoto's encephalitis and ALS dementia complex, respectively. Nine of 12 CJD patients had increased signal intensity of the striatum (n = 8), pulvinar thalami (n = 5) and/or cerebellar and cerebral cortex (n = 3), respectively. Signal intensity was most pronounced on FLAIR sequences; six patients were studied with diffusion-weighted MRI and showed impaired diffusion in these areas. Both patients without CJD did not show the abovementioned signal changes (sensitivity 75%, specificity and positive predictive value 100%, respectively). Conclusion: If patients with suspected CJD are studied with FLAIR and diffusion-weighted sequences, this disorder can reliably be proven or ruled out. Typical MRI findings narrow down the differential diagnosis and should be included in the WHO diagnostic criteria. (orig.) [German] Bestimmung des Stellenwerts der MRT in der Diagnostik der Creutzfeldt-Jakob-Krankheit (CJK). Methoden: Analyse der MRTs von 14 innerhalb von drei Jahren mit Verdacht auf CJK zugewiesenen Patienten. Korrelation der MRTs mit den entsprechend den WHO-Diagnosekriterien etablierten Untersuchungsverfahren (Klinik, EEG, Liquor mit 14-3-3 Protein-Nachweis). Ergebnisse: 12 Patienten hatten eine CJK, jeweils ein Patient hatte eine Hashimoto-Enzephalitis bzw. einen ALS-Demenz-Komplex. Bei 9 der 12 CJK-Patienten fanden sich beidseits Signalerhoehungen des Striatum (n = 8), des Pulvinar thalami (n = 5) und/oder des Kleinhirn- bzw. Grosshirnkortex (n = 3). Die Signalerhoehungen waren am deutlichsten auf FLAIR-Aufnahmen erkennbar; 6 mit diffusionsgewichteter MRT untersuchte Patienten wiesen eine eingeschraenkte Diffusion dieser Areale

Functional and neurochemical profile of place learning after L-nitro-arginine in the rat

DEFF Research Database (Denmark)

Mogensen, Jesper; Wörtwein, Gitta; Hasman, Andreas

1995-01-01

Neurobiology, nitrogenoxid (NO), place learning, rotte, L-Nitro-Arginin, funktionel genopretning......Neurobiology, nitrogenoxid (NO), place learning, rotte, L-Nitro-Arginin, funktionel genopretning...

Retention and relearning of spatial delayed alternation in rats after ablation of the prefrontal or total non-prefrontal isocortex

DEFF Research Database (Denmark)

Wörtwein, Gitta; Mogensen, Jesper; Divac, Ivan

1994-01-01

Neurobiologi, præfrontal cortex, delayed alternation, funktionel genopretning, neocortex, rotte......Neurobiologi, præfrontal cortex, delayed alternation, funktionel genopretning, neocortex, rotte...

Epiphyseal injuries of the distal tibia. Does MRI provide useful additional information?; Epiphysenfugenverletzungen der distalen Tibia. Sinnvolle Mehrinformation durch die MRT?

Energy Technology Data Exchange (ETDEWEB)

Iwinska-Zelder, J.; Schmidt, S.; Ishaque, N.; Klose, K.J.; Hoppe, M. [Marburg Univ. (Germany). Abt. fuer Strahlendiagnostik; Schmitt, J.; Gotzen, L. [Marburg Univ. (Germany). Medizinisches Zentrum fuer Operative Medizin

1999-01-01

Plain film radiography often underestimates the extent of injury in children with epiphyseal fracture. Especially Salter-Harris V fractures (crush fracture of the epiphyseal plate) are often primarily not detected. MRI of the ankle was performed in 10 children aged 9-17 (mean 14) years with suspected epiphyseal injury using 1.0-T Magnetom Expert. The fractures were classified according to the Salter-Harris-Rang-Odgen classification and compared with the results of plain radiography. In one case MRI could exclude epiphyseal injury; in four cases the MRI findings changed the therapeutic management. The visualisation of the fracture in three orthogonal planes and the possibility of detection of cartilage and ligamentous injury in MR imaging makes this method superior to conventional radiography and CT. With respect to radiation exposure MRI instead of CT should be used for the diagnosis of epiphyseal injuries in children. (orig.) [Deutsch] Die konventionelle Roentgendiagnostik unterschaetzt haeufig das Ausmass der kindlichen Extremitaetenfrakturen mit Epiphysenbeteiligung (Typ Salter-Harris). Insbesondere werden die Kompressionsfrakturen der Wachstumsfuge (Salter-Harris V) primaer haeufig nicht erkannt. Prospektiv wurden 10 Kinder im Alter von 9-17 Jahren (Durchschnittsalter = 14 J.) mit Verdacht auf eine epiphysaere Fraktur der distalen Tibia magnetresonanztomographisch (1.0-Tesla Magnetom Expert), untersucht. Die MRT-Ergebnisse wurden auf der Basis der Klassifikation nach Salter-Harris-Rang-Odgen mit den konventionellen Roentgenbildern verglichen. In einem Fall, bei einem 15jaehrigen Patienten, gelang durch die MRT der Ausschluss einer epiphysaeren Verletzung. In 7 Faellen fuehrte der MRT-Einsatz zu einer Aenderung der Klassifikation nach Salter-Harris. Hieraus resultierte bei 4 Patienten ein Therapiewechsel. Da Frakturen, die sie begleitenden Knorpellaesionen und ligamentaere Verletzungen multiplanar dargestellt werden koennen, weist die MRT deutliche Vorteile

MR-guided biopsies of undetermined liver lesions: technique and results; MRT-gezielte perkutane Biopsie bei unklaren fokalen Leberlaesionen: Technik und Ergebnisse

Energy Technology Data Exchange (ETDEWEB)

Zangos, S.; Kiefl, D.; Eichler, K.; Engelmann, K.; Heller, M.; Herzog, C.; Mack, M.G.; Jacobi, V.; Vogl, T.J. [Inst. fuer Diagnostische und Interventionelle Radiologie, Johann-Wolfgang-Goethe-Univ. Frankfurt (Germany)

2003-05-01

Purpose: To evaluate safety and precision of liver tumor biopsies performed in an open low field system using different sequence techniques. Materials and Methods: In 47 patients with liver tumors, MR-guided biopsies were performed in a low field system (0.2 Tesla, Magnetom Open, Siemens) using two different sequences. The procedure was monitored with T1-weighted FLASH sequences (TR/TE = 100/9; 70 ) in all patients and with FISP-Rotated-Keyhole-sequence (TR/TE = 18/8; 90 ) in additional 20 patients. After positioning of the needle tip in the tumors, 166 biopsy specimens were acquired with 16 G cutting needles (Somatex{sup *}). The diameter of the biopsied lesions ranged from 1 to 10 cm (mean diameter 3.2 cm). Visibility of the needles and precision of the biopsies were evaluated. Results: All interventional biopsies were performed without vascular or organ injuries. Adequate specimens for histologic interpretation were obtained in 42 cases (89.3%). The biopsy results were non-specific in 2 patients (4.2%) and the lesions missed in 3 patients (6.3%). Mean in-room time was 35 minutes and the intervention time was 8.3 minutes. T1-weighted FLASH images proved optimal for confirming needle-tip placement during the biopsies or punctures. Organs, tumors and vessels were easily identified. The FISP sequence proved to be inferior in visualizing vessels and tumors. Conclusion: MR-guided liver biopsies are safely and precisely performed using T1-weighted FLASH-sequences with sufficient visualization of the lesions and might be complementary to US- or CT-guided biopsies. (orig.) [German] Zielsetzung: Evaluierung der Sicherheit und Genauigkeit MRT-gezielter Leberbiopsien unter Verwendung verschiedener Sequenzen. Methoden: Bei 47 Patienten mit unklaren Leberlaesionen wurden in einem offenen 0,2-Tesla-MR-System (Magnetom Open, Siemens) bildgesteuerte Biopsien unter Verwendung von zwei verschiedenen Sequenzen durchgefuehrt. Die Bildgebung erfolgte bei allen Patienten mittels T

Mediastinal fibrosis with pulmonary artery obstruction; diagnosis and investigation with helical CT imaging including 3-dimensional reconstructions; Pulomonalarterienstenose bei aggresiver Mediastinalfibrose; Diagnostik und 3D-Darstellung mittels helikaler CT-Untersuchung

Energy Technology Data Exchange (ETDEWEB)

Kolbe, M. [Inst. fuer Diagnostische Radiologie, Kantonsspital Basel (Switzerland); Helwig, A. [Inst. fuer Diagnostische Radiologie, Kantonsspital Basel (Switzerland); Habicht, J.M. [Klinik fuer Herz-Torax-Chirurgie, Universitaetskliniken Basel (Switzerland); Steinbruch, W. [Inst. fuer Diagnostische Radiologie, Kantonsspital Basel (Switzerland)

1997-07-01

An aggressive mediastinal fibrosis was found in a 42-year-old female, suffering from dysphagia, stabbing pain in the chest, and an unclear weight loss. In this case, the rare combination of esophageal involvement, bronchial narrowing, and pulmonary artery obstruction could easily be demonstrated with a barium study and a helical CT examination including three-dimensional reconstructions. (orig.) [Deutsch] Wir stellen den Fall einer 42jaehrigen Patientin vor, welche zur Abklaerung einer zunehmenden Dysphagie, stechender Thoraxschmerzen und eines Gewichtsverlustes hospitalisiert wurde. Mittels klinischer und radiologischer Abklaerung konnte eine aggressive Mediastinalfibrose diagnostiziert werden. Die seltene Kombination einer Oesophaguseinengung mit Pulmonalarterienstenosen sowie einer Bronchuskompression konnte nichtinvasiv mittels Oesophagogramm und helikaler CT-Untersuchung zuverlaessig und schnell dargestellt werden. (orig.)

Early diagnosis of skeletal disorders in childhood and adolescence by MRI; Fruehdiagnose orthopaedischer Erkrankungen des Kindes- und Jugendalters mit der MRT

Energy Technology Data Exchange (ETDEWEB)

Meurer, A.; Schwitalle, M.; Engelhardt, O.; Heine, J. [Johannes Gutenberg-Univ. Mainz (Germany). Orthopaedische Klinik und Poliklinik; Kreitner, K.F. [Johannes Gutenberg-Univ. Mainz (Germany). Inst. fuer Klinische Strahlenkunde

1998-09-18

The early diagnosis of such disorders is of major importance because, in most cases, severe consequences can only be averted by early treatment. The value of magnetic resonance imaging (MRI) in many orthopaedic and traumatological conditions is generally accepted. The value of MRI in this particular field is illustrated by typical case reports on common clinical problems [Deutsch] Der Fruehdiagnose von Erkrankungen des Kindes- und Jugendalters kommt grosse Bedeutung zu, da oftmals nur durch eine daraus resultierende Fruehbehandlung schwerwiegende Folgen vermieden werden koennen. Die Kernspintomographie (Magnetresonanztomographie=MRT) ist in zahlreichen orthopaedischen-traumatologischen Fragestellungen bereits etabliert. An ausgewaehlten Fallbeispielen haeufiger klinischer Problemstellungen soll in der vorliegenden Arbeit der Stellenwert der MRT dargestellt werden. (orig.)

Magnetic resonance imaging of pulmonary perfusion. Technical requirements and diagnostic impact; MRT der Lungenperfusion. Technische Voraussetzungen und diagnostischer Stellenwert

Energy Technology Data Exchange (ETDEWEB)

Attenberger, U.I.; Buesing, K.; Schoenberg, S.O.; Fink, C. [Klinikum Mannheim der Universitaet Heidelberg, Institut fuer Klinische Radiologie und Nuklearmedizin, Universitaetsmedizin Mannheim, Mannheim (Germany); Ingrisch, M.; Reiser, M. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Klinische Radiologie, Campus Grosshadern, Muenchen (Germany)

2009-08-15

With technical improvements in gradient hardware and the implementation of innovative k-space sampling techniques, such as parallel imaging, the feasibility of pulmonary perfusion MRI could be demonstrated in several studies. Dynamic contrast-enhanced 3D gradient echo sequences as used for time-resolved MR angiography have been established as the preferred pulse sequences for lung perfusion MRI. With these techniques perfusion of the entire lung can be visualized with a sufficiently high temporal and spatial resolution. In several trials in patients with acute pulmonary embolism, pulmonary hypertension and airway diseases, the clinical benefit and good correlation with perfusion scintigraphy have been demonstrated. The following review article describes the technical prerequisites, current post-processing techniques and the clinical indications for MR pulmonary perfusion imaging using MRI. (orig.) [German] Mit der Verfuegbarkeit leistungsfaehiger Gradientensysteme und schneller k-Raum-Akquisitionstechniken wie der parallelen Bildgebung konnten verschiedene Studien die Machbarkeit der Lungenperfusionsbildgebung in der MRT zeigen. In der Praxis haben sich dynamische kontrastverstaerkte 3D-Gradientenechosequenzen, wie sie fuer zeitaufgeloeste MR-Angiographien verwendet werden, fuer die Bildgebung der Lungenperfusion etabliert. Hiermit ist es moeglich, die Perfusion der gesamten Lunge mit ausreichend hoher zeitlicher und raeumlicher Aufloesung zu visualisieren. In mehren klinischen Studien konnte bei Patienten mit Lungenembolie, pulmonaler Hypertonie sowie Erkrankungen der Atemwege und des Lungenparenchyms der klinische Nutzen der Lungenperfusions-MRT und die gute Uebereinstimmung mit der Lungenperfusionsszintigraphie nachgewiesen werden. Der folgende Uebersichtsartikel beschreibt die technische Durchfuehrung, Bildnachverarbeitung und die klinischen Anwendungsgebiete der MRT zur Untersuchung der Lungenperfusion. (orig.)

Aneurysmatic dissection of an aberrant right subclavian artery; Disseziierendes Aneurysma einer aberranten Arteria subclavia dextra: Diagnose mittels Ultrafast-CT

Energy Technology Data Exchange (ETDEWEB)

Reittner, P. [Universitaetsklinik fuer Radiologie, Graz (Austria). Abt. fuer Allgemeine Radiologie; Stacher, R. [Universitaetsklinik fuer Radiologie, Graz (Austria). Abt. fuer Allgemeine Radiologie

1996-01-01

Diagnosis with Ultrafast-CT: An aneurysm of an aberrant right subclavian artery is a very rare cause for dysphagia. We describe such a case in a 67-year-old patient, diagnosed with Ultrafast-CT and discuss it together in concert with the embryology and the radiological findings. (orig.) [Deutsch] Eine aberrierende Arteria subclavia dextra ist eine seltene Ursache fuer Dysphagie. Anhand eines 67jaehrigen Patienten werden Embryologie und radiologische Charakteristika, diagnostiziert mittels Ultrafast-CT, diskutiert. (orig.)

Optimized detection and characterization of liver metastases. The role of current MRI contrast agents; Optimierte Detektion und Charakterisierung von Lebermetastasen. Leistungsvermoegen aktueller MRT-Kontrastmittel

Energy Technology Data Exchange (ETDEWEB)

Weinrich, J.M.; Well, L.; Bannas, P. [Universitaetsklinikum Hamburg-Eppendorf, Zentrum fuer Radiologie und Endoskopie, Klinik und Poliklinik fuer diagnostische und interventionelle Radiologie und Nuklearmedizin, Hamburg (Germany)

2017-05-15

Metastases are the most common malignant lesions of the liver. The presence of liver metastases is an important prognostic factor and is decisive for the further management, especially in patients with colorectal cancer. Detection and characterization of liver metastases as well as differentiation from benign lesions are of high importance and a daily challenge in clinical radiology. Contrast-enhanced magnetic resonance imaging (MRI) has the highest sensitivity in detecting liver metastases. The sensitivity of MRI has been further increased due to the development of liver-specific contrast agents. This article describes the role of extracellular and hepatobiliary contrast agents for the detection and characterization of liver metastases. Moreover, the current knowledge on safety, sequence optimization, transient severe dyspnea and the combination of hepatobiliary with intravascular contrast agents for liver imaging is discussed. (orig.) [German] Metastasen sind die haeufigsten malignen Leberlaesionen. Das Vorhandensein von Lebermetastasen ist entscheidend fuer die Prognose und weitere Therapieplanung von Tumorpatienten, insbesondere von Patienten mit kolorektalen Karzinomen. Die Detektion von Lebermetastasen sowie deren Unterscheidung von anderen Leberlaesionen sind daher von hoechster Bedeutung und stellen eine alltaegliche Herausforderung fuer den Radiologen dar. Die Bildgebung mit der hoechsten Sensitivitaet fuer die Detektion von Lebermetastasen stellt die dynamische kontrastmittelgestuetzte Magnetresonanztomographie (MRT) dar. Die bereits hohe Sensitivitaet der MRT wird durch den Einsatz leberspezifischer Kontrastmittel noch weiter gesteigert. Dieser Artikel beleuchtet die Rolle der aktuellen unspezifischen und leberspezifischen MRT-Kontrastmittel fuer die Detektion und Charakterisierung von Lebermetastasen. Weiterhin werden Erkenntnisse zur Sicherheit, Sequenzoptimierung, zu transienten Atemartefakten und zur Kombination von MRT-Kontrastmitteln fuer die

MR imaging in congenital complicated anterior body wall defects; MRT von komplizierten angeborenen Bauchwanddefekten

Energy Technology Data Exchange (ETDEWEB)

Hoermann, M.; Scharitzer, M. [Universitaetsklinik fuer Radiodiagnostik, AKH-Wien (Austria); Pumberger, W. [Universitaetsklinik fuer Kinderchirurgie, AKH-Wien (Austria); Patzak, B. [Pathologisch-anatomisches Museum im Narrenturm, AKH-Wien (Austria)

2003-04-01

Introduction: Aim of this study was to estimate the value of postmortem MR imaging in evaluation of specimen with congenital anterior body wall defects of the museum of pathologic-anatomy. Material and Methods: We examined 19 specimen with a 1.5 Tesla unit by using T{sub 1}- and T{sub 2}-weighted sagittal and coronal sequences. In some specimen additional axial T{sub 2}-weighted images were obtained. We evaluated the site of the bowel, the liver, the heart and presence of associated disorders. Results: The bowels were completely intraabdominal, in two specimen, completely extraabdominal in 12 specimen and in 5 specimen intra- and extraabdominal. The liver was in two specimen completely extraabdominal/in 12 completely intracorporal, and in 5 specimen intra- and extraabdominal. In 5 cases the heart was located extraanatomically. In 12 specimen we found disorders of the spine and the extremities. Congenital disorders of the kidneys were found in 6 specimen. Conclusion: MR imaging is of great value in the assessment of congenital anterior body wall defects. In the light of ultrafast sequences the role of fetal MR imaging in the evaluation of congenital body wall defects may be mandatory in the future. (orig.) [German] Einleitung: Wir nutzten die Sammlung des pathologisch-anatomischen Museums in Wien, um die Wertigkeit der MRT zur Beschreibung von angeborenen vorderen Bauchwanddefekten und deren assoziierten Erkrankungen zu bestimmen. Material und Methode: Wir untersuchten 19 Exponate mit einem 1,5-Tesla-Geraet unter Verwendung von sagittalen und koronalen T{sub 1}- und T{sub 2}-gewichteten Sequenzen. Ausgewertet wurden die Lage des Darmes, der Leber, des Herzens und assoziierte Missbildungen. Ergebnisse: Der Darm lag in zwei Faellen intraabdominal, zur Gaenze extraabdominal in 12 Faellen, intra- und extraabdominal in 5 Faellen. Die Leber war in zwei Exponaten zur Gaenze extraabdominal, in 5 intra- und extraabdominal und in 12 Exponaten intraabdominal. Assoziiert waren

Intraoperative use of an open midfield MR scanner in the surgical treatment of cerebral gliomas; Intraoperative Nutzung eines offenen Mittelfeld-MRT waehrend der chirurgischen Therapie zerebraler Gliome

Energy Technology Data Exchange (ETDEWEB)

Schneider, J.P.; Schulz, T.; Dietrich, J.; Kahn, T. [Klinik und Poliklinik fuer Diagnostische Radiologie, Univ. Leipzig (Germany); Trantakis, C. [Klinik und Poliklinik fuer Neurochirurgie, Univ. Leipzig (Germany)

2003-07-01

The aim of the present study was to evaluate the effectiveness of intraoperative MRI guidance in achieving more gross-total resection in case of primary brain tumors. We studied 12 patients with low-grade glioma and 19 patients with high-grade glioma who underwent surgery within a vertically open 0.5T MR system. After initial imaging, the resection was stopped at the point in which the neurosurgeon considered the resection complete by viewing the operation field. At this time, intraoperative MRI was repeated (''first control'') to identify any residual tumor. Areas of tumor-suspected tissue were localized and resected, with the exception of tissue adjacent to eloquent areas. Final imaging was carried out before closing the craniotomy. Comparison of ''first control'' and final imaging revealed a decrease of residual tumor volume from 32% to 4.3% in low-grade gliomas, and from 29% to 10% in high-grade gliomas. Intraoperative MRI allows a clear optimization of microsurgical resection of both low-grade and high-grade gliomas. (orig.) [German] Ziel der Untersuchung war es, die Effektivitaet des Einsatzes der intraoperativen MRT bei der Resektion gliogener Hirntumoren zu pruefen. 12 Patienten mit niedriggradigem Gliom und 19 Patienten mit Glioblastom wurden in einem vertikal offenen 0,5-T-MRT operiert. Nach der initialen Bildgebung erfolgte die Resektion bis zu dem Zeitpunkt, an dem der Neurochirurg kein Tumorgewebe mehr im OP-Situs abgrenzen konnte. Zu diesem Zeitpunkt erfolgte eine erneute MRT (''= erste Kontrolle'') zur Visualisierung nur MR-tomographisch darstellbaren Resttumors. Solche Areale wurden im OP-Situs lokalisiert und mit Ausnahme von Strukturen in der Naehe eloquenter Hirnareale reseziert. Vor Verschluss des Schaedels erfolgte eine abschliessende MR-Kontrolle. Durch Einsatz der intraoperativen MRT konnte eine Absenkung des relativen Resttumorvolumens von 32% auf 4,3% bei niediggradigen Gliomen und

Dental magnetic resonance tomography (dental-MRT) as a method for imaging of the maxillo-mandibular bone

International Nuclear Information System (INIS)

Gahleitner, A.; Nasel, C.; Schick, S.; Dorffner, S.; Imhof, H.; Trattnig, S.; Bernhart, T.; Mailath, G.; Watzek, G.

1998-01-01

Purpose: To establish a new method for dental imaging using magnetic resonance tomography named Dental-MRT and to demonstrate its usefulness in diagnosing dentogen pathologies of the mandible and maxilla. Methods: Seven healthy volunteers, three patients with pulpitis, two patients with dentigerous cysts, two patients after tooth transplantation, and three patients with atrophic mandibles have been evaluated. Optimized axial T 1 - and T 2 -weighted gradient echo and spin echo sequences in 2D and 3D technique have been established to perform studies of the jaws. The acquired images were reconstructed with a standard dental software package on a workstation as panorama and cross-sectional views of the mandible or maxilla. Results: The entire maxillo-mandibular bone, teeth, dental pulp, and the content of the mandibular canal were well depicted. Patients with pulpitis demonstrate bone marrow edema in the periapical region. Dentigerous cysts and their relation to the surrounding structures are clearly shown. After contrast media administration marked enhancement of the dental pulp can be demonstrated. Conclusion: Dental-MRT promises to provide a new tool for visualization and detection of dental diseases. (orig.) [de

Magnetic resonance imaging of dilated cardiomyopathy; MRT bei dilatativen Kardiomyopathien

Energy Technology Data Exchange (ETDEWEB)

D' Anastasi, M. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Greif, M. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Medizinische Klinik und Poliklinik I, Muenchen (Germany); Reiser, M.F.; Theisen, D. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Deutsches Zentrum fuer Herzkreislaufforschung (DZHK), Muenchen (Germany)

2013-01-15

Dilated cardiomyopathy (DCM) is the most common type of cardiomyopathy with a prevalence of 1 out of 2,500 in adults. Due to mild clinical symptoms in the early phase of the disease, the true prevalence is probably even much higher. Patients present with variable clinical symptoms ranging from mild systolic impairment of left ventricular function to congestive heart failure. Even sudden cardiac death may be the first clinical symptom of DCM. The severity of the disease is defined by the degree of impairment of global left ventricular function. Arrhythmias, such as ventricular or supraventricular tachycardia, atrioventricular (AV) block, ventricular extrasystole and atrial fibrillation are common cardiac manifestations of DCM. Magnetic resonance imaging (MRI) plays an important role in the exact quantification of functional impairment of both ventricles and in the evaluation of regional wall motion abnormalities. With its excellent ability for the assessment of myocardial structure, it is becoming increasingly more important for risk stratification and therapy guidance. (orig.) [German] Die dilatative Kardiomyopathie (DCM) ist die haeufigste Form der Kardiomyopathie mit einer Praevalenz von 1/2500 Erwachsenen. Aufgrund der zunaechst milden klinischen Symptomatik ist jedoch von einer relativ hohen Dunkelziffer auszugehen. Die klinische Praesentation ist variabel, die Schwere der Erkrankung wird vom Ausmass der systolischen Funktionseinschraenkung bestimmt. Herzrhythmusstoerungen, wie ventrikulaere oder supraventrikulaere Tachykardien, AV-Blockierungen, ventrikulaere Extrasystolen und Vorhofflimmern sind moegliche klinische Manifestationen. Bei manchen Patienten ist der ploetzliche Herztod die erste klinische Manifestation der Erkrankung. Die kardiale MRT spielt eine bedeutende Rolle fuer die Beurteilung des Ausmasses der ventrikulaeren Dilatation, Dysfunktion und fuer die Beurteilung regionaler Wandbewegungsstoerungen. Darueber hinaus kann sie zur Anwendung kommen

Craniocerebral trauma. Magnetic resonance imaging of diffuse axonal injury; Schaedel-Hirn-Trauma. MRT bei diffuser axonaler Verletzung

Energy Technology Data Exchange (ETDEWEB)

Mallouhi, A. [Medizinische Universitaet Wien, Allgemeines Krankenhaus, Abteilung fuer Neuro- und Muskuloskelettale Radiologie, Klinik fuer Radiologie und Nuklearmedizin, Wien (Austria)

2014-09-15

fuer Behinderung oder Tod. Es fuehrt haeufig zu einer axonalen Scherverletzung. Die daraus resultierende Pathologie wird als diffuse axonale Verletzung (''diffuse axonal injury'', DAI) bezeichnet. Die DAI-assoziierten Laesionen treten bilateral und verteilt auf und werden in der oberflaechlichen und in der tiefen weissen Substanz beobachtet. Sie finden sich sowohl in der Naehe als auch weit entfernt von der Aufprallstelle. Bei klinischem Verdacht auf eine diffuse axonale Verletzung ist die Magnetresonanztomographie (MRT) zur weiteren Abklaerung die Methode der Wahl, dies insbesondere bei Patienten mit einer unauffaelligen Computertomographie des Schaedels. Zur Abklaerung des Gehirns nach einem Schaedel-Hirn-Trauma (SHT) wird ein multimodales MR-Verfahren angewendet, das in 2 Kategorien unterteilt werden kann: strukturelle und funktionelle MR-Bildgebung. Fuer die strukturelle MRT kommen hauptsaechlich die Fluid-attenuated-inversion-recovery(FLAIR)-Gewichtung und die suszeptibilitaetsgewichtete Bildgebung (SWI) zum Einsatz. Die SWI ist ausserordentlich auf Blutabbauprodukte empfindlich, welche als kleine Signalausloeschungen an 3 typischen Lokalisationen (an der Rinden-Mark-Grenzzone, im Corpus callosum und im Hirnstamm) zur Darstellung kommen. Die funktionelle MRT umfasst eine Gruppe staendig in Entwicklung befindlicher Techniken, welche ein grosses Potenzial zur optimalen Evaluierung der weissen Substanz bei Patienten nach einem SHT haben. Diese modernen bildgebenden Verfahren ermoeglichen die Visualisierung der mit Scherverletzungen assoziierten Veraenderungen, wie die Funktionsbeeintraechtigung der Axone, die verminderte Durchblutung und abnormale metabolische Aktivitaet der betroffenen Gehirnanteile. Die multimodale MR-Abklaerung bei Patienten mit DAI fuehrt zu einer detaillierteren und differenzierteren Darstellung der zugrunde liegenden pathophysiologischen Veraenderungen der verletzten Nervenbahnen und traegt zur Verbesserung der

Detection of liver lesions with gadolinium-enhanced VIBE sequence in comparison with SPIO-enhanced MRI; Detektion von Leberlaesionen mit der Gadolinium-verstaerkten VIBE-Sequenz im Vergleich zur SPIO-verstaerkten MRT

Energy Technology Data Exchange (ETDEWEB)

Heim, P.; Steiner, P.; Dieckmann, C.; Adam, G. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie; Schoder, V. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Inst. fuer Medizinische Biometrie und Epidemiologie; Kuhlencordt, R. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Klinik und Poliklinik fuer Allgemein-, Viszeral-, und Thoraxchirurgie

2003-10-01

Purpose: Detection of malignant liver lesions with gadolinium-enhanced volumetric interpolated breath-hold examination (VIBE) in comparison with SPIO-enhanced MRT (four different SPIO-enhanced T2w sequences) and histological and imaging follow-up in non-cirrhotic livers at 1.5 T. Patients and methods: Twenty-two patients with suspected focal liver lesions prospectively underwent a gadolinium-enhanced 3D VIBE. Four T2w sequences (HASTE sequence, fast spin-echo-sequence with and without fat-saturation, FLASH 2D gradient echo-sequence) after administration of superparamagnetic iron oxide (SPIO) served as gold standard combined with histological work-up in 17 patients and histological and imaging follow-up in five patients. The image quality was evaluated and the detectability of intrahepatic lesions was rated by the alternative free-response receiver operating characteristic (AFROC) analysis. In addition, the contrast-to-noise ration was compared. Results: Altogether 49 malignant and 35 benign liver lesions were found. Concerning the image quality, VIBE turned out to be of slightly poorer image quality than the SPIO-enhanced examination with HASTE sequence (4.95 vs. 5.0). The fast spin-echo-sequence without fat-saturation demonstrated the highest contrast-to-noise ratio. All sequences showed a comparable certainty in detecting lesion (area under the curve 0.68-0.74) and identifying malignant liver lesions. Conclusions: Despite the small number of patients, VIBE seems to be a comparable, inexpensive and fast method in diagnosing malignant liver lesions. (orig.) [German] Ziel: Detektion maligner Leberlaesionen mit der Gadolinium-verstaerkten 3D-Gradientenecho-Sequenz in Atemanhaltetechnik (VIBE-Sequenz) im Vergleich mit der SPIO-verstaerkten MRT (vier verschiedene SPIO-verstaerkte T2-gew. Sequenzen) sowie histologischen und bildgebenden (Verlaufs-) Untersuchungen in nicht-zirrhotischen Lebern bei 1,5 T. Patienten und Methoden: 22 Patienten mit Verdacht auf maligne

Synthese von analogen Filtern auf einer rekonfigurierbaren Hardware-Architektur mittels eines Genetischen Algorithmus

Directory of Open Access Journals (Sweden)

S. Trendelenburg

2008-05-01

Full Text Available Rekonfigurierbare Analog-Arrays (FPAAs sind der Versuch, die Vorteile der aus der digitalen Welt bekannten FPGAs (Flexibilität, Entwurfsgeschwindigkeit auch für analoge Anwendungen verfügbar zu machen. Aufgrund der Vielfalt der analogen Schaltungstechnik ist die Abbildung von vorgegebenen Schaltungskonzepten auf eine FPAA-Architektur nicht immer einfach lösbar.

Diese Arbeit stellt einen neuen Ansatz für die Synthese von Filtern auf einer FPAA-Architektur für zeitkontinuierliche Analogfilter mittels eines Genetischen Algorithmus (GA vor. Anhand eines Matlab-Modells des FPAA, das eine gute übereinstimmung mit Simulationen des FPAA auf Transistorebene aufweist, wurde gezeigt, dass eine große Vielzahl verschiedener Filterstrukturen auf dieser Architektur dargestellt werden kann. Daraufhin wurde ein Genetischer Algorithmus entwickelt, der es erlaubt, aus einer gegebenen Filterspezifikation Konfigurationsdatensätze zu synthetisieren, die den gewünschten Filter auf die FPAA-Architektur abbilden.

Altheim geothermal plant. Power generation by means of an ORC turbogenerator; Geothermieanlagen Altheim. Stromerzeugung mittels Organic-Rankine-Cycle Turbogenerator

Energy Technology Data Exchange (ETDEWEB)

Pernecker, G [Marktgemeindeamt Altheim (Austria)

1997-12-01

The report describes the project of the Austrian market town of Altheim to generate electricity by means of an ORC turbogenerator using low-temperature thermal water. The project is to improve the technical and economic situation of the existing industrial-scale geothermal project. (orig.) [Deutsch] Der Bericht beschreibt das Vorhaben der Marktgemeinde Altheim in Oberoesterreich, Strom mittels eines Organic-Rankine-Cycle-Turbogenerators unter Verwendung niedrig temperierten Thermalwassers zu produzieren. Ziel bzw. der Zweck des Projektes ist es, die technische und wirtschaftliche Situation der bestehenden Grossthermieanlage zu verbessern. (orig.)

MR imaging of gastric wall layers in vitro: correlation to the histologic wall structure; Experimentelle Darstellung der Schichten der Magenwand mittels MRT: Korrelation mit dem histologischen Wandaufbau

Energy Technology Data Exchange (ETDEWEB)

Lubienski, A.; Grenacher, L.; Schipp, A.; Duex, M. [Radiologische Klinik, Abt. Radiodiagnostik, Ruprecht-Karls-Univ. Heidelberg (Germany); Reith, W. [Abt. fuer Neuroradiologie der Radiologischen Universitaetsklinik, Univ. Saarland (Germany); Mechtersheimer, G. [Inst. fuer Allgemeine Pathologie, Ruprecht-Karls-Univ. Heidelberg (Germany)

2002-04-01

vier Magenwandschichten auf den MR-Bildern voneinander differenziert werden. Der direkte Vergleich dieser Magenwandschichten mit den korrespondierenden histologischen Schnitten ergab von lumenseitig betrachtet folgende Korrelation: 1. Schicht: intermediaeres Signal - Mukosa, 2. Schicht: hypointenses Signal - Lamina muscularis mucosae, 3. Schicht: hyperintenses Signal - Submukosa, 4. Schicht: intermediaeres Signal - Muscularis propria. Schlussfolgerungen: Magnetresonanztomographisch sichtbare Magenwandschichten wurden dem anatomischen Wandaufbau des Magens mit Erfolg zugeordnet. Damit besteht erstmals die Moeglichkeit, die Tiefeninfiltration eines Magenkarzinoms mit Hilfe hochaufgeloester MR-Aufnahmen zu beurteilen. Diese Einschaetzung gilt ausdruecklich nicht fuer die Subserosa und Serosa, da ueber die Darstellbarkeit dieser sehr variablen Wandschichten durch die MRT noch keine Aussage zu treffen ist. (orig.)

The role of high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) in the diagnosis of preoperative and postoperative complications caused by acquired cholesteatomas; CT und MRT des erworbenen Cholesteatoms: Prae- und postoperative Bildgebung

Energy Technology Data Exchange (ETDEWEB)

Krestan, C.; Czerny, C. [Abteilung fuer Osteologie, Univ.-Klinik fuer Radiodiagnostik, Wien (Austria); Gstoettner, W. [Univ.-Klinik fuer Hals-Nasen-Ohren-Heilkunde, Frankfurt (Germany); Franz, P. [Univ.-Klinik fuer Hals-Nasen-Ohren-Heilkunde, Wien (Austria)

2003-03-01

The role of high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) in the diagnosis of preoperative and postoperative complications caused by acquired cholesteatomas will be described in this paper. The pre- and postoperative imaging of the temporal bone was performed with HRCT and MRI. HRCT and MRI were performed in the axial and coronal plane. MRI was done with T2 weighted and T1 weighted sequences both before and after the intravenous application of contrast material. All imaging findings were confirmed clinically or surgically. The preoperative cholesteatoma-caused complications depicted by HRCT included bony erosions of the ossicles, scutum, facial canal in the middle ear, tympanic walls including the tegmen tympani, and of the labyrinth. The preoperative cholesteatoma-caused complications depicted by MRI included signs indicative for labyrinthitis, and brain abscess. Postoperative HRCT depicted bony erosions caused by recurrent cholesteatoma, bony defects of the facial nerve and of the labyrinth, and a defect of the tegmen tympani with a soft tissue mass in the middle ear. Postoperative MRI delineated neuritis of the facial nerve, labyrinthitis, and a meningo-encephalocele protruding into the middle ear. HRCT and MRI are excellent imaging tools to depict either bony or soft tissue complications or both if caused by acquired cholesteatomas. According to our findings and to the literature HRCT and MRI are complementary imaging methods to depict pre- or postoperative complications of acquired cholesteatomas if these are suspected by clinical examination. (orig.) [German] In dieser Arbeit wird die Rolle der hochaufloesenden Computertomographie (HRCT) und der Magnetresonanztomographie (MRT) zur Abklaerung prae- und postoperativ bedingter Komplikationen erworbener Cholesteatome beschrieben. Die Bildgebung wurde sowohl mit der HRCT als auch mit der MRT durchgefuehrt. Die HRCT und die MRT wurden in axialer und koronaler Ebene (auch

Clinical value of MRI concerning dissection of the supraaortic vessels; Wertigkeit der MRT bei posttraumatischer Dissektion supraaortaler Gefaesse

Energy Technology Data Exchange (ETDEWEB)

Pauls, S.; Goerich, J.; Kraemer, S. [Abt. fuer Diagnostische Radiologie, Univ. Ulm (Germany); Hartwig, E. [Unfall- und Wiederherstellungschirurgie, Univ. Ulm (Germany)

2002-03-01

Purpose: Evaluation of the potential of MRI concerning dissection of the supra-aortic vessels after cervical trauma. Patients and methods: During the time period from August 1998 to February 2001, 148 patients with trauma were examined by means of MRI scan of the neck / cervical spine or skull concerning morphology of the cervical spine as well as the brain tissue. MRI sequences were weighted T{sub 1} and T{sub 2} before and after contrast medium in transverse and sagittal slices. Additional time of flight (TOF) sequences and contrast-enhanced angiography were acquired. The MRI images were examined by two experienced radiologists when tied consensus was reached. Results: 7 patients (4,7%) with a total of 9 dissections of the vertebral and/or internal carotid artery were found; diagnosis was done on TOF images, contrast enhances MR-angiography, transversal T{sub 1}- and T{sub 2}-weighted sequences as well as T{sub 1}-weighted images post-contrast medium. Therapy was changed accordingly in 4 cases and anticoagulation initiated. Conclusion: All patients with cervical injuries should be screened by MRI including MR-angiography, T{sub 1}-weighted images pre- and post-contrast agent to achieve a sure diagnosis concerning the precise size of the dissection. MRI has proven to be an excellent diagnostic tool for our patient group. (orig.) [German] Ziel: Beurteilung der Bedeutung der MRT bezueglich der Dissektionen supraaortaler Gefaesse im Rahmen cervicaler Traumata. Patienten und Methode: Im Zeitraum von August 1998 bis Februar 2001 wurden an unserer Klinik 148 Patienten mit Traumata zugewiesen, welche zur Abklaerung einer Gefuegestoerung der HWS bzw. Ausschluss einer Myelonaffektion eine MRT-Untersuchung des Halses / der HWS oder Schaedels erhielten. Es wurden jeweils T{sub 1}- und T{sub 2}-gewichtete Sequenzen in transversaler und sagittaler Schnittfuehrung vor und nach Kontrastmittelgabe angefertigt. Zusaetzlich wurden TOF-Sequenzen sowie kontrastunterstuetzte

Multiparametric MRI of the prostate. Important radiological findings for urologists; Multiparametrische MRT der Prostata. Wichtige radiologische Befunde fuer den Urologen

Energy Technology Data Exchange (ETDEWEB)

Schlemmer, Heinz-Peter [Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany)

2017-08-15

High prevalence of prostate cancer with multifocality and biological heterogeneity. Insufficient conventional urological diagnostics. Discrimination between significant and insignificant cancer needed. Digital rectal examination, prostate-specific antigen (PSA) serum level, systematic transrectal ultrasound (TRUS)-guided prostate biopsy. Multiparametric magnetic resonance imaging (mpMRI) including T2-weighted (T2w), diffusion-weighted and dynamic contrast-enhanced MRI according to the prostate imaging reporting and data system (PIRADS), MR-targeted biopsy, most frequently MR/TRUS image fusion biopsy. Prostate cancer is characterized by low signal intensity on T2w MRI, restricted water diffusion and pronounced and early uptake of contrast enhancement. Sensitivity and specificity according to the current literature are ca. 80% and 90%, respectively. In cases of suspected prostate cancer, most accurate are mpMRI according to PIRADS and in cases of positive findings, MRI-targeted biopsy, most frequently as MRI/TRUS image fusion biopsy. (orig.) [German] Hohe Praevalenz des Prostatakarzinoms mit Multifokalitaet und biologischer Heterogenitaet. Unzureichende konventionelle urologische Diagnostik. Unterscheidung klinisch signifikanter von klinisch nicht signifikanten Karzinomen erforderlich. Digitale rektale Untersuchung, Serum-PSA (prostataspezifisches Antigen), transrektale Sonographie (TRUS), systematische transrektale TRUS-Biopsie. Multiparametrische Magnetresonanztomographie (mpMRT) mit T2w- und diffusionsgewichteten sowie dynamischen kontrastmittelverstaerkten T1w-Sequenzen, dem Standard nach dem Prostate Imaging Reporting and Data System (PIRADS) entsprechend. MR-unterstuetzte Biopsie, meist MR-/TRUS-Fusionsbiopsie. Prostatakarzinome sind typischerweise T2-hypointens mit eingeschraenkter Diffusion und zeigen eine rasche Kontrastmittelanflutung. Nach der Literatur betragen Sensitivitaet und Spezifitaet der mpMRT ca. 80 bzw. 90 %. Fuer die Abklaerung bei Verdacht auf

Value of breast MRI as supplement to mammography and sonography for high risk breast cancer patients; Wertigkeit der Mamma-MRT als Ergaenzung zu Mammographie und Sonographie bei Patientinnen mit erhoehtem Mammakarzinomrisiko

Energy Technology Data Exchange (ETDEWEB)

Schlossbauer, T.; Hellerhoff, K.; Reiser, M. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Klinische Radiologie, Muenchen (Germany)

2008-04-15

The aim of this study is to give an overview on early detection of breast cancer in patients with an increased risk of breast cancer. Sensitivities and diagnostic accuracies of breast MRI, mammography and ultrasound were compared. A systematic literature search of the past 3 years was performed. Studies which compared breast imaging modalities and used image-guided biopsy results as standard of reference were included. Patients included had to have had an increased lifetime risk for breast cancer (>15%). Regarding sensitivity and diagnostic accuracy, breast MRI performed best in comparison to the other modalities within this collective of patients. Sensitivities ranged from 71-100%, 0-78%, and 13-65%, for MRI, mammography, and ultrasound, respectively Breast MRI is a well established tool for screening in patients at high risk for developing breast cancer and is a valuable supplement to mammography and ultrasound within this selected cohort of patients. (orig.) [German] Ziele der Arbeit sind die inhaltliche Einfuehrung in das Thema Frueherkennung des Mammakarzinoms bei Patientinnen mit erhoehtem Risiko und eine systematische Analyse der Wertigkeit von MRT und anderen bildgebenden Verfahren in diesem Zusammenhang. Es wurde eine systematische Literaturrecherche ueber die letzten 3 Jahre durchgefuehrt. Dabei wurden Vergleichsstudien der verschiedenen bildgebenden Verfahren in der Mammadiagnostik beruecksichtigt, bei denen die bildgesteuerte Biopsie als Goldstandard angegeben wurde. Von allen bildgebenden Verfahren zeigt die Mamma-MRT bei Patientinnen mit familiaerem Risiko die hoechste Sensitivitaet und diagnostische Genauigkeit bei der Detektion des Mammakarzinoms. Fuer MRT, Mammographie und Sonographie werden Sensitivitaeten zwischen 71 und 100%, 0 und 78% sowie 13 und 65% angegeben. Die Mamma-MRT ist ein etabliertes Verfahren zum Screening von Risikopatientinnen. Uebereinstimmend wird der diagnostische Nutzen der Mamma-MRT als ergaenzendes Verfahren zu Mammographie

Diagnosis of cerebral metastases by means of standard doses of Gadobutrol versus a high-dose protocol. Intraindividual evaluation of a phase-II high-dose study; Zerebrale Metastasendiagnostik mittels Standarddosis Gadobutrol vs. einem Hochdosisprotokoll. Intraindividuelle Evaluierung einer Phase-II-Hochdosisstudie

Energy Technology Data Exchange (ETDEWEB)

Vogl, T.J. [Strahlen- und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Friebe, C.E. [Strahlen- und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Balzer, T. [Schering AG, Berlin (Germany); Mack, M.G. [Strahlen- und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Steiner, S. [Strahlen- und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Schedel, H. [Strahlen- und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Pegios, W. [Strahlen- und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Lanksch, W. [Neurologische Klinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Banzer, D. [Behring Krankenhaus, Berlin (Germany); Felix, R. [Strahlen- und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany)

1995-08-01

In a clinical phase-II study 20 patients who had been diagnosed as having brain metastases with CT or MRT were studied prospectively with Gadobutrol, a new nonionic, low osmolality contrast agent. Each patient received an initial injection of 0.1 mmol/kg body weight and an additional dose of 0.2 mmol/kg Gadobutrol 10 min later. Spinecho images were obtained before and after the two applications of Gadobutrol. Dynamic scanning (Turbo-FLASH) was performed for 3 min after each injection of the contrast agent. Both quantitative and qualitative data were intraindividually evaluated. The primary tumor was a bronchial carcinoma in 11 cases; in 9 other cases there were different primary tumors. Forty-eight hours after the use of Gadobutrol there were no adverse signs in the clinical examination, vital signs or blood and urine chemistry. Statistical analysis (Friedman test and Wilcoxon test) of the C/N ratios between tumor and white matter, percentage enhancement, and visual assessment rating revealed statistically significant superiority of high-dose Gadobutrol injection in comparison to the standard dose. The percentage enhancement increased on average from 104% after 0.1 mmol/kg to 162% after 0.3 mmol/kg Gadobutrol. Qualitative delineation and contrast of the lesions increased significantly. The use of high-dose Gadobutrol improved the detection of 36 additional lesions in 6 patients. (orig./VHE) [Deutsch] In einer Phase-II-Studie wurden 20 Patienten mit zerebralen Metastasen eines Primaertumors ausserhalb des ZNS mit dem nichtionischen, paramagnetischen Kontrastmittel Gadobutrol magnetresonanztomographisch untersucht. T1- und T2-gewichtete Nativsequenzen und T1-gewichtete Postkontrastsequenzen wurden gemessen nach einer Dosis von 0,1 mmol/kg KG und nach einer additiven Dosis von 0,2 mmol/kg KG Gadobutrol 10 min nach Erstinjektion. Mittels Turbo-FLASH-Sequenzen wurde die Dynamik der Konstrastmittelanreicherung gemessen. Die klinischen und laborchemischen Untersuchungen

Magnetic resonance imaging in the evaluation of pneumonia; Nachweis von pneumonischen Infiltraten mit der MRT

Energy Technology Data Exchange (ETDEWEB)

Eibel, R.; Herzog, P.; Dietrich, O.; Reiser, M.; Schoenberg, S.O. [Ludwig-Maximilians-Universitaet Muenchen (Germany). Institut fuer Klinische Radiologie; Rieger, C.; Ostermann, H. [Ludwig-Maximilians-Universitaet Muenchen (Germany). Abteilung fuer Haematologie/Onkologie, Klinikum Grosshadern

2006-04-15

Magnetic resonance imaging (MRI) of the lung is challenging because of substantial drawbacks. However, lung pathologies that are associated with increased attenuation values in CT enhance visualization in MRI: proton density is increased and tissue-air interfaces, resulting in susceptibility artifacts, are reduced in pneumonia, pneumonitis, edema, and carcinoma. On the other hand, many lung diseases result in shortness of breath, so that patients cannot hold their breath for long periods. Therefore, fast imaging techniques are required which should also allow for high spatial resolution so that small lesions can be detected. Calcifications and air pockets within lesions are not readily recognized with MRI. Thin section CT is standard for the diagnosis of pneumonia. With parallel imaging techniques, MRI examination of the lungs can be performed with short periods of breath holding, which allow for sub-centimeter resolution in the z-axis. Especially for follow-up examinations in immunocompromised patients and, in some instances, for the staging of malignant diseases (malignant pleural mesothelioma, lung cancer, respectively), MRI is very promising and may contribute to a decrease in the radiation exposure of the patients. (orig.) [German] Die MRT des Lungenparenchyms ist wegen des extrem niedrigen Protonengehalts des Lungengewebes und den starken Grenzflaechen zwischen Luft und Parenchym prinzipiell sehr problematisch. Allerdings liegt bei pathologischen Lungengewebeveraenderungen eine andere Situation vor, da infolge von Oedem, Entzuendung bzw. Tumorwachstum der Protonengehalt erhoeht und die Grenzflaechen reduziert sind. Viele Erkrankungen der Lunge fuehren dazu, dass der Patient den Atem nicht lange anzuhalten vermag. Daher sind MRT-Pulssequenzen erforderlich, die eine Datenakquisition in wenigen Sekunden gestatten. Aus technischer Sicht werden die vom CT bekannten Submillimeterschichten vielleicht nie realisierbar sein, sodass sicher auch in Zukunft kleine

Anatomy of the skull base and the cranial nerves in slice imaging; Anatomie der Schaedelbasis und Hirnnerven in der Schnittbildgebung

Energy Technology Data Exchange (ETDEWEB)

Bink, A.; Berkefeld, J.; Zanella, F. [Klinikum der Goethe-Universitaet Frankfurt, Institut fuer Neuroradiologie, Frankfurt am Main (Germany)

2009-07-15

Computed tomography (CT) and magnetic resonance imaging (MRI) are suitable methods for examination of the skull base. Whereas CT is used to evaluate mainly bone destruction e.g. for planning surgical therapy, MRI is used to show pathologies in the soft tissue and bone invasion. High resolution and thin slice thickness are indispensible for both modalities of skull base imaging. Detailed anatomical knowledge is necessary even for correct planning of the examination procedures. This knowledge is a requirement to be able to recognize and interpret pathologies. MRI is the method of choice for examining the cranial nerves. The total path of a cranial nerve can be visualized by choosing different sequences taking into account the tissue surrounding this cranial nerve. This article summarizes examination methods of the skull base in CT and MRI, gives a detailed description of the anatomy and illustrates it with image examples. (orig.) [German] Zur Untersuchung der Schaedelbasis sind sowohl die Computertomographie (CT) als auch Magnetresonanztomographie (MRT) geeignet. Waehrend mittels CT vorzugsweise die exakte knoecherne Ausbreitung von Pathologien z. B. zur operativen Therapieplanung erfasst werden, dient die MRT sowohl der Darstellung von Pathologien bzgl. ihrer Ausbreitung im Weichteilgewebe als auch dem Nachweis knoecherner Infiltration. Bei der Untersuchung der Schaedelbasis wird eine hochaufloesende Darstellung mit geringer Schichtdicke fuer beide Modalitaeten angestrebt. Die genaue Kenntnis der Anatomie ist bereits bei der Untersuchungsplanung notwendig. Sie ist zudem Voraussetzung fuer das Erkennen und die korrekte Interpretation von Pathologien. Die MRT ist die bildgebende Methode der Wahl zur Abklaerung von Pathologien der Hirnnerven. Dabei ist es durch gezielte Sequenzauswahl, die sich nach den die Hirnnerven umgebenen Strukturen richtet, moeglich, den gesamten Verlauf der Hirnnerven zu beurteilen. Dieser Artikel beschreibt die Untersuchung der Schaedelbasis

Haemophilic arthropathy of the knee. Gd-DTPA enhanced MRT. Clinical and radiological correlation

International Nuclear Information System (INIS)

Naegele, M.; Kunze, V.; Hamann, M.; Eickhoff, H.; Koch, W.; Oldenburg, J.; Reiser, M.

1994-01-01

17 patients with hemophilic arthropathy of the knee joint were studied with static and dynamic MRT before and after i.v. bolus injection of Gadolinium-DTPA (0,1 mmol/kg body weight). After contrast enhancement, synovial proliferations exhibited an increase of signal intensity (SI) of FFE and SE images of 47.7% and 37.4% respectively, whereas muscle and fatty tissue, tendons, bone marrow and joint effusion revealed only minor increase in SI. The gradient of signal intensity (ratio SI/time) of pannus was 39,6% min. Gd-DTPA enhanced MRI studies delineate and quantify the synovial proliferations in hemophilic arthropathy. Dynamic studies in hemophilic arthropathy do not provide qualitative assessment of the inflammatory process. (orig.) [de

Quantitative Analyse und Visualisierung der Herzfunktionen

Science.gov (United States)

Sauer, Anne; Schwarz, Tobias; Engel, Nicole; Seitel, Mathias; Kenngott, Hannes; Mohrhardt, Carsten; Loßnitzer, Dirk; Giannitsis, Evangelos; Katus, Hugo A.; Meinzer, Hans-Peter

Die computergestützte bildbasierte Analyse der Herzfunktionen ist mittlerweile Standard in der Kardiologie. Die verfügbaren Produkte erfordern meist ein hohes Maß an Benutzerinteraktion und somit einen erhöhten Zeitaufwand. In dieser Arbeit wird ein Ansatz vorgestellt, der dem Kardiologen eine größtenteils automatische Analyse der Herzfunktionen mittels MRT-Bilddaten ermöglicht und damit Zeitersparnis schafft. Hierbei werden alle relevanten herzphysiologsichen Parameter berechnet und mithilfe von Diagrammen und Graphen visualisiert. Diese Berechnungen werden evaluiert, indem die ermittelten Werte mit manuell vermessenen verglichen werden. Der hierbei berechnete mittlere Fehler liegt mit 2,85 mm für die Wanddicke und 1,61 mm für die Wanddickenzunahme immer noch im Bereich einer Pixelgrösse der verwendeten Bilder.

Accuracy of renal volume assessment in children by three-dimensional sonography; Nierenvolumetrie im Kindesalter: Genauigkeit der dreidimensionalen Sonographie im Vergleich zur konventionellen Sonographie und CT/MRT

Energy Technology Data Exchange (ETDEWEB)

Fritz, G.A.; Riccabona, M.; Bohdal, G. [Klinik fuer Radiologie, Universitaetsklinikum Graz (Austria); Quehenberger, F. [Inst. fuer medizinische Informatik, Statistik und Dokumentation, Universitaetsklinikum Graz (Austria)

2003-04-01

Purpose: Prospective evaluation of the accuracy of three-dimensional ultrasound (3DUS) to assess the renal parenchymal volume. Materials and Methods: CT, MRI, 2DUS and 3DUS were used to measure the renal volume in 40 patients (range: neonate to 17 years; mean age: 8.95 years). The 3DUS was determined with a Voluson 730 (Kretztechnik, GE) or an external 3D-system (EchoTech, GE) using electromagnetic positioning sensors attached to conventional 2DUS-equipment. The 2DUS volume was calculated with the ellipsoid equation and the 3DUS volume computed with the system integrated software. For CT and MRI, planimetric analysis was used to determine the renal parenchymal volume, whereby the dilated collecting system of a hydronephrosis was subtracted to obtain the real renal parenchymal volume. The results of 2DUS and 3DUS were compared to the results of CT and MRI, and inter- and intraobserver variabilities were calculated. Results: In 74 of 77 kidneys, the 3DUS study was of diagnostic quality. The accuracy of the 3DUS volumes compared well to the CT and MRI volumes with a mean difference of -1.8 {+-} 4.6% versus a mean difference of -2.4 {+-} 15.4% for 2DUS. In normal kidneys, the accuracy was -2.6 {+-} 4.4% for 3DUS and -3.8 {+-} 14.7% for 2DUS. In hydronephrosis, the accuracy was +4.0 {+-} 5.9% and +9.6 {+-} 21.3%, respectively, indicating that 3DUS is more accurate than 2DUS, particularly in kidneys with a dilated collecting system. Inter- and intraobserver variabilities were {+-} 7.3% and {+-} 5.3%. Conclusion: For assessing the renal parenchymal volume in children, 3DUS is feasible and comparable to CT and MRI. (orig.) [German] Studienziel: Prospektive Evaluation der Genauigkeit des drei-dimensionalen Ultraschalls (3DUS) bei der Volumetrie der kindlichen Niere im Vergleich zur CT/MRT. Methode: Bei 40 Patienten (Alter: 0 - 17 Jahre) mit einer klinisch indizierten CT/MRT des Abdomens oder des Harntrakts wurde zusaetzlich ein 2D- und 3DUS inklusive Volumetrie des

Einfluss der Lage des aktiven Kontaktes innerhalb des Nucleus subthalamicus auf den Effekt der tiefen Hirnstimulation bei Parkinson Patienten- Eine MRT-basierte Untersuchung

OpenAIRE

Wodarg, Fritz

2013-01-01

Anhand Prä- und postoperativer MRT-Bilder wird die Lage der Elektroden zur Hochfrequenzstimulation innerhalb des N. subthalamicus bestimmt und mit dem klinischen Ergebnis der Stimulation bei 30 Parkinson Patienten korreliert. Eine Stimulation in lateralen Anteilen des STN bringt signifikant bessere klinische Ergebnisse.

MRI of the fingers in patients with systemic scleroderma. Early results of contrast-enhanced examinations on a dedicated MRI system; MRT der Finger bei systemischer Sklerodermie. Erste Ergebnisse mit kontrastverstaerkten Untersuchungen an einem dedizierten MRT-System

Energy Technology Data Exchange (ETDEWEB)

Bonel, H.; Seemann, M.; Reiser, M. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern, Univ. Muenchen (Germany); Messer, G.; Walchner, M.; Roecken, M. [Dermatologische Klinik und Poliklinik, Univ. Muenchen (Germany)

1997-10-01

Purpose. To estimate disease activity in patients with systemic sclerosis using contrast-enhanced MRI of the skin. Material and Methods. In a pre-study, sequences of a low-field (0.2 T) scanner (Artoscan, Esaote, Genova, Italy) were optimized for detection of intravenous contrast (0.1 mmol/l Gd-DTPA) in six patients with the autoimmune disease systemic scleroderma. Based on the results of the pre-study, 17 patients with scleroderma (7 sclerotic/10 active inflammatory disease) were scanned using gradient-spoiled 3D GRE sequences (FA 90 , TR 100 ms, TE 18 ms), which had been established as most sensitive for intravenous contrast. Contrast enhancement of the skin was determined quantitatively by contrast-to-noise ratios (CNR), comparing post- to pre-contrast and dynamic scans (for 6 min, 1 acquisition/min). Patients in the chronic state with sclerodactylia and active inflammation of the hands were considered separately and compared to a control group (n=10) matched according to age. Results. CNR increase after intravenous contrast was significantly higher in patients with active disease (86{+-}16% increase) than sclerosing disease (29{+-}3%, p<0.05) and the control group (4{+-}2%, p<0.05). The dynamic examination showed a significantly slower decrease after the peak rise in the first minute in patients with active disease (CNR 15.4{+-}0.7 to 14.2{+-}1.4) than in those with chronic disease (14.1{+-}0.5 to 11.3{+-}0.9, p<0.05). (orig.) [Deutsch] Zielsetzung der Arbeit war die Quantifizierung der Entzuendungsreaktion der Haut bei an systemischer Sklerodermie erkrankten Patienten mittels kontrastverstaerkter MRT. Material und Methoden. In einer Vorstudie mit 6 Patienten wurden die Sequenzen eines dedizierten Niederfeldmagnetresonanztomographen (Artoscan, Esaote, Genua, Italien) fuer den Kontrastmittelnachweis (0,1 mmol/l Gd-DTPA i.v.) optimiert. Basierend auf dieser Sequenzoptimierung wurden 17 Patienten mit systemischer Sklerodermie (7 Patienten mit sklerosierender, 10

Magnetic resonance imaging (MRI) of liver and brain in haematologic-organic patients with fever of unknown origin; Magnetresonanztomographie (MRT) der Leber und des Gehirns bei haematologisch-onkologischen Patienten mit Fieber unbekannter Ursache

Energy Technology Data Exchange (ETDEWEB)

Heussel, C.P.; Kauczor, H.U.; Poguntke, M.; Schadmand-Fischer, S.; Mildenberger, P.; Thelen, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Heussel, G. [Mainz Univ. (Germany). 3. Medizinische Klinik und Poliklinik

1998-08-01

To examine the advantage of liver and brain MRI in clinically anomalous haematological patients with fever of unknown origin. Material and Methods: Twenty liver MRI (T{sub 2}-TSE, T{sub 2}-HASTE, T{sub 1}-FLASH{+-}Gd dynamic) and 16 brain MRI (T{sub 2}-TSE, FLAIR, T{sub 1}-TSE{+-}Gd) were performed searching for a focus of fever with a suspected organ system. Comparison with clinical follow-up. Results: suspected organ system. Comparison with clinical follow-up. Results: A focus was detected in 11/20 liver MRI. Candidiasis (n=3), mycobacteriosis (n=2), relapse of haematological disease (n=3), graft versus host disease (n=1), non-clarified (n=2). The remaining 9 cases with normal MRI were not suspicious of infectious hepatic disease during follo-wup. In brain MRI, 3/16 showed a focus (toxoplasmosis, aspergillosis, mastoiditis). Clinical indication for an infectious involvement of the brain was found in 4/16 cases 2--5 months after initially normal brain MRI. No suspicion of an infectious involvement of brain was present in the remaining 9/16 cases. Conclusion: In case of fever of unknown origin and suspicion of liver involvement, MRI of the liver should be performed due to data given in literature and its sensitivity of 100%. Because of the delayed detectability of cerebral manifestations, in cases of persisting suspicion even a previously normal MRI of the brain should be repeated. (orig.) [Deutsch] Untersuchung des Nutzens der MRT der Leber und des Gehirns bei klinisch auffaelligen haematologischen Patienten mit Fieber unbekannter Ursache. Material und Methoden: Es wurden 20 MRT der Leber (T{sub 2}-TSE, T{sub 2}-HASTE, T{sub 1}-FLASH{+-}Gd dynamisch) und 16 MRT des Gehirns (T{sub 2}-TSE, FLAIR, T{sub 1}-TSE{+-}Gd) zur Fokussuche bei Infektionsverdacht und Organhinweisen durchgefuehrt. Es erfolgte der Abgleich mit dem weiteren klinischen Verlauf. Ergebnisse: 11/20 MRT-Untersuchungen der Leber zeigten einen Herdbefund: Candidiasis (n=3), Mykobakteriose (n=2

Ultrasound-guided image fusion with computed tomography and magnetic resonance imaging. Clinical utility for imaging and interventional diagnostics of hepatic lesions; Ultraschallgestuetzte Bildfusion mittels CT und MRT. Klinische Bedeutung fuer die bildgebende und interventionelle Diagnostik von Leberlaesionen

Energy Technology Data Exchange (ETDEWEB)

Clevert, D.A.; Helck, A.; Paprottka, P.M.; Trumm, C.; Reiser, M.F. [Klinikum der Ludwig-Maximilians-Universitaet, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Zengel, P. [Klinikum der Ludwig-Maximilians-Universitaet, Campus Grosshadern, Klinik fuer Hals-, Nasen- und Ohrenheilkunde, Muenchen (Germany)

2012-01-15

Abdominal ultrasound is often the first-line imaging modality for assessing focal liver lesions. Due to various new ultrasound techniques, such as image fusion, global positioning system (GPS) tracking and needle tracking guided biopsy, abdominal ultrasound now has great potential regarding detection, characterization and treatment of focal liver lesions. Furthermore, these new techniques will help to improve the clinical management of patients before and during interventional procedures. This article presents the principle and clinical impact of recently developed techniques in the field of ultrasound, e.g. image fusion, GPS tracking and needle tracking guided biopsy and discusses the results based on a feasibility study on 20 patients with focal hepatic lesions. (orig.) [German] Bei der Bildfusion von Ultraschall mit anderen schnittbildgebenden Verfahren (CT, MRT) handelt es sich um ein relativ neuartiges Verfahren, welches unter Studienbedingungen jedoch bereits erfolgreich eingesetzt wurde. In der folgenden Machbarkeitsstudie soll der Nutzen weiterfuehrender Anwendungen der sonographischen Bildfusion, dem so genannten Global-Positioning-System- (GPS-) und Needle-Tracking, untersucht werden. Dabei handelt es sich um Instrumente, die insbesondere die Diagnostik und das Staging (GPS-Tracking) bzw. die bioptische Abklaerung (Needle-Tracking) von Patienten mit fokalen Leberlaesionen erleichtern. In diesem Artikel werden das Prinzip und die Anwendungsmoeglichkeiten dieser neuen Techniken anhand konkreter Beispiele in einem Kollektiv von 20 Patienten mit fokalen Leberlaesionen vorgestellt und erlaeutert. (orig.)

Errors during MRT measurements of the left ventricular volume using a multi-slice technique

International Nuclear Information System (INIS)

Pitton, M.B.; Just, M.; Grebe, P.; Kreitner, K.F.; Erbel, R.; Thelen, M.

1992-01-01

A multi-slice technique for MRT measurements of the left ventricular volume is much faster than the use of single-slice methods and is therefore better tolerated, leaving time for additional measurements. The end-diastolic left ventricular volume can be reliably measured by this method (123.3±13.5 ml vs. 124.1±ml). The end-systolic volume is consistently overestimated by 23.7±18,3% compared with the reference value obtained by single slice measurements (47.9±8.9 ml vs 39.1±7.9 ml). Correspondingly, stroke volume and ejection fraction is underestimated on average by 10.6±9.7% and 10.6±7.6% respectively). (orig.) [de

Rekonstruktion mit Netz beim komplexen Prolaps der Frau: Was hilft es der Patientin wirklich?

Directory of Open Access Journals (Sweden)

Hierl J

2010-01-01

Full Text Available Einleitung: Der komplexe Genitaldeszensus der Frau geht oftmals mit einer deutlichen Einschränkung der Lebensqualität (LQ einher. Dennoch ist der Endpunkt der meisten klinischen Analysen rein anatomischer und funktioneller Natur. In der vorliegenden Untersuchung wurden die Einflüsse der operativen Rekonstruktion mit einem Netz prospektiv auf die LQ evaluiert. Patienten und Methoden: Bei insgesamt 111 Patientinnen mit Deszensus erfolgte zwischen 08/2005 und 12/2007 eine operative Versorgung mittels vaginaler Netzeinlage (anteriorer bzw. kompletter Mesh-Repair. Die LQ wurde prospektiv prä- und postoperativ anhand standardisierter LQ-Fragebögen erfasst. Ergebnisse: Präoperativ zeigte sich bei den Patientinnen eine signifikant reduzierte LQ gegenüber einem Normalkollektiv (p 0,01. Bei 7 % der Patientinnen mit anteriorem, und bei 11 % mit komplettem Mesh-Repair lag postoperativ kein adäquates klinisches Ergebnis vor. In diesem Kollektiv zeigte sich kein signifikanter Unterschied in den LQ-Tests prä- und postoperativ. Bei gutem postoperativem Ergebnis zeigte sich in der Gruppe mit anteriorer Netzeinlage lediglich bei 45 % (p = 0,021, bei kompletter Netzeinlage nur bei 31 % (p = 0,041 eine signifikant verbesserte LQ. Bei kleiner Fallzahl und kurzem Nachbeobachtungszeitraum kann eine gültige Aussage bezüglich der LQ nach Deszensuschirurgie mit Netzeinlage jedoch noch nicht getroffen werden.

Pediatric brain tumors of neuroepithelial tissue; Hirntumoren des neuroepithelialen Gewebes im Kindesalter

Energy Technology Data Exchange (ETDEWEB)

Papanagiotou, P.; Politi, M. [Klinikum Bremen-Mitte/Bremen-Ost, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Bremen (Germany); Bergmann, M. [Klinikum Bremen-Mitte, Institut fuer Klinische Neuropathologie, Bremen (Germany); Pekrun, A. [Klinikum Bremen-Mitte, Klinik fuer Kinder- und Jugendmedizin, paed. Haematologie/Onkologie, Neonatologie, Bremen (Germany); Juergens, K.U. [Klinikum Bremen-Mitte, ZEMODI-Zentrum fuer moderne Diagnostik, MRT, Nuklearmedizin und PET-CT, Bremen (Germany)

2014-08-15

Tumors of neuroepithelial tissue represent the largest group of pediatric brain tumors by far and has therefore been divided into several discrete tumor subtypes each corresponding to a specific component of the neuropil. The neuropil contains several subtypes of glial cells, including astrocytes, oligodendrocytes, ependymal cells and modified ependymal cells that form the choroid plexus. This review discusses the imaging aspects of the most common pediatric tumors of neuroepithelial tissue. (orig.) [German] Tumoren des neuroepithelialen Gewebes stellen die mit Abstand groesste Gruppe der paediatrischen Hirntumoren dar und werden je nach deren Ursprung in diversen Subtypen unterteilt. Das Neuropil beinhaltet diverse Subtypen von Gliazellen: Astrozyten, Oligodendrozyten, ependymale Zellen und modifizierte ependymale Zellen, die den Plexus choroideus formen. In diesem Review werden die bildgebenden Aspekte mittels CT und MRT der haeufigsten Tumoren des neuroepithelialen Gewebes diskutiert. (orig.)

[Bewusstes Erinnern und bewusstes Vergessen : der juristische Umgang mit der Vergangenheit in den Ländern Mittel- und Osteuropas / hrsg. v. Angelika Nußberger, Caroline von Gall. (Jus Internationale et Europaeum ; 52). Mohr Siebeck, Tübingen 2011.

Index Scriptorium Estoniae

Luts-Sootak, Marju, 1966-

2014-01-01

Arvustus: Bewusstes Erinnern und bewusstes Vergessen : der juristische Umgang mit der Vergangenheit in den Ländern Mittel- und Osteuropas / hrsg. v. Angelika Nußberger, Caroline von Gall (Jus Internationale et Europaeum ; 52). Mohr Siebeck, Tübingen 2011. 400 S.

Fetal MRI and ultrasound of congenital CNS anomalies; Fetales MRT und Ultraschall der angeborenen ZNS-Fehlbildungen

Energy Technology Data Exchange (ETDEWEB)

Pogledic, I.; Reith, W. [Universitaetsklinikum des Saarlandes, Homburg/Saar, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany); Meyberg-Solomayer, G. [Universitaetsklinikum des Saarlandes, Homburg/Saar, Klinik fuer Frauenheilkunde, Geburtsheilkunde und Reproduktionsmedizin, Homburg/Saar (Germany)

2013-02-15

In the last decade the newest technologies, fetal magnetic resonance imaging (MRI) and 3D ultrasound, have given an insight into the minute structures of the fetal brain. However, without knowledge of the basic developmental processes the imaging is futile. Knowledge of fetal neuroanatomy corresponding to the gestational week is necessary in order to recognize pathological structures. Furthermore, a modern neuroradiologist should be acquainted with the three steps in the formation of the cerebral cortex: proliferation, migration and differentiation of neurons in order to be in a position to suspect that there is a pathology and start recognizing and discovering the abnormalities. The fetal MRI has become an important complementary method to ultrasound especially in cortical malformations when confirmation of the prenatal diagnosis is needed and additional pathologies need to be diagnosed. In this manner these two methods help in parental counseling and treatment planning. (orig.) [German] Dank neuer Technologien (z. B. fetale MRT, 3-D-Sonographie) ist es moeglich, kleinste Hirnstrukturen darzustellen. Ohne Kenntnisse der grundlegenden Entwicklungsprozesse des Gehirns waere die Bildgebung jedoch sinnlos. Um pathologische Veraenderungen zu erkennen, ist es notwendig, den Stand der fetalen Neuroanatomie in der entsprechenden Schwangerschaftswoche zu kennen. Heutzutage sollte sich ein Neuroradiologe mit den 3 Schritten der kortikalen Entwicklung - Proliferation, Migration und Differenzierung der Neuronen - vertraut machen. Nur dann wird er in der Lage sein, pathologische Veraenderungen in Betracht zu ziehen, bzw. diese zu erkennen. Die fetale MRT ist besonders wichtig, ergaenzend zur zerebralen Sonographie, zur Diagnosebestaetigung bei kortikalen Veraenderungen und Nachweis weiterer Pathologien. In dieser Kombination ermoeglichen diese Methoden eine adaequate Beratung der Eltern und Planung der Behandlung. (orig.)

The value of magnetic resonance imaging (MRI) in the treatment planning of vertebral metastasis considering economic aspects. A cost benefit-analysis; Die Wertigkeit der Magnetresonanztomographie (MRT) unter oekonomischen Aspekten bei der Bestrahlungsplanung von Wirbelkoerpermetastasen. Eine Kosten-Nutzen-Analyse

Energy Technology Data Exchange (ETDEWEB)

Prott, F.J.; Schlehuber, E.; Scharding, B.J.; Rinast, E. [Strahlentherapie Wiesbaden, St.-Josefs-Hospital (Germany); Micke, O. [Klinik und Poliklinik fuer Strahlentherapie - Radioonkologie, Universitaetsklinikum Muenster (Germany)

2002-05-01

Is magnetic resonance imaging (MRI) based target volume definition for treatment planning of vertebral metastasis effective under economic considerations.From 1994 to 1999, a total of 137 patients with bone metastases affecting the vertebral column underwent MRI of the cercival, thoracic, or lumbar spine for the treatment planning of palliative radiation therapy. The following radiation treatment consisted in a irradiation of the affected vertebral region up to a total dose of 30-40 Gy.The cost calculation for radiotherapy and magnetic resonance tomography was done using the common tariff model (EBM) of the German Health Insurances.In 73% of patients (101 patients), magnetic resonance imaging resulted in marked corrections of the irradiation fields which would have resulted in the necessity of treatment for recurrence in the case of treatment planning without MRI.Consequently, the higher cost of MRI of 345.00 DEM (176,40 EUR) lead to a saving of 497.00 DEM (254,11 EUR) compared to a recurrence treatment of 10 fractions and of 1,428.00 DEM (730,12 EUR) compared to 20 fractions. The transport expenses for the second treatment could be saved as well.Even under economic considerations MRI is effective. (orig.) [German] Ist eine MRT-gestuetzte Zielvolumendefinition bei der Strahlentherapie von Knochenmetastasen ein sinnvolles Vorgehen unter oekonomischen Gesichtspunkten?1994-1999 wurde bei 137 Patienten mit einem ossaer metastasierenden Tumor und Befall der Wirbelsaeule eine Magnetresonanztomographie (MRT) zur Planung einer palliativen Radiatio durchgefuehrt. Die nachfolgende Strahlentherapie bestand aus einer Radiatio des betroffenen Wirbelkoerperabschnitts bis zu einer Gesamtherddosis von 30-40 Gy. Fuer die Berechnung der Kosten wurde der einheitliche Bewertungsmassstab der Deutschen Krankenkassen zugrunde gelegt.Aufgrund der MRT-Untersuchungen wurde bei 73% der Patienten eine Veraenderung des Bestrahlungsfeldes vorgenommen, die im Falle einer nicht MRT

Simulation of the beam guiding of the SAPHIR experiment by means of a differential-equation model; Simulation der Strahlfuehrung des SAPHIR-Experiments mittels eines Differentialgleichungsmodells

Energy Technology Data Exchange (ETDEWEB)

Greve, T.

1991-08-01

This paper shows the numerical simulation of a beam line by means of a model of differential equations simulating the beam line from the Bonn Electron Stretcher Accelerator ELSA to the SAPHIR spectrometer. Furthermore a method for calculating the initial values based on measurements of beam profiles is being discussed. (orig.). [Deutsch] Diese Arbeit zeigt die numerische Simulation einer Strahlfuehrung mittels eines Differentialgleichungsmodells anhand der Strahlfuehrung vom Bonner ELSA-Beschleuniger zum SAPHIR-Experiment. Weiterhin wird eine Methode zur Gewinnung der Startwerte aus Strahlprofilmessungen diskutiert. (orig.).

Monitoring of lead batteries by means of optical-fibre refractometry; Ueberwachung von Bleiakkumulatoren mittels Faseroptischer Refraktometrie

Energy Technology Data Exchange (ETDEWEB)

Gernhold, H P; Hanitsch, R

1994-12-31

Electricity storage is an integral part of photovoltaic systems. At the moment, the most economical device for this is the lead battery. Battery life is determined by the charging technique applied and by the efficiency of monitoring. The optimum charging technique is selected in dependence of battery age and charge state. The authors present a method for online charge state monitoring in which the acid concentration is measured by means of optical-fibre refractometry. (orig.) [Deutsch] Ein aeusserst wichtiger Teilbereich von Photovoltaik-Anlagen ist die Speicherung von elektrischer Energie. Diesen Zweck erfuellen Bleiakkumulatoren zur Zeit am wirtschaftlichsten. Es hat sich gezeigt, dass sowohl die angewandte Ladetechnik als auch eine gute Batterieueberwachung entscheidend fuer die Lebensdauer dieser Systemkomponente sind. Die Wahl der optimalen Ladetechnik richtet sich wiederum nach dem Alter und dem Entladegrad der Batterie. Gegenstand dieser Arbeit ist es, eine Methode vorzustellen, mit der die Saeuredichte mittels faseroptischer Refraktometrie gemessen und so der Ladezustand jeder einzelnen Batteriezelle zu jedem Zeitpunkt on-line ueberwacht werden kann. (orig.)

MRI, CT, and sonography in the preoperative evaluation of primary tumor extension in malignant pleural mesothelioma; MRT, CT und Sonographie in der praeoperativen Beurteilung der Primaertumorausdehnung beim malignen Pleuramesotheliom

Energy Technology Data Exchange (ETDEWEB)

Layer, G.; Steudel, A.; Schild, H.H. [Radiologische Universitaetsklinik Bonn (Germany); Schmitteckert, H.; Tuengerthal, S.; Schirren, J. [Thoraxklinik Heidelberg-Rohrbach (Germany); Kaick, G. van [Deutsches Krebsforschungszentrum Heidelberg (Germany). Schwerpunkt fuer Onkologische Diagnostik und Therapie

1999-04-01

Purpose: Evaluation of the diagnostic value of the imaging modalities computed tomography (CT), magnetic resonance imaging (MRI), and thoracic sonography in the preoperative staging of malignant pleural mesothelioma. Results: The accuracy rates for CT were 85%, 98%, 83%, 73%, 71%, and 83%. MRI had an accuracy of 71%, 92%, 71%, 83%, 71%, and 96%, the thoracic ultrasound examinations of 76%, 63%, 51%, 60%, 71% and 89%. Conclusions: According to these results CT remains the method of choice in the preoperative assessment of T-stage of malignant pleural mesothelioma. MRI is of nearly the same value, but is not a must. Sonography may be supplementary method for operation planning. (orig./AJ) [Deutsch] Ziel: Evaluation der diagnostischen Wertigkeit der Schnittbildverfahren MRT, CT und Sonographie in der praeoperativen Diagnostik des Pleuramesothelioms. Ergebisse: Die Treffsicherheiten betrugen fuer die genannten anatomischen Regionen im CT 85%, 98%, 83%, 73%, 71%, und 83%, im MRT 71%, 92%, 71%, 83%, 71% bzw. 96%, waehrend sich fuer die thorakale Ultraschalluntersuchung Treffsicherheiten von 76%, 63%, 51%, 60%, 71% und 89% errechneten. Schlussfolgerungen: Die CT bleibt damit das Verfahren erster Wahl in der praeoperativen Diagnostik des malignen Pleuramesothelioms. Eine unbedingte Forderung nach praeoperativer Durchfuehrung einer MRT-Untersuchung ergibt sich nach der vorliegenden Studie nicht. Die Sonographie des Thorax und oberen Abdomens liefert einen wichtigen ergaenzenden Beitrag bei der Planung der Operation des malignen Pleuramesothelioms. (orig./AJ)

Animal experimental studies on the influence of fatty infiltration of the liver on tissue relaxation times and signal changes in MRT

International Nuclear Information System (INIS)

Kreft, B.; Stark, D.; Schild, H.

1995-01-01

Using a spectrometer (n=60) in vitro and MRT imaging (n=8) in vivo, we studied the influence of fatty changes of liver cells on the relaxation times of the liver (two animal models of fatty liver disease/orotic acid, L-ethionine). Induction of fatty degeneration of the liver by means of an orotic acid diet resulted in pure deposition of fat in the liver without any histological or serological proof of inflammatory changes. Although accumulation of triglyceride in the liver reduced the T 1 relaxation time only relatively slightly (-15%), there was good correlation (r=0.88) between fat content and T 1 . There was also good correlation (r=0.92) between T 2 and histological fat content. Inflammatory changes besides fatty deposition were seen both serologically and histologically in the L-ethionine model, so that the fatty content did not correlate with T 1 . In-vivo MRT imaging showed that spin-echo sequences are inappropriate for diagnosing fatty infiltration of the liver despite the relaxation time changes produced by the fatty deposition. On the other hand, chemical-shift imaging sequences are very sensitive to identify fatty deposits, and are also independent of any additionally existing inflammatory changes. (orig.) [de

Differentiation of testicular diseases via dynamic MRT

International Nuclear Information System (INIS)

Kaiser, W.A.; Reinges, T.; Miersch, W.D.; Vogel, J.

1994-01-01

The present study aimed at resolving whether dynamic MRT can improve diagnostic relevance in diseases of the testes compared with conventional spin echo images. The testes of 20 healthy volunteers and of 16 patients of the Department of Urology of the University of Bonn were examined by means of MR tomography. Within 12 hours after MR tomography the patients were surgically explored, biopsied and if necessary orchiectomised. Results obtained with the volunteers were uniform and well reproducible, independent of external influences. On comparing the maximal enhancement curves of the examined various testicular tumors with the standard values established by examining the healthy volunteers, the curves obtained with the malignant testicular tumors were always clearly above the chosen confidence range of 3 standard deviations so that malignancy diagnosis was easy. However, the degree of maximal enhancement did not enable us to arrive at a conclusion in respect of the tumor type or the degree of malignancy. The greatest enhancement occurred with the tumor of Sertoli's cell which could thus be clearly differentiated against the other malignant testicular tumors. Due to masking of the gadolinium effect by haemosiderin deposits, haemorrhagica in the tumor tissue should be excluded by means of T 2 -weighted spin echo sequences before following up a suspicion of malignant testicular tomor. Benign intratesticular changes could be safely separated from malignant findings by means of the maximal enhancement curve lying in the normal range or below the curve of the volunteers. As with other organs, dynamic MR tomography yields definitely more and better information than conventional MR tomography also in the diagnosis of testicular tumours. However, these ''pros'' do not offset the ''cons'' of high costs of such examinations. (orig.) [de

Investigations on uncertainties in patient positioning for prostate treatment with EPID; Untersuchungen zur Positionierungsgenauigkeit bei Prostatakonformationsbestrahlungen mittels Portal-Imaging

Energy Technology Data Exchange (ETDEWEB)

Bakai, A.; Nuesslin, F. [Universitaetsklinik fuer Radioonkologie, Tuebingen (Germany). Abt. Medizinische Physik; Paulsen, F.; Plasswilm, L.; Bamberg, M. [Universitaetsklinik fuer Radioonkologie, Tuebingen (Germany). Abt. Strahlentherapie

2002-02-01

: Konformationstechniken, wie sie heutzutage routinemaessig fuer Patienten mit Prostatakarzinom angewandt werden erlauben, durch Adaption der Bestrahlungsfelder an das Planungszielvolumen (PTV) umliegendes Normalgewebe zu schonen. Um die Vorteile dieser Techniken jedoch vollstaendig nutzen zu koennen, ist die korrekte Patientenpositionierung eine wichtige Voraussetzung. In dieser Studie wurde mittels Portal-Imaging (EPID) untersucht, welche Positionierungsgenauigkeiten im Beckenbereich unter Verwendung unterschiedlicher Lagerungshilfen moeglich sind. Patienten und Methode: Fuer die Studie wurden 15 Patienten mit Prostatakarzinom ausgewaehlt, die teils mit, teils ohne Rektumballon bzw. Beckenmaske an einem Linearbeschleuniger mit Viellamellenblenden (MLC) bestrahlt wurden. Von jedem Patienten wurden mehrfach aus orthogonalen Richtungen mittels eines Portal-Imaging-Systems Aufnahmen angefertigt und anschliessend mit den Planungs-DRRs (digitally reconstructed radiographs) sowie den Simulationsaufnahmen verglichen. Ergebnisse: Trotz unterschiedlicher Lagerungshilfen konnten fuer saemtliche Patientengruppen Gesamtpositionierungsungenauigkeiten von durchschnittlich 4,0 mm (lateral), 4,5 mm (kraniokaudal) sowie 1,7 mm (dorsoventral) festgestellt werden. Mit Beckenmaske war der laterale Positionierungsfehler zwar reduziert, gleichzeitig jedoch der kraniokaudale Positionierungsfehler verstaerkt. Der Gesamtpositionierungsfehler teilte sich dabei in einen systematischen und einen statistischen Anteil auf, fuer deren verlaessliche Abschaetzung sechs bis acht EPID-Aufnahmen erforderlich waren. Schlussfolgerungen: Mittels Portal-Imaging ist es moeglich, aus einer geringen Anzahl von Verifikationsaufnahmen fuer jeden Patienten den systematischen und statistischen Positionierungsfehler zu ermitteln. Der erfolgreiche Einsatz von Lagerungshilfen zur Patientenpositionierung erfordert jedoch - insbesondere im Hinblick auf IMRT - eine weitere Optimierung. (orig.)

MR-based diagnosis and staging of female pelvic neoplasms; Diagnostik und Staging gynaekologischer Tumoren mittels MRT

Energy Technology Data Exchange (ETDEWEB)

Alt, Celine D. [Universitaetsklinik Duesseldorf (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie; Kubik-Huch, Rahel A. [Zuerich Univ. (Switzerland). Diagnostische Radiologie; Kantonsspital Baden AG (Switzerland). Dept. Medizinische Dienste

2017-06-15

Magnetic resonance imaging (MRI) is known as the cross-sectional imaging modality of choice for evaluation of the female pelvis due to an excellent soft tissue contrast and its high resolution images. It provides morphologic and functional sequences and is commonly used for evaluation of a sonographically indeterminate adnexal mass, for differentiation and characterization of pelvic organ lesions, as well as for tumor staging and therapy monitoring during/after treatment. This article gives insights into the currently valid implementation of MR-imaging, tailored to the different female pelvic organs and its special features.

Completion Report for Multi-Site Incentive MRT 2779 Implement ASC Tripod Initiative by 30SEP08

Energy Technology Data Exchange (ETDEWEB)

East, D; Cerutti, J; Noe, J; Cupps, K; Loncaric, J; Sturtevant, J

2008-09-22

This report provides documentation and evidence for the completion of the deployment of the Tripod common operating system (TripodOS, also known as and generally referred to below as TOSS). Background documents for TOSS are provided in Appendices A and B, including the initial TOSS proposal accepted by ASC HQ and Executives in July 2007 and a Governance Model defined by a Tri-Lab working group in September 2007. Appendix C contains a document that clarifies the intent and requirements for the completion criteria associated with MRT 2779. The deployment of TOSS is a Multi-Site Incentive from the ASC FY08-09 Implementation Plan due at the end of Quarter 4 in FY08.

Abdominal fat-evaluation by use of single scan computed tomography; Computertomographische Bestimmung des intraabdominellen Fettvolumens mittels Einschicht-Messung

Energy Technology Data Exchange (ETDEWEB)

Jacobi, V. [Klinikum der Johann-Wolfgang-Goethe-Univ., Frankfurt am Main (Germany). Inst. fuer Allgemeine Roentgendiagnostik; Steinkamp, M. [Klinikum der Johann-Wolfgang-Goethe-Univ., Frankfurt am Main (Germany). Inst. fuer Allgemeine Roentgendiagnostik; Kirchner, J. [Klinikum der Johann-Wolfgang-Goethe-Univ., Frankfurt am Main (Germany). Inst. fuer Allgemeine Roentgendiagnostik; Fischer, H. [Klinikum der Johann-Wolfgang-Goethe-Univ., Frankfurt am Main (Germany). 2. Medizinische Klinik; Diedrich, C.F. [Klinikum der Johann-Wolfgang-Goethe-Univ., Frankfurt am Main (Germany). 2. Medizinische Klinik; Kollath, J. [Klinikum der Johann-Wolfgang-Goethe-Univ., Frankfurt am Main (Germany). 2. Medizinische Klinik

1997-02-01

Purpose: Several studies emphasised the importance of the relationship between intraabdominal and total body adipose tissue as a risk factor for the development of metabolic or cardiovascular diseases. Therefore, the aim of the present study was to examine whether a single scan computed tomography is able to determine the whole intraabdominal fat volume with high accuracy and reproducibility. Materials and methods: Regions of interests (ROIs) were drawn manually for measuring intraabdominal fat in 51 unsuspicious abdominal CT. Results: The sexual differentiation of adipose tissue already described in a lot of studies could be confirmed in this study. Fat still predominates in females in lower half of the body (gynoid obesity). In men it predominates in the upper half (android obesity). Significant correlation concerning measuring the whole intraabdominal fat volume could be found in L1-level in women (r=0.992) and in L2-level in men (r=0.992). Measurement of a single scan enables us to assess whole intraabdominal fat volume due to a special formula. Conclusion: The determination of intraabdominal fat measured by a single scan computed tomography is a procedure associated with high accuracy and reproducibility. (orig.) [Deutsch] Ziel: Da in zahlreichen Studien hervorgehobene Bedeutung des intraabdominellen Fettgewebes gegenueber dem Gesamtkoerperfett als Risikofaktor fuer die Entwicklung metabolischer und kardiovaskulaerer Erkrankungen fordert ein Verfahren zur annaehernd exakten Bestimmung des intraabdominellen Fettgewebes. Ziel der vorliegenden Studie war zu pruefen, ob mit genuegender Genauigkeit die Verwendung einer Einschicht-Methode einen gezielten Einsatz der Computertomographie ermoeglicht und welche Lokalisation der zu waehlenden Schicht die aussagekraeftigste Messung ermoeglicht. Material und Methode: Anhand von 51 Computertomographien des Abdomens anderer Indikation (Normalbefunde) wurde das gesamte intraabdominelle Fettvolumen semiautomatisch mittels ROI

Functional MRI procedures in the diagnosis of brain tumors. Perfusion- and diffusion-weighted imaging; Funktionelle MR-Verfahren in der Diagnostik intraaxialer Hirntumoren. Perfusions- und Diffusions-Bildgebung

Energy Technology Data Exchange (ETDEWEB)

Hartmann, M. [Universitaetsklinikum Heidelberg (Germany). Neurologische Klinik, Abteilung Neuroradiologie; Heiland, S.; Sartor, K.

2002-08-01

Despite the increased diagnostic accuracy of contrast material enhanced MR imaging, specification and grading of brain tumors are still only approximate at best: neither morphology, nor relaxation times or contrast material enhancement reliably predict tumor histology or tumor grade. As histology and tumor grade strongly influence which therapy concept is chosen, a more precise diagnosis is mandatory. With diffusion- and perfusion-weighted MR imaging (DWI, PWI) it is now possible to obtain important information regarding the cellular matrix and the relative regional cerebral blood volume (rrCBV) of brain tumors, which cannot be obtained with standard MR techniques. These dynamic-functional imaging techniques are very useful in the preoperative diagnosis of gliomas, lymphomas, and metastases, as well as in the differentiation of these neoplastic lesions from abscesses, atypical ischemic infarctions, and tumor-like manifestations of demyelinating disease. Additionally, they appear suitable for determining glioma grade and regions of active tumor growth which should be the target of stereotactic biopsy and therapy. After therapy these techniques are helpful to better assess the tumor response to therapy, possible therapy failure and therapy complications such as radiation necrosis. (orig.) [German] Die radiologische Diagnostik intraaxialer Hirntumoren ist durch die Magnetresonanztomographie (MRT) erheblich verbessert worden, besonders nach Einfuehrung der paramagnetischen Kontrastmittel. Mit konventionellen MR-Verfahren ist aber noch keine verlaessliche Unterscheidung zwischen Gliomen, Metastasen, primaeren Lymphomen und tumorsimulierenden entzuendlichen Erkrankungen moeglich. In dieser Hinsicht vielversprechend sind neue, funktionell-dynamische MR-Verfahren, mit denen sich nicht-invasiv die zerebrale Wasserdiffusion und Mikrozirkulation erfassen lassen und die eine bessere Gewebecharakterisierung erlauben als die herkoemmlichen MR-Methoden. Die Perfusions-MRT erfasst

MRI for therapy planning in patients with atrial septum defects; MRT zur Therapieplanung bei Patienten mit Vorhofseptumdefekt

Energy Technology Data Exchange (ETDEWEB)

Huber, A.; Rummeny, E. [Klinikum rechts der Isar, Technische Universitaet Muenchen, Institut fuer Radiologie, Muenchen (Germany); Prompona, M.; Reiser, M.; Theisen, D. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Kozlik-Feldmann, R. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Klinik und Poliklinik fuer Kinderkardiologie, Muenchen (Germany); Muehling, O. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Medizinische Klinik I, Muenchen (Germany)

2011-01-15

The aim of this study was to determine the value of a combined magnetic resonance imaging (MRI) protocol including steady-state free precession (SSFP) imaging, phase-contrast measurements and contrast-enhanced MR angiography (CE-MRA) for presurgical or preinterventional diagnostic imaging in patients with suspected atrial septum defects. Out of 65 MRI studies of patients with suspected atrial septum defects, 56 patients were included in the study. The atrial septum defects were identified on cine images. Velocity encoded flow measurements were used to determine shunt volumes, which were compared with invasive oxymetry in 24 patients. Contrast-enhanced MRI was used to assess the thoracic vessels in order to detect vascular anomalies. The findings were compared with the intraoperative results. A total of 24 patients with high shunt volumes were treated either surgically (16 patients) or interventionally (8 patients) and 32 patients with low shunt volumes did not require surgical or interventional treatment. The vascular anomaly, which in all cases was anomalous pulmonary venous return, was confirmed by the intraoperative findings. The type and location of atrial septal defects which required treatment, were confirmed intraoperatively or during the intervention. The results of shunt quantification by MRI showed a good correlation with the results of invasive oximetry (r=0.91, p <0.0001). A combined MRI protocol including cine SSFP images, velocity-encoded flow measurements and CE-MRA is an accurate method for preoperative and preinterventional evaluation of atrial septum defects. (orig.) [German] Ziel war es, die Wertigkeit eines kombinierten MRT-Protokolls aus Funktionsuntersuchung, Flussmessung und MR-Angiographie zur praeoperativen oder -interventionellen Abklaerung bei Patienten mit Vorhofseptumdefekt zu evaluieren. Ingesamt wurden 56 Patienten mit Vorhofseptumdefekt aus einem Kollektiv von 65 Patienten mit Verdacht auf Vorhofseptumdefekt, die im MRT untersucht

Quantitatively evaluated dynamic MRT in rheumatoid arthritis of the knee joint. Follow-up after intraarticular steroid therapy. Quantitativ evaluierte dynamische Magnetresonanztomographie bei chronischer Polyarthritis des Kniegelenkes. Therapiekontrolle nach intraartikulaerer Kortisonapplikation

Energy Technology Data Exchange (ETDEWEB)

Koenig, H.; Bolze, X.; Wolf, K.J. (Klinikum Steglitz, FU Berlin, Radiologische Klinik und Poliklinik, Abt. fuer Radiologische Diagnostik und Nuklearmedizin (Germany)); Sieper, J. (Klinikum Steglitz, FU Berlin, Medizinische Klinik und Poliklinik, Abt. fuer Allgemeine Innere Medizin und Nephrologie (Germany))

1992-08-01

32 patients with chronic polyarthritis were examined by MRT. Following intra-articular application of 25 mg prednisolon, 18 patients were reexamined after two of three weeks and 7 out of 18 patients were re-examined after 8 to 16 weeks, both by MRT and clinically. After an initial double echo sequence, we carried out a dynamic series of FLASH measurements (TR 30, TE 10 ms, 70deg) following an intravenous bolus of 0.1 mmol gadolinium-DTPA. Single intensity-time curves were treated quantitatively in relation to the pannus, muscles and effusions. Two or three weeks after treatment the curve parameters showed a reduction in pannus vascularisation which remained constant for the 8 to 16 weeks of further observation. Contrast diffusion in the pannus is initially reduced but approaches the early measurements at the time of the second examination. (orig.).

MR-guided preoperative localization and percutaneous core biopsy of suspicious breast lesions - experience on the vertically open 0.5 T system; MRT-gestuetzte Markierung und Stanzbiopsie suspekter Mammalaesionen. Moeglichkeiten und Erfahrungen an einem vertikal offenen 0,5-T-System

Energy Technology Data Exchange (ETDEWEB)

Schneider, J.P.; Schulz, T.; Rueger, S.; Schmidt, F.; Kahn, T. [Universitaetsklinikum Leipzig (Germany). Klinik und Poliklinik fuer Diagnostische Radiologie; Horn, L.C. [Inst. fuer Pathologie, Universitaetsklinikum Leipzig (Germany); Leinung, S. [Chirurgische Klinik I, Universitaetsklinikum Leipzig (Germany); Briest, S. [Frauenklinik, Universitaetsklinikum Leipzig (Germany)

2002-01-01

ueberfuehren. Patienten und Methode. Initial wurde eine Methode zur Lokalisation bei sitzender Patientin unter Nutzung einer Ringspule entwickelt. Mit diesem Verfahren wurden 31 herdfoermige Laesionen lokalisiert. Weiter erfolgten in Bauchlage 46 Drahtmarkierungen und 28 Stanzbiopsien unter Verwendung einer offenen Brustspule mit integrierter Biopsieeinheit. Ergebnisse. In allen Faellen kontaktierte die Drahtfuehrungsnadel (18 G) bzw. die Koaxialschleuse (14 G) die zu punktierende Laesion (4-25, im Mittel 12 mm). Bei insgesamt 66 benignen und 39 malignen Befunden erwiesen sich die Drahtmarkierungen in 2 Faellen (Befund nach OP unveraendert) und die Stanzbiopsie in einem Fall (Revision des Ergebnisses bei Groessenprogredienz in der Kontrolle) als fehlerhaft. Schlussfolgerungen. Mit Hilfe des fuer Interventionen konzipierten vertikal offenen 0,5-T-MRT koennen sowohl praeoperative Markeirungen als auch perkutane Stanzbiopsien bei MR-suspekten Mammabefunden vorgenommen werden. Dabei kann eine Zuverlaessigkeit erreicht werden, die mit stereotaktisch oder ultraschallgefuehrten Interventionen vergleichbar ist. Kontrollen bei benignen Befunden sind unverzichtbar. (orig.)

Paradoxical effects of radioiodine therapy in functional thyroid autonomy and mild immunothyropathy; Paradoxe Effekte der Radiojodtherapie bei funktioneller Schilddruesenautonomie und milder Immunthyreopathie

Energy Technology Data Exchange (ETDEWEB)

Dunkelmann, S.; Rudolph, F.; Prillwitz, A.; Groth, P.; Schuemichen, C. [Rostock Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

1998-01-01

einer Immunthyreopathie bereits vor Radiojodtherapie. Die durch die Radiojodtherapie hervorgerufenen paradoxen Effekte betrafen eine Zunahme der Immunthyreopathie bei 14 Pat., eine Verschlechterung der Stoffwechsellage bei 13 Pat. sowie das Neuauftreten einer endokrinen Orbitopathie bei 5 Pat. Schlussfolgerung: Fuer die beobachteten paradoxen Effekte nach Radiojodtherapie wird in der ueberwiegenden Zahl der Faelle die Exazerbation einer vorbestehenden, funktionell zunaechst unbedeutenden Immunthyreopathie verantwortlich gemacht, die zur manifesten postradiogenen Immunhyperthyreose fuehrt; therapeutische Konsequenzen ergeben sich hieraus nicht. (orig.)

One decade of functional imaging in schizophrenia research. From visualisation of basic information processing steps to molecular brain imaging; Zehn Jahre funktionelle Magnetresonanztomographie in der Schizophrenieforschung. Von der Abbildung einfacher Informationsverarbeitungsprozesse zur molekulargenetisch orientierten Bildgebung

Energy Technology Data Exchange (ETDEWEB)

Tost, H. [Zentralinstitut fuer Seelische Gesundheit, NMR-Forschung in der Psychiatrie (Germany); Zentralinstitut fuer Seelische Gesundheit, NMR-Forschung in der Psychiatrie, Mannheim (Germany); Meyer-Lindenberg, A. [Genes, Neuroimaging Core Facility and Unit on Integrative Neuroimaging, Cognition and Psychosis Program, National Institute of Mental Health (United States); Ruf, M.; Demirakca, T.; Grimm, O.; Henn, F.A.; Ende, G. [Zentralinstitut fuer Seelische Gesundheit, NMR-Forschung in der Psychiatrie (Germany)

2005-02-01

Modern neuroimaging techniques such as magnetic resonance imaging (MRI) and positron emission tomography (PET) have contributed tremendously to our current understanding of psychiatric disorders in the context of functional, biochemical and microstructural alterations of the brain. Since the mid-nineties, functional MRI has provided major insights into the neurobiological correlates of signs and symptoms in schizophrenia. The current paper reviews important fMRI studies of the past decade in the domains of motor, visual, auditory, attentional and working memory function. Special emphasis is given to new methodological approaches, such as the visualisation of medication effects and the functional characterisation of risk genes. (orig.) [German] Bildgebende Verfahren wie die Magnetresonanz- und Positronenemissionstomographie haben entscheidend dazu beigetragen, dass psychiatrische Erkrankungen heutzutage im Kontext funktioneller, biochemischer und feinstruktureller Veraenderungen des Gehirns verstanden werden. Im Bereich der Schizophrenieforschung gibt insbesondere die funktionelle Magnetresonanztomographie seit Mitte der 90er-Jahre wichtige Einblicke in die neurobiologischen Grundlagen schizophrener Defizitbereiche. Die vorliegende Arbeit stellt die wichtigsten fMRT-Befunde der letzten Dekade in den Bereichen Psychomotorik, visuelle bzw. akustische Informationsverarbeitung, Aufmerksamkeit und Arbeitsgedaechtnis vor. Die Betrachtung erfolgt dabei unter der besonderen Beruecksichtigung aktueller methodischer Ansaetze wie der Darstellung von Therapieeffekten und der funktionellen Charakterisierung psychiatrischer Risikogene. (orig.)

The significance of diagnostic MRI for visualisation of trauma-induced cervical nerve root avulsion. Case report; Die Bedeutung der MRT-Diagnostik zur Darstellung traumatisch bedingter zervikaler Wurzelausrisse. Kasuistik

Energy Technology Data Exchange (ETDEWEB)

Muth, C P [Carl-Thiem-Klinikum, Cottbus (Germany). Inst. fuer Radiologie; Biemelt, F [Carl-Thiem-Klinikum, Cottbus (Germany). Inst. fuer Radiologie; Kamenz, M [Carl-Thiem-Klinikum, Cottbus (Germany). Inst. fuer Radiologie

1996-11-01

The article is intended to show the value of MRI for diagnostic visualisation and evaluation of posttraumatic nerve root avulsion as a brachial plexus injury. (orig./MG) [Deutsch] Das Ziel der Arbeit besteht in der Darstellung des Wertes der MRT-Diagnostik bei der Abklaerung traumatischer Wurzelausrisse im Bereich des Plexus brachialis. (orig./MG)

Scintigraphic evaluation of gastric emptying and motility; Nuklearmedizinische Diagnostik der Magenmotilitaet

Energy Technology Data Exchange (ETDEWEB)

Linke, R. [Klinik und Poliklinik fuer Nuklearmedizin, Ludwig-Maximilians-Univ. Muenchen (Germany)

2003-06-01

The stomach consists of two functionally distinct parts. The fundus and upper corpus mainly serve as a reservoir and exert primarily a tonic activity, which presses ingesta towards the antrum and duodenum. The phasic contractility of the lower corpus and antrum cause mechanical breakdown and mixing of the food particels. A complex regulation of these mechanisms provides a regular gastric emptying. Various disorders such as diabetes mellitus, mixed connective tissue diseases, gastritis, tumors, dyspeptic disorders but also drugs and gastric surgery may influence or impair gastric function and may cause typical symptoms such as upper abdominal discomfort, bloating, nausea and vomiting. However, the interpretation of gastrointestinal symptoms often is difficult. Radionuclide studies of gastric emptying and motility are the most physiologic tools available for studying gastric motor function. Gastric scintigraphy is non-invasive, uses physiologic meal and is quantitative. Emptying curves generated from the gastric ROI offer information whether a disorder is accompanied by a regular, fast or slow gastric emptying. Data on gastric contractions (amplitude and frequency) provide additional information to results obtained by conventional emptying studies. Depending on the underlying disorder, gastric emptying and peristalsis showed both corresponding and discrepant findings. Therefore, both parameters should be routinely assessed to further improve characterisation of gastric dysfunction by scintigraphy. (orig.) [German] Proximaler und distaler Magen haben funktionell unterschiedliche Aufgaben. Waehrend der proximale Magen die Nahrung voruebergehend speichert und ueber die Generierung eines gastroduodenalen Druckgefaelles eine fraktionierte Entleerung in den Duenndarm bewirkt, dient die Peristaltik des distalen Magens der Durchmischung und Zerkleinerung des Speisebreis. Eine komplexe hormonelle, humorale und nervale Regulation dieser ineinandergreifenden Funktionen

DMSA-scintigraphy in paediatrics: is the evaluation of the geometric mean necessary for the calculation of the differential renal function?; Partialfunktionsberechnung der Nieren mit DMSA in der Paediatrie: ist fuer die Bestimmung das geometrische Mittel notwendig?

Energy Technology Data Exchange (ETDEWEB)

Porn, U.; Alalp, S.; Fischer, S.; Dresel, S. [Klinik und Poliklinik fuer Nuklearmedizin, Klinikum der Ludwig-Maximilians-Univ. Muenchen (Germany); Rossmueller, B. [Inst. fuer Radiologische Diagnostik, Klinikum der Ludwig-Maximilians-Univ. Muenchen (Germany); Hahn, K. [Klinik und Poliklinik fuer Nuklearmedizin, Klinikum der Ludwig-Maximilians-Univ. Muenchen (Germany); Inst. fuer Radiologische Diagnostik, Klinikum der Ludwig-Maximilians-Univ. Muenchen (Germany)

2001-08-01

cases with an obvious anatomical abnormality. (orig.) [German] Bei der statischen Nierenfunktionsszintigraphie mit Tc-99m-Dimercaptobernsteinsaeure (DMSA) wird zur moeglichst exakten Bestimmung der seitengetrennten Partialfunktion (PF) die Berechnung des geometrischen Mittels aus dorsaler und ventraler Projektion empfohlen. Ziel unserer Untersuchung war es, die allein aus der dorsalen Projektion ermittelte Partialfunktion (PF{sub dors}) mit der aus dem geometrischen Mittel berechneten PF (PF{sub geom}) zu vergleichen, um die Notwendigkeit der zusaetzlichen ventralen Projektion zu ueberpruefen. Methode: Es wurden 164 DMSA-Untersuchungen von 151 Kindern (86 w, 65 m) mit einem Alter von 16 d bis 16 a (4,7 {+-} 3,9 a) ausgewertet. Die Akquisition erfolgte mit einer Doppelkopfkamera aus ventraler und dorsaler Projektion (Picker Prism 2000 XP, LEUHR, Matrix: 256 x 256, 300 kcts/view, Zoom: 1,6-2,0). Mittels ROI-Auswertung wurden die Hintergrund-korrigierten Zaehlraten der beiden Nieren von ventral und dorsal bestimmt und die dorsalen Zaehlratenverhaeltnisse mit dem geometrischen Mittel (SQR[Cts{sub dors} x Cts{sub ventr}]) verglichen. Ergebnisse: Die PF{sub dors} ergab statistisch signifikant niedrigere Werte fuer die rechte Niere (bzw. entsprechend hoehere Werte fuer die linke Niere) im Vergleich zur PF{sub geom} (p<0,01). Die mittlere Differenz zwischen der PF{sub geom} und der PF{sub dors} betrug 1,5 {+-} 1,4%. Nur in 6/164 Faellen (3,7%) ergab sich ein Unterschied von {>=}5% (5,0-9,5%). Bei 3 dieser 6 Faelle lag die mit der PF{sub dors} unterschaetzte Niere (2 x links, 1 x rechts) kaudal dystop. Die uebrigen 3 Patienten mit einer Differenz von >5% zeigten keine Lage- oder Strukturanomalie. Schlussfolgerung: Die Berechnung der Partialfunktion ausschliesslich aus den dorsalen Projektionen fuehrt im Vgl. zur Berechnung durch das geometrische Mittel zu einer Unterschaetzung der PF der rechten Niere im Vergleich zur linken Niere. Dieser Effekt fuehrt jedoch bei orthotop

Incidence and significance of small focal liver lesions on MRI; Haeufigkeit und Bedeutung von kleinen fokalen Leberlaesionen in der MRT

Energy Technology Data Exchange (ETDEWEB)

Kreft, B.; Pauleit, D.; Bachmann, R.; Conrad, R.; Kraemer, A.; Schild, H.H. [Bonn Univ. (Germany). Radiologische Klinik

2001-05-01

Analysis of the frequency and significance of small focal liver lesions ({<=} 2 cm) detected on MRI in the presence or absence of a history of malignancy. Methods: 628 MRI examinations of the liver performed during 1994 - 1996 were evaluated. The inclusion criterion into the study was the detection of a focal liver lesion with a size {<=} 2 cm. The frequency, the size, the diagnostic proof, and the differential diagnosis of the focal liver lesions were analysed with regard to the patients history of a known malignant tumor. Results: Overall, 179 of the 628 patients (28.5%) had focal liver lesions {<=} 2 cm (n = 338). 58.9% of the lesions could be classified based upon follow-up studies by ultrasound, CT or MRI, or by biopsy. The remaining 41.1% of the lesions could not be classified due to the absence of follow-up examinations. 57.3% of all proven lesions were benign and 42.7% were malignant. A history of a malignant tumor was present in 76.7% of all patients with small liver lesions; however, lesions were benign in these patients in 50.6% of the cases. In patients with no known history of a malignancy, 75% of the lesions were benign and 25% were malignant. However, these malignant lesions were in 10/11 cases hepatocellular carcinomas in patients with liver cirrhosis. (orig.) [German] Analyse der Haeufigkeit und der Bedeutung von kleinen Leberlaesionen ({<=} 2 cm) in der MRT in Abhaengigkeit einer vorbestehenden Tumoranamnese. Methode: Es wurden insgesamt 628 MRT-Untersuchungen der Leber aus dem Zeitraum von 1994-1996 ausgewertet. Einschlusskriterium in die Studie war der Nachweis von Leberlaesionen mit einer Groe paragraph e {<=} 2 cm, wobei die Haeufigkeit, die Groe paragraph enverteilung, die Diagnosesicherung und die Differenzialdiagnose in Abhaengigkeit von der Anamnese einer Tumorerkrankung untersucht wurden. Ergebnisse: Insgesamt wiesen 179 der 628 Patienten (28,5%) fokale Leberlaesionen {<=} 2 cm (n = 338) auf. 58,9% der Laesionen konnten aufgrund von

Kino filmų titrai kaip kalbų mokymosi priemonė. Untertitel als Mittel zum Fremdsprachenerwerb

Directory of Open Access Journals (Sweden)

Alina Baravykaitė

2007-01-01

Full Text Available Das in den letzten Jahren spürbare Bestreben der litauischen Gesetzgeber, Untertitelung von Fernsehfilmen zwecks Fremdsprachenerwerb gesetzlich anzuordnen, löste eine Auseinandersetzung in der Öffentlichkeit aus, die sich in der Presse sowie im Internet widerspiegelt und als Anstoß zum vorliegenden Beitrag dient. Diese Arbeit stellt den Versuch dar, die Möglichkeiten und Grenzen der Untertitelung als eines Mittels zum Fremdsprachenerwerb zu untersuchen. Auf Grund der fehlenden wissenschaftlichen Forschungen in diesem Bereich sollen dabei empirische Betrachtungen und die vergleichende Textanalyse von Original und Übersetzung als Hilfe dienen. Auch wenn die Relevanz der Untertitelung für den Fremdsprachenerwerb nicht bestreitbar ist, ist sie aber zugleich nicht zu überschätzen: Durch die lediglich für diese Form der audiovisuellen Übersetzung charakteristischen Merkmale (kurze Einblendezeit, kondensierte Sprache und begrenzte Übertragungsmöglichkeiten von Realia-Begriffen, Phraseologismen, Intertextualismen, dem Wortspiel etc. bleiben dem Zuschauer oft sprachliche Stilmittel vorenthalten und der in allen Übersetzungsbereichen vorkommende unausweichliche Sinn- und Wirkungsverlust des Originals wird erheblich verstärkt. Anbetracht der erwähnten Aspekte und der häufigen fehlerhaften Übersetzungen sollen Untertitel nur als Hilfsmittel beim Fremdsprachenerwerb angewendet werden, wobei herkömmliche Lehr- und Lernstrategien von Fremdsprachen in den Vordergrund treten müssen.

MRI in dementia-type diseases; MRT bei demenziellen Erkrankungen

Energy Technology Data Exchange (ETDEWEB)

Bodea, S.V.; Muehl-Benninghaus, R. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg (Germany)

2015-05-01

Dementia-inducing conditions represent a leading cause of disability and are a major health concern in industrialized countries. The burden these conditions put on society is certain to rise in the context of an ever-increasing elderly population. As these conditions feature an insidious onset and overlapping clinical features, imaging is a powerful tool in refining the diagnosis and assessing the progression of dementing conditions. The radiologist needs to be aware of and be able to detect underlying pathologies which could be reversible. Furthermore, imaging is important not only in excluding other pathologies but also in improving diagnostic accuracy. This article presents the typical clinical presentations as well as magnetic resonance imaging (MRI) features of the degenerative and the non-degenerative causes of dementia. The focus is on the core knowledge for MRI diagnostics in dementing conditions and a brief presentation of the latest MRI techniques which may become a part of standard imaging protocols in the future. (orig.) [German] Demenzielle Erkrankungen gehoeren in den Industrielaendern zu den haeufigsten Ursachen fuer Beeintraechtigungen im Alltag. Durch eine stetig alternde Population nimmt auch die Belastung fuer die Gesellschaft immer weiter zu. Bei haeufig schleichendem Symptombeginn sowie sich ueberlappender Klinik mit anderen Krankeitsbildern kann die Bildgebung ein gutes Werkzeug zur Praezisierung der Diagnose und Beurteilung eines Progresses sein. Der Radiologe sollte andere und reversible Pathologien erkennen und von demenztypischen Veraenderungen abgrenzen koennen. Dieser Artikel beschreibt typische klinische Symptome und auch bildmorphologische Veraenderungen verschiedener Demenzformen, die durch neurodegenerative und nichtdegenerative Ursachen bedingt sein koennen. Ausserdem werden aktuellste MRT-Techniken vorgestellt. Diese koennten kuenftig im Standartprotokoll zur Bildgebung bei der Abklaerung demenzieller Syndrome verankert sein. (orig.)

The effect of highly potent, static magnetic fields used in magnetic resonance tomography (MRT) on the red-green vision of man

International Nuclear Information System (INIS)

Hancken, G.C.W.

1989-01-01

The ability of red-green differentiation before and after MRT exposure to a static magnetic field of a potency of 0.5 Tesla was examined in a total of 32 volunteers and contrastet to that of 128 further test persons before and after CT, linear accelerator irradiation and ultrasonography as well as to findings revealed in a control group. The greatest number of significant colour misjudgements was seen in the MRT group, where 57% of patients had deteriorated colour vision. Volunteers treated at CT units or linear accelerators also showed deviations from the normal red-green vision in 48.5% and 38.7% of cases. In the ultrasound and control groups, no more than 25% and 13.3% of the values measured using the anomaloscope suggested changes from normal. Exposure to a 0.5 Tesla magnetic field led to slight shifts in colour vision for a great number of patients. These appear to be brought about by light-sensitive photoreceptors in the retinal cone cells that respond to magnetic field influences. Theories about the underlying mechanisms are explained and discussed. The results obtained in the ultrasound and control groups have, however, also made evident that some individuals are prone to changes in colour vision without having been exposed to any measurable physical influences. These appear to be chiefly attributable to factors like stress. It would be most interesting to know to which extent study results such as these are distorted by personal perceptions and mental factors. (orig./MG) [de

Diagnosis and differential diagnosis of Graves' orbitopathy in MRI; Diagnose und Differenzialdiagnose der endokrinen Orbitopathie in der MRT

Energy Technology Data Exchange (ETDEWEB)

Daubner, D.; Spieth, S.; Engellandt, K.; Kummer, R. von [Universitaetsklinikum Carl Gustav Carus, Technische Universitaet Dresden, Abteilung Neuroradiologie, Institut und Poliklinik fuer Radiologische Diagnostik, Dresden (Germany)

2012-06-15

Imaging of Graves' orbitopathy (GO) includes radiological and nuclear medicine procedures. Depending on the method used they provide information about the distribution and activity of the disease. Magnetic resonance imaging (MRI) is not only a helpful tool for making the diagnosis it also enables differentiation of the active and inactive forms of GO due to intramuscular edema. The modality is therefore appropriate to evaluate the disease activity and the course of therapy. The disease leads to the typical enlargement of the muscle bodies of the extraocular muscles. The inferior rectus, medial rectus and levator palpebrae muscles are mostly involved. Signal changes of the intraconal and extraconal fat tissue are possible and a bilateral manifestation is common. The differential diagnosis includes inflammatory diseases and tumors, of which orbital pseudotumor (idiopathic, unspecific orbital inflammation), ocular myositis and orbital lymphoma are the most important. The specific patterns (localization, involvement of orbital structures and signal changes) can be differentiated by MRI. (orig.) [German] Die Bildgebung der endokrinen Orbitopathie (EO) umfasst radiologische und nuklearmedizinische Verfahren, die je nach Methode Aussagen zur Verteilung und Aktivitaet der Erkrankung liefern. Die Magnetresonanztomographie (MRT) ist nicht nur zur Diagnosestellung hilfreich, sondern auch in der Lage, die aktive von der inaktiven Form anhand des intramuskulaeren Oedems zu unterscheiden. Das Verfahren eignet sich deshalb auch zur Aktivitaetsbeurteilung und zur Bewertung einer Therapie im Verlauf. Die Erkrankung fuehrt zu einer typischen Verdickung des Muskelbauchs der extraokulaeren Augenmuskeln, wobei die Mm. rectus inferior, rectus medialis und levator palpebrae am haeufigsten betroffen sind. Signalveraenderungen des intra- und extrakonalen Fettgewebes sind moeglich, und eine bilaterale Manifestation ist haeufig. Die Differenzialdiagnose umfasst neben anderen

Value of magnetic resonance imaging in diffuse liver diseases; Stellenwert der MRT bei diffusen Lebererkrankungen

Energy Technology Data Exchange (ETDEWEB)

Schramm, N.; D' Anastasi, M.; Reiser, M.F.; Zech, C.J. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany)

2012-08-15

Diffuse liver diseases show an increasing prevalence. The diagnostic gold standard of liver biopsy has several disadvantages. There is a clinical demand for non-invasive imaging-based techniques to qualitatively and quantitatively evaluate the entire liver. Ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used. Steatosis: chemical shift and frequency selective imaging, MR spectroscopy (MRS). Hemochromatosis: MR-based iron quantification. Fibrosis: MR elastography, diffusion, intravoxel incoherent motion (IVIM) and MR perfusion. T1-weighted in and opposed phase imaging is the clinically most frequently used MR technique to noninvasively detect and quantify steatosis. New methods for quantification that are not influenced by confounders like iron overload are under investigation. The most sensitive method to measure the fat content of the liver is MRS. As data acquisition and analysis remain complex and there is no whole organ coverage, MRS of the liver is not a routine method. With an optimized protocol incorporating T2* sequences, MRI is the modality of choice to quantify iron overload in hemochromatosis. Standard MR sequences cannot depict early stages of liver fibrosis. Advanced MR techniques (e.g. elastography, diffusion, IVIM and perfusion) for noninvasive assessment of liver fibrosis appear promising but their role has to be further investigated. (orig.) [German] Die Praevalenz diffuser Lebererkrankungen nimmt zu. Der klinische Goldstandard, die Leberbiopsie, hat zahlreiche Nachteile. Es besteht ein Bedarf an bildgebenden Verfahren zur nichtinvasiven qualitativen und quantitativen Beurteilung der gesamten Leber bei diesen Erkrankungen. Hier sind Ultraschall, CT und MRT zu nennen. Steatosis: Chemical-shift- und frequenzselektive Bildgebung, MR-Spektroskopie (MRS) zur Fettquantifizierung. Haemochromatose: MR-basierte Eisenquantifizierung. Fibrose: MR-Elastographie, Diffusion, ''intravoxel incoherent motion

MR of the muskuloskeletal system: A review; MR-Tomographie (MRT) des Skeletts, der peripheren Weichteile und der Gelenke - aktuelle Uebersicht

Energy Technology Data Exchange (ETDEWEB)

Bohndorf, K. [Zentralklinikum Augsburg (Germany). Klinik fuer Diagnostische und Neuroradiologie; Kretschmer, K.H. [Zentralklinikum Augsburg (Germany). Klinik fuer Diagnostische und Neuroradiologie

1996-05-01

The skeleton, the peripheral soft tissues, and the joints have become important indications to use MRI routinely. About 25-35% of daily examinations focus on these anatomic sites. Superior contrast resolution, the option of different imaging planes, and the unsurpassed visualization of bone marrow, fibrous and hyaline cartilage, ligaments, and tendons are the reasons for the overwhelming success of this imaging method. MRI often provides the direct way to diagnosis. More and more the so-called `step by step` approach to diagnosis by imaging methods is being abandoned in favor of the primary use of MRI. The present survey summarizes the main indications for MRI in the field of the musculoskeletal system, in adults as well as in children. Special topics like tumors, inflammation, ischemia, and trauma are discussed. Some anatomic sites like the carpal joint, the shoulder, and the knee are presented in more detail. (orig.) [Deutsch] Eine Vielzahl von Fragestellungen zu wesentlichen Indikationen der MR-Tomographie am Skelett, den peripheren Weichteilen und den Gelenken haben sich in der taeglichen Praxis entwickelt. Durchschnittlich 25-35% der taeglichen Untersuchungen betreffen diesen Themenkreis. Ueberlegene Kontrastaufloesung, die Darstellung in beliebig waehlbaren Ebenen und die unuebertroffene Visualisierung von Strukturen wie Knochenmark, fibroesem und hyalinem Knorpel, Ligamenten und Sehnen, sind die Ursache der raschen Verbreitung der Methode. Die MRT stellt haeufig den direkten Weg zur Diagnose dar und ersetzt zunehmend die sog. `Stufendiagnostik` und damit Methoden wie die Computertomographie, Arteriographie oder auch Skelettszintigraphie. In der vorliegenden Uebersicht werden wesentliche, heute als gesichert anzusehenden Anwendungsgebiete der MRT bei Kindern und Erwachsenen zusammengefasst. Die Arbeit gibt einen Ueberblick ueber spezielle Fragestellungen bei Tumoren, Entzuendungen, Ischaemie und traumatischen Fragestellungen. Eine Reihe von anatomischen

Development and validation of a new LBM-MRT hybrid model with enthalpy formulation for melting with natural convection

Energy Technology Data Exchange (ETDEWEB)

Miranda Fuentes, Johann [Université de Lyon, CNRS, UMR5008, F-69622 Villeurbanne (France); INSA-Lyon, CETHIL, F-69621 Villeurbanne (France); Kuznik, Frédéric, E-mail: frederic.kuznik@insa-lyon.fr [Université de Lyon, CNRS, UMR5008, F-69622 Villeurbanne (France); INSA-Lyon, CETHIL, F-69621 Villeurbanne (France); Johannes, Kévyn; Virgone, Joseph [Université de Lyon, CNRS, UMR5008, F-69622 Villeurbanne (France); Université Lyon 1, CETHIL, F-69622 Villeurbanne (France)

2014-01-17

This article presents a new model to simulate melting with natural convection of a phase change material. For the phase change problem, the enthalpy formulation is used. Energy equation is solved by a finite difference method, whereas the fluid flow is solved by the multiple relaxation time (MRT) lattice Boltzmann method. The model is first verified and validated using the data from the literature. Then, the model is applied to a tall brick filled with a fatty acid eutectic mixture and the results are presented. The main results are (1) the spatial convergence rate is of second order, (2) the new model is validated against data from the literature and (3) the natural convection plays an important role in the melting process of the fatty acid mixture considered in our work.

MRT-lattice Boltzmann computations of natural convection and volumetric radiation in a tilted square enclosure

Energy Technology Data Exchange (ETDEWEB)

Moufekkir, F.; Moussaoui, M.A.; Mezrhab, A. [Laboratoire de Mecanique and Energetique, Faculte des sciences, Departement de physique 60000 Oujda (Morocco); Lemonnier, D. [Institut Pprime, CNRS-ENSMA-Univ. Poitiers, ENSMA, BP 40109, 86961 Futuroscope Chasseneuil cedex (France); Naji, H. [Universite Lille Nord de France, F-59000 Lille (France); Laboratoire Genie Civil and geo-Environnement - LGCgE- EA 4515, UArtois/FSA Bethune, F-62400 Bethune (France)

2012-04-15

A numerical analysis is carried out for natural convection while in an asymmetrically heated square cavity containing an absorbing emitting medium. The numerical approach adopted uses a hybrid thermal lattice Boltzmann method (HTLBM) in which the mass and momentum conservation equations are solved by using multiple relaxation time (MRT) model and the energy equation is solved separately by using the finite difference method (FDM). In addition, the radiative transfer equation (RTE) is treated by the discrete ordinates method (DOM) using the S8 quadrature to evaluate the source term of the energy equation. The effects of parameters such as the Rayleigh number Ra, the optical thickness {tau} and the inclination angle {phi}, are studied numerically to assess their impact on the flow and temperature distribution. The results presented in terms of isotherms, streamlines and averaged Nusselt number, show that in the absence of the radiation, the temperature and the flow fields are centro-symmetric and the cavity core is thermally stratified. However, radiation causes an overall increase in temperature and velocity gradients along both thermally active walls

Imaging of bacterial infections of the sacroiliac joint; Darstellung bakterieller Infektionen im Sakroiliakalgelenk

Energy Technology Data Exchange (ETDEWEB)

Groves, C.; Cassar-Pullicino, V. [Radiology Department, Robert Jones and Agnes Hunt Orthopaedic Hospital Oswestry (United Kingdom)

2004-03-01

eindeutigen praedisponierenden Faktoren festzustellen. Die Zeitspanne zwischen dem ersten Auftreten der Symptome und der endgueltigen Diagnose ist in der Regel erheblich. Das klinische Bild ist oft unspezifisch und variabel, und die schwierige klinische Beurteilung kann darauf beruhen, dass es sich um einen relativ selten auftretenden Zustand handelt. Ausserdem ist die klinische Untersuchung der Sakroiliakalgelenke sehr problematisch. Die Diagnose basiert auf Anamnese und klinischen Befunden. Sie weisen zusammen mit Blutkultur und/oder einem ev. Gelenkspunktat auf eine Infektion im Sakroiliakalgelenk hin. Das haeufigste klinische Symptom bei bakteriellen Infektionen sind Schmerzen im unteren Teil der Wirbelsaeule oder im Gesaess. Mittels einer STIR-Sequenz, welche die Sakroiliakalgelenke gut darstellt, koennen Pathologien relativ einfach und aeusserst frueh entdeckt werden. Von allen bildgebenden Verfahren ist MRT daher die Methode der Wahl bezueglich Sensitivitaet und Spezifitaet. Falls eine MRT aufgrund geringer Verfuegbarkeit nicht durchfuehrbar ist, sollte als zweite Methode der Wahl die 3-Phasenknochenszintigraphie durchgefuehrt werden. Der konventionellen Roentgendiagnostik kommt weder in der Frueh- noch Verlaufsdiagnostik eine entscheidende Rolle zu. Eine CT-gefuehrte Gelenkpunktion kann in unklaren Faellen die diagnostische Treffsicherheit erhoehen. Eine Therapiekontrolle ist am besten mittels Tc99m Blutpool-Untersuchungen moeglich. Eine hochgradige klinische Verdachtsdiagnose und eine fruehe MRT-Untersuchung sind die wesentliche Voraussetzung fuer die exakte Diagnose einer bakteriellen Sakroiliitis. (orig.)

Air-electron stream interactions during magnetic resonance IGRT. Skin irradiation outside the treatment field during accelerated partial breast irradiation

Energy Technology Data Exchange (ETDEWEB)

Park, Jong Min [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Advanced Institutes of Convergence Technology, Robotics Research Laboratory for Extreme Environments, Suwon (Korea, Republic of); Shin, Kyung Hwan; Wu, Hong-Gyun [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiation Oncology, Seoul (Korea, Republic of); Kim, Jung-in; Park, So-Yeon; Kim, Jin Ho [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Jeon, Seung Hyuck [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Choi, Noorie [Seoul National University College of Medicine, Department of Radiation Oncology, Seoul (Korea, Republic of)

2018-01-15

ein Elektronenstrahl ausserhalb der Therapiefelder entstehen. In dieser Studie wurde fuer akzelerierte Teilbrustbestrahlungen (APBI) diese Strahlung abgeschirmt und naeher untersucht. Fuer diese Studie wurden prospektiv 20 Patientinnen ausgewaehlt, die eine APBI mit einer MRT-gefuehrten Strahlentherapie (MR-IGRT) erhielten. Die Bestrahlung erfolgte mit einem Tri-Kobalt-System, das mit einem Magnetresonanztomographen kombiniert war (ViewRay). Es wurden jeweils 10 Fraktionen mit einer Einzeldosis von 3,85 Gy und der resultierenden Gesamtdosis von 38,5 Gy appliziert. Zur Reduktion der Hautdosis wurden pro Patientin 2 unterschiedliche Therapieplaene fuer jeweils 5 Fraktionen mit unterschiedlichen Tragarmwinkeln eingesetzt. Zur Abschirmung des unerwuenschten Elektronenstrahls ausserhalb der Strahlenfelder wurde ein 1 cm starker Bolus vor dem Kiefer sowie vor der ipsilateralen Schulter und dem Arm der Patientin positioniert. Vor dem Bolusmaterial (Richtung Brust) und hinter dem Bolusmaterial (Richtung Kopf) wurden EBT3-Radiochromroentgenfilme befestigt, um die ein- und austretende Dosis zu messen. Die Abhaengigkeiten der Messwerte von der Lokalisation des bestrahlten Tumors, der Bestrahlungszeit und der Tumorgroesse wurden untersucht. Fuer jeweils eine Strahlenfraktion wurden auf den Roentgenfilmen vor dem Bolusmaterial (Richtung Brust) die von den einzelnen Isodosen eingeschlossenen Flaechen vermessen: die 14 %-Isodosis (0,54 Gy) umschloss im Mittel eine Flaeche von 3,6 cm{sup 2}, die 12 %-Isodosis (0,46 Gy) im Mittel 10,4 cm{sup 2} und die 10 %-Isodosis (0,39 Gy) im Mittel 21,4 cm{sup 2}. Die Roentgenfilme hinter dem Bolusmaterial zeigten hingegen keine signifikante Dosisbelastung an. Statistisch signifikante, aber nur geringe Korrelationen wurden zwischen der Dosisbelastung und den Behandlungszeiten beobachtet. Werden Brustkrebspatientinnen mit einem MRT-gefuehrten Tri-Kobalt-Bestrahlungsgeraet behandelt, kann durch eine Wechselwirkung von Strahlenquelle und

MRI of esophagus. N staging and more...; MRT des Oesophagus. N-Staging und mehr...

Energy Technology Data Exchange (ETDEWEB)

Krupski-Berdien, G. [Krankenhaus Reinbek St.-Adolf- Stift, Abteilung fuer diagnostische und interventionelle Radiologie, Reinbek (Germany)

2007-02-15

Esophageal disease is common. Fluoroscopy with or without fast cine-sequences is able to depict swallowing dynamics precisely and therefore is used in cases with swallowing disturbance, achalasia or diverticula etc. It is performed in addition to primary endoscopy. There is no evidence based indication for MRI in these settings as it is not to rule out postsurgical fistula and incompetence. Endoscopy and endosonography are gold standard for the depiction as well as staging of esophageal tumors hence differentiation of the esophageal wall layers and detection of suspicious lymph nodes is possible. And from both, biopsies may be taken. New techniques as OCT (optical coherence tomography) can demonstrate in situ carcinoma and therefore helps to decide for limited treatments as mucosectomy. For today multimodular treatment strategies in esophageal carcinoma the T-stage will lead to the treatment decision whereas the nodal-stage will give information about the prognosis. As a matter of fact endoscopy is unable to pass a stenosis esophageal tumor in up to 50% of the cases and will therefore not be able to give precise information on both T- and N-stage resulting in a good indication for MRI. Fetal MRI of the chest is a new topic in which MRI seems to be superior to ultrasonography. (orig.) [German] Erkrankungen des Oesophagus sind haeufig. Die Durchleuchtungsuntersuchung, ggf. mit schnellen Cinesequenzen, vermag exakt die Dynamik des Schluckakts darzustellen und wird regelhaft bei Fragestellungen wie ''Verschlucken'' und ''Globusgefuehl'', Verdacht auf Achalsie etc. sowie bei der Suche nach Divertikeln eingesetzt und ergaenzt die primaere Endoskopie. Die MRT besitzt hier derzeit keinen gesicherten Stellenwert - ebenso wie bei der haeufigsten Indikation zur Oesophagus-Breischluck-Untersuchung in der Klinik, der Frage nach Paravasation und Fistelung nach oesophagogastralen Eingriffen. Die exakten Lokalisation eines Oesophagustumors

CT and MRI normal findings; CT- und MRT-Normalbefunde

Energy Technology Data Exchange (ETDEWEB)

Moeller, T.B.; Reif, E. [Caritas-Krankenhaus, Dillingen (Germany)

1998-07-01

This book gives answers to questions frequently heard especially from trainees and doctors not specialising in the field of radiology: Is that a normal finding? How do I decide? What are the objective criteria? The information presented is three-fold. The normal findings of the usual CT and MRI examinations are shwon with high-quality pictures serving as a reference, with inscribed important additional information on measures, angles and other criteria describing the normal conditions. These criteria are further explained and evaluated in accompanying texts which also teach the systematic approach for individual picture analysis, and include a check list of major aspects, as a didactic guide for learning. The book is primarily intended for students, radiographers, radiology trainees and doctors from other medical fields, but radiology specialists will also find useful details of help in special cases. (orig./CB) [German] Normalbefunde sind die haeufigsten Befunde ueberhaupt. Also kein Problem? Doch. Besonders Radiologen in der Ausbildung und Aerzte aus anderen Fachgebieten stellen sich immer wieder die entscheidende Frage: Ist das normal? Woran kann ich das erkennen? Wie kann ich das objektivieren? Dieses Buch leistet dreierlei: 1. Es zeigt klassische Normalbefunde der gaengigen CT- und MRT-Untersuchungen in hoher Abbildungsqualitaet als Referenz. Direkt in die Aufnahmen eingezeichnet sind wichtige Daten: Masse, Winkel und andere Kriterien des Normalen. Sie werden im Text nochmals zusammengefasst, erklaert und bewertet. 2. Es lehrt die Systematik der Bildbetrachtung - wie schaue ich mir ein Bild an, welche Strukturen betrachte ich in welcher Reihenfolge und worauf muss ich dabei besonders achten? Dies alles in Form einer uebersichtlichen Checkliste zu jeder Aufnahme. 3. Es gibt eine Befundformulierung vor, die sich wiederum an dem Schema der Bildanalyse orientiert, alle Kriterien des Normalen definiert und dadurch auch ein wichtiges didaktisches Element darstellt

Muscle injuries in athletes. The value of magnetic resonance imaging; Muskelverletzungen des Sportlers. Stellenwert der MRT-Bildgebung

Energy Technology Data Exchange (ETDEWEB)

Lueckerath, C. [Universitaetsklinikum Heidelberg, Abteilung fuer Neuroradiologie, Heidelberg (Germany); Rehnitz, C. [Universitaetsklinikum Heidelberg, Diagnostische und Interventionelle Radiologie, Heidelberg (Germany)

2017-12-15

Competitive sports yield high demands on the musculoskeletal system, accordingly muscle injuries are a common complication. Early imaging clarification of the muscles in cases of a trauma is essential in order to define the exact location of the lesion, the affected muscles, the extent and the degree of the injury as well as to define possible concomitant complications. In the case of a professional athlete, the assessment made by MRI is important for defining the individually required resting period for a riskless resumption of the sporting activities. (orig.) [German] Der Leistungssport stellt grosse Anforderungen an den Bewegungsapparat, entsprechend sind muskulaere Verletzungen eine haeufige Komplikation. Eine fruehe bildgebende Darstellung der Muskulatur im Falle eines Traumas ist essenziell, um die Lokalisation, die beteiligten Muskeln, das Ausmass sowie moegliche Komplikationen exakt zu definieren. Im Falle des Profisportlers ist insbesondere die MRT-Stadieneinteilung wichtig fuer die Festlegung der individuell notwendigen Ruhezeit bis zur risikofreien Wiederaufnahme der Aktivitaet. (orig.)

One-year follow-up of neuropsychology, MRI, rCBF and glucose metabolism (rMRGlu) in cerebral microangiopathy

Energy Technology Data Exchange (ETDEWEB)

Sabri, O.; Hellwig, D.; Schreckenberger, M.; Kaiser, H.-J.; Wagenknecht, G.; Setani, K.; Reinartz, P.; Zimny, M.; Buell, U. [Department of Nuclear Medicine, Technische Univ. Aachen (Germany); Schneider, R. [Department of Neurology, Technische Univ. Aachen (Germany); Mull, M. [Department of Neuroradiology, Technische Univ. Aachen (Germany); Ringelstein, E.-B. [Department of Neurology, Muenster Univ. (Germany)

2000-07-01

Background: MRI shows lacunar infarctions (LI), deep white matter lesions (DWML) and atrophy in cerebral microangiopathy, which is said to lead to vascular dementia. In a first trial series on 57 patients with confirmed pure cerebral microangiopathy (without concomitant macroangiopathy), neuropsychological impairment and (where present) brain atrophy correlated with decreased rCBF and rMRGlu. LI and DWML did not correlate with either neuropsychological impairment or decreased rCBF/rMRGlu. This study was done one year later to detect changes in any of the study parameters. Methods: 26 patients were re-examined for rCBF, rMRGlu, LI, DWML, atrophy and neuropsychological performance (7 cognitive, 3 mnestic, 4 attentiveness tests). Using a special head holder for exact repositioning, rCBF (SPECT) and rMRGlu (PET) were measured and imaged slice by slice. White matter/cortex were quantified using MRI-defined ROIs. Results: After one year the patients did not show significant decreases in rCBF or rMRGlu either in cortex or in white matter (p>0.05), nor did any patient show LI, DWML or atrophy changes on MRI. There were no significant neuropsychological decreases (p>0.05). (orig.) [German] Ziel: In der MRT zeigen sich bei zerebraler Mikroangiopathie (ZMA) lakunaere Infarkte (LI), Deep White Matter Lesions (DWML) und Atrophie (Atr). Die sogenannte vaskulaere Demenz wurde dabei hauptsaechlich auf die Laesionen der weissen Substanz zurueckgefuehrt. In einer ersten Untersuchungsreihe waren bei 57 Patienten mit gesicherter ZMA nur neuropsychologische Defizite (Nps) und, falls vorhanden, Atr als Grundlage fuer erniedrigte rCBF/rMRGlu-Werte zu eruieren, jedoch nicht LI/DWML. Es sollte geklaert werden, ob sich im Verlauf der Erkrankung nach einem Jahr Veraenderungen dieser Parameter ergeben. Methode: 26 Patienten wurden nach einem Jahr erneut neuropsychologisch untersucht (7 kognitive, 3 mnestrische, 4 Aufmerksamkeitstests). Mittels eines speziellen Kopfhalterungssystems wurden in

MRT of the knee joint of juvenile footballers. Are there early changes in the knee due to competitive sport?

International Nuclear Information System (INIS)

Wacker, F.; Koenig, H.; Felsenberg, D.; Wolf, K.J.

1994-01-01

In a prospective study, the right knee of 21 symptom free juvenile footballers was examined by MRT (group I) and the results were compared with 12 juveniles of similar age but who did not take part in any special sorting activities (group II). A 1.5 Tesla Magnetome with an extremity coil was used. There were no abnormal changes in either group in the cruciate ligaments. The hyaline cartilage medially was about 10% thicker than laterally in both groups but in group I it was, on average, 24.8% thicker than in group II. Increased signals in the centre of the menisci were observed in 8 members of group I and two in group II. 5 on the 8 in group I, but none in group II, also showed an increase in the joint fluid. (orig.) [de

Aorta cross-section calculation and 3D visualization from CT or MRT data using VRML

Science.gov (United States)

Grabner, Guenther; Modritsch, Robert; Stiegmaier, Wolfgang; Grasser, Simon; Klinger, Thomas

2005-04-01

Quantification of vessel diameters of artherosclerotic or congenital stenosis is very important for the diagnosis of vascular diseases. The aorta extraction and cross-section calculation is a software-based application that offers a three-dimensional, platform-independent, colorized visualization of the extracted aorta with augmented reality information of MRT or CT datasets. This project is based on different types of specialized image processing algorithms, dynamical particle filtering and complex mathematical equations. From this three-dimensional model a calculation of minimal cross sections is performed. In user specified distances, the aorta is cut in differently defined directions which are created through vectors with varying length. The extracted aorta and the derived minimal cross-sections are then rendered with the marching cube algorithm and represented together in a three-dimensional virtual reality with a very high degree of immersion. The aim of this study was to develop an imaging software that delivers cardiologists the possibility of (i) furnishing fast vascular diagnosis, (ii) getting precise diameter information, (iii) being able to process exact, local stenosis detection (iv) having permanent data storing and easy access to former datasets, and (v) reliable documentation of results in form of tables and graphical printouts.

PET-CT and PET-MRI of the prostate. From {sup 18}F-FDG to {sup 68}Ga-PSMA; PET-CT/-MRT der Prostata. Von {sup 18}F-FDG zu {sup 68}Ga-PSMA

Energy Technology Data Exchange (ETDEWEB)

Knorr, K.; Eiber, M.; Scheidhauer, K. [Technische Universitaet Muenchen, Nuklearmedizinische Klinik und Poliklinik, Klinikum rechts der Isar, Muenchen (Germany); Maurer, T. [Technische Universitaet Muenchen, Urologische Klinik und Poliklinik, Klinikum rechts der Isar, Muenchen (Germany); Wester, H.J. [Technische Universitaet Muenchen, Pharmazeutische Radiochemie, Garching (Germany)

2017-08-15

In the last few years nuclear medical diagnostics have experienced a unprecedented renaissance in the diagnostics of prostate cancer, due to the availability of hybrid imaging with positron emission tomography computed tomography (PET/CT), PET magnetic resonance imaging (PET/MRI) and single photon emission computed tomography (SPECT) CT as well as the development of prostate-specific radiopharmaceuticals. The use of fluorodeoxyglucose (FDG), which has been successfully implemented for many years in PET diagnostics, is only helpful in dedifferentiated tumors due to the biological characteristics of prostate cancer. New specific radiopharmaceuticals, such as choline-derivatives, which are incorporated into the prostate cancer cell and built into the cell membrane as well as the recently developed highly specific ligands for prostate-specific membrane antigen (PSMA) are revolutionizing prostate cancer imaging and (re-) staging. The {sup 68} Ga-labeled PSMA ligands for PET-CT and PET-MRI are highly specific tracers for primary diagnostics and detection of metastases of prostate carcinoma. In risk patients, which includes patients with intermediate and high-risk tumors, they have largely replaced choline-based PET-CT, especially in the case of very low PSA values <0.5 ng/ml in the diagnostics of recurrence. The use in the primary diagnostics as PET-MRI, also in combination with multiparametric MRI (mpMRI), is promising with respect to early diagnostics and image fusion-assisted biopsy as well as surgery and irradiation planning. (orig.) [German] Die nuklearmedizinische Diagnostik hat in den letzten Jahren bei der Bildgebung des Prostatakarzinoms eine rasante Entwicklung erlebt, sowohl aufgrund der verfuegbaren Hybridbildgebung mit der Positronenemissionstomographie(PET)-CT, PET-MRT sowie der Single-photon-emission-computed-tomography(SPECT)-CT als auch durch die Entwicklung prostataspezifischer Radiopharmaka. Die in der PET-Diagnostik seit Jahren erfolgreich eingesetzte

PET in patients with clear-cut multiple chemical sensitivity (MCS); PET bei Patienten mit klar definierter multipler chemischer Sensibilitaet (MCS)

Energy Technology Data Exchange (ETDEWEB)

Bornschein, S. [Toxikologische Abt. der II. Medizinischen Klinik und Poliklinik der Technischen Univ. Muenchen, Klinikum rechts der Isar, Muenchen (Germany); Klinik und Poliklinik fuer Psychiatrie und Psychotherapie der Technischen Univ. Muenchen, Klinikum rechts der Isar, Muenchen (Germany); Hausteiner, C.; Foerstl, H. [Klinik und Poliklinik fuer Psychiatrie und Psychotherapie der Technischen Univ. Muenchen, Klinikum rechts der Isar, Muenchen (Germany); Drzezga, A.; Schwaiger, M. [Nuklearmedizinische Klinik und Poliklinik der Technischen Univ. Muenchen, Klinikum rechts der Isar, Muenchen (Germany); Bartenstein, P. [Klinik und Poliklinik fuer Nuklearmedizin, Universitaetsklinikum Mainz (Germany); Zilker, Th. [Toxikologische Abt. der II. Medizinischen Klinik und Poliklinik der Technischen Univ. Muenchen, Klinikum rechts der Isar, Muenchen (Germany)

2002-12-01

Aim: Multiple chemical sensitivity (MCS) is a controversially discussed symptom complex. Patients afflicted by MCS react to very low and generally non-toxic concentrations of environmental chemicals. It has been suggested that MCS leads to neurotoxic damage or neuroimmunological alteration in the brain detectable by positron emission tomography (PET) and single photon emission computer tomography (SPECT). These methods are often applied to MCS patients for diagnosis, although they never proved appropriate. Method: We scanned 12 MCS patients with PET, hypothesizing that it would reveal abnormal findings. Results: Mild glucose hypometabolism was present in one patient. In comparison with normal controls, the patient group showed no significant functional brain changes. Conclusion: This first systematic PET study in MCS patients revealed no hint of neurotoxic or neuroimmunological brain changes of functional significance. (orig.) [German] Ziel: Multiple chemische sensibilitaet (MCS) ist ein umstrittenes Krankheitsbild, das durch Reaktionen auf geringe, fueer Normalpersonen unschaedliche Mengen an Umweltchemikalien gekennzeichnet ist. Es wurde postuliert, dass MCS zu neurotoxischer Schaedigung bzw. neuroimmunologischer Veraenderung im Gehirn fuehrt, die mittels funktioneller bildgebender Verfahren, z. B. positronenemissionstomographie (PET), single-photon-emissions-computer-tomographie (SPECT) dargestellt werden koennte. Obwohl hierfuer kein wissenschaftlicher Beleg erbracht wurde, werden diese Methoden vielfach diagnostisch bei MCS-Patienten eingesetzt. Methode: Wir untersuchten 12 MCS-Patienten mit PET, um etwaige funktionelle Hirnveraenderungen nachzuweisen. Ergebnisse: Im Einzelvergleich war bei einem Patienten ein diskreter Glukose-Hypometabolismus in einzelnen Hirnregionen vorhanden. Im Gruppenvergleich konnte keine signifikante Abweichung von der Norm gefunden werden. Schlussfolgerung: Diese erste systematische PET-Studie bei MCS-Patienten erbrachte keinen

MRI of the musculature in patients with myalgia - indications and imaging results; MRT der Muskulatur bei Myalgien - Indikationen und Bildbefunde

Energy Technology Data Exchange (ETDEWEB)

Beese, M.S. [Universitaetsklinik Hamburg-Eppendorf (Germany). Radiologische Klinik; Winkler, G. [Universitaetsklinik Hamburg-Eppendorf (Germany). Neurologische Klinik; Maas, R. [Universitaetsklinik Hamburg-Eppendorf (Germany). Radiologische Klinik; Buechler, E. [Universitaetsklinik Hamburg-Eppendorf (Germany). Radiologische Klinik

1996-05-01

241 patients suffering from myalgic symptoms were examined by axial scans of the muscular system with T1w and STIR-sequences. All patients underwent a complete neuromuscular examination, which included an MRI guided muscle-biopsy of 203 patients. The images were retrospectively analysed as to the typical characteristics of differential diagnosis. In cases of idiopathic or bacterial/viral induced myositis, primary vasculitis, and rhabdomyolysis, edematous changes of the muscles could always be found. Abscesses were only found in bacterial myositis. In cases of poly- and dermatomyositis as well as inclusion-body-myositis, MRI showed a uniform distribution pattern with emphasis on the quadriceps muscles. In contrast to other neuromuscular diseases in bacterial induced myositis, focal myositis, and rhabdomyolysis a strong contrast agent enhancement was seen. All patients with myalgic syndromes without any other additional neuropathological findings and 86% of the patients suffering from polymyalgia rheumatica had normal MR-findings. MRI allows a correct exclusion of an inflammatory, tumorous, or rhabdomyolitic cause of a myalgia and leads to pathognomonic findings for these diseases. Diseases belonging to the group of endocrine, toxic, or metabolic myopathies might be normal in MRI. (orig./MG) [Deutsch] Bei 241 Patienten mit myalgischen Beschwerden wurden axiale Aufnahmen der Muskulatur mit T1w- und STIR-Sequenzen angefertigt. Bei allen Patienten wurde eine vollstaendige neuromuskulaere Untersuchung durchgefuehrt, die bei 203 Patienten eine MRT-gezielte Muskelbiopsie beinhaltete. Das Bildmaterial wurde retrospektiv hinsichtlich differentialdiagnostischer Charakteristika analysiert. Bei idiopathischen und erregerbedingten Myositiden, primaeren Vaskulitiden und bei Rhabdomyolysen bestanden ohne Ausnahme oedematoese Veraenderungen der Muskulatur. Abszessformationen wurden nur bei erregerbedingten Myositiden vorgefunden. Bei Poly- und Dermatomyositiden sowie

Measurement of perfusion using the first-pass dynamic susceptibility-weighted contrast-enhanced (DSC) MRI in neurooncology. Physical basics and clinical applications; Perfusionsmessung mit der T2*-Kontrastmitteldynamik in der Neuroonkologie. Physikalische Grundlagen und klinische Anwendungen

Energy Technology Data Exchange (ETDEWEB)

Weber, M.-A.; Giesel, F.L.; Kauczor, H.-U.; Essig, M. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg (Germany). Abteilung Radiologie; Risse, F.; Schad, L.R. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg (Germany). Abteilung Medizinische Physik in der Radiologie

2005-07-01

Perfusion imaging in the central nervous system (CNS) is mostly performed using the first-pass dynamic susceptibility-weighted contrast-enhanced (DSC) MRI. The first-pass of a contrast bolus in brain tissue is monitored by a series of T2*-weighted MR images. The susceptibility effect of the paramagnetic contrast agent leads to a signal loss that can be converted, using the principles of the indicator dilution theory, into an increase of the contrast agent concentration. From these data, parameter maps of cerebral blood volume (CBV) and flow (CBF) can be derived. Regional CBF and CBV values can be obtained by region-of-interest analysis. This review article describes physical basics of DSC MRI and summarizes the literature of DSC MRI in neurooncological issues. Studies, all with relatively limited patient numbers, report that DSC MRI is useful in the preoperative diagnosis of gliomas, CNS-lymphomas, and solitary metastases, as well as in the differentiation of these neoplastic lesions from infections and tumor-like manifestations of demyelinating disease. Additionally, DSC MRI is suitable for determining glioma grade and regions of active tumor growth which should be the target of stereotactic biopsy. After therapy, DSC MRI helps better assessing the tumor response to therapy, residual tumor after therapy, and possible treatment failure and therapy-related complications, such as radiation necrosis. The preliminary results show that DSC MRI is a diagnostic tool depicting regional variations in microvasculature of normal and diseased brains. (orig.) [German] Die MRT-Perfusionsmessungen im Zentralnervensystem (ZNS) werden derzeit hauptsaechlich mit der kontrastmittelverstaerkten T2*-Dynamik durchgefuehrt, die die Passage eines schnellen Kontrastmittelbolus mit einer Serie von T2*-gewichteten MRT-Aufnahmen verfolgt und charakterisiert. Dabei wird der Signalabfall, bedingt durch den Suszeptibilitaetseffekt des paramagnetischen Kontrastmittels, mittels geeigneter

First clinical experience with extended planning and navigation in an interventional MRI unit; Erste klinische Erfahrungen mit einer erweiterten Eingriffsplanung und Navigation am interventionellen MRT

Energy Technology Data Exchange (ETDEWEB)

Moche, M.; Schneider, J.P.; Schulz, T.; Voerkel, C.; Kahn, T.; Busse, H. [Klinik und Poliklinik fuer Diagnostische Radiologie, Universitaetsklinikum Leipzig (Germany); Schmitgen, A.; Bublat, M. [Fraunhofer-Inst. fuer Angewandte Informationstechnik, St. Augustin (Germany); Trantakis, C. [Klinik und Poliklinik fuer Neurochirurgie, Universitaetsklinikum Leipzig (Germany); Bennek, J. [Klinik und Poliklinik fuer Kinderchirurgie, Univ. Leipzig (Germany)

2004-07-01

Purpose: To present an advanced concept for patient-based navigation and to report on our first clinical experience with interventions in the cranium, of soft-tissue structures (breast, liver) and in the musculoskeletal system. Materials and Methods: A PC-based navigation system was integrated into an existing interventional MRI environment. Intraoperatively acquired 3D data were used for interventional planning. The information content of these reference data was increased by integration of additional image modalities (e. g., fMRI, CT) and by color display of areas with early contrast media enhancement. Within 18 months, the system was used in 123 patients undergoing interventions in different anatomic regions (brain: 64, paranasal sinus: 9, breast: 20, liver: 17, bone: 9, muscle: 4). The mean duration of 64 brain interventions was compared that of 36 procedures using the scanner's standard navigation. Results: In contrast with the continuous scanning mode of the MR system (0.25 fps), the higher quality as well as the real time display (4 fps) of the MR images reconstructed from the 3D reference data allowed adequate hand-eye coordination. With our system, patient movement and tissue shifts could be immediately detected intraoperatively, and, in contrast to the standard procedure, navigation safely resumed after updating the reference data. The navigation system was characterized by good stability, efficient system integration and easy usability. Despite additional working steps still to be optimized, the duration of the image-guided brain tumor resections was not significantly longer. (orig.) [German] Ziel: Vorstellung eines erweiterten Konzepts zur patientenbasierten Navigation sowie erste klinische Bewertung der durchgefuehrten Massnahmen im Kopf, Weichteil- und muskuloskeletalen Bereich. Material und Methode: Ein PC-basiertes Navigationssystem wurde in eine vorhandene interventionelle MRT-Umgebung integriert. Intraoperativ akquirierte 3-D

How students meets and solves a novel problem : selection of cognitive mechanisms of task solution - the importance of cue constellation and individual experience

DEFF Research Database (Denmark)

Mogensen, Jesper; Malá, Hana

problemløsning, strategiselektion, kognitiv fleksibilitet, neural plasticitet, opvægstmiljø, miljøfaktorer, pædagogik, indlæring, rumlig orientering, hippocampus, præfrontal cortex, funktionel genopretning, hjerneskaderehabilitering...

Long term results of mantle irradiation(MRT) alone in 261 patients with clinical stage I-II supradiaphragmatic Hodgkin's disease

International Nuclear Information System (INIS)

Wirth, A.; Byram, D.; Chao, M.; Corry, J.; Davis, S.; Kiffer, J.; Laidlaw, C.; Quong, G.; Ryan, G.; Liew, K.

1997-01-01

Purpose: We report our results using MRT for clinical stage I-II HD and assess the value of published prognostic criteria in our study population. Pts and Methods: Between 1969 and 1994, 261 pts were treated with MRT alone for clinical stage I-II supradiaphragmatic HD. Pt characteristics: median age-30; M-54%/F-46%; stage IA-52%, IB-2%, IIA-37%, IIB-8%; histology LP-21%, NS-51%, MC-23%, other 5%; median ESR 18. CT abdomen and LAG were performed in 61% and 60% respectively. No pt had prior staging laparotomy. No pt received infradiaphragmatic RT. Central axis dose was 32 Gy-36 Gy. Univariate analysis was performed for prognostic factors for progression-free (PFS) and overall survival(OS). Outcome was assessed in favourable subsets as defined by: EORTC (v. favourable: CSIA, LP or NS histology, age < 40, female, no bulk, ESR < 50; favourable: CSI-II, age < 50, < 4 sites, no bulky mediastinal mass, ESR < 50 with no B symptoms or ESR < 30 with B symptoms); Princess Margaret Hospital (PMH) (IA-IIA, LP or NS histology, ESR < 40, age < 50, no large mediastinal mass, no E lesion). Results: 261 pts completed RT, with 5% requiring treatment interruption for toxicity. Significant factors (P<0.05) for PFS were stage, performance status, histology, B symptoms, number of sites, ESR and bulk. Significant factors (P<0.05) for OS were age, performance status, histology and B symptoms. (The results of a multivariate analysis will be presented.) Results in our study population using published prognostic criteria (in %): Thirty-six percent progressed following RT: 8% in-field; 24% out of field only (including 10% in the paraaortic/splenic region alone); 4% marginal; Fifty-seven percent of relapsed pts remain progression free after subsequent salvage treatment. Two cases of acute leukaemia, 8 cases of non-Hodgkin's lymphoma and 14 (non-skin) carcinomas occurred, of which 11 were in-field. Seventy pts have died. The cause was: HD 41%; other malignancy 20%; cardiovascular 17%; other 15

In-depth investigation of escalator riding accidents in heavy capacity MRT stations.

Science.gov (United States)

Chi, Chia-Fen; Chang, Tin-Chang; Tsou, Chi-Lin

2006-07-01

In 2000, the accident rate for escalator riding was about 0.815 accidents per million passenger trips through Taipei Metro Rapid Transit (MRT) heavy capacity stations. In order to reduce the probability and severity of escalator riding accidents and enhance the safety of passengers, the Drury and Brill model [Drury, C.G., Brill, M., 1983. Human factors in consumer product accident investigation. Hum. Factors 25 (3), 329-342] for in-depth investigation was adopted to analyze the 194 escalator riding accidents in terms of victim, task, product and environment. Prevention measures have been developed based on the major causes of accidents and other related contributing factors. The results from the analysis indicated that the majority of the escalator riding accidents was caused by passengers' carrying out other tasks (38 cases, including carrying luggage 24 cases, looking after accompany persons 9 cases, and 5 others), loss of balance (26 cases, 13.4%), not holding the handrail (20 cases, 10.3%), unhealthy passengers (18 cases, 9.3%), followed by people struck by other passenger (16 cases, 8.2%). For female passengers aged 15-64 years, their rushing for trains accidents could have been prevented by wearing safer footwear or by appropriate signing being provided indicating the location and traveling direction of escalators. Female passengers aged 65 years and above whose accidents were caused by loss of balance, should be encouraged to take the elevator instead. To prevent entrapment injuries, following a stricter design code can be most effective. Further in-depth accident investigation is suggested to cover the activity of the victim prior to the accident, any involved product, the location of the accident on the escalator, any medical treatment, what went wrong, opinion of the respondent on the causes of the accident, and personal characteristics of the passengers. Also, management must trade off productivity and safety appropriately to prevent "Organizational

Assessment of hemodynamic changes in patients with renal artery stenosis by means of the cine MR phase-contrast technique; Einstufung haemodynamischer Veraenderungen bei Nierenarterienstenosen mittels MR-Cine-Phasenkontrastflussmessungen

Energy Technology Data Exchange (ETDEWEB)

Schoenberg, S.O.; Knopp, M.V.; Bock, M.; Essig, M.; Hawighorst, H.; Zuna, I.; Schad, L.; Kaick, G. van [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Kallinowski, F.; Allenberg, J.R. [Chirurgische Universitaetsklinik, Heidelberg (Germany). Sektion Gefaesschirurgie; Just, A. [Heidelberg Univ. (Germany). 1. Physiologisches Inst.

1997-08-01

Purpose: To evaluate the use of high-temporal resolution cine MR phase-contrast flow measurements for assessment of flow dynamics in renal artery stenosis (RAS). Material and methods: In a dog model, cine MR flow measurements were validated by comparing the MR flow data to an invasive transit-time ultrasound reference technique for different degrees of RAS. Cardiac-gated MR flow curves were recorded in 56 renal arteries of 28 patients with a temporal resolution of at least 32 ms. In all cases RAS was confirmed by digital subtraction angiography (DSA). Abnormalities of flow dynamics were assessed in the calculated flow curves using the MR parameters mean flow, maximum velocity, and time to systolic maximum. Results: By means of the MR blood flow paremeters high-grade stenoses (>50%, n=23) were detected with sensitivity of 100% and specificity of 94% with reference to DSA. The overall differentiation between stenoses (n=37) and non-stenosed vessels (n=19) revealed a sensitivity of 87% and a specificity of 100%. Conclusion: Analysis of cardiac-gated MR flow curves provides a non-invasive method to assess the hemodynamic significance of RAS and thus allows a functional evaluation in relation to the morphologic characteristics of the stenosis. (orig.) [Deutsch] Ziel der Untersuchung war die Beurteilung der Haemodynamik bei Nierenarterienstenosen mittels Cine-MR-Phasenkontrastflussmessungen. In einem Hundemodell wurde die Cine-MR-Flussmessung validiert, indem fuer unterschiedliche Stenosegrade Vergleichsmessungen mit einer invasiven Transitzeit-Ultraschallreferenztechnik durchgefuehrt wurden. EKG-getriggerte MR-Flusskurven wurden bei 28 Patienten in 56 Nierenarterien mit einer Zeitaufloesung von mindestens 32 ms aufgenommen. Alle Nierenarterienstenosen wurden mittels digitaler Subtraktionsangiographie gesichert. Stoerungen in der renalen Haemodynamik wurden anhand der berechneten MR-Flusskurven mit Hilfe der Parameter `Mittelfluss, `maximale Geschwindigkeit` und `Zeit

Pretherapeutic and posttherapeutic laryngeal imaging; Prae- und posttherapeutische Larynxbildgebung

Energy Technology Data Exchange (ETDEWEB)

Becker, M.; Burkhardt, K.; Allal, A.S.; Dulguerov, P.; Ratib, O.; Becker, C.D. [Hopitaux Universitaires de Geneve, Abteilung fuer Hals-Nasen-Ohren-Radiologie, Geneve (Switzerland)

2009-01-15

endoskopischer Biopsie) beigeordnet und ergaenzen diese komplementaer. Eine sehr genaue Kenntnis der submukoesen Tumorausbreitungswege, der diagnostischen Zeichen der Tumorinfiltration und deren Konsequenzen fuer Stadieneinteilung und Therapie sind unentbehrlich fuer die Interpretation von CT-, MRT- und PET-CT-Bildern. Sowohl CT als auch MRT sind hochsensitive Untersuchungen zum Nachweis der neoplastischen Infiltration des praeepi- und paraglottischen Raums, der Subglottis und des Knorpels. Die Spezifitaet ist jedoch mit beiden Methoden weniger hoch als zunaechst erwartet, wodurch eine Tendenz zum Ueberschaetzen der Tumorausbreitung resultiert. Neuere Untersuchungen haben jedoch gezeigt, dass die Spezifitaet der MRT mittels Anwendung neuer diagnostischer Kriterien signifikant verbessert werden kann, da eine Unterscheidung zwischen Tumor und peritumoraler Entzuendung in vielen Faellen moeglich ist. Der sehr hohe negative Vorhersagewert der beiden Schnittbildverfahren ist aus klinischer Sicht wichtig, da er es ermoeglicht, die neoplastische Knorpelinfiltration auszuschliessen. Beide Methoden verbessern signifikant die praetherapeutische Stagingtreffsicherheit, wenn sie zusaetzlich zur Endoskopie eingesetzt werden. Bei submukoesen Tumoren liefern sowohl CT als auch MRT wertvolle Hinweise auf eine moegliche Aetiologie, auf das Ausmass des submukoesen Wachstums und die geeignete Biopsiestelle. Sie spielen auch eine wichtige Rolle bei der Diagnose von Laryngozelen, der Abklaerung von N.-laryngeus-recurrens-Paresen und Larynxfrakturen. (orig.)

Operation planning for a pondage power station chain by means of linear programming and genetic optimisation; Einsatzplanung fuer eine Flusskraftwerkskette im Schwellbetrieb mittels LP und genetischer Optimierung

Energy Technology Data Exchange (ETDEWEB)

Mueller, H.; Huelsemann, M.

1997-12-31

This paper presents a system package which serves as a simulation and optimisation tool for daily operation planning for a hydroelectric cascade. The purpose of the planning is to maximise (the differentially weighted) production of electrical energy given a certain set of specifications and secondary conditions. Optimal operation management is achieved using a two-stage approach: first pre-optimisation by means of linear programming, followed by detail optimisation using a Genetic Algorithm based on a non-linear, dynamic model of the power station and reservoir chain. [Deutsch] Im Beitrag wird ein Systempaket als Simulations- und Optimierungswerkzeug zur taeglichen Betriebsplanung einer Wasserkraftwerkskaskade vorgestellt. Ziel der Wasserbewirtschaftung ist es, unter den gegebenen Vorgaben und Randbedingungen die (bewertete) Erzeugung elektrischer Energie zu maximieren. Das optimale Fahrplanmanagement wird durch einen zweistufigen Loesungsansatz realisiert: Mit einer Vor-Optimierung mittels Linearer Programmierung (LP), gefolgt von einer detaillierten Optimierung mit einem Genetischen Algorithmus, der auf ein nichtlineares, dynamisches Simulationsmodell fuer die Kette aus Kraftwerken und Stauraeumen zugreift. (orig./RHM)

Radiological diagnosis of Klatskin's tumour; Radiologische Diagnostik von Klatskin-Tumoren

Energy Technology Data Exchange (ETDEWEB)

Pauls, S.; Juchems, M.S.; Brambs, H.-J. [Universitaetsklinikum Ulm (Germany). Abteilung Diagnostische Radiologie

2005-11-01

Patients with Klatskin's tumour present clinically unspecific symptoms such as painless jaundice and cholangitic discomfort. The only curative treatment is R0 resection of the tumour. To allow stage-specific therapy, accurate tumour staging is indispensable, the first step of which is abdominal sonography. If there is a suspect finding, cross-sectional imaging techniques like MRI or MDR-CT are used to clarify or stage the lesion, respectively. To estimate resectability, MRI together with MRC and MRI angiography are superior to MDR-CT. Biopsy using ERC is required before starting any specific treatment. If therapeutically relevant peritoneal carcinosis is clinically suspected although not radiologically confirmed, PET should also be performed. The value of PET/CT has to be evaluated in further studies. For optimal treatment, close cooperation between clinicians and radiologists is necessary. (orig.) [German] Patienten mit Klatskin-Tumoren werden klinisch durch unspezifische Symptome wie z. B. schmerzloser Ikterus oder cholangitische Beschwerden auffaellig. Eine R0-Resektion ist der einzige kurative Therapieansatz. Um eine stadiengerechte Therapie zu ermoeglichen, muss ein moeglichst exaktes Tumorstaging erfolgen. Primaer kommt die abdominelle Sonographie zum Einsatz. Zur Abklaerung eines unklaren Sonographiebefundes sowie zum Staging eines suspizierten Tumors werden Schnittbildverfahren MRT und MDR-CT benoetigt. Zur Beurteilung der lokalen Tumorresektabilitaet ist die MRT in Zusammenschau mit der MRC sowie MR-Angiographie der MDR-CT ueberlegen. Vor Einleitung einer Therapie sollte auf jeden Fall die Verdachtsdiagnose eines Klatskin-Tumors bioptisch mittels ERC gesichert werden. Wird klinisch trotz negativem Nachweis einer Peritonealkarzinose eine solche suspiziert, sollte bei Therapierelevanz (z. B. bei ansonsten fehlendem Nachweis einer Fernmetastasierung) eine PET ergaenzend durchgefuehrt werden. Der zukuenftige Stellenwert der PET/CT muss in weiteren Studien

Floating venous thrombi: diagnosis with spiral-CT-venography; Diagnose flottierender venoeser Thromben mittels Phlebo-Spiral-CT

Energy Technology Data Exchange (ETDEWEB)

Gartenschlaeger, M. [Mainz Univ. (Germany). Klinik fuer Radiologie; Klose, K.J. [Univ. Marburg, Medizinisches Zentrum fuer Innere Medizin, Abt. Poliklinik (Germany); Schmidt, J.A. [Univ. Marburg, Medizinisches Zentrum fuer Radiologie, Abt. fuer Strahlendiagnostik (Germany)

1996-05-01

Local application of contrast agent into an ipsilateral dorsal foot vein and spiral CT were used to examine 16 consecutive cases with deep venous thrombosis proven at conventional venography; in addition, colour Doppler flow imaging was performed. At conventional venography, 8/16 thrombi appeared to be floating and the remaining 8/16 were adherent to the vessel wall. Spiral-CT showed 15/16 thrombi to be adherent to the vessel wall; the floating thrombus correlated with findings in conventional venography. At colour Doppler flow imaging 3/16 thrombi were considered floating, one of them was discordant to conventional venography. The comparison of conventional venography to spiral-CT demonstrates complete agreement for adherence to vessel wall seen in conventional venography (p=1,0) and significant discordance in cases with free-floating appearance in conventional venography. Adherence of thrombi to the wall of the vessel at conventional venography is in agreement with computed tomography. Conventional venography probably overestimates the prevalence of free floating thrombi. (orig./MG) [Deutsch] Mittels lokaler Kontrastmittelapplikation in eine ipsilaterale Fussrueckenvene und Spiral-CT wurden 16 konsekutive Faelle konventionell phlebographisch gesicherter Phlebothrombose untersucht, zusaetzlich wurde die farbkodierte Doppler-Ultraschalluntersuchung durchgefuehrt. In der konventionellen Phlebographie waren 8/16 Thromben flottierend, die uebrigen 8/16 wandadhaerent. In der Spiral-CT zeigten sich Wandadhaerenzen in 15/16 Faellen; der nachgewiesene flottierende Thrombus stimmte mit der konventionellen Phlebographie ueberein. Im farbkodierten Doppler-Ultraschall erschienen die Thromben in 3/16 Faellen flottierend, darunter ein von der konventionellen Phlebographie abweichender Befund. Der Vergleich von konventioneller und CT-Phlebographie ergab eine komplette Uebereinstimmung fuer konventionell phlebographisch nachgewiesene Wandadhaerenz und eine signifikante Abweichung

Utility of coronal oblique slices in cervical spine MRI. Improved detection of the neuroforamina; Nutzen der halbkoronaren Schichtung im MRT der Halswirbelsaeule. Verbesserte Erkennbarkeit von Neuroforamina

Energy Technology Data Exchange (ETDEWEB)

Freund, W.; Hoepner, G. [Universitaetskliniken Ulm, Klinik fuer Diagnostische und Interventionelle Radiologie, Ulm (Germany); Klessinger, S. [Nova Clinic Biberach, Neurochirurgie, Biberach (Germany); Universitaetskliniken Ulm, Neurochirurgie, Ulm (Germany); Mueller, M. [Universitaetskliniken Ulm, Klinik fuer Diagnostische und Interventionelle Radiologie, Ulm (Germany); Universitaetskliniken Aachen, Diagnostische und Interventionelle Neuroradiologie, Aachen (Germany); Halatsch, M.E. [Universitaetskliniken Ulm, Neurochirurgie, Ulm (Germany); Weber, F. [Bundeswehrkrankenhaus Ulm, Neurologie, Ulm (Germany); Schmitz, B. [Universitaetskliniken Ulm, Neuroradiologie, Ulm (Germany)

2015-11-15

Angulated projections are standard in conventional radiography of the cervical spine, but rarely used in magnetic resonance imaging (MRI). As neuroforaminal pathology plays an important role in the etiology of radicular syndromes and may influence an operative approach, the utility of coronal oblique slices in MRI is explored. In a retrospective setting, 25 consecutive patients with neurologically diagnosed cervical monoradiculopathy were identified. T2-weighted sagittal, coronal oblique, and transversal slice orientations were anonymized. Two radiologists and two neurosurgeons independently assessed the cases. Criteria were site, cause, and grading of the neuroforaminal stenosis and the level of confidence on a 100-point visual analog scale (VAS). We computed interrater agreement, sensitivity, and t tests. Using only one slice orientation, the sensitivity in detecting the relevant neuroforamen was 0.40 for transversal, 0.68 for sagittal, and 0.64 for coronal oblique scans. A combination of the different angulations increased sensitivity and in 4 cases only the coronal oblique scans proved diagnostic. The readers felt significantly more confident in attributing the cause of the pathology on coronal oblique planes (a mean of 72 VAS points, p = 0.0003 vs 58 (sagittal) vs 64 (transversal)). Interrater agreement was significantly better for experienced (kappa 0. 48) than for inexperienced readers (0.32, p = 0.02). Adding coronal oblique planes in cervical spine MRI increases sensitivity and confidence in attributing the cause of neuroforaminal pathology. They are regarded as useful by all the readers. (orig.) [German] Im Gegensatz zur Magnetresonanztomographie (MRT) sind in der konventionellen Roentgendiagnostik der Halswirbelsaeule (HWS) Schraegaufnahmen Standard. Da neuroforaminale Pathologien wichtige Ursachen von radikulaeren Syndromen sind und die Operationstechnik moeglicherweise beeinflussen, wird der Nutzen halbkoronarer Schichten in der MRT untersucht. In

C-arm computed tomography for transarterial chemoperfusion and chemo-embolization of thoracic lesions; Transarterielle Chemoperfusion und -embolisation thorakaler Neoplasmen mittels C-Arm CT

Energy Technology Data Exchange (ETDEWEB)

Vogl, T.J.; Naguib, N.N.; Nour-Eldin, N.E.; Lehnert, T.; Mbalisike, E. [Klinikum der Johann-Wolfgang-Goethe-Universitaet, Institut fuer Diagnostische und Interventionelle Radiologie, Frankfurt am Main (Germany)

2009-09-15

To evaluate the role of C-arm CT for on-line fluoroscopy in regional transarterial chemoperfusion (TACP) and chemo-embolization (TPCE) of primary and secondary malignant thoracic lesions. From September 2008 to March 2009 a total of 31 patients (20 males and 11 females, average age: 61.7 years, range 22-84 years) with 53 thoracic malignant lesions from different origins (primary or secondary pulmonary carcinoma n=37, pleural mesothelioma n=16) were treated with TACP or TPCE using flat-detector CT (FD-CT). C-arm CT of the latest generation was used to localize the lesion before local chemotherapy (Artis Zeego, Siemens, Erlangen). For TACP a 220 rotation and a volume of 150 ml (ratio of 1:2 contrast/normal saline), delay 2 s and flow 12 ml/s was used. For TPCE a volume of 75 ml (ratio of 1:2 contrast/normal saline), delay 2 s and flow 3 ml/s was used. TPCE C-arm CT allowed the evaluation of the degree of perfusion of the tumor and the geographic areas of enhancement correlated with the post-interventional lipiodol uptake in MSCT. In TACP the intercostal arteries involved could be visualized and in 30% of interventions the catheter had to be repositioned for the following intervention. C-arm CT provides additional information on the vascular characteristics and perfusion of pulmonary lesions resulting in a change of interventional strategy in a relevant number of patients. (orig.) [German] Ziel der Arbeit war die Evaluation der Wertigkeit der C-Arm CT fuer die online gesteuerte regionale transarterielle Chemoperfusion (TACP) und die transpulmonale Chemoembolisation (TPCE) primaerer und sekundaerer thorakaler Neoplasmen Von September 2008 bis Maerz 2009 wurden 31 Patienten (11 Frauen/20 Maenner, Durchschnittsalter 61,7 Jahre) mit 53 unterschiedlichen thorakalen Neoplasmen (primaere oder sekundaere Lungenkarzinome [n=37], Pleuramesotheliome [n=16]) mittels TACP oder TPCE unter Einsatz der Flachdetektortechnologie (FD-CT) behandelt. Alle Behandlungen erfolgten an einem C

Precision of MR-guided needle placement. Experimental results; Praezision der Lokalisierbarkeit einer Punktionsnadel in der MRT. Experimentelle Ergebnisse

Energy Technology Data Exchange (ETDEWEB)

Langen, H.J. [Roentgenabteilung der Missionsaerztlichen Klinik Wuerzburg (Germany); Stuetzer, H. [Inst. fuer Medizinische Statistik, Informatik und Epidemiologie der Univ. zu Koeln (Germany); Kugel, H.; Krug, B.; Hesselmann, V.; Schulte, O.; Walter, C.; Landwehr, P. [Inst. und Poliklinik fuer Radiologische Diagnostik der Univ. zu Koeln (Germany)

2000-11-01

-Geraet mit Turbo-Spin-Echo (TSE)- und Gradienten-Echo (FFE)-Sequenzen von 20 s bzw. 40 s Dauer in 34 unterschiedlichen Orientierungen der Nadel zu B{sub 0} Frequenzkodier- und Schichtselektionsgradienten dargestellt. 4 in der Beurteilung von Nadelartefakten unerfahrene Untersucher schaetzten unabhaengig voneinander die Positionen der Nadelspitze anhand der Artefakte ab. Die Nadelpositionen wurden vor und nach einer 15minuetigen Einweisung bestimmt, in der anhand von hochaufloesenden MR-Bildern Groesse und Form der Artfakte erklaert wurden, die bei den 12 moeglichen Kombinationen von parallelen oder rechtwinkligen Anordnungen der Nadeln zu B{sub 0} und zum Frequenzkodiergradienten auftreten. Die vor und nach der Einweisung bestimmten Positionen wurden mit den tatsaechlichen Nadelpositionen verglichen. Ergebnisse: Die Laenge der Nadel wurde in den TSE-Bildem im Mittel um 1,8{+-}2,3 mm, in den FFE-Bildern um 2,5{+-}1,2 mm ueberschaetzt. Nach der Uebung nahm der Fehler signifikant auf 0,2{+-}1,8 mm fuer die TSE-Bilder und auf 1,0{+-}1,8 mm fuer die FFE-Bilder ab. Die Lokalisation der Nadelspitze gelang in den TSE-Sequenzen im Mittel mit einer hoeheren Praezision. Schlussfolgerung: Bei MR-gesteuerter Biopsie unter Verwendung von FFE- und TSE-Sequenzen kann die Nadelposition praeziser bestimmt werden, wenn der Untersucher mit den Artefaktformen vertraut ist, die bei den 12 moeglichen rechtwinkligen oder parallelen Orientierungen der Nadel zu B{sub 0} und Frequenzkodiergradienten entstehen. (orig.)

Influence of platform screen doors on energy consumption of the environment control system of a mass rapid transit system: case study of the Taipei MRT system

Energy Technology Data Exchange (ETDEWEB)

Hu, S.-C. E-mail: f10870@ntut.edu.tw; Lee, J.-H

2004-03-01

This investigation studies how platform screen doors (PSD) affect the energy consumption of the environmental control system of a mass rapid transit (MRT) system in Taipei. The environmental parameter simulation was conducted using the subway environmental simulation (SES) program, while the associated air conditioning (A/C) cooling load was predicted with the carrier E20-II program. Results show that PSD can significantly decrease average and peak cooling load, thus reducing the capacity/size of cooling equipment and allowing the chiller cooling load to be abridged. However, electricity consumption by ventilation equipment increases notably when PSD are used, particularly the electricity consumption by the under platform exhaust (UPE) fan, and thus, ultimately, little difference exists in the overall energy consumption with and without UPE.

Influence of platform screen doors on energy consumption of the environment control system of a mass rapid transit system: case study of the Taipei MRT system

International Nuclear Information System (INIS)

Hu, S.-C.; Lee, J.-H.

2004-01-01

This investigation studies how platform screen doors (PSD) affect the energy consumption of the environmental control system of a mass rapid transit (MRT) system in Taipei. The environmental parameter simulation was conducted using the subway environmental simulation (SES) program, while the associated air conditioning (A/C) cooling load was predicted with the carrier E20-II program. Results show that PSD can significantly decrease average and peak cooling load, thus reducing the capacity/size of cooling equipment and allowing the chiller cooling load to be abridged. However, electricity consumption by ventilation equipment increases notably when PSD are used, particularly the electricity consumption by the under platform exhaust (UPE) fan, and thus, ultimately, little difference exists in the overall energy consumption with and without UPE

Selected clinically established and scientific techniques of diffusion-weighted MRI. In the context of imaging in oncology; Ausgewaehlte klinisch etablierte und wissenschaftliche Techniken der diffusionsgewichteten MRT. Im Kontext der onkologischen Bildgebung

Energy Technology Data Exchange (ETDEWEB)

Freitag, M.T.; Bickelhaupt, S.; Ziener, C.; Mosebach, J.; Schlemmer, H.P. [Deutsches Krebsforschungszentrum, Abteilung fuer Radiologie, Heidelberg (Germany); Meier-Hein, K. [Deutsches Krebsforschungszentrum, Abteilung fuer medizinische Informatik, Heidelberg (Germany); Radtke, J.P. [Deutsches Krebsforschungszentrum, Abteilung fuer Radiologie, Heidelberg (Germany); Universitaetsklinik Heidelberg, Abteilung fuer Urologie, Heidelberg (Germany); Kuder, T.A.; Laun, F.B. [Deutsches Krebsforschungszentrum, Abteilung fuer Medizinische Physik in der Radiologie, Heidelberg (Germany)

2016-02-15

Diffusion-weighted imaging (DWI) is a magnetic resonance imaging (MRI) technique that was established in the clinical routine primarily for the detection of brain ischemia. In the past 15 years its clinical use has been extended to oncological radiology, as tumor and metastases can be depicted in DWI due to their hypercellular nature. The basis of DWI is the Stejskal-Tanner experiment. The diffusion properties of tissue can be visualized after acquisition of at least two diffusion-weighted series using echo planar imaging and a specific sequence of gradient pulses. The use of DWI in prostate MRI was reported to be one of the first established applications that found its way into internationally recognized clinical guidelines of the European Society of Urological Radiology (ESUR) and the prostate imaging reporting and data system (PI-RADS) scale. Due to recently reported high specificity and negative predictive values of 94 % and 92 %, respectively, its regular use for breast MRI is expected in the near future. Furthermore, DWI can also reliably be used for whole-body imaging in patients with multiple myeloma or for measuring the extent of bone metastases. New techniques in DWI, such as intravoxel incoherent motion imaging, diffusion kurtosis imaging and histogram-based analyses represent promising approaches to achieve a more quantitative evaluation for tumor detection and therapy response. (orig.) [German] Die diffusionsgewichtete Bildgebung (''diffusion-weighted imaging'', DWI), ein Verfahren aus der Magnetresonanztomographie (MRT), wurde in der klinischen Routine primaer fuer die Detektion von Schlaganfaellen etabliert. Der Einsatz dieser Methode hat in den letzten 15 Jahren auch fuer die onkologische Diagnostik stark zugenommen, da Tumoren und Metastasen aufgrund ihrer hochzellulaeren Zusammensetzung in der DWI sehr gut sichtbar gemacht werden koennen. Basis der diffusionsgewichteten Bildgebung ist das Experiment nach Stejskal-Tanner. Hier

Functional magnetic resonance imaging in neuroradiology; Funktionelle Magnetresonanztomographie in der Neuroradiologie

Energy Technology Data Exchange (ETDEWEB)

Essig, M.; Schoenberg, S.O.; Schlemmer, H.P.; Metzner, R.; Kaick, G. van [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie

2000-10-01

Bildgebungssequenzen, optimierter Kontrastmittelapplikationen und spezieller Nachverarbeitungsmethoden wurde es moeglich, physiologische und pathophysiologische Prozesse mittels der Magnetresonanztomographie (MRT) zu beobachten. Mit T1- und T2*-gewichteten kontrastmittelunterstuetzten Bildgebungssequenzen koennen Informationen ueber die Gewebeperfusion, Mikrozirkulation und die Permeabilitaet der Blut-Hirn-Schranke unter Anwendung spezieller, z.T. aus der Nuklearmedizin stammender Modelle erfasst werden. Die Eigendiffusion von Wassermolekuelen im Gewebe ist mit diffusiongewichteter MRT, die Markrovaskulatur, zeitlich aufgeloest, mit MR-angiographischen Techniken darstellbar. Auch eine neuronale Aktivitaet einfacher oder komplexer Natur kann mit funktionellen MR-Techniken visualisiert werden. Mit MR-spektroskopischen Untersuchungen koennen metabolische Verteilungen in normalem und pathologischem Gewebe mehrdimensional erfasst und Stoffwechselvorgaenge im Verlauf beobachtet werden. Vorteile der MRT ist die geringe Invasivitaet, die Moeglichkeit einer dreidimensionalen Darstellung der Daten und eine beliebige Wiederholbarkeit der Untersuchung bei fehlender Strahlenbelastung. Die bereits klinisch einsetzbaren funktionellen Methoden werden beschrieben und ihr Einsatz in der Neuroradiologie auch in Bezug auf die Wertigkeit im Vergleich zu nuklearmedizinischen Methoden diskutiert. Perfusions- und Diffusions-MRT liefern wichtige Zusatzinformationen im akuten und chronischen Stadium der zerebralen Ischaemie und werden bereits routinemaessig bei akutem Schlaganfall eingesetzt. Dynamische MR-Angiographien erlauben eine haemodynamische Einstufung von Gefaessmissbildungen. In der Tumordiagnostik liefern die funktionellen MR-Techniken wichtige Zusatzinformationen fuer die Therapiefindung, Therapieplanung und das Therapiemonitoring. Die Untersuchung psychiatrischen Erkrankungen wurden durch die funktionelle MRT revolutioniert, obwohl der klinische Einsatz noch limitiert ist. Erste Untersuchungen

Diagnostik und Therapie der kutanen Androgenisierung im klimakterischen Übergang sowie in der Peri- und Postmenopause: Hirsutismus und Alopezie

Directory of Open Access Journals (Sweden)

Geisthövel F

2012-01-01

Full Text Available Die weibliche Androgenisierung umfasst ein weites Spektrum an heterogenen Dysfunktionen und Erkrankungen. Um die Therapieprinzipien des Hirsutismus sowie der Alopecia androgenetica während des klimakterischen Übergangs („menopausal transition“ [MT] und der Peri-/Postmenopause zu erfassen, ist es sinnvoll, sich auf eine Gruppe von androgenisierten Patientinnen zu beschränken, bei der die Haut pathogenetisch im Fokus liegt. Solch eine klar definierte Patientengruppe, die „funktionell kutane Androgenisierung“ (FCA, kann meist schon über die Diagnostikebene 1 (Screening-Ebene unseres Klassifikations-Algorithmus diagnostiziert werden. Der Ferriman-Gallwey-Index bzw. eine modifizierte Sinclair-Scale dienen zur Gradeinteilung von Hirsutismus bzw. Alopezie. Die ausgeprägte endokrine Dynamik während der MT ist hormondiagnostisch zu beachten. Wachsepilation und Lasertherapie sind vielfältig eingesetzte topischmechanische bzw. -physikalische Therapieverfahren. Eine topische Behandlung des Hirsutismus kann auch mit Eflornithin-Creme durchgeführt werden, die den Effekt einer Lasertherapie unterstützt. Minoxidil-Lösung gilt als Mittel der ersten Wahl bei der topischen Therapie der Alopecia androgenetica. Steroidale Präparate, welche aus der kontrazeptiven Kombination von Ethinylestradiol und antiandrogenen Gestagenen (AA bestehen, sind therapeutische Prinzipien bei androgenisierten Patientinnen in der MT, sie sind hingegen in der Postmenopause kontraindiziert. Die orale Einnahme von Spironolacton und/oder Finasterid, beides nicht-steroidale Antiandrogene, ist während der MT unter sicherer Kontrazeption und jene von Spironolacton für die Alopezie in der Postmenopause gut geeignet. Die Einnahme von Kombinationsprapäraten, welche die nicht-kontrazeptiven natürlichen Östrogene und AA enthalten, sind für die Behandlung der FCA bei Patientinnen indiziert, die zusätzlich unter klimakterischen und peri-/postmenopausalen Störungen leiden

Functional magnetic resonance imaging in the activation of working memory; Funktionelle Magnetresonanztomographie bei Aktivierung des Arbeitsgedaechtnisses

Energy Technology Data Exchange (ETDEWEB)

Spitzer, M. [Sektion Experimentelle Psychopathologie, Psychiatrische Universitaetsklinik, Heidelberg (Germany); Kammer, T. [Sektion Experimentelle Psychopathologie, Psychiatrische Universitaetsklinik, Heidelberg (Germany); Bellemann, M.E. [Forschungsschwerpunkt Radiologische Diagnostik und Therapie, Deutsches Krebsforschungszentrum, Heidelberg (Germany); Gueckel, F. [Inst. fuer Klinische Radiologie, Klinische Fakultaet 2, Univ. Heidelberg, Klinikum Mannheim (Germany); Georgi, M. [Inst. fuer Klinische Radiologie, Klinische Fakultaet 2, Univ. Heidelberg, Klinikum Mannheim (Germany); Gass, A. [Neurologische Klinik, Klinische Fakultaet 2, Univ. Heidelberg, Klinikum Mannheim (Germany); Brix, G. [Forschungsschwerpunkt Radiologische Diagnostik und Therapie, Deutsches Krebsforschungszentrum, Heidelberg (Germany)

1996-07-01

Functional magnetic resonance imaging was used in conjunction with a letter detection task for the study of working memory in 16 normal subjects. Because of movement artifacts, data from only 9 subjects were analysed. In the activation taks, subjects responded by pressing a button whenever any presented letter was the same as the second last in the sequence. In the control condition, the subjects had to respond to a fixed letter. Hence, the activation condition and the control condition differend only subjectively, i.e., regarding the task demand, whereas the stimuli and the type and frequency of response were identical. The activation condition produced significant activation in the dorsolateral prefrontal cortex (Brodmann`s areas 10, 46, and 9). In contrast to experimental tasks previsouly used rather extensively to study the prefrontal cortex, the present paradigm is characterized by its simplicity, interpretability, and its ties to known neurophysiology of the frontal cortex. (orig.) [Deutsch] Unter Verwendung eines Buchstabenerkennungsparadigmas wurde die Funktion des Arbeitsgedaechtnisses mittels funktioneller Magnetresonanztomographie an 16 gesunden Probanden untersucht, von denen 9 ausgewertet werden konnten. Aktivierungsbedingung (Reaktion auf jeden Buchstaben, der identisch ist mit dem jeweils vorletzten Buchstaben) und Kontrollbedingung (Reaktion auf einen bestimmten vorselektierten Buchstaben) unterschieden sich lediglich durch unterschiedliche Instruktionen. Die beiden Bedingungen waren damit subjektiv verschieden, jedoch durch physikalisch identische Reize sowie eine identische Reaktion (Erkennen des zu diskriminierenden Zielreizes und Knopfdruck) charakterisiert. Unter der das Arbeitsgedaechtnis beanspruchenden Aktivierungsbedingung wurde eine umschriebene signifikante Vermehrung der Aktivtaet im dorsolateralen praefrontalen Kortex (Brodmannsche Areale 10, 46 und 9) beobachtet. Im Gegensatz zu anderen experimentellen Paradigmen, die zu funktionellen

Frauen. Kultur. Mittel- und Osteuropa oder: Über den langsamen Einzug der gender studies in die slawistischen Kulturwissenschaften Women. Culture. Middle and Eastern Europe or: On the Slow Introduction of gender studies into the Slavonic Cultural Sciences

Directory of Open Access Journals (Sweden)

Barbara Wurm

2001-03-01

Full Text Available Der vorliegende Sammelband, entstanden anläßlich einer Konferenz, die im September 1997 vom Institut für Slawistik der Universität Innsbruck in Zusammenarbeit mit der österreichischen UNESCO-Kommission veranstaltet wurde, untersucht aus soziologischer, kulturhistorischer, literatur- und filmwissenschaftlicher Perspektive verschiedenste Aspekte der Institutionalisierung und Repräsentation von „Frauen in der Kultur“ Mittel- und Osteuropas.This anthology, the result of a conference organized in September 1997 by the Institute for Slavonic studies at the University of Innsbruck in co-operation with the Austrian UNESCO commission, examines various aspects of the institutionalization and representation of women in Middle and Eastern European culture from a sociological and cultural historical perspective and from that of literary and film sciences.

Therapy by electromagnetic wave of millimeter energy range (EFH-therapy, MRT, IWT). Scientific and practical materials on the use of physical factors in clinical and health resort practice

International Nuclear Information System (INIS)

Samosyuk, I.Z.; Fisenko, L.I.; Kolesnik, K.Eh.; Chukhraev, N.V.; Shimkov, G.E.

1998-01-01

Problems of extremely high frequency (EHF) therapy, microwave resonance therapy (MRT) and information-wave therapy (IWT) are considered. Possibilities of electromagnetic waves in millimeter energy range use in clinical and health resort practice are systematized. Recommendations on their use in treatment of different diseases are given. The main principles of selection of zones for meridian correction with the help of electromagnetic waves in millimeter energy range are exposed. The results of EFH-therapy clinical use indicate the possibility of its application practically in all cases, since positive results were obtained in most cases. The recommendations are prepared with account of possibilities and parameters of the apparatus ''MIT-1'' for reflexotherapy which was designed and produced by the Medical Innovative Centre in Kiev

Diagnostic imaging of Klippel-Feil syndrome: conventional radiography, CT and MR imaging. Case report; Bildgebende Diagnostik des Klippel-Feil-Syndroms: Konventionelle Roentgenaufnahmen, CT und MRT. Fallbericht

Energy Technology Data Exchange (ETDEWEB)

Jochens, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Schubeus, P. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Steinkamp, H.J. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Menzhausen, L. [Abt. fuer Psychiatrie, Urban Krankenhaus, Berlin (Germany); Felix, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany)

1993-12-31

In two patients with Klippel-Feil syndrome, type II radiographic findings of the malformation are shown in the cervical spine and the craniocervical junction. Conventional X-rays of the cervical spine in the AP and lateral view and conventional tomography as well as CT of the cervical spine were obtained in both patients. One of the two patients additionally underwent MR imaging. Findings of the different imaging modalities are compared with each other. (orig.) [Deutsch] Anhand von zwei Patienten mit Klippel-Feil-Syndrom Typ II werden typische radiologische Befunde des Missbildungssyndroms im Bereich der Halswirbelsaeule und des kraniozervikalen Ueberganges dargestellt. Neben den konventionellen HWS-Roentgenaufnahmen und den konventionellen Schichtaufnahmen, wurden bei beiden Patienten ein CT der HWS und bei einem Patienten zusaetzlich ein MRT durchgefuehrt. Die Ergebnisse und Befunde der verschiedenen Untersuchungsverfahren werden einander gegenuebergestellt. (orig.)

"Fordi man ved aldrig"

DEFF Research Database (Denmark)

Borchmann, Simon Uffe

2015-01-01

I denne artikel vil syntagmet aktivitetsbestemt sprogbrug blive udlagt fra en pragmatisk, funktionel lingvistisk synsvinkel. Syntagmet er særligt interessant fra denne synsvinkel fordi det synes at indebære et nyt sprogvidenskabeligt forskningsområde. Det er i det mindste det der vil blive argume...

Differential diagnostics of the musculoskeletal system in sports medicine; Differenzialdiagnostische Untersuchung in der Sportmedizin des Bewegungsapparats

Energy Technology Data Exchange (ETDEWEB)

Nehrer, S. [Donau-Universitaet Krems, Department fuer Klinische Medizin und Biotechnologie, Zentrum fuer Regenerative Medizin, Krems (Austria)

2010-05-15

sowie die Untersuchung unter Einschluss funktioneller Tests stehen wie immer am Anfang der diagnostischen Strategie; wobei der Verletzungsmechanismus und das sportspezifische Belastungsmuster beruecksichtigt werden muessen. Regionale Inspektions-, Palpations- und Testbefunde der verletzten Struktur weisen auf eine Verdachtsdiagnose hin, die durch bildgebende Verfahren bestaetigt oder auch widerlegt werden kann. Durch den effizienten Einsatz bildgebender Methoden kann dann rasch die entsprechende Therapie eingeleitet werden. Die Sonographie gibt hier, aufgrund ihrer raschen Verfuegbarkeit, vor allem im Bereich von Muskeln, Sehnen und Baendern u. U. wertvolle Hinweise. Die nativradiologische Abklaerung im Bereich des Knochens muss oft durch Zielaufnahmen ergaenzt werden. Die MRT stellt im Bereich der Gelenkverletzungen den Goldstandard dar, wobei eine exakte differenzialdiagnostische Fragestellung hilfreich ist, das Untersuchungsprotokoll entsprechend durchzufuehren, um die fraglich pathologischen Strukturen moeglichst klar darzustellen. (orig.)

Reduction of radiation dose by using digital luminescence radiography compared to conventional screen film system with grid cassette; Reduktion der Strahlendosis mittels Speicherfolienradiographie im Vergleich zum konventionellen Film-Folien-System mit Rasterkassette am Schaedelphantom

Energy Technology Data Exchange (ETDEWEB)

Heyne, J.P.; Merbold, H.; Neumann, R.; Freesmeyer, M.; Jonetz-Mentzel, L.; Kaiser, W.A. [Friedrich-Schiller-Univ. Jena, Inst. fuer Diagnostische und Interventionelle Radiologie (Germany); Sehner, J. [AGFA-Deutschland, Vertriebsgesellschaft (Germany)

1999-07-01

mittels RK und digital (ADC-70, Agfa) a.p. geroentgt. Bei konstanter Spannung wurde das mAs-Produkt stufenweise gesenkt und dabei die Eintrittsdosis mittels Halbleiterdetektor des Dosimax (Wellhoefer) ermittelt. 5 Untersucher beurteilten die Aufnahmen nach charakteristischen Bildmerkmalen, kritischen Strukturen, Ortsaufloesung und Bildkontrast. Ergebnisse: Die Eintrittsdosis betrug bei 73 kV/22 mAs konventionell (Rasterkassette) 0,432 mGy und digital 0,435 mGy. Bis zu einer durchschnittlichen Dosis von 71% (0,308 mGy; SD 0,050) waren die Aufnahmen sehr gut und bis zu einer durchschnittlichen Dosis von 31% (0,136 mGy; SD 0,065) ausreichend beurteilbar. Die erkennbaren Linienpaare/mm auf dem Bleistrichraster reduzierten sich dabei untersucherabhaengig bis zu 2 Stufen. Der Bildkontrast war sehr gut bis ausreichend. Die Akzeptanz der nachverarbeiteten Aufnahmen war individuell verschieden und erbrachte nur in hoeheren Dosisbereichen eine verbesserte Beurteilbarkeit der Knochenstrukturen und des Kontrastes. Schlussfolgerung: Fuer die ausreichende Beurteilbarkeit einer moeglichen Fraktur/der Nasennebenhoehlen/zur Vermessung kann die Dosis auf mindestens 56% (Durchmesser 31%; SD 14,9%)/40% (Durchmesser 27%; SD 9,3%)/18% (Durchmesser 14%; SD 4,4%) gesenkt werden. Mittels digitaler Radiografie wird damit bei 73 kV ein fragestellungsbezogenes mAs-Produkt moeglich und angegeben, so z.B. zum Frakturausschluss 73 kV/12,5 mAs und zur Schaedelvermessung 73 kV/4 mAs. (orig.)

Influence of platform screen doors on energy consumption of the environment control system of a mass rapid transit system: case study of the Taipei MRT [mass rapid transit] system

Energy Technology Data Exchange (ETDEWEB)

Shih-Cheng Hu; Jen-Ho Lee [National Taipei University of Technology, Taipei (China). Dept. of Air Conditioning and Refrigeration Engineering

2004-03-01

This investigation studies how platform screen doors (PSD) affect the energy consumption of the environmental control system of a mass rapid transit (MRT) system in Taipei. The environmental parameter simulation was conducted using the subway environmental simulation (SES) program, while the associated air conditioning (A/C) cooling load was predicted with the carrier E20-II program. Results show that PSD can significantly decrease average and peak cooling load, thus reducing the capacity/size of cooling equipment and allowing the chiller cooling load to be abridged. However, electricity consumption by ventilation equipment increases notably when PSD are used, particularly the electricity consumption by the under platform exhaust (UPE) fan, and thus, ultimately, little difference exists in the overall energy consumption with and without UPE. (author)

MR spectroscopy in dementia; MR-Spektroskopie bei Demenz

Energy Technology Data Exchange (ETDEWEB)

Hauser, T.; Gerigk, L.; Giesel, F.; Schuster, L.; Essig, M. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung E010, Radiologie, Heidelberg (Germany)

2010-09-15

With an increasingly aging population we are faced with the problem of an increasing number of dementia patients. In addition to clinical, neuropsychological and laboratory procedures, MRI plays an important role in the early diagnosis of dementia. In addition to various morphological changes functional changes can also help in the diagnosis and differential diagnosis of dementia. Overall the diagnosis of dementia can be improved by using parameters from MR spectroscopy. This article focuses on MR spectroscopic changes in the physiological aging process as well as on changes in mild cognitive impairment a precursor of Alzheimer's dementia, in Alzheimer's dementia, frontotemporal dementia, vascular dementia and Lewy body dementia. (orig.) [German] Angesichts einer immer aelter werdenden Bevoelkerung sind wir mit dem Problem einer zunehmenden Zahl an Demenzerkrankungen konfrontiert. Neben klinischen, neuropsychologischen und laborchemischen Verfahren spielt die MRT zur Fruehdiagnostik einer Demenz eine wichtige Rolle. Morphologische Veraenderungen wie auch verschiedene funktionelle Verfahren helfen bei der Diagnostik und Differenzialdiagnostik einer Demenz. Insgesamt kann mittels MR-spektroskopischer Parameter die Diagnostik einer Demenz verbessert werden. In diesem Artikel soll auf MR-spektroskopische Veraenderungen im Rahmen des physiologischen Alterungsprozesses eingegangen werden. Ferner werden speziell Veraenderungen bei leichter kognitiver Beeintraechtigung, einer Vorform der Alzheimer-Demenz, bei Alzheimer-, frontotemporaler, vaskulaerer und Lewy-Koerper-Demenz eroertert. (orig.)

Experimental determination of the electronic properties of application-relevant interfaces of organic semiconductors by means of photoelectron spectroscopy; Experimentelle Bestimmung der elektronischen Eigenschaften anwendungsrelevanter Grenzflaechen organischer Halbleiter mittels Photoelektronenspektroskopie

Energy Technology Data Exchange (ETDEWEB)

Grobosch, Mandy

2009-07-01

This thesis under the titel Experimental Determination of the Electronic Properties of Application-relevant Interfaces of Organic Semiconductors by means of Photoelectron Spectroscopy was drawn up at the Leibniz Institute for Solid-State and Materials Research (IFW) Dresden at the Institute for Solid-State Research (IFF) under the maintenance of Prof. Dr. B. Buechner. To the scientific study hereby came two types of application-relevant interfaces. On the one hand the influence of the electrode preparation under normal conditions by means of ex-situ purification procedures in comparison to in-situ prepared contacts on the electronic behaviour of the organic semiconductor sexithiophene on interfaces to metallic substrates was studied. As substrate materials hereby the metals silver, palladium, gold, and platinum came to application. In a second study the interfaces of the organic semiconductors sexithiophene and copper(II)-phthalocyanine in contact to thin films of the transition-metal oxide La{sub 0.7}Sr{sub 0.3}MnO{sub 3} were studied. Also here a comparing study for ex-situ and in-situ purificated La{sub 0.7}Sr{sub 0.3}MnO{sub 3} contacts was performed. The films applied for this were fabricated in the IWF Dresden at the Institute for Metallic Materials (IMW). Also in the framework of these studies the influence of oxygen on the electronic and chemical behaviour on the interfaces held the spotlight. [German] Diese Dissertation unter dem Titel Experimentelle Bestimmung der elektronischen Eigenschaften anwendungsrelevanter Grenzflaechen organischer Halbleiter mittels Photoelektronenspektroskopie wurde am Leibniz Institut fuer Festkoerper- und Werkstoffforschung (IFW) Dresden am Institut fuer Festkoerperforschung (IFF) unter der Betreuung von Prof. Dr. B. Buechner angefertigt. Zur wissenschaftlichen Untersuchung kamen hierbei zwei Typen anwendungsrelevanter Grenzflaechen. Zum einem wurde der Einfluss einer Elektrodenpraeparation unter Normalbedingungen mittels ex

Characterization of adrenal masses: can image replace biopsy?; Charakterisierung von Nebennierenraumforderungen. Kann die Bildgebung die Biopsie ersetzen?

Energy Technology Data Exchange (ETDEWEB)

Heinz-Peer, G.; Hoenigschnabel, S.; Lechner, G. [Universtaetsklinik fuer Radiodiagnostik, Abt. Chirurgische Faecher, Wien (Austria)]|[Ludwig Boltzmann-Inst. fuer Radiologische Tumorforschung, Wien (Austria); Niederle, B. [Universitaetsklinik fuer Chirurgie, Univ. Wien (Austria)

1999-07-01

This paper describes the diagnostic value of new imaging techniques in characterization of adrenal masses and evaluates the role of adrenal biopsy. For differentiation of benign and malignant adrenal lesions, sensitivities and specificities of 85-100% can be reached by unenhanced computed tomography (CT) methods, chemical shift techniques in magnetic resonance imaging (MRI), delayed enhanced CT techniques, and by evaluation of wash-out curves in contrast-enhanced CT. The diagnostic value of all CT techniques depends on threshold values. The value of dynamic contrast-enhanced MRI is under discussion and should be reevaluated by using delayed enhance series. Biochemical and scintigraphic methods (NP 59 iodine iodomethyl-norcholesterol and MIBG meta-iodobenzylguanidine scintigrams) are valuable for the diagnosis of functional adrenal masses; however, they do not allow differentiation of benign and malignant tumors. According to excellent results of new imaging techniques in characterization of adrenal masses, the indications for fine-needle aspiration biopsy have already regressed, as have complications associated with this invasive technique. (orig.) [Deutsch] Diese Arbeit beschreibt die Moeglichkeiten der Charakterisierung von Nebennierenlaesionen durch die Bildgebung von neuen Untersuchungstechniken und evaluiert den geaenderten Stellenwert der Nebennierenbiopsie. Mittels der nativen Computertomographie (CT), der Chemical-Shift-Technik der Magnetresonanztomographie (MRT) oder Dichtemessungen in CT-Kontrastmittelspaetserien bzw. der Bestimmung des prozentuellen Dichteverlustes in CT-Kontrastmittelserien koennen in der Differenzierung von benignen und malignen Nebennierenlaesionen Sensitivitaeten und Spezifitaeten von 85%-100% erreicht werden. Die diagnostische Wertigkeit der CT-Techniken ist abhaengig von der Definition eines Schwellenwertes. Die Wertigkeit der dynamischen KM-verstaerkten MRT wird derzeit unterschiedlich beurteilt und sollte anhand verbesserter

Functional MRI 2.0. {sup 23}Na and CEST imaging; Funktionelle MRT 2.0. {sup 23}Na- und CEST-Bildgebung

Energy Technology Data Exchange (ETDEWEB)

Haneder, S. [Uniklinik Koeln, Institut fuer Diagnostische und Interventionelle Radiologie, Koeln (Germany); Konstandin, S. [Universitaet Bremen, MR-Bildgebung und -Spektroskopie, Fachbereich 1 (Physik/Elektrotechnik), Bremen (Germany); Fraunhofer MEVIS, Institut fuer Bildgestuetzte Medizin, Bremen (Germany)

2016-02-15

In recent years the purely morphological magnetic resonance imaging (MRI) has been increasingly flanked by so-called functional imaging methods, such as diffusion-weighted imaging (DWI), to obtain additional information about tissue or pathological processes. This review article presents two MR techniques that can detect physiological processes in the human body. In contrast to all other functional MR imaging techniques, which are based on hydrogen protons, the first technique presented (X-nuclei imaging) uses the spin of other nuclei for imaging and consequently allows a completely different insight into the human body. In this article X-nuclei imaging is focused on sodium ({sup 23}Na) MRI because it currently represents the main focus of research in this field due to the favorable MR properties of sodium. The second MR technique presented is the relatively novel chemical exchange saturation transfer (CEST) imaging that can detect exchange processes between protons in metabolites and protons in free water. The first part of this article introduces the basic technical principles, problems, advantages and disadvantages of these two MR techniques, whereas the second part highlights the potential clinical applications. Examples illustrate several potential applications in neuroimaging (e. g. stroke and tumors), musculoskeletal imaging (e. g. osteoarthritis and degenerative processes) and abdominal imaging (e. g. kidneys and hypertension). Both techniques inherently contain an incredible potential for future imaging but are still on the threshold of clinical use and are currently under evaluation in many university centers. (orig.) [German] In den letzten Jahren wird die reine morphologische Magnetresonanztomographie (MRT) zunehmend von sogenannten funktionellen Bildgebungsmethoden, wie der diffusionsgewichteten Bildgebung (''diffusion-weighted imaging'', DWI), flankiert, um zusaetzliche Informationen ueber Gewebe oder pathologische Prozesse zu

Gaucher disease: MR evaluation of bone marrow features during treatment with enzyme replacement; Morbus Gaucher: Analyse der Knochenmarkveraenderungen in der MRT waehrend Enzymersatztherapie

Energy Technology Data Exchange (ETDEWEB)

Poll, L.W.; Koch, J.A.; Boerner, D.; Cohnen, M.; Jung, G.; Scherer, A.; Moedder, U. [Duesseldorf Univ. (DF). Inst. fuer Diagnostische Radiologie; Dahl, S. vom; Haeussinger, D. [Duesseldorf Univ. (Germany). Klinik fuer Gastroenterologie, Hepatologie und Infektiologie; Willers, R. [Rechenzentrum, Heinrich-Heine-Univ. Duesseldorf (Germany); Niederau, C. [Innere Abt., St. Josef-Hospital Oberhausen, Akademisches Lehrkrankenhaus der Univ. Essen (Germany)

2001-10-01

Purpose: Enzyme replacement therapy (ERT) arrests and reverses the hematological and visceral symptoms of adult Gaucher disease, the most frequent lysosomal storage disorder. There are only a few studies available evaluating bone disease during ERT. The aim of this study was to investigate the features of bone marrow (bm) by magnetic resonance imaging (MRI) in these patients during ERT. Materials and Methods: MRI was performed prospectively in thirty adult type I Gaucher patients before and during ERT with a mean follow-up of 3 years. Spin-echo sequences (T{sub 1}/T{sub 2}) of the lower extremities were obtained and the reconversion (response) or lack of reconversion (non-response) to fatty marrow during treatment was analyzed. The morphological features of bm involvement, a homogeneous or non-homogeneous distribution of bm changes and focal bone lesions surrounded by a rim of reduced signal intensity (SI), were analyzed. Results: Infiltration of bm by Gaucher cells is characterized by a reduction of Sl on both T{sub 1}- and T{sub 2}-weighted sequences. Bone marrow responses were seen in 19 patients (63%) during treatment. Focal bone lesions, surrounded by a rim of reduced Sl, did not respond to ERT and correlated with a non-homogenous distribution of bone involvement and splenectomy. (orig.) [German] Ziel: Unter Enzymersatztherapie (enzyme replacement therapy = ERT) zeigen Patienten mit adulter Form des Morbus Gaucher, der haeufigsten lysosomalen Speicherkrankheit, eine deutliche Besserung der haematologischen und visceralen Symptome. Bislang liegen nur wenige Untersuchungen zur Analyse der Knochenveraenderungen waehrend der ERT vor. Ziel war es, die Knochenmarkveraenderungen bei Gaucher-Patienten waehrend der Enzymersatztherapie mit Alglucerase/Imiglucerase in der Magnetresonanztomographie (MRT) zu evaluieren. Material und Methoden: In einer prospektiven Untersuchung wurden 30 adulte Patienten mit gesichertem Morbus Gaucher vor und waehrend der ERT in der MRT

Systematics of glenohumoral and acromioclavicular arthritis; Systematik der glenohumeralen und akromioklavikulaeren Arthrose

Energy Technology Data Exchange (ETDEWEB)

Seifarth, A. [Klinikum Augsburg, Klinik fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie, Augsburg (Germany); Roemer, F. [Klinikum Augsburg, Klinik fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie, Augsburg (Germany); Universitaetsklinikum Erlangen, Radiologisches Institut, Erlangen (Germany)

2015-03-01

zu Anpassungsreaktionen mit Ausbildung von Osteophyten am Unterrand des Humeruskopfs und Knorpeldefekten v. a. am Glenoid. Die Omarthrose ist haeufig koexistent mit anderen Veraenderungen der Schulter. In fortgeschrittenem Stadium beguenstigen sich Defekte der Rotatorenmanschette und eine Omarthrose gegenseitig. Degenerative Veraenderungen des Akromioklavikular(AC)-Gelenks kommen im Alter regelhaft vor, sind oft asymptomatisch und korrelieren nur maessig mit der Klinik. Eine symptomatische AC-Gelenk-Arthrose ist jedoch haeufig koexistent mit degenerativen Veraenderungen des Glenohumeralgelenks. Roentgenaufnahmen sind Teil der Basisdiagnostik, korrelieren jedoch schlecht mit der klinischen Symptomatik und sind nicht geeignet, um Fruehzeichen der Arthrose zu erkennen. Die Magnetresonanztomographie (MRT) weist eine deutlich hoehere Sensitivitaet zur Detektion von Knorpellaesionen auf und zeigt relevante Weichteilbefunde wie Labrum- und ligamentaere Veraenderungen, die im Rahmen einer Instabilitaet auftreten koennen. Bei der Diagnostik der Arthrose des AC-Gelenks ist die MRT den anderen Methoden in der Detaildiagnostik ueberlegen, insbesondere um klinisch relevante Befunde wie ein periartikulaeres Knochenmarkoedem oder eine begleitende AC-Gelenk-Kapsulitis beurteilen zu koennen. Fruehe degenerative Veraenderungen lassen sich mittels Roentgen nicht erkennen, bei klinischem Verdacht sollte eine MRT erfolgen Bei MRT-Untersuchungen ist die intravenoese Gabe von Kontrastmittel zur Beurteilung des Ausmasses einer Synovialitis bei symptomatischer Arthrose sinnvoll. Zur Planung des Gelenkersatzes sollte eine Schnittbildgebung erfolgen. (orig.)

Magnetic resonance image-guided brachytherapy for cervical cancer. Prognostic factors for survival

Energy Technology Data Exchange (ETDEWEB)

Kim, Yeon-Joo; Kim, Joo-Young [National Cancer Center, Proton Therapy Center, Goyang (Korea, Republic of); National Cancer Center, Center for Uterine Cancer, Goyang (Korea, Republic of); Kim, Youngkyong; Lim, Young Kyung; Jeong, Jonghwi [National Cancer Center, Proton Therapy Center, Goyang (Korea, Republic of); Jeong, Chiyoung [National Cancer Center, Proton Therapy Center, Goyang (Korea, Republic of); University of Ulsan College of Medicine, Department of Radiation Oncology, Asan Medical Center, Seoul (Korea, Republic of); Kim, Meyoung [National Cancer Center, Proton Therapy Center, Goyang (Korea, Republic of); Dongnam Inst. of Radiology and Medical Sciences, Research center, Busan (Korea, Republic of); Lim, Myong Cheol; Seo, Sang-Soo; Park, Sang-Yoon [National Cancer Center, Center for Uterine Cancer, Goyang (Korea, Republic of)

2016-12-15

The purpose of this work was to identify prognostic factors for survival after magnetic resonance image (MRI)-guided brachytherapy combined with external beam radiotherapy for cervical cancer. External beam radiotherapy of 45-50.4 Gy was delivered by either three-dimensional conformal radiotherapy or helical tomotherapy. Patients also received high-dose-rate MRI-guided brachytherapy of 5 Gy in 6 fractions. We analyzed 128 patients with International Federation of Gynecology and Obstetrics stage IB-IVB cervical cancer who underwent MRI-guided brachytherapy. Most patients (96 %) received concurrent chemotherapy. Pelvic lymph node metastases and para-aortic lymphadenopathies were found in 62 % and 14 % of patients, respectively. The median follow-up time was 44 months. Complete remission was achieved in 119 of 128 patients (93 %). The 5-year local recurrence-free, cancer-specific, and overall survival rates were 94, 89, and 85 %, respectively. Negative pelvic lymphadenopathy, gross tumor volume (GTV) dose covering 90 % of the target (GTV D90) of >110 Gy, and treatment duration ≤56 days were associated with better overall survival in univariate analyses. Multivariable analysis showed that GTV D90 of >110 Gy and treatment duration ≤56 days were possibly associated with overall survival with near-significant P-values of 0.062 and 0.073, respectively. The outcome of MRI-guided brachytherapy combined with external beam radiotherapy in patients with cervical cancer was excellent. GTV D90 of >110 Gy and treatment duration ≤56 days were potentially associated with overall survival. (orig.) [German] Ziel der Arbeit war es, prognostische Faktoren nach magnetresonanztomographisch (MRT-)gesteuerter Brachytherapie in Verbindung mit externer Strahlentherapie fuer Gebaermutterhalskrebs zu identifizieren. Externe Strahlentherapie von 45-50,4 Gy erfolgte entweder mittels dreidimensionaler konformaler Strahlentherapie oder helikaler Tomotherapie. Die Patientinnen erhielten auch

Hypotakse og indlejring

DEFF Research Database (Denmark)

Holsting, Alexandra Emilie Møller

2007-01-01

I artiklen foretager jeg en diskussion af kategorierne sætningskompleks og indlejret sætning inden for systemisk funktionel lingvistik (SFL). Problemet med den systemisk funktionelle beskrivelse er at den ikke formår at gøre rede for grammatiske forskelle på forskellige typer bisætninger, og jeg...

Institution, profession og samfund

DEFF Research Database (Denmark)

Olesen, Henning Salling; Warring, Niels; Nielsen, Steen Baagøe

2014-01-01

Artiklen introducerer en sociologisk forståelse af institutioner som både et konkret sted og en samfundsmæssig byggesten. De pædagogiske institutioners udvikling med samfundsmæssige transformationer danner rammen om en historisk og funktionel beskrivelse af det pædagogiske arbejde, og det spændin...

Physical Exercise and Multiple Sclerosis

DEFF Research Database (Denmark)

Dalgas, Ulrik

Baggrund: Kun få ikke-kontrollerede studier har undersøgt effekten af progressive styrketræning hos patienter med multipel sklerose (MS).  Formål: Undersøgelsens formål var at teste om progressiv styrketræning (PRT) af benene forbedrer muskelstyrke, muskelmorfologi, funktionel kapacitet, træthed,...

Neck Rhabdoid Tumors: Clinical Features and Consideration of Autologous Stem Cell Transplant.

Science.gov (United States)

Wolfe, Adam D; Capitini, Christian M; Salamat, Shahriar M; DeSantes, Kenneth; Bradley, Kristin A; Kennedy, Tabassum; Dehner, Louis P; Patel, Neha J

2018-01-01

Extrarenal malignant rhabdoid tumors (MRT) have a poor prognosis despite aggressive therapy. Adding high-dose chemotherapy with autologous stem cell rescue (HDC-ASCR) as consolidative therapy for MRT is controversial. We describe 2 patients, age 13 years and 19 months, with unresectable neck MRT. After chemotherapy and radiotherapy, both underwent HDC-ASCR and remain in remission over 4 years later. We reviewed all published cases of neck MRT, and found poorer outcomes and more variable age of presentation and time to progression than MRT at other sites. Neck MRT may represent a higher-risk subset of MRT, and addition of HDC-ASCR merits consideration.

Funktionel mitralinsufficiens efter His-ablation og pacemakerimplantation

DEFF Research Database (Denmark)

Lund, Janna; Gill, Sabine

2012-01-01

We describe the case of a 63 year-old patient with normal ejection fraction and trivial mitral regurgitation, who developed severe functional mitral incompetence (FMI) with pulmonary oedema the day after uncomplicated His ablation and implantation of VVI pacemaker. Mitral annuloplasty was perform...

Euthyroid goitre with and without functional autonomy: A comparison; Jodmangelstruma mit und ohne funktionelle Autonomie in der euthyreoten Phase: Ein Vergleich

Energy Technology Data Exchange (ETDEWEB)

Hillenhinrichs, H.; Emrich, D. [Goettingen Univ. (Germany). Abt. fuer Nuklearmedizin

1998-05-01

Analysis of functional autonomy in euthyroid goitre. Methods: In an area of moderate iodine deficiency 163 goitrous patients without and 179 with functional autonomy all clinically euthyroid were compared by sex, age, signs and symptoms, sonographic results, qualitative and quantitative scintigraphy without and with suppression, TRH test, hormone concentrations and iodine excretion in the urine. Results: Age, signs and symptoms, thyroid volume and structure did not contribute sufficiently to diagnosis. To detect functional autonomy quantitative scintigraphy under suppression was superior to the TRH test. Increased hormone concentrations were observed in 15% of patients with functional autonomy. A global {sup 99m}Tc thyroid uptake of {>=}3% under suppression indicates a higher risk of spontaneous hyperthyroidism. It was present in 20% of patients with functional autonomy. Conclusion: to diagnose and treat adequately functional autonomy in euthyroid goitre quantitative scintigraphy, determination of TSH and hormone concentrations are inevitable. (orig.) [Deutsch] Analyse der funktionellen Autonomie in der euthyreoten Phase. Methoden: Es wurden 163 klinisch euthyreote Patienten mit Jodmangelstruma ohne und 179 mit funktioneller Autonomie anhand von Geschlechtsverhaeltnis, Lebensalter, Beschwerden, Symptomen, sonographischem Befund, qualitativer und quantitativer Szintigraphie ohne und mit Suppression, TRH-Test, Hormonkonzentrationen und Jodausscheidung im Urin verglichen. Ergebnisse: Lebensalter, Beschwerden und Symptome, Schilddruesenvolumen und Echomuster lieferten keinen ausreichend sicheren Beitrag zur Diagnose. Die quantitative Szintigraphie war dem TRH-Test ueberlegen. Erhoehte Hormonkonzentrationen ergaben sich bei 15% der Patienten mit funktioneller Autonomie. Als Grenzwert fuer ein erhoehtes spontanes Hyperthyreoserisiko wurde eine globale thyreoidale {sup 99m}Tc-Aufnahme unter Suppression von {>=}3% ermittelt, die in 20% der Patienten mit funktioneller

Aestehtic, structural and functional transparency in design

DEFF Research Database (Denmark)

Thomsen, Bente Dahl; Madsen, Klaus

2011-01-01

Æstetisk, strukturel og funktionel transparens har vist sig at være særdeles velegnede triggere i kreative produktudviklingsprocesser, når målet er at opnå tydelig artikulering af de salgsfremmende værdier. Under analysen af konkurrerende produkter er de tre transparenter gode til fokusering på f...

Mellem lidelse og livsduelighed

DEFF Research Database (Denmark)

Dræby, Anders

Den psykiske lidelse i det moderne samfund er i det væsentlige et udtryk for vanskeligheder med de sociale og kulturelle krav om funktionel livstilpasning. Der præsenteres en anderledes og mere konstruktiv indgang til forståelse af liv og lidelse i vores samtid, der er funderet i et begreb om liv...

Interface

DEFF Research Database (Denmark)

kulturhistoriske udviklingsfaser. Den tegner også et billede af, hvordan interfacet forandrer vores musikkultur, og hvordan de digitale kunstværker udfordrer vores økonomi og jura. Interfacet er vor tids drøm om gennemsigtighed, om at nå ind bag formidlingen. Det er dog også andet og mere end funktionel teknologi...

Validating a visual version of the metronome response task.

Science.gov (United States)

Laflamme, Patrick; Seli, Paul; Smilek, Daniel

2018-02-12

The metronome response task (MRT)-a sustained-attention task that requires participants to produce a response in synchrony with an audible metronome-was recently developed to index response variability in the context of studies on mind wandering. In the present studies, we report on the development and validation of a visual version of the MRT (the visual metronome response task; vMRT), which uses the rhythmic presentation of visual, rather than auditory, stimuli. Participants completed the vMRT (Studies 1 and 2) and the original (auditory-based) MRT (Study 2) while also responding to intermittent thought probes asking them to report the depth of their mind wandering. The results showed that (1) individual differences in response variability during the vMRT are highly reliable; (2) prior to thought probes, response variability increases with increasing depth of mind wandering; (3) response variability is highly consistent between the vMRT and the original MRT; and (4) both response variability and depth of mind wandering increase with increasing time on task. Our results indicate that the original MRT findings are consistent across the visual and auditory modalities, and that the response variability measured in both tasks indexes a non-modality-specific tendency toward behavioral variability. The vMRT will be useful in the place of the MRT in experimental contexts in which researchers' designs require a visual-based primary task.

New aspects from legislation, guidelines and safety standards for MRI; Neues aus Gesetzen, Richtlinien und Sicherheitsstandards fuer die MRT

Energy Technology Data Exchange (ETDEWEB)

Muehlenweg, M. [Krankenhaus Martha-Maria Halle-Doelau, Institut fuer Radiologie, Halle (Saale) (Germany); Schaefers, G. [MR:comp GmbH, Gelsenkirchen (Germany); Trattnig, S. [Exzellenzzentrum Hochfeld-Magnetresonanz, Medizinische Universitaet Wien, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria)

2015-08-15

Betriebsanleitung der MR-Scanner. Die verpflichtenden Inhalte der Betriebsanleitung werden in einer zentralen Norm der International Electrotechnical Commission (IEC) 60601-2-33 geregelt. In dieser Norm wurde juengst die Anwendung statischer Magnetfelder in der MRT bis zu 8 Tesla (T) in der klinischen Routine (kontrollierte Betriebsart 1. Stufe) zugelassen. Die ebenfalls notwendige CE-Zertifizierung der Ultrahochfeldscanner (7-8 T) in Europa ist fuer zukuenftige Geraete zu erwarten. Bestehende Installationen werden nicht automatisch zertifiziert, sondern behalten ihren experimentellen Status. Die aktuelle Erweiterung der IEC 60601-2-33 fuehrt eine neue Zusatzoption, die sog. ''fixed parameter option'' (FPO) ein. Diese Option kann zusaetzlich zu den etablierten Betriebsarten geschaltet werden und definiert eine fixe Geraetekonstellation und bestimmte Parameter des Energieoutputs von MR-Scannern, die zukuenftig die Untersuchungen von Implantatpatienten vereinfachen soll. Die Beschaeftigung schwangerer Mitarbeiterinnen in einer MRT-Einrichtung ist nach wie vor nicht allgemein in Europa geregelt. In Deutschland und Oesterreich wurden 2014 in Teilregionen Beschaeftigungsverbote fuer Schwangere und Stillende im der MR-Kontrollzone (0,5 mT) erteilt. Zugrunde liegt die meist ungeklaerte Frage der Anwendbarkeit von Grenzwerten fuer Beschaeftigte (Extremitaetenexposition fuer statische Magnetfelder bis 8 T erlaubt) oder der Grenzwerte fuer die Allgemeinbevoelkerung (maximal bis 400 mT). Das Verwerfen von Muttermilch nach i.v.-Gabe von gadoliniumhaltigen Kontrastmitteln bei einer stillenden Frau wird laut Gesellschaft fuer urogenitale Radiologie (ESUR) nur noch bei Gabe von Kontrastmitteln der Nephrogenic-systemic-fibrosis(NSF)-Hochrisikoklasse empfohlen. (orig.)

MR of the liver in Wilson`s disease; MRT der Leber bei Morbus Wilson

Energy Technology Data Exchange (ETDEWEB)

Vogl, T.J. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Steiner, S. [Klinikum Grosshadern, Radiologische Klinik und Poliklinik, Univ. Muenchen (Germany); Hammerstingl, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Schwarz, S. [Klinikum Grosshadern, Neurologische Klinik, Univ. Muenchen (Germany); Kraft, E. [Klinikum Grosshadern, Neurologische Klinik, Univ. Muenchen (Germany); Weinzierl, M. [Klinikum Grosshadern, 2. Medizinische Klinik, Univ. Muenchen (Germany); Felix, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany)

1994-01-01

To show that Wilson`s disease is one likely cause of multiple low-intensity nodules of the liver we obtained MR images in 16 patients with clinically and histopathologically confirmed Wilson`s disease. Corresponding to morphological changes MRI enabled the subdivision of the patients into two groups. Using a T{sub 2}-weighted spin-echo sequence (TR/TE=2000/45-90) liver parenchyma showed multiple tiny low-intensity-nodules surrounded by high-intensity septa in 10 out of 16 patients. 5 patients had also low-intensity nodules in T{sub 1}-weighted images (TR/TE=600/20). In patients of this group histopathology revealed liver cirrhosis (n=7) and fibrosis (n=2). Common feature of this patient group was marked inflammatory cell infiltration into fibrous septa, increase of copper concentration in liver parenchyma and distinct pathological changes of laboratory data. In the remaining 6 patients no pathological change of liver morphology was demonstrated by MRI corresponding to slight histopathological changes of parenchyma and normal laboratory data. As low-intensity nodules surrounded by high intensity septa can be demonstrated in patients with marked inflammatory infiltration of liver parenchyma MRI may help to define Wilson patients with poorer prognosis. In patients with low-intensity nodules of the liver and unknown cause of liver cirrhosis laboratory data and histopathology should be checked when searching for disorders of copper metabolism. (orig.) [Deutsch] Im Rahmen einer prospektiven Studie wurde die Leber bei 16 Patienten mit klinisch gesichertem Morbus Wilson magnetresonanztomographisch untersucht. Zum Einsatz kamen T{sub 1}- und T{sub 2}-gewichtete Spin-Echo-Sequenzen vor und nach Applikation von Gd-DTPA (0,1 mmol/kg KG). Anhand der MRT-Befunde konnten zwei unterschiedliche Patientenkollektive definiert werden. 10 Patienten wiesen in der T{sub 2}-gewichteten Sequenz hypointense Regeneratknoten auf und zeigten histopathologisch ausgepraegte Befunde einer

Relapsing mastitis 17 years after the augmentation mammoplasty with PAAG followed by follicular Non-Hodgkin's lymphoma - MRT, US and PET /CT findings

International Nuclear Information System (INIS)

Spirdonov, J.; Sedloev, T.

2017-01-01

A case of a 51-year-old woman with mastitis in her right breast 17 years after Augmentation Mammoplasty with PAAG produced in Ukraine is presented, the MRI and mammary US findings are discussed. Solid areas in the background of the non-structural gel are established, hardly to be distinguished from primary mammary lesions. At a control US examination 6 months after the surgical intervention, an increase in new l.n. in the right axilla is established. The biopsy performed discovered the histological features for follicular non-Hodgkin's lymphoma grade 2, CD 20 (+) sex. The links of the lymphoma as a systemic manifestation of the local cytotoxic effect in the C-myc gene expression of the medical polyacrylamide hydrogel is questionable. In all women after Augmentation Mammoplasty with PAAG 6-month follow-ups with US are recommended, completed with MRI if needed and, annual blood tests as well. For equivocal clinical examinations and imaging studies, proceed to a FNB or Cor biopsy under US control. Key words: Mastitis. Augmentation MAMMOPLASTY. PAAG, US. MRT. PET/CT Follicular Non-Hodgkin's Lymphoma [bg

Magnetic resonance tomography in eclampsia

International Nuclear Information System (INIS)

Uhlig, U.

1995-01-01

Eclampsia is a rare but severe complication during the course of a pregnancy. The CT-findings at the brain are well known. Reports on MRT-findings are limited, however, especially in German literature. We describe the MRT picture of the cerebral changes caused by eclampsia and discuss the advantages of MRT in comparison with CT. The use of contrast agents with MRT shows breakdown of blood-brain barrier but does not provide any information of therapeutical consequences and should be avoided during pregnancy. An early and targeted use of MRT in any case of unclear or suspicious neurological symptoms during pregnancy is recommended. MRT supports differential diagnosis regarding non pregnancy-related cerebral disease and can be helpful for therapy planning in cases of preeclampsia. Additionally, MRT offers the possibility to control the effect of therapy with regard to brain damage. (orig.) [de

Tux fährt Bahn

OpenAIRE

Sontag, Ralph

2007-01-01

Modelleisenbahnen können Kinderspielzeug oder anspruchsvolles Hobby sein. Heute fahren viele Bahnen digital und werden mittels Digital Command Control (DCC) gesteuert. Im Vortrag sollen die Grundlagen des Protokolls erläutert und die Grundfunktionen mittels des Decoder Programmers SPROG II unter Linux ausprobiert werden.

Betaler det sig? Fleksibilitet og løn i den danske flexicurity-model

DEFF Research Database (Denmark)

Ibsen, Flemming

2007-01-01

Indkomstsikkerhed er at bevæge sig fra et job til at andet og få en højere løn, men er det tilfældet i dan danske flexicurity-model, betaler det sig at være fleksibel? Belønnes numerisk ekstern fleksibiblitet højrere end intern funktionel fleksibilbitet? Artiklen viser, at det bedst kan betale si...

QTL-Kartierung und funktionelle Kandidatengenanalyse für das Merkmal Totgeburt in einer fortgeschrittenen Fleckvieh- x Red-Holstein-Rückkreuzungspopulation

OpenAIRE

Gomeringer, Verena

2007-01-01

Das Ziel dieser Arbeit war die Kartierung eines QTL mit Effekt auf paternalen Kalbeverlauf und paternale Totgeburt auf Bos Taurus Autosom 9 (BTA09) in einer fortgeschrittenen Fleckvieh x Red-Holstein Rückkreuzungspopulation mit positioneller und funktioneller Kandidatengenanalyse. Dazu wurden Untersuchungen mit verschiedenen Kartierungsdesigns in Granddaughter und Daughter Designs durchgeführt. Intervallkartierung und Linkage / Linkage-Disequilibrium-Kartierung wurden verwendet um den QTL ...

Magnetic resonance tomography in eclampsia; Magetresonanztomographie bei Eklampsie

Energy Technology Data Exchange (ETDEWEB)

Uhlig, U. [St.-Vincentius-Krankenhaeuser, Karlsruhe (Germany). Radiologische Klinik

1995-05-01

Eclampsia is a rare but severe complication during the course of a pregnancy. The CT-findings at the brain are well known. Reports on MRT-findings are limited, however, especially in German literature. We describe the MRT picture of the cerebral changes caused by eclampsia and discuss the advantages of MRT in comparison with CT. The use of contrast agents with MRT shows breakdown of blood-brain barrier but does not provide any information of therapeutical consequences and should be avoided during pregnancy. An early and targeted use of MRT in any case of unclear or suspicious neurological symptoms during pregnancy is recommended. MRT supports differential diagnosis regarding non pregnancy-related cerebral disease and can be helpful for therapy planning in cases of preeclampsia. Additionally, MRT offers the possibility to control the effect of therapy with regard to brain damage. (orig.) [Deutsch] Die Eklampsie ist eine seltene aber erhebliche Komplikation im Verlauf einer Schwangerschaft. Die computertomographischen Veraenderungen im Gehirn sind bekannt. Mitteilungen von kernspintomographischen Befunden finden sich vor allem in der deutschen Literatur noch selten. Wir beschreiben das kernspintomographische Bild der zerebralen Veraenderungen bei Eklampsie und diskutieren die Vorteile der MRT im Vergleich zur CT. Die Gabe von Kontrastmittel bei der MRT weist zwar die Blut-Hirn-Schrankenstoerung nach, bringt aber keine therapeutisch relevanten Informationen. Sie sollte waehrend der Schwangerschaft vermieden werden. Ein frueher und gezielter Einsatz der MRT bei unklaren oder verdaechtigen neurologischen Symptomen waehrend der Schwangerschaft ist sinnvoll. Die MRT unterstuetzt die Differentialdiagnose in bezug auf nicht schwangerschaftsbezogene zerebrale Leiden und kann fuer die Therapie richtungweisend sein, wenn die Gestose noch nicht ausgepraegt ist. (orig.)

Pathological changes of the chemosensory function in multiple sclerosis. An MRI study; Pathologische Veraenderungen der Chemosensorik mittels Kernspintomografie bei Multipler Sklerose. Eine MRT-Studie

Energy Technology Data Exchange (ETDEWEB)

Schmidt, F.A.; Harms, L. [Charite Campus Mitte, Berlin (Germany). Dept. of Neurology - Consultation Service for Multiple Sclerosis; Fleiner, F.; Dahlslett, B.; Goektas, Oe. [Charite Campus Mitte, Berlin (Germany). Dept. of Otolaryngology, Head and Neck Surgery; Bohner, G.; Erb, K.; Luedemann, L. [Charite Campus Mitte, Berlin (Germany). Dept. of Radiology

2011-06-15

Purpose: To examine possible causes for olfactory and gustatory dysfunction in MS patients in a prospective study with MRI. Materials and Methods: 30 MS patients (21 women, 11 men, 22 - 65 years, diameter 42 years) were examined by MRI. The olfactory bulb (OB) and olfactory brain volume was correlated with the number and volume of MS lesions in the olfactory brain and the non-olfactory brain. Olfactory testing was performed using the Threshold-Discrimination-Identification Test (TDI), and gustatory function was tested using the Taste-Strips-Test (TST). Results: 33 % of the MS patients displayed olfactory dysfunction (8 % of the control group), and 17 % displayed gustatory dysfunction (5 % of the control group). There was a correlation between the olfactory brain volume and the number (r = -0.38, p < 0.05) and volume (r = -0.38, p < 0.05) of MS lesions in the olfactory brain. The olfactory brain volume correlated with the number of MS lesions in the non-olfactory brain (r = -0.48, p < 0.05). The volume of the left OB correlated with the volume of MS lesions in the olfactory brain (r = -0.42, p < 0.05), the number (r = 0.37, p < 0.05) and volume (r = 0.4, p < 0.05) of lesions in the left part of the olfactory brain and with the TST score (r = -0.45, p < 0.05). The TST score correlated with the volume of lesions in the left (r = -0.45, p < 0.05) and right part (r = -0.53, p < 0.05) of the olfactory brain. The TST score correlated with the number of lesions in the non-olfactory brain (r = -0.48, p < 0.05). Conclusion: The correlation between a higher number and volume of MS lesions in the olfactory brain with a decreased OB and olfactory brain volume could help to explain olfactory and gustatory dysfunction in MS patients. Just the left OB correlated with the number and volume of lesions in the olfactory brain. Manual segmentation was a suitable method for measuring OB and olfactory brain volume. (orig.)

Calculation of Friction Coefficient and Analysis of Fluid Flow in a Stepped Micro-Channel for Wide Range of Knudsen Number Using Lattice Boltzmann (MRT Method

Directory of Open Access Journals (Sweden)

Y. Bakhshan

2015-01-01

Full Text Available Micro scale gas flows has attracted significant research interest in the last two decades. In this research, the fluid flow of gases in the stepped micro-channel at a wide range of Knudsen number has been analyzed with using the Lattice Boltzmann (MRT method. In the model, a modified second-order slip boundary condition and a Bosanquet-type effective viscosity are used to consider the velocity slip at the boundaries and to cover the slip and transition regimes of flow and to gain an accurate simulation of rarefied gases. It includes the slip and transition regimes of flow. The flow specifications such as pressure loss, velocity profile, streamline and friction coefficient at different conditions have been presented. The results show good agreement with available experimental data. The calculation shows that the friction coefficient decreases with increasing the Knudsen number and stepping the micro-channel has an inverse effect on the friction coefficient. Furthermore, a new correlation is suggested for calculation of the friction coefficient in the stepped micro-channel as below: C_f Re  = 3.113+2.915/(1 +2 Kn+ 0.641 exp⁡(3.203/(1 + 2 Kn

Engineered Modular Recombinant Transporters: Application of New Platform for Targeted Radiotherapeutic Agents to α-Particle Emitting 211At

International Nuclear Information System (INIS)

Rosenkranz, Andrey A.; Vaidyanathan, Ganesan; Pozzi, Oscar R.; Lunin, Vladimir G.; Zalutsky, Michael R.; Sobolev, Alexander S.

2008-01-01

Purpose: To generate and evaluate a modular recombinant transporter (MRT) for targeting 211 At to cancer cells overexpressing the epidermal growth factor receptor (EGFR). Methods and Materials: The MRT was produced with four functional modules: (1) human epidermal growth factor as the internalizable ligand, (2) the optimized nuclear localization sequence of simian vacuolating virus 40 (SV40) large T-antigen, (3) a translocation domain of diphtheria toxin as an endosomolytic module, and (4) the Escherichia coli hemoglobin-like protein (HMP) as a carrier module. MRT was labeled using N-succinimidyl 3-[ 211 At]astato-5-guanidinomethylbenzoate (SAGMB), its 125 I analogue SGMIB, or with 131 I using Iodogen. Binding, internalization, and clonogenic assays were performed with EGFR-expressing A431, D247 MG, and U87MG.wtEGFR human cancer cell lines. Results: The affinity of SGMIB-MRT binding to A431 cells, determined by Scatchard analysis, was 22 nM, comparable to that measured before labeling. The binding of SGMIB-MRT and its internalization by A431 cancer cells was 96% and 99% EGFR specific, respectively. Paired label assays demonstrated that compared with Iodogen-labeled MRT, SGMIB-MRT and SAGMB-MRT exhibited more than threefold greater peak levels and durations of intracellular retention of activity. SAGMB-MRT was 10-20 times more cytotoxic than [ 211 At]astatide for all three cell lines. Conclusion: The results of this study have demonstrated the initial proof of principle for the MRT approach for designing targeted α-particle emitting radiotherapeutic agents. The high cytotoxicity of SAGMB-MRT for cancer cells overexpressing EGFR suggests that this 211 At-labeled conjugate has promise for the treatment of malignancies, such as glioma, which overexpress this receptor

"The hidden dimension": Kulturdimensionen als Orientierung in der interkulturellen Zusammenarbeit

OpenAIRE

Nagy, Carolin

2003-01-01

Kulturdimensionen sind seit den Untersuchungen von Hall, Brislin, Hofstede und Trompenaars/ Hampden-Turner ein gängiges Mittel, vor allem in Trainings, zur Beschreibung interkultureller Kommunikationsschwierigkeiten, Missverständnisse und kultureller Differenzen überhaupt.Ob sie jedoch auch ein nützliches und taugliches Mittel dafür sind ist sehr umstritten.

AcEST: DK954018 [AcEST

Lifescience Database Archive (English)

Full Text Available I8 Definition sp|Q9D0I8|MRT4_MOUSE mRNA turnover protein 4 homolog OS=Mus musculus Align length 152 Score (b...ignments: (bits) Value sp|Q9D0I8|MRT4_MOUSE mRNA turnover protein 4 homolog OS=Mus musc... 142 1e-33 sp|A4FV84|MRT4_BOVIN mRNA turnov...er protein 4 homolog OS=Bos taur... 142 1e-33 sp|Q9UKD2|MRT4_HUMAN mRNA turnover... protein 4 homolog OS=Homo sap... 140 5e-33 sp|Q86HD3|MRT4_DICDI mRNA turnover prote...in 4 homolog OS=Dictyost... 127 3e-29 sp|Q9USZ6|MRT4_SCHPO mRNA turnover protein 4 homolog OS=Schizosa... 10

AcEST: DK954898 [AcEST

Lifescience Database Archive (English)

Full Text Available d A4FV84 Definition sp|A4FV84|MRT4_BOVIN mRNA turnover protein 4 homolog OS=Bos taurus Align length 160 Scor...t alignments: (bits) Value sp|A4FV84|MRT4_BOVIN mRNA turnover protein 4 homolog OS=Bos taur... 153 6e-37 sp|...Q9D0I8|MRT4_MOUSE mRNA turnover protein 4 homolog OS=Mus musc... 152 8e-37 sp|Q9UKD2|MRT4_HUMAN mRNA turno...ver protein 4 homolog OS=Homo sap... 151 2e-36 sp|Q86HD3|MRT4_DICDI mRNA turnover p...rotein 4 homolog OS=Dictyost... 140 5e-33 sp|Q7S302|MRT4_NEUCR mRNA turnover protein 4 homolog OS=Neurospo..

Measurement of the filling height of transient two-phase surge flows in pipelines by means of electronics; Messung der Fuellhoehe von transienten Zweiphasenschwallstroemungen in Rohrleitungen mittels Ultraschall

Energy Technology Data Exchange (ETDEWEB)

Hofmann, B.; Rockstroh, M. [Technische Univ. Dresden (Germany). Inst. fuer Energiemaschinen und Maschinenlabor

1997-12-01

The aim of the ultrasonic measurements was the determination of the time course of the level of a transient surge flow with swirl and waves in partly filled roughly horizontally laid pipelines. The running time of the ultrasonic waves from the test head to the liquid surface and back was measured for this purpose. The course of the stress was recorded digitally and was evaluated with the aid of software. Waves, swirl, turbulence of flow and introduced test bodies in the flow caused typical echoes, which had to be taken into account in the evaluation. As the test head was fitted on the outside of the pipe (clamp-on technique), the pipe wall thickness and the speed of sound in the pipe wall had to be included in the calculation of filling height by means of a correction. [Deutsch] Ziel der Ultraschallmessungen war die Bestimmung des zeitlichen Verlaufes der Fuellhoehe einer transienten, drall- und wellenbehafteten Schwallstroemung in teilgefuellten, etwa horizontal verlegten Rohrleitungen. Hierzu wurde die Laufzeit der Ultraschallwellen vom Pruefkopf zur Fluessigkeitsoberflaeche und zurueck gemessen. Die Laufzeit der Ultraschallwellen wurde auf eine quasi-analog elektrische Spannung abgebildet. Der Spannungsverlauf wurde digital aufgezeichnet und softwaregestuetzt ausgewertet. Wellen, Drall, Stroemungsturbulenzen sowie eingebrachte Pruefkoerper in der Stroemung hatten typische Echoerscheinungen zur Folge, die bei der Auswertung zu beruecksichtigen waren. Da der Pruefkopf aussen am Rohr angebracht war (clamp-on-Technik), musste die Rohrwandstaerke und die Schallgeschwindigkeit in der Rohrwandung mittels eines Korrekturgliedes in die Fuellhoehenberechnung eingezogen werden. (orig.)

Engineering geological and hydrogeological invstigations for storage of medium and low-activity nuclear waste at Cernavoda, Romania. Soil stabilisation using the CONSOLID system; Ingenieurgeologische und hydrogeologische Untersuchungen zur Lagerung mittel- und schwachradioaktiver Abfaelle in Cernavoda Rumaenien. Baugrundstabilisierung mit dem CONSOLID-System

Energy Technology Data Exchange (ETDEWEB)

Giurgea, V.; Merkler, G.P.; Hoetzl, H.; Hannich, D. [Karlsruhe Univ. (T.H.) (Germany). Lehrstuhl fuer Angewandte Geologie

1998-12-31

In Cernavoda/Romania investigations and planning from a low and middle radioactive waste disposal site have been carried out. A multitude of hydrogeological, geological, engineering geological criteria`s and constructional security measures were examined with respect to the strict regulations for such a waste site. This studies and measures are shortly analyzed and discussed in this paper. In accordance with the selection criteria for such a hazardous waste site, several laboratory and `in situ` tests, soil-mechanic studies, numerical modeling and foundation tests for soil stabilization with the CONSOLID-System are presented. (orig.) [Deutsch] Zur Einhaltung der strengen Vorgaben, die bei einem Deponiestandort fuer mittel- und schwachradioaktive Abfaelle gestellt werden, sind in Cernavoda/Rumaenien eine Vielzahl von hydrogeologischen und ingenieurgeologischen Untersuchungen sowie bautechnischen Sicherungsmassnahmen vorgesehen, die im Rahmen dieser Publikation kurz analysiert und diskutiert werden. Im Zusammenhang mit den geologischen und hydrogeologischen Auswahlkriterien des Standortes werden eine Reihe von Labor- und `in situ` Untersuchungen, Modellrechnungen sowie Baugrundstabilisierungsmassnahmen mit dem CONSOLID-System vorgestellt. (orig.)

SU-E-T-45: Antibody Mean Residence Time in Blood and Its Correlation with Protein Molecular Weight

Energy Technology Data Exchange (ETDEWEB)

Kwok, C; Williams, L [Retired from City of Hope Medical Center, Arcadia, CA (United States)

2014-06-01

Purpose: Animal biodistribution data are required prior to introducing a new radiopharmaceutical into clinical trials. Protein engineering, using recombinant DNA techniques can produce a large number of related (cognate) antibodies to a given molecular target. Thus, it is important that these constructs be numerically related to one another via a single criterion. In the following, we use the mean residence time (MRT) in murine blood as this criterion. Methods: Five cognate anti-CEA (Carcinoembryonic Antigen) antibodies were compared with regard to their MRT in whole blood of CEA-positive tumor-bearing (LS174T) mice. MRT was defined by blood AUC (area under the curve) divided by the initial blood uptake value; all in units of percent injected dose per gram (%ID/g). Cognates included single chain scFv (25 kDa), diabody (50 kDa), minibody (80 kDa), F(ab')2 (120 kDa), and intact (155 kDa) forms of the murine cT84.66 antibody against CEA. All were labeled with radioactive iodine. Results: The agents, in the sequence listed, exhibited MRT values of 1.16 +/- 0.01 h, 0.99 h, 5.06 +/- 0.70 h, 6.61 +/- 0.36 h, and 59.3 +/- 2.4 h respectively. Because of the monotonic nature of the sequence, a linear correlation analysis was performed between molecular weight (MW) and MRT or ln(MRT) of the 5 proteins. Probability of random correlation was 0.10 for MRT and 0.01 for ln(MRT). Conclusion: MRT values of cognate anti-CEA antibodies were found to be a monotonically increasing sequence with respect to MW. Cognate MW values correlated best to ln(MRT) of the protein species. Thus MRT was proportional to an exponential function of molecular weight. The extended intact antibody circulation time presumably reflected its relatively maximal MW. Presence of an intact FC segment on this native antibody may also have influenced these results.

SU-E-T-45: Antibody Mean Residence Time in Blood and Its Correlation with Protein Molecular Weight

International Nuclear Information System (INIS)

Kwok, C; Williams, L

2014-01-01

Purpose: Animal biodistribution data are required prior to introducing a new radiopharmaceutical into clinical trials. Protein engineering, using recombinant DNA techniques can produce a large number of related (cognate) antibodies to a given molecular target. Thus, it is important that these constructs be numerically related to one another via a single criterion. In the following, we use the mean residence time (MRT) in murine blood as this criterion. Methods: Five cognate anti-CEA (Carcinoembryonic Antigen) antibodies were compared with regard to their MRT in whole blood of CEA-positive tumor-bearing (LS174T) mice. MRT was defined by blood AUC (area under the curve) divided by the initial blood uptake value; all in units of percent injected dose per gram (%ID/g). Cognates included single chain scFv (25 kDa), diabody (50 kDa), minibody (80 kDa), F(ab')2 (120 kDa), and intact (155 kDa) forms of the murine cT84.66 antibody against CEA. All were labeled with radioactive iodine. Results: The agents, in the sequence listed, exhibited MRT values of 1.16 +/- 0.01 h, 0.99 h, 5.06 +/- 0.70 h, 6.61 +/- 0.36 h, and 59.3 +/- 2.4 h respectively. Because of the monotonic nature of the sequence, a linear correlation analysis was performed between molecular weight (MW) and MRT or ln(MRT) of the 5 proteins. Probability of random correlation was 0.10 for MRT and 0.01 for ln(MRT). Conclusion: MRT values of cognate anti-CEA antibodies were found to be a monotonically increasing sequence with respect to MW. Cognate MW values correlated best to ln(MRT) of the protein species. Thus MRT was proportional to an exponential function of molecular weight. The extended intact antibody circulation time presumably reflected its relatively maximal MW. Presence of an intact FC segment on this native antibody may also have influenced these results

Coxarthrosis; Koxarthrose

Energy Technology Data Exchange (ETDEWEB)

Imhof, H.; Czerny, C.; Gahleitner, A.; Grampp, S.; Kainberger, F.; Krestan, C. [Osteologie, Radiodiagnostik, AKH Wien (Austria); Sulzbacher, I. [Institut fuer Klinische Pathologie, AKH Wien (Austria)

2002-06-01

;'activated'' osteoarthritis under standard therapy, unclear joint-pain and before any arthroscopy. (orig.) [German] Koxarthrosen gehoeren zu den am haeufigsten auftretenden Arthrosen. Es besteht eine geringe Praevalenz des maennlichen Geschlechts. Aetiologisch werden primaere and sekundaere Koxarthrosen unterschieden. Primaere (idiopathische) sind aetiologisch unklar, sekundaere beruhen auf bekannten Aetiologien (z. B. Uebergewicht, repetitive Traumen, Fehlstellung bzw. Fehlhaltung, Muskel bzw. Sehnenimbalanz etc.). Pathophysiologisch finden sich bei Arthrosen Knorpel-, Subchondralregion-, Synovialis-, Gelenkfluessigkeitsveraenderungen sowie Abnormitaeten in den periartikulaeren Muskeln. Waehrend im Knorpel stadienhaft oedematoese Schwellung, Defekt mit Riss, Fibrillation, Glatzenbildung und Knorpelregeneratbildung sowie Gelenkspaltverschmaelerung auftreten, zeigen sich subchondral kleinste Oedembildungen, Nekrosen, evtl. Mikrofrakturen und Demineralisation sowie die bekannten subchondralen Sklerosierungen, Zystenbildungen und osteophytaeren Neubildungen. In spaeterer Folge kommt es zu Deformierungen und Fehlstellung. Letztere Veraenderungen sind mittels konventionellen Roentgenaufnahmen, CT und MRT gut abgrenzbar.Von zunehmender Bedeutung ist heute auch die Diagnostik sog. Praearthrosen. Dazu zaehlen aetiologisch u. a. unterschiedliche Fehlstellungen, Fehlformen, evtl. Labrumpathologien sowie die oben genannten Sehnen- und Muskelimbalanzen.Koxarthrosen werden in 3 prognostisch unterschiedliche Typen differenziert, abhaengig von der Migration des Kopfes: die laterokraniale als haeufigste, die mediokaudale und die seltene axiale. Ihre Entstehung duerfte auf unterschiedliche Mechanismen zurueckgehen.Die bildgebende Diagnostik erfolgt beim Vorliegen einer entsprechenden klinischen Symptomatik. Basis der Bildgebung ist heute unveraendert das konventionelle Roentgenbild, gefolgt von CT und MRT. Zur Diagnostik der ''aktivierten Arthrose'' wird nach wie vor die

Working memory in volunteers and schizophrenics using BOLD fMRI; Das Arbeitsgedaechtnis bei Gesunden und bei Schizophrenen: Untersuchungen mit BOLD-fMRT

Energy Technology Data Exchange (ETDEWEB)

Giesel, F.L. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie (Germany); Deutsches Krebsforschungszentrum (DKFZ), Abteilung Radiologie, Heidelberg (Germany); Hohmann, N. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie (Germany); Psychiatrische Universitaetsklinik Heidelberg, Sektion Gerontopsychiatrie (Germany); Seidl, U.; Kress, K.R.; Schoenknecht, P.; Schroeder, J. [Psychiatrische Universitaetsklinik Heidelberg, Sektion Gerontopsychiatrie (Germany); Kauczor, H.-U.; Essig, M. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie (Germany)

2005-02-01

Functional magnetic resonance imaging uses the blood oxygen level-dependent effect (BOLD MRI) for noninvasive display of cerebral correlatives of cognitive function. The importance for the understanding of physiological and pathological processes is demonstrated by investigations of working memory in schizophrenics and healthy controls. Working memory is involved in processing rather than storage of information and therefore is linked to complex processes such as learning and problem solving. In schizophrenic psychosis, these functions are clearly restricted. Training effects in the working memory task follow an inverse U-shape function, suggesting that cerebral activation reaches a peak before economics of the brain find a more efficient method and activation decreases. (orig.) [German] Die funktionelle Magnetresonanztomographie (fMRT) nutzt den ''blood oxygen level dependent effect'' (BOLD-Effekt) zur nichtinvasiven Darstellung zerebraler Korrelate kognitiver Funktionen. Die Bedeutung dieses Verfahrens fuer das Verstaendnis physiologischer und pathologischer Prozesse wird anhand von Untersuchungen zum Arbeitsgedaechtnis bei Schizophrenen und gesunden Kontrollpersonen verdeutlicht. Das Arbeitsgedaechtnis dient weniger der Speicherung, sondern vielmehr der Verarbeitung von Informationen und ist deshalb in komplexe Prozesse wie Lernen und Problemloesen eingebunden. Im Rahmen schizophrener Psychosen kommt es zu einer deutlichen Einschraenkung dieser Funktionen. Erwartungsgemaess zeigen sich unter Durchfuehrung eines Arbeitsgedaechtnisparadigmas Unterschiede in der zerebralen Aktivitaet, die jedoch bei den Erkrankten unter Therapie prinzipiell reversibel sind. Von Interesse sind auch Trainingseffekte bei Gesunden, wobei eine verminderte Aktivierung nach Training auf eine ''Oekonomisierung'' schliessen laesst. (orig.)

Better Efficacy of Synchrotron Spatially Microfractionated Radiation Therapy Than Uniform Radiation Therapy on Glioma

International Nuclear Information System (INIS)

Bouchet, Audrey; Bräuer-Krisch, Elke; Prezado, Yolanda; El Atifi, Michèle; Rogalev, Léonid; Le Clec'h, Céline; Laissue, Jean Albert; Pelletier, Laurent; Le Duc, Géraldine

2016-01-01

Purpose: Synchrotron microbeam radiation therapy (MRT) is based on the spatial fractionation of the incident, highly focused synchrotron beam into arrays of parallel microbeams, typically a few tens of microns wide and depositing several hundred grays. This irradiation modality was shown to have a high therapeutic impact on tumors, especially in intracranial locations. However, mechanisms responsible for such a property are not fully understood. Methods and Materials: Thanks to recent progress in dosimetry, we compared the effect of MRT and synchrotron broad beam (BB) radiation therapy delivered at comparable doses (equivalent to MRT valley dose) on tumor growth control and on classical radiobiological functions by histologic evaluation and/or transcriptomic analysis. Results: MRT significantly improved survival of rats bearing 9L intracranial glioma compared with BB radiation therapy delivered at a comparable dose (P<.001); the efficacy of MRT and BB radiation therapy was similar when the MRT dose was half that of BB. The greater efficacy of MRT was not correlated with a difference in cell proliferation (Mki67 and proliferating cell nuclear antigen) or in transcriptomic stimulation of angiogenesis (vascular endothelial growth factor A or tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 2) but was correlated with a higher cell death rate (factor for apoptosis signals) and higher recruitment of macrophages (tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 1 and CD68 transcripts) a few days after MRT. Conclusions: These results show the superiority of MRT over BB radiation therapy when applied at comparable doses, suggesting that spatial fractionation is responsible for a specific and particularly efficient tissue response. The higher induction of cell death and immune cell activation in brain tumors treated by MRT may be involved in such responses.

Better Efficacy of Synchrotron Spatially Microfractionated Radiation Therapy Than Uniform Radiation Therapy on Glioma

Energy Technology Data Exchange (ETDEWEB)

Bouchet, Audrey, E-mail: audrey.m.bouchet@gmail.com [Université Grenoble Alpes, Grenoble Institut des Neurosciences, Grenoble (France); Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble (France); Bräuer-Krisch, Elke; Prezado, Yolanda [Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble (France); El Atifi, Michèle [Université Grenoble Alpes, Grenoble Institut des Neurosciences, Grenoble (France); Grenoble University Hospital, Grenoble (France); Rogalev, Léonid; Le Clec' h, Céline [Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble (France); Laissue, Jean Albert [University of Bern, Bern (Switzerland); Pelletier, Laurent, E-mail: laurent.pelletier@ujf-grenoble.fr [Université Grenoble Alpes, Grenoble Institut des Neurosciences, Grenoble (France); Grenoble University Hospital, Grenoble (France); Le Duc, Géraldine [Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble (France)

2016-08-01

Purpose: Synchrotron microbeam radiation therapy (MRT) is based on the spatial fractionation of the incident, highly focused synchrotron beam into arrays of parallel microbeams, typically a few tens of microns wide and depositing several hundred grays. This irradiation modality was shown to have a high therapeutic impact on tumors, especially in intracranial locations. However, mechanisms responsible for such a property are not fully understood. Methods and Materials: Thanks to recent progress in dosimetry, we compared the effect of MRT and synchrotron broad beam (BB) radiation therapy delivered at comparable doses (equivalent to MRT valley dose) on tumor growth control and on classical radiobiological functions by histologic evaluation and/or transcriptomic analysis. Results: MRT significantly improved survival of rats bearing 9L intracranial glioma compared with BB radiation therapy delivered at a comparable dose (P<.001); the efficacy of MRT and BB radiation therapy was similar when the MRT dose was half that of BB. The greater efficacy of MRT was not correlated with a difference in cell proliferation (Mki67 and proliferating cell nuclear antigen) or in transcriptomic stimulation of angiogenesis (vascular endothelial growth factor A or tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 2) but was correlated with a higher cell death rate (factor for apoptosis signals) and higher recruitment of macrophages (tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 1 and CD68 transcripts) a few days after MRT. Conclusions: These results show the superiority of MRT over BB radiation therapy when applied at comparable doses, suggesting that spatial fractionation is responsible for a specific and particularly efficient tissue response. The higher induction of cell death and immune cell activation in brain tumors treated by MRT may be involved in such responses.

Synchrotron microbeam radiation therapy induces hypoxia in intracerebral gliosarcoma but not in the normal brain

International Nuclear Information System (INIS)

Bouchet, Audrey; Lemasson, Benjamin; Christen, Thomas; Potez, Marine; Rome, Claire; Coquery, Nicolas; Le Clec’h, Céline; Moisan, Anaick; Bräuer-Krisch, Elke; Leduc, Géraldine; Rémy, Chantal; Laissue, Jean A.; Barbier, Emmanuel L.; Brun, Emmanuel; Serduc, Raphaël

2013-01-01

Purpose: Synchrotron microbeam radiation therapy (MRT) is an innovative irradiation modality based on spatial fractionation of a high-dose X-ray beam into lattices of microbeams. The increase in lifespan of brain tumor-bearing rats is associated with vascular damage but the physiological consequences of MRT on blood vessels have not been described. In this manuscript, we evaluate the oxygenation changes induced by MRT in an intracerebral 9L gliosarcoma model. Methods: Tissue responses to MRT (two orthogonal arrays (2 × 400 Gy)) were studied using magnetic resonance-based measurements of local blood oxygen saturation (MR S O 2 ) and quantitative immunohistology of RECA-1, Type-IV collagen and GLUT-1, marker of hypoxia. Results: In tumors, MR S O 2 decreased by a factor of 2 in tumor between day 8 and day 45 after MRT. This correlated with tumor vascular remodeling, i.e. decrease in vessel density, increases in half-vessel distances (×5) and GLUT-1 immunoreactivity. Conversely, MRT did not change normal brain MR S O 2 , although vessel inter-distances increased slightly. Conclusion: We provide new evidence for the differential effect of MRT on tumor vasculature, an effect that leads to tumor hypoxia. As hypothesized formerly, the vasculature of the normal brain exposed to MRT remains sufficiently perfused to prevent any hypoxia

Forbrugerens sjæl og branding med succes

DEFF Research Database (Denmark)

Hermansen, Judy

2008-01-01

Branding er en slags besjæling af produkter - det er at tage en genstand, som bare er et fysisk, funktionel ting og så få den til at betyde noget for nogen. Det, der karakteriserer brands er netop, at vi føler noget overfor dem. Det kan godt være vi føler afsky - men vi føler noget. Og vi inddrag...

Natural attenuation at a former gas plant site: isotope analyses; Nachweis von Natural Attenuation mittels Isotopenuntersuchungen an einem ehemaligen Kokereistandort

Energy Technology Data Exchange (ETDEWEB)

Nagel, Aglaia; Strauss, Harald; Achten, Christine [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Geologie und Palaeontologie, Muenster (Germany); Stephan, Manuel [Universitaet Duisburg-Essen, Instrumentelle Analytische Chemie, Essen (Germany)

2011-12-15

Natural attenuation of mono- (BTEX) and polycyclic aromatic hydrocarbons (PAHs) was studied in groundwater at a former gas plant site over a distance of about 500 m. The contamination source was located within a 4-6 m thick succession of interbedded silt and sand (K{sub f} =1,4 .10{sup -7} m/s) at a depth of about 5-6 m below the surface. Groundwater flow times between source and the receiving surface waters were determined on the order of a few hundred years. The main contaminants were found to be benzene and naphthalene with concentrations up to 200,000 and 8,500 {mu}g/l, respectively. Over the past 9 years, concentrations within the contaminant plume have decreased and degradation of benzene was proven by compound specific carbon isotope analyses. In addition, sulphur isotope studies revealed that sulphate reduction has played a significant role. This was supported by ambient sulphate concentrations of 300-1,800 {mu}g/l at the site that are sufficient to sustain a long-term perspective for this process. In agreement with these physico-chemical conditions, no transfer of BTEX or PAHs from the plume into the nearby river has been observed. (orig.) [German] An einem ehemaligen Kokereistandort im Ruhrgebiet wurde das Potenzial von Natural Attenuation (natuerlicher Abbau und Rueckhalt) fuer mono- (BTEX) und polyzyklische aromatische Kohlenwasserstoffe (PAK) im Grundwasser auf einer Fliessstrecke von ca. 500 m untersucht. Das Schadenszentrum befindet sich unter eingeebnetem Bergematerial in ca. 5-6 m Tiefe unter Gelaendeoberkante innerhalb einer ca. 4-6 m maechtigen Schluff-Sand-Wechselfolge (K{sub f} =1,4 .10{sup -7} m/s). Im gesamten Aquifer resultieren Fliesszeiten von wenigen Hundert Jahren vom Schadstoffzentrum bis zur Vorflut. Hauptkontaminanten sind Benzen (bis ca. 200.000 {mu}g/l) und Naphthalen (bis ca. 8.500 {mu}g/l). An der Fahnenspitze liegen seit 9 Jahren schrumpfende Konzentrationen vor, die in Einklang mit einem mittels Kohlenstoffisotopie

AcEST: DK952163 [AcEST

Lifescience Database Archive (English)

Full Text Available - Swiss-Prot (release 56.9) Link to BlastX Result : Swiss-Prot sp_hit_id A4FV84 Definition sp|A4FV84|MRT4_BOVIN mRNA turnover...............................done Score E Sequences producing significant alignments: (bits) Value sp|A4FV84|MRT4_BOVIN mRNA turnover... protein 4 homolog OS=Bos taur... 147 3e-35 sp|Q9D0I8|MRT4_MOUSE mRNA turnover prote...in 4 homolog OS=Mus musc... 147 4e-35 sp|Q9UKD2|MRT4_HUMAN mRNA turnover protein ...4 homolog OS=Homo sap... 145 1e-34 sp|Q86HD3|MRT4_DICDI mRNA turnover protein 4 homolog OS=Dictyost... 135 2

The effect of urban geometry on mean radiant temperature under future climate change: a study of three European cities.

Science.gov (United States)

Lau, Kevin Ka-Lun; Lindberg, Fredrik; Rayner, David; Thorsson, Sofia

2015-07-01

Future anthropogenic climate change is likely to increase the air temperature (T(a)) across Europe and increase the frequency, duration and magnitude of severe heat stress events. Heat stress events are generally associated with clear-sky conditions and high T(a), which give rise to high radiant heat load, i.e. mean radiant temperature (T(mrt)). In urban environments, T mrt is strongly influenced by urban geometry. The present study examines the effect of urban geometry on daytime heat stress in three European cities (Gothenburg in Sweden, Frankfurt in Germany and Porto in Portugal) under present and future climates, using T(mrt) as an indicator of heat stress. It is found that severe heat stress occurs in all three cities. Similar maximum daytime T(mrt) is found in open areas in all three cities despite of the latitudinal differences in average daytime T(mrt). In contrast, dense urban structures like narrow street canyons are able to mitigate heat stress in the summer, without causing substantial changes in T(mrt) in the winter. Although the T(mrt) averages are similar for the north-south and east-west street canyons in each city, the number of hours when T(mrt) exceeds the threshold values of 55.5 and 59.4 °C-used as indicators of moderate and severe heat stress-in the north-south canyons is much higher than that in the east-west canyons. Using statistically downscaled data from a regional climate model, it is found that the study sites were generally warmer in the future scenario, especially Porto, which would further exacerbate heat stress in urban areas. However, a decrease in solar radiation in Gothenburg and Frankfurt reduces T(mrt) in the spring, while the reduction in T(mrt) is somewhat offset by increasing T(a) in other seasons. It suggests that changes in the T(mrt) under the future scenario are dominated by variations in T(a). Nonetheless, the intra-urban differences remain relatively stable in the future. These findings suggest that dense urban

Dynamic contrast-enhanced MRI for automatic detection of foci @]@of residual or recurrent disease after prostatectomy

Energy Technology Data Exchange (ETDEWEB)

Parra, N.A.; Orman, Amber; Abramowitz, Matthew; Pollack, Alan; Stoyanova, Radka [University of Miami Miller School of Medicine, Department of Radiation Oncology, Miami, FL (United States); Padgett, Kyle [University of Miami Miller School of Medicine, Department of Radiation Oncology, Miami, FL (United States); University of Miami Miller School of Medicine, Department of Radiology, Miami, FL (United States); Casillas, Victor [University of Miami Miller School of Medicine, Department of Radiology, Miami, FL (United States); Punnen, Sanoj [University of Miami Miller School of Medicine, Department of Urology, Miami, FL (United States)

2017-01-15

This study aimed to develop an automated procedure for identifying suspicious foci of residual/recurrent disease in the prostate bed using dynamic contrast-enhanced-MRI (DCE-MRI) in prostate cancer patients after prostatectomy. Data of 22 patients presenting for salvage radiotherapy (RT) with an identified gross tumor volume (GTV) in the prostate bed were analyzed retrospectively. An unsupervised pattern recognition method was used to analyze DCE-MRI curves from the prostate bed. Data were represented as a product of a number of signal-vs.-time patterns and their weights. The temporal pattern, characterized by fast wash-in and gradual wash-out, was considered the ''tumor'' pattern. The corresponding weights were thresholded based on the number (1, 1.5, 2, 2.5) of standard deviations away from the mean, denoted as DCE1.0,.., DCE2.5, and displayed on the T2-weighted MRI. The resultant four volumes were compared with the GTV and maximum pre-RT prostate-specific antigen (PSA) level. Pharmacokinetic modeling was also carried out. Principal component analysis determined 2-4 significant patterns in patients' DCE-MRI. Analysis and display of the identified suspicious foci was performed in commercial software (MIM Corporation, Cleveland, OH, USA). In general, DCE1.0/DCE1.5 highlighted larger areas than GTV. DCE2.0 and GTV were significantly correlated (r = 0.60, p < 0.05). DCE2.0/DCA2.5 were also significantly correlated with PSA (r = 0.52, 0.67, p < 0.05). K{sup trans} for DCE2.5 was statistically higher than the GTV's K{sup trans} (p < 0.05), indicating that the automatic volume better captures areas of malignancy. A software tool was developed for identification and visualization of the suspicious foci in DCE-MRI from post-prostatectomy patients and was integrated into the treatment planning system. (orig.) [German] Entwicklung eines automatischen Analyseverfahrens, um nach Prostatektomie mittels dynamischer kontrastmittelverstaerkter

Adaptive transmission schemes for MISO spectrum sharing systems: Tradeoffs and performance analysis

KAUST Repository

Bouida, Zied

2014-10-01

In this paper, we propose a number of adaptive transmission techniques in order to improve the performance of the secondary link in a spectrum sharing system. We first introduce the concept of minimum-selection maximum ratio transmission (MS-MRT) as an adaptive variation of the existing MRT (MRT) technique. While in MRT all available antennas are used for transmission, MS-MRT uses the minimum subset of antennas verifying both the interference constraint (IC) to the primary user and the bit error rate (BER) requirements. Similar to MRT, MS-MRT assumes that perfect channel state information (CSI) is available at the secondary transmitter (ST), which makes this scheme challenging from a practical point of view. To overcome this challenge, we propose another transmission technique based on orthogonal space-time block codes with transmit antenna selection (TAS). This technique uses the full-rate full-diversity Alamouti scheme in order to maximize the secondary\\'s transmission rate. The performance of these techniques is analyzed in terms of the average spectral efficiency (ASE), average number of transmit antennas, average delay, average BER, and outage performance. In order to give the motivation behind these analytical results, the tradeoffs offered by the proposed schemes are summarized and then demonstrated through several numerical examples.

Comparative Evaluation of Partial α2 -Adrenoceptor Agonist and Pure α2 -Adrenoceptor Antagonist on the Behavioural Symptoms of Withdrawal after Chronic Alcohol Administration in Mice.

Science.gov (United States)

Arora, Shivani; Vohora, Divya

2016-08-01

As an addictive drug, alcohol produces withdrawal symptoms if discontinued abruptly after chronic use. Clonidine (CLN), a partial α2 -adrenergic agonist, and mirtazapine (MRT), an antagonist of α2 -adrenoceptor, both clinically aid alcohol withdrawal. Considering different mechanisms of action of the two drugs, this study was designed to see how far these two mechanistically different drugs differ in their ability to decrease the severity of ethanol withdrawal syndrome. The effect of CLN and MRT on ethanol withdrawal-induced anxiety, depression and memory impairment was analysed using EPM, FST and PAR tests, respectively. Animals received distilled water, ethanol and/or either of the drugs (CLN and MRT) in different doses. Relapse to alcohol use was analysed by CPP test. Animals received ethanol as a conditioning drug and distilled water, CLN or MRT as test drug. CLN and MRT both alleviated anxiety in a dose-dependent manner. MRT (4 mg/kg) was more effective than CLN (0.1 mg/kg) in ameliorating the anxiogenic effect of alcohol withdrawal. However, CLN treatment increased depression. It significantly decreased swimming time and increased immobility time, whereas MRT treatment decreased immobility time and increased climbing and swimming time during abstinence. The effect was dose dependent for both drugs. The results of PAR test show that CLN treatment worsens working memory. Significant increase in SDE and TSZ and decrease in SDL were observed in CLN-treated animals. MRT treatment, on the other hand, improved working memory at both doses. Further, both CLN and MRT alleviated craving. A significant decrease in time spent in the ethanol-paired chamber was seen. MRT treatment at both doses showed better effect than CLN in preventing the development of preference in CPP test. These findings indicate a potential therapeutic use and better profile of mirtazapine over clonidine in improving memory, as well as in alleviating depression, anxiety and craving associated

The Impacts of the Mass Rapid Transit System on Household Car Ownership in Taipei

Directory of Open Access Journals (Sweden)

Wen-Hsiu Huang

2014-06-01

Full Text Available This paper investigates the impacts of Taipei Mass Rapid Transit (MRT system on household car ownership and analyses how socioeconomic characteristics affect household car ownership. We employ a difference-in-difference (DID strategy integrated with generalized Poisson regression models to examine the effects of MRT. The results are as follows: first, the establishment of Taipei MRT significantly reduced the level of household car ownership. Expanding the network of MRT system can be a feasible policy to control car ownership. Second, the levels of household car ownership are related to household’s socioeconomic characteristics. Third, households with high dependence on public transport own fewer cars after Taipei MRT began operation. Hence, the traffic authority should adopt more effective methods to encourage public transit use in order to decrease household car ownership.

Investigations on the effects of ``Ecstasy`` on cerebral glucose metabolism: an 18-FDG PET study; Untersuchungen zum Einfluss von ``Ecstasy`` auf den zerebralen Glukosemetabolismus: eine 18-FDG-PET-Studie

Energy Technology Data Exchange (ETDEWEB)

Schreckenberger, M.; Sabri, O.; Arning, C.; Tuttass, T.; Schulz, G.; Kaiser, H.J.; Wagenknecht, G.; Buell, U. [Klinik fuer Nuklearmedizin, Universitaetsklinik, RWTH Aachen (Germany); Gouzoulis-Mayfrank, E.; Sass, H. [Klinik fuer Psychiatrie, Universitaetsklinikum, RWTH Aachen (Germany)

1998-12-31

Doppelblindstudie wurden 16 gesunde Probanden ohne Drogenanamnese mittels 18-FDG-PET 110-120 min nach oraler Verabreichung von 2 mg/kg KG MDE (n=8) oder Placebo (n=8) untersucht. Zwei Minuten vor Injektion des Radiopharmazeutikums startend erfolgte ueber insgesamt 32 min eine konstante kognitive Stimulation ueber ein Wortrepetitionsparadigma, um konstante und vergleichbare mentale Bedingungen waehrend der zerebralen 18-FDG-Aufnahme zu gewaehrleisten. Die Darstellung der Individualanatomie erfolgte anhand T1-gewichteter 3D-flash MRT mit anschliessender manueller Regionalisierung in 108 Regions-of-Interest und PET/MRT Overlay. Absolute Quantifizierung der rMRGlu sowie Normierung auf den Globalmetabolismus mit anschliessendem Vergleich MDE versus Placebo mittels U-Test nach Mann und Whitney. Ergebnisse: Gegenueber der Placebo-Gruppe fand sich unter MDE keine signifikante Aenderung der globalen MRGlu (MDE: 41,8{+-}11,1 {mu}mol/min/100 g, Placebo: 50,1{+-}18,1 {mu}mol/min/100 g, p=0,298). Die normierten metabolischen Daten zeigten eine signifikante Minderung der rMRGlu im beidseitigen Frontalkortex: Links frontal posterior (-7,1%, p<0,05) und rechts praefrontal superior (-4,6%, p<0,05). Signifikante Steigerungen der rMRGlu fanden sich dagegen im beidseitigen Zerebellum (rechts: +10,1%, p<0,01; links: +7,6%, p<0,05) sowie im rechten Putamen (+6,2%, p<0,05). Schlussfolgerung: In der vorliegenden Studie konnten unter dem Akuteinfluss des `Ecstasy`-Analogons MDE neurometabolische Veraenderungen im Sinne einer fronto-striato-cerebellaeren Dysbalance nachgewiesen werden, die parallelen zu sowohl anderen psychotropen Substanzen als auch verschiedenen endogenen Psychosen aufweisen. (orig.)

An ICMP-Based Mobility Management Approach Suitable for Protocol Deployment Limitation

Directory of Open Access Journals (Sweden)

Jeng-Yueng Chen

2009-01-01

Full Text Available Mobility management is one of the important tasks on wireless networks. Many approaches have been proposed in the past, but none of them have been widely deployed so far. Mobile IP (MIP and Route Optimization (ROMIP, respectively, suffer from triangular routing problem and binding cache supporting upon each node on the entire Internet. One step toward a solution is the Mobile Routing Table (MRT, which enables edge routers to take over address binding. However, this approach demands that all the edge routers on the Internet support MRT, resulting in protocol deployment difficulties. To address this problem and to offset the limitation of the original MRT approach, we propose two different schemes, an ICMP echo scheme and an ICMP destination-unreachable scheme. These two schemes work with the MRT to efficiently find MRT-enabled routers that greatly reduce the number of triangular routes. In this paper, we analyze and compare the standard MIP and the proposed approaches. Simulation results have shown that the proposed approaches reduce transmission delay, with only a few routers supporting MRT.

Malignant rhabdoid tumor of the liver: a case report and literature review

Directory of Open Access Journals (Sweden)

Satoru Oita

2015-03-01

Full Text Available Malignant rhabdoid tumor (MRT is a rare and aggressive malignancy associated with poor outcomes. MRT of the liver is even rarer, and little information has been described. We report the case of an 8-month-old boy with MRT of the liver. The tumor showed aggressive progression despite a multidisciplinary approach, and the patient died due to multiple organ failure 14 days after admission. Autopsy revealed the liver tumor and multiple metastases with negative immunohistochemistry for INI1/BAF47. A review of 53 cases of pediatric MRT of the liver is provided.

Praeoperativ funktionel magnetisk resonans-billeddannelse hos patienter med hjernetumor

DEFF Research Database (Denmark)

Laustsen, Søren Ravn; Sørensen, Preben; Fründ, Torben

2010-01-01

to fMRI activation was measured using GE-reformat version 4.2 after raw data had been postprocessed using GE BrainwavePA version 1.3.08130. The neurosurgeons valuation of fMRI in the preoperative decision-making process was obtained using a standard questionnaire. RESULTS: There was a trend...

Praeoperativ funktionel magnetisk resonans-billeddannelse hos patienter med hjernetumor

DEFF Research Database (Denmark)

Laustsen, Søren Ravn; Meulengracht Sørensen, Preben; Fründ, Torben

2010-01-01

INTRODUCTION: Functional Magnetic Resonance Imaging (fMRI) allows important functions in the brain cortex to be mapped noninvasively. The purpose with this work was to investigate a possible correlation between the distance from the tumour margin to fMRI activity and postoperative neurological...... deficits by means of a standardised method for measurement of distance. A second purpose was to investigate the influence of preoperative fMRI on the neurosurgical decision-making process. MATERIAL AND METHODS: Retrospective study of 25 patients. The inclusion criteria were surgery or biopsy after f......MRI plus a three-month postoperative assessment. A total of 14 patients complied with these requirements (six men and eight women, the mean age was 39 years). fMRI raw data was collected using a three tesla magnetic resonance scanner (Signa HDx R14M5, GE Healthcare). The distance from the tumour margin...

Praeoperativ funktionel magnetisk resonans-billeddannelse hos patienter med hjernetumor

DEFF Research Database (Denmark)

Laustsen, Søren Ravn; Meulengracht Sørensen, Preben; Fründ, Torben

2010-01-01

MRI plus a three-month postoperative assessment. A total of 14 patients complied with these requirements (six men and eight women, the mean age was 39 years). fMRI raw data was collected using a three tesla magnetic resonance scanner (Signa HDx R14M5, GE Healthcare). The distance from the tumour margin...... to fMRI activation was measured using GE-reformat version 4.2 after raw data had been postprocessed using GE BrainwavePA version 1.3.08130. The neurosurgeons valuation of fMRI in the preoperative decision-making process was obtained using a standard questionnaire. RESULTS: There was a trend...... of association between distance from tumour to eloquent functional areas and the patients' postoperative neurological outcome (Fisher's exact test: distance operate or not (42%), when deciding the surgical approach...

Praeoperativ funktionel magnetisk resonans-billeddannelse hos patienter med hjernetumor

DEFF Research Database (Denmark)

Laustsen, Søren Ravn; Sørensen, Preben; Fründ, Torben

2010-01-01

MRI plus a three-month postoperative assessment. A total of 14 patients complied with these requirements (six men and eight women, the mean age was 39 years). fMRI raw data was collected using a three tesla magnetic resonance scanner (Signa HDx R14M5, GE Healthcare). The distance from the tumour margin...

The role of positron-emission-tomography (F-18-FDG-PET) in the staging and follow-up of lung cancer and in the evaluation of focal pulmonary abnormalities; Positronenemissionstomographie (PET) mit F-18-FDG in der Diagnostik des Bronchialkarzinoms und zur Dignitaetsabklaerung von pulmonalen Raumforderungen

Energy Technology Data Exchange (ETDEWEB)

Baum, R.P. [Zentralklinik Bad Berka (Germany). Klinik fuer Nuklearmedizin/PET-Zentrum; Bonnet, R.B. [Zentralklinik Bad Berka (Germany). Klinik fuer Pneumologie; Presselt, N. [Zentralklinik Bad Berka (Germany). Klinik fuer Thorax- und Gefaesschirurgie; Leonhardi, J. [Zentralklinik Bad Berka (Germany). Inst. fuer Bildgebende Diagnostik

2001-04-01

bronchial carcinomas (except for slowly growing neuroendocrine tumors like carcinoids which show rarely an increased FDG metabolism). The specificity of FDG-PET is in the range of >80%. (orig.) [German] Prospektive Studien zeigten im Direktvergleich von PET und Spiral-CT eine deutlich hoehere diagnostische Genauigkeit der PET im Lymphknotenstaging des Bronchialkarzinoms (insbesondere mediastinal, d.h. N2- oder N3-Befall). Mittels FDG-PET koennen auch normal grosse Lymphknoten (im CT<10 mm) als tumorbefallen charakterisiert werden (Upstaging). Andererseits kann die PET aufgrund der hoeheren Spezifitaet eine Metastasierung in computertomographisch vergroesserten Lymphknoten oftmals ausschliessen (Downstaging in bis zu 30% der untersuchten Patienten). Eine Aenderung des therapeutischen Prozedere durch die PET-Untersuchung ergab sich bei bis zu 30% aller Patienten und unter Einschluss der Fernmetastasen bei ueber 40% der untersuchten Patienten. Nebennierenmetastasen (Sensitivitaet 100%, Spezifitaet 80%), als auch Leber-, Knochen- und parenchymatoese Lungenmetastasen und abdominelle und zervikale Lymphknotenmetastasen werden mit hoher Sensitivitaet und Spezifitaet detektiert. Bei zerebralen Metastasen ist die MRT im Nachweis eindeutig ueberlegen, bei sehr kleinen Lungenlaesionen (<5 mm) ist die Spiral-CT sensitiver. Der Nachweis des lokalen Rezidivs eines zuvor operierten Lungenkarzinoms ist mit einer Sensitivitaet von 83-100% (Mittel 95%) und einer Spezifitaet von 62-100% (Mittel 81%) moeglich. Auch zur Therapiekontrolle ist die FDG-PET geeignet, da die Abnahme des Glukosemetabolismus mit dem Therapieerfolg korreliert. Problematisch sind inflammatorische Veraenderungen in den ersten Wochen nach Strahlentherapie ('Strahlenpneumonitis'), die ebenfalls zu einem gesteigerten Glukosemetabolismus fuehren koennen, weshalb ein groesserer Zeitabstand (mehrere Wochen bis Monate) nach Strahlentherapie sinnvoll ist. Die FDG-PET hat sich in der Differenzialdiagnostik von

Interest of synchrotron radiation for the therapy of brain tumors: methodology and preclinical applications

International Nuclear Information System (INIS)

Regnard, P.

2007-12-01

Microbeam radiation (M.R.T.) and stereotactic synchrotron radiation therapy (S.S.R.T.) are innovative techniques currently developed at the european Synchrotron radiation facility. these techniques led to promising, but rarely reproduced, results. the use of different tumoral models for each techniques limit comparisons. M.R.T. experiments on rats bearing 9L tumors 14 days after implantation displayed a double median survival time ( from 20 to 40 days) with a 200 μm spacing irradiation, while a 100 μm spacing irradiation tripled this median (67 days) but damaged normal tissue. the impact of the device dividing synchrotron beam into micro-beams, named multi sit collimator, was also demonstrated. combination of drugs with M.R.T. irradiation was tested. promising results (median survival time: 40 days and 30% of long term survivors) were obtained with an intratumoral injection of gadolinium coupled with a crossing M.R.T. irradiation at 460 Gy. Moreover, earlier M.R.T. irradiation (tumor at D10) quadrupled the median survival time (79 days) with 30% of long term survivors. A new imaging device to target the tumor before irradiation and an adapted collimator will increase the M.R.T. results. As the differences existing between tumoral models used in M.R.T. (9L models) and in S.S.R.T. (F98 models) are major, M.R.T./S.S.R.T. comparative experiments were realised on these two models. Results showed that the two techniques have the same efficacy on F98 model and that the M.R.T. is more effective on 9L model. This can help to define adapted tumor type for these techniques. (author)

Interest of synchrotron radiation for the therapy of brain tumors: methodology and preclinical applications; Interet du rayonnement synchrotron dans la therapie des tumeurs cerebrales: methodologie et applications precliniques

Energy Technology Data Exchange (ETDEWEB)

Regnard, P

2007-12-15

Microbeam radiation (M.R.T.) and stereotactic synchrotron radiation therapy (S.S.R.T.) are innovative techniques currently developed at the european Synchrotron radiation facility. these techniques led to promising, but rarely reproduced, results. the use of different tumoral models for each techniques limit comparisons. M.R.T. experiments on rats bearing 9L tumors 14 days after implantation displayed a double median survival time ( from 20 to 40 days) with a 200 {mu}m spacing irradiation, while a 100 {mu}m spacing irradiation tripled this median (67 days) but damaged normal tissue. the impact of the device dividing synchrotron beam into micro-beams, named multi sit collimator, was also demonstrated. combination of drugs with M.R.T. irradiation was tested. promising results (median survival time: 40 days and 30% of long term survivors) were obtained with an intratumoral injection of gadolinium coupled with a crossing M.R.T. irradiation at 460 Gy. Moreover, earlier M.R.T. irradiation (tumor at D10) quadrupled the median survival time (79 days) with 30% of long term survivors. A new imaging device to target the tumor before irradiation and an adapted collimator will increase the M.R.T. results. As the differences existing between tumoral models used in M.R.T. (9L models) and in S.S.R.T. (F98 models) are major, M.R.T./S.S.R.T. comparative experiments were realised on these two models. Results showed that the two techniques have the same efficacy on F98 model and that the M.R.T. is more effective on 9L model. This can help to define adapted tumor type for these techniques. (author)

Three-dimensional simulations of Bingham plastic flows with the multiple-relaxation-time lattice Boltzmann model

Directory of Open Access Journals (Sweden)

Song-Gui Chen

2016-01-01

Full Text Available This paper presents a three-dimensional (3D parallel multiple-relaxation-time lattice Boltzmann model (MRT-LBM for Bingham plastics which overcomes numerical instabilities in the simulation of non-Newtonian fluids for the Bhatnagar–Gross–Krook (BGK model. The MRT-LBM and several related mathematical models are briefly described. Papanastasiou’s modified model is incorporated for better numerical stability. The impact of the relaxation parameters of the model is studied in detail. The MRT-LBM is then validated through a benchmark problem: a 3D steady Poiseuille flow. The results from the numerical simulations are consistent with those derived analytically which indicates that the MRT-LBM effectively simulates Bingham fluids but with better stability. A parallel MRT-LBM framework is introduced, and the parallel efficiency is tested through a simple case. The MRT-LBM is shown to be appropriate for parallel implementation and to have high efficiency. Finally, a Bingham fluid flowing past a square-based prism with a fixed sphere is simulated. It is found the drag coefficient is a function of both Reynolds number (Re and Bingham number (Bn. These results reveal the flow behavior of Bingham plastics.

Prediction of the pharmacological effect of octreotide in acromegaly by means of {sup 111}In-pentetreotide scintigraphy and calculation of a pituitary uptake index; Praediktion der pharmakologischen Wirkung von Octreotid bei Akromegalie mittels {sup 111}In-Pentetreotid-Szintigraphie und Berechnung eines hypophysaeren Uptake-Index

Energy Technology Data Exchange (ETDEWEB)

Goerges, R. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Cordes, U. [Arbeitsgemeinschaft Niedergelassener Endokrinologen, Mainz/Darmstadt (Germany); Engelbach, M. [Mainz Univ. (Germany). III. Medizinische Klinik und Poliklinik; Bartelt, K.M. [Arbeitsgemeinschaft Niedergelassener Endokrinologen, Mainz/Darmstadt (Germany); Haberern, G. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Hey, O. [Mainz Univ. (Germany). Neurochirurgische Klinik und Poliklinik; Beyer, J. [Mainz Univ. (Germany). III. Medizinische Klinik und Poliklinik; Bockisch, A. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

1997-06-01

Aim: The aim of our prospective study was to optimize the determination of the pituitary somatostatin receptor status by means of 111-In-pentetreotide scintigraphy and to compare it intraindividually with the pharmacological effect of octreotide in active acromegaly. Methods: In n=22 patients with growth hormone (GH) secreting pituitary adenoma, 111-In-penetreotide scintigraphy was performed, and the specific radionuclide accumulation in the pituitary area (evaluation visually as well as semiquantitatively by means of ROI technique and calculation of various uptake indices) was correlated with the acute drop of GH after administration of 100 {mu}g octreotide s.c. (octreotide acute test). Results: The uptake index we propose (cts/pixel-ratio circular pituitary ROI: Irregular cerebrum ROI after background correction in the sagittal SPECT slice with maximum pituitary uptake 24 h p.i.) correlates best with the pharmacological effect (acute decrease of GH levels) of octreotide; its upper normal limit amounts of 3.5. Conclusion: As often the normal pituitary gland can be visualized scintigraphically, the purely visual differentiation between a normal and pathological receptor status sometimes is equivocal. A pituitary uptake index, calculated by means of a standardized ROI technique, facilitates this discrimination and so contributes to select possible responders for a treatment with octreotide. (orig.) [Deutsch] Ziel: Ziel unserer prospektiven Studie war die optimierte Bestimmung des hypophysaeren Somatostatin-Rezeptorstatus in der 111-In-Pentetreotid-Szintigraphie und der intraindividuelle Vergleich mit dem pharmakologischen Effekt von Octreotid bei florider Akromegalie. Methoden: Bei n=22 Patienten mit Wachstumshormon-(GH)-sezernierendem Hypophysenadenom wurde eine 111-In-Pentetreotid-Szintigraphie durchgefuehrt und die spezifische Nuklidakkumulation in der Hypophysenregion (Auswertung sowohl visuell als auch semiquantitativ mittels ROI-Technik und Berechnung

Die transkranielle Doppler-Sonographie zur Identifikation von Rechts-Links-Shunts

OpenAIRE

Jekentaite, R. (Ruta)

2003-01-01

Paradoxe Embolien über einen Rechts-Links-Shunt (RLS) stellen eine Ursache von Hirninfarkten dar. Diese Shunts werden mittels TEE oder TCD diagnostiziert. Ziele dieser Studie waren die Bestimmung des optimalen Timings des Valsalva-Manövers (VM) sowie Vergleich der zwei Kontrastmittel Echovist®-300 und Echovist®-200. 64 Patienten wurden mittels beider Methoden untersucht. Nach der KM-Injektion wurden die Mikroemboliesignale (MES) in der ACM bilateral dopplersonographisch registriert. Die Unt...

Metal Separations and Recovery in the Mining Industry

Science.gov (United States)

Izatt, Steven R.; Bruening, Ronald L.; Izatt, Neil E.

2012-11-01

Molecular Recognition Technology (MRT) plays an important role in the hydrometallurgical processing dissolved entities in solutions in the mining industry. The status of this industry with respect to sustainability and environmental issues is presented and discussed. The roles of MRT and ion exchange in metal separation and recovery processes in the mining industry are discussed and evaluated. Examples of MRT separation processes of interest to the mining community are given involving gold, cobalt purification by extraction of trace cadmium, rhenium, and platinum group metals (PGMs). MRT processes are shown to be sustainable, economically viable, energy efficient, and environmentally friendly, and to have a low carbon footprint.

Theoretical and Experimental Studies of Magneto-Rayleigh-Taylor Instabilities

International Nuclear Information System (INIS)

Lau, Yue Ying; Gilgenbach, Ronald

2013-01-01

Magneto-Rayleigh-Taylor instability (MRT) is important to magnetized target fusion, wire-array z-pinches, and equation-of-state studies using flyer plates or isentropic compression. It is also important to the study of the crab nebula. The investigators performed MRT experiments on thin foils, driven by the mega-ampere linear transformer driver (LTD) facility completed in their laboratory. This is the first 1-MA LTD in the USA. Initial experiments on the seeding of MRT were performed. Also completed was an analytic study of MRT for a finite plasma slab with arbitrary magnetic fields tangential to the interfaces. The effects of magnetic shear and feedthrough were analyzed

Theoretical and Experimental Studies of Magneto-Rayleigh-Taylor Instabilities

Energy Technology Data Exchange (ETDEWEB)

Lau, Yue Ying [University of Michigan, Ann Arbor, MI (United States); Gilgenbach, Ronald [University of Michigan, Ann Arbor, MI (United States)

2013-07-07

Magneto-Rayleigh-Taylor instability (MRT) is important to magnetized target fusion, wire-array z-pinches, and equation-of-state studies using flyer plates or isentropic compression. It is also important to the study of the crab nebula. The investigators performed MRT experiments on thin foils, driven by the mega-ampere linear transformer driver (LTD) facility completed in their laboratory. This is the first 1-MA LTD in the USA. Initial experiments on the seeding of MRT were performed. Also completed was an analytic study of MRT for a finite plasma slab with arbitrary magnetic fields tangential to the interfaces. The effects of magnetic shear and feedthrough were analyzed.

Indirect MR venography: contrast medium protocols, postprocessing and combination in diagnosing pulmonary emboli with MRI; Indirekte MR-Phlebografie: Kontrastmittelprotokolle, Nachverarbeitung und Kombination mit Lungenemboliediagnostik in der MRT

Energy Technology Data Exchange (ETDEWEB)

Kluge, A.; Bachmann, G. [Diagnostische Radiologie, Kerckhoff-Klinik, Bad Nauheim (Germany); Rominger, M. [Diagnostische Radiologie, Phillips-Univ. Marburg (Germany); Schoenburg, M. [Herzchirurgie, Kerckhoff-Klinik, Bad Nauheim (Germany)

2004-07-01

Purpose: Integration of MR venography in a comprehensive MR imaging protocol in patients with suspected pulmonary embolism (PE) and evaluation of contrast media dosage, timing and postprocessing for diagnostic accuracy. Materials and Methods: Fortyeight consecutive inpatients with suspected PE or deep vein thrombosis were examined by MR venography according to one of the following protocols: protocol I: MR venography only, 0.25 mmol/kg bodyweight (BW) Gadopentate dimeglumine(Gd-DTPA) as single dose, bolus timing; protocol II: MR angiography of pulmonary arteries with a cumulative dosage of 0.25 mmol/kg contrast media, modification of coil setting for MR venography without further contrast media application; protocol III: as protocol II but with 0.125 mmol/kg BW, followed by MR venography. Signal-to-noise ratio, contrast-to-noise ratio, number of definable vascular segments and image quality were evaluated. The results were compared to conventional bilateral venography. Results: All MR venography examinations were of diagnostic quality and the examination time was below 10 min. MR venography could be performed in all 48 patients comparted to 43 of 48 patients for conventional venography. Significantly more superficial and deep veins of the leg could be visualized by MR venography (94% compared to 83% for conventional venography). Sensitivity and specificity were 100% and 92%, respectively. Quality differed significantly between 0.125 mmol/kg (protocol III) and 0.25 mmol/kg Gd-DTPA (protocols I and II) while timing did not influence quality (protocol I vs. II). (orig.) [German] Ziel: Integration der MR-Phlebografie in ein umfassendes Konzept der MRT-Diagnostik bei Verdacht auf Lungenembolie (LE). Untersuchung des Einflusses von Kontrastmittelmenge, -bolusform und Verzoegerungszeit sowie der Nachverarbeitung auf die diagnostische Qualitaet von MR-Phlebografien. Material und Methode: Bei 48 konsekutiven stationaeren Patienten mit Verdacht auf Beinvenenthrombose (TVT

MRI for therapy control in patients with tetralogy of Fallot; MRT zur Therapiekontrolle bei Patienten mit Fallot-Tetralogie

Energy Technology Data Exchange (ETDEWEB)

Theisen, D.; Reiser, M.F. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Dalla Pozza, R.D. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Abteilung fuer Kinderkardiologie und Paediatrische Intensivmedizin, Kinderherzzentrum, Muenchen (Germany); Malec, E. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Herzchirurgische Klinik, Kinderherzzentrum, Muenchen (Germany)

2011-01-15

With prevalences ranging from 0.26 to 0.8 permille of all live births tetralogy of Fallot (TOF) is the most common congenital heart disease with primary cyanosis. Due to improvements in surgical techniques, nearly all patients can nowadays expect to reach adulthood. After surgical repair, pulmonary regurgitation (PR) occurs in almost every child and is an important contributing factor in long-term morbidity and mortality. Cardiac magnetic resonance imaging is well established for functional assessment and flow measurements and is an ideal tool for serial post-surgical follow-up examinations, as it is non-invasive and does not expose patients to ionizing radiation. The timing of pulmonary valve replacement is crucial as right ventricular (RV) volumes have only proven to normalize when preoperative end-diastolic volumes are <170 ml/m{sup 2} and end-systolic volumes are <85 ml/m{sup 2}. After surgical repair up to 15% of patients have residual or recurrent pulmonary artery stenosis. Distal pulmonary branch stenosis can aggravate PR and lead to right heart failure due to combined pressure and volume overload. Therefore, it has to be diagnosed in time and treated by angioplasty with or without stenting. (orig.) [German] Die Fallot-Tetralogie (TOF) ist mit einer Praevalenz zwischen 0,26 und 0,8 permille aller Lebendgeburten der haeufigste Herzfehler mit primaerer Zyanose. Durch verbesserte Operationstechniken erreichen heute nahezu alle Patienten das Erwachsenenalter. Bei fast allen Patienten tritt eine postoperative Pulmonalinsuffizienz (PI) auf, die entscheidenden Einfluss auf die langfristige Morbiditaet und Mortalitaet hat. Die kardiale Magnetresonanztomographie (MRT) ist fuer Quantifizierung von Ventrikelfunktion und Klappeninsuffizienzen etabliert und aufgrund ihrer fehlenden Invasivitaet und Strahlenexposition sehr gut fuer regelmaessige Verlaufskontrollen der heranwachsenden Patienten geeignet. Insbesondere der Zeitpunkt fuer einen Pulmonalklappenersatz darf

Neural correlates of working memory deficits in schizophrenic patients. Ways to establish neurocognitive endophenotypes of psychiatric disorders; Neuronale Korrelate gestoerter Arbeitsgedaechtnisfunktionen bei schizophrenen Patienten. Ansaetze zur Etablierung neurokognitiver Endophaenotypen psychiatrischer Erkrankungen

Energy Technology Data Exchange (ETDEWEB)

Gruber, O. [Universitaet des Saarlandes, Klinik fuer Psychiatrie und Psychotherapie, Homburg (Saar) (Germany); Max-Planck-Institut fuer Kognitions- und Neurowissenschaften, Leipzig (Germany); Gruber, E.; Falkai, P. [Universitaet des Saarlandes, Klinik fuer Psychiatrie und Psychotherapie, Homburg (Saar) (Germany)

2005-02-01

This article briefly reviews some methodological limitations of functional neuroimaging studies in psychiatric patients. We argue that the investigation of the neural substrates of cognitive deficits in psychiatric disorders requires a combination of functional neuroimaging studies in healthy subjects with corresponding behavioral experiments in patients. In order to exemplify this methodological approach we review recent findings regarding the functional neuroanatomy of distinct components of human working memory and provide evidence for selective dysfunctions of cortical networks that underlie specific working memory deficits in schizophrenia. This identification of subgroups of schizophrenic patients according to neurocognitive parameters may facilitate the establishment of behavioral and neurophysiological endophenotypes and the development of a neurobiological classification of psychiatric disorders. (orig.) [German] Dieser Beitrag befasst sich mit einigen methodischen Problemen funktionell-bildgebender Studien mit psychiatrischen Patienten, aufgrund derer die Untersuchung der neuronalen Korrelate kognitiver Defizite bei psychiatrischen Erkrankungen einer Kombination funktionell-bildgebender Studien bei gesunden Normalprobanden mit Verhaltensuntersuchungen bei Patienten bedarf. Dieser methodische Ansatz wird am Beispiel von Arbeitsgedaechtnisfunktionen erlaeutert, wobei zunaechst neuere Erkenntnisse zur funktionellen Neuroanatomie verschiedener Komponenten des menschlichen Arbeitsgedaechtnisses referiert werden. Anschliessend werden bei schizophrenen Patienten erhobene Befunde vorgestellt, die auf spezifische Stoerungen der funktionellen Integritaet neuronaler Netzwerke mit Arbeitsgedaechtnisfunktionen hinweisen. Die damit verbundene Identifikation von Subgruppen schizophrener Patienten koennte zur Etablierung verhaltensneurophysiologisch definierter Endophaenotypen psychiatrischer Stoerungsbilder fuehren und die Entwicklung einer neurowissenschaftlich

Magnetic resonance imaging in acute intractional tuberculosis; Magnetresonanztomographie bei akuter intrakranieller Tuberkulose

Energy Technology Data Exchange (ETDEWEB)

Venz, S. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Sander, B. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Benndorf, G. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Terstegge, K. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Podrabsky, P. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Cordes, M. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Felix, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany)

1994-12-31

We reported three cases of acute intracranial tuberculosis including miliary tuberculosis, basal meningitis, tuberculomas and neuritis of cranial nerves. All patients had native and contrast enhanced CT and MRI scans. MRI revealed more granulomas and a better imaging contrast in the detection of basal meningitis. Neuritis was diagnosed only with the MRI. MRI scans should be prefered as the imaging procedure in clinically presumed intracranial tuberculosis. (orig.) [Deutsch] Die Befunde von drei Patienten mit intrakranieller Tuberkulose (intrakranielle Miliartuberkulose, Meningitis tuberculosa, Neuritis und Tuberkulome) in der Magnetresonanztomographie (MRT) wurden mit der Computertomographie (CT) verglichen. Sowohl die MRT als auch die CT wurden nativ und nach Kontrastmittelgabe durchgefuehrt. Die MRT zeigte sich im Nachweis von Granulomen insbesondere im Bereich des Hirnstamms ueberlegen. Ebenso wurde ein hoeherer Bildkontrast bei der Darstellung der Meningitis beobachtet. Eine Neuritis der Hirnnerven war nur mit der MRT nachweisbar. Die kontrastmittelunterstuetzte MRT sollte in der bildgebenden Diagnostik einer intrakraniellen Turberkulose primaer zum Einsatz gelangen. (orig.)

Magnetic resonance tomography of the sellar region in patients with endocrine disease

International Nuclear Information System (INIS)

Zenkova, T.S.; Fedina, I.D.; Mel'nichenko, G.A.; Stenina, I.I.; Zubarev, A.V.

1992-01-01

The hypophysis was studied by MR tomography (MRT) in 148 patients with the most prevalent diseases of the hypothalamohypophyseal system and in 13 ones with primary hypothyrosis. The findings evidence a great variety of changes in the MRT picture in the examines. Qualitative and quantitative criteria for MRT diagnosis were suggested. The method was effectively used for a dynamic follow-up of the hypophyseal status in the course of pathogenetic therapy

Osteopathic manual therapy in heart failure patients: A randomized clinical trial.

Science.gov (United States)

Thomaz, Sergio R; Teixeira, Felipe A; de Lima, Alexandra C G B; Cipriano Júnior, Gerson; Formiga, Magno F; Cahalin, Lawrence Patrick

2018-04-01

Heart Failure (HF) patients usually present with increased arterial resistance and reduced blood pressure (BP) leading to an impaired functional capacity. Osteopathic Manual Therapy (OMT) focused on myofascial release techniques (MRT) and in the balancing of diaphragmatic tensions, has been shown to improve blood flow in individuals using the resistive index (RI). However, its effects in HF patients have not been examined. To evaluate the acute response of selected osteopathic techniques on RI, heart rate (HR), and BP in patients with HF. Randomized-controlled clinical trial of HF patients assigned to MRT (six different techniques with three aimed at the pelvis, two at the thorax, and one at the neck for 15 min) or Control group (subjects in supine position for 15 min without intervention). The RI of the femoral, brachial and carotid arteries was measured via doppler ultrasound while HR and BP were measured via sphygmomanometry before and after a single MRT or control intervention. Twenty-two HF patients equally distributed (50% male, mean age 53 years; range 32-69 years) (ejection fraction = 35.6%, VO 2peak : 12.9 mL/kg -1 min -1 ) were evaluated. We found no intra or inter group differences in RI of the carotid (Δ MRT : 0.07% vs Δ Control :11.8%), brachial (Δ MRT :0.17% vs Δ Control : 2.9%), or femoral arteries (Δ MRT :1.65% vs Δ Control : 0.97%) (P > 0.05) and no difference in HR or BP (Δ MRT :0.6% vs Δ Control : 3%), (P > 0.05). A single MRT session did not significantly change the RI, HR, or BP of HF patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cardiac and vascular malformations; Fehlbildungen von Herz und Gefaessen

Energy Technology Data Exchange (ETDEWEB)

Ley, S. [Chirurgische Klinik Dr. Rinecker, Abteilung fuer Diagnostische und Interventionelle Radiologie, Muenchen (Germany); Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Klinische Radiologie, Muenchen (Germany); Ley-Zaporozhan, J. [Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Klinische Radiologie, Abteilung Paediatrische Radiologie, Muenchen (Germany)

2015-07-15

Malformations of the heart and great vessels show a high degree of variation. There are numerous variants and defects with only few clinical manifestations and are only detected by chance, such as a persistent left superior vena cava or a partial anomalous pulmonary venous connection. Other cardiovascular malformations are manifested directly after birth and need prompt mostly surgical interventions. At this point in time echocardiography is the diagnostic modality of choice for morphological and functional characterization of malformations. Additional imaging using computed tomography (CT) or magnetic resonance imaging (MRI) is only required in a minority of cases. If so, the small anatomical structures, the physiological tachycardia and tachypnea are a challenge for imaging modalities and strategies. This review article presents the most frequent vascular, cardiac and complex cardiovascular malformations independent of the first line diagnostic imaging modality. (orig.) [German] Fehlbildungen von Herz und Gefaessen zeigen einen erheblichen Variationsspielraum. Es gibt zahlreiche Varianten und Defekte mit geringer Auspraegung, welche nur per Zufall im Lauf des Lebens detektiert werden; hierzu zaehlen z. B. die persistierende linke obere Hohlvene oder partielle Lungenvenenfehlmuendungen. Andere kardiovaskulaere Fehlbildungen zeigen sich frueh post partum und muessen zeitnah, meist operativ, versorgt werden. Zu diesem Zeitpunkt ist die Echokardiographie ein etabliertes und vollstaendig ausreichendes Verfahren zur morphologischen und funktionellen Charakterisierung. Nur in seltenen Faellen wird eine zusaetzliche Bildgebung mittels CT oder MRT benoetigt. Wenn ja, stellen die kleinen anatomischen Strukturen, die physiologische Tachykardie und Tachypnoe eine besondere Herausforderung fuer die Diagnostik dar. In dieser Uebersicht werden, unabhaengig vom diagnostischen Verfahren, die haeufigsten vaskulaeren, kardialen und komplexen kardiovaskulaeren Malformationen

Molekulargenetische Studie zur Verbreitung und Interaktion von PCV-2 bei Haus- und Wildschweinen

OpenAIRE

Bronnert, Bastian Balthasar Marcel

2014-01-01

Im Rahmen der vorliegenden Arbeit wurden Wild- und Hausschweingewebeproben aus den Jahren 2005 bis 2008 mittels nested PCR auf das Vorkommen von PCV-2 untersucht und die positiv getesteten Proben mittels Realtime PCR quantifiziert. Zusätzlich wurden die Proben im Institut für Pathologie der Justus-Liebig-Universität histologisch und immunhistologisch untersucht (Dissertation Hohloch). Ziel war es das Vorkommen von PCV-2 und die Häufigkeit von PCV-2 assoziierter Erkankungen bei Haus- und Wilds...

Nutrient vessel canals. Differential diagnosis of zystoid carpal lesions on MRI?; Nutritialgefaesskanaele. Magnetresonanztomographische Differentialdiagnose karpaler zystischer Laesionen?

Energy Technology Data Exchange (ETDEWEB)

Vahlensieck, M.; Schild, H.H. [Bonn Univ. (Germany). Radiologische Klinik; Brueser, P. [Malteser Krankenhaus, Bonn (Germany). Hand- und Mikrochirurgische Abt.; Schmidt, H.M. [Bonn Univ. (Germany). Anatomisches Inst.

2000-05-01

mehrere kleine zystische Laesionen im Os lunatum gefunden, umgeben von einem Sklerosesaum. Bei 3 Faellen einer fruehen Lunatummalazie waren unregelmaessige zystische Komponenten von einem diffusen Oedem umgeben. In 7 Faellen mit sehr kleinen zystischen Defekten waren diese subchondral, palmar und dorsal gelegen und entsprachen aufgrund des klinischen Verlaufs und der Lokalisation Nutritialgefaesskanaelen. Schlussfolgerung: Nutritialgefaesskanaele duerfen nicht mit pathologischen zystischen Prozessen des Os lunatums verwechselt werden. Mittels MRT koennen zystische Laesionen im und am Os lunatum weiter spezifiziert werden. Handgelenksganglien weisen typische MR-Zeichen auf. (orig.)

Magnetic resonance angiography and tomography of vertebrobasilar dissections; Magnetresonanzangiographie und Magnetresonanztomographie bei Dissektionen der A. vertebralis

Energy Technology Data Exchange (ETDEWEB)

Felber, S. [Inst. fuer Magnetresonanztomographie und Spektroskopie, Universitaetskliniken Innsbruck (Austria)]|[Universitaetsklinik fuer Radiologie, Klinische Abt. 2, Universitaetskliniken Innsbruck (Austria); Auer, A. [Inst. fuer Magnetresonanztomographie und Spektroskopie, Universitaetskliniken Innsbruck (Austria); Schmidauer, C. [Universitaetsklinik fuer Neurologie, Universitaetskliniken Innsbruck (Austria); Waldenberger, P. [Universitaetsklinik fuer Radiologie, Klinische Abt. 1, Universitaetskliniken Innsbruck (Austria); Aichner, F. [Inst. fuer Magnetresonanztomographie und Spektroskopie, Universitaetskliniken Innsbruck (Austria)

1996-11-01

We retrospectively analyzed the role of MRT and MR angiography (MRA) in the detection of dissections of the vertebral artery. Between 1989 and 1995 we identified 24 patients with a vertebral artery dissection and 1 patient with a basilar artery dissection. The diagnosis of VAD was established by specific arteriographical findings (DSA) or clinical and neuroradiological course. All patients underwent a combined MRT/MRA examination protocol at 1.5 T that consisted of spin-echo imaging and time of flight MRA of the intra- and extracranial arteries using 2D Flash and 3D Fisp sequences. The MRT/MRA findings were correlated to DSA and ultrasound results. During the acute and subacute stage, MRT/MRA revealed abnormal findings in 21 of 22 dissected vessels (95.5%). There was one false-negative MRT/MRA in a patient with a V1 dissection. In 7/22 VAD the MRT/MRA findings were rated specific. DAS was sensitivie in 100% and ultrasound in 77.3%. Specific results were obtained by DSA in 8/22 VAD (36.4%) and in 7/22 VAD (30.4%) by MRT/MRA. When MRT/MRA and DSA results were combined, the specific findings increased to 43.5%. Follow-up examinations revealed recanalization in 52% of initially stenosed or occluded vertebral arteries. With this retrospective approach, we were able to show a high sensitivity of MRT/MRA for the presence of disturbed flow in the dissected vertebral artery. The MRA projections tended to overestimate stenosis and were inferior to DSA in the appreciation of irregularities of the vessel wall. Identification of high-grade stenosis, especially in the presence of distal occlusion, was improved on the MRA source images. The differentiation between luminal thrombus and mural hematoma requires interpretation of MRA source images, together with flow compensated spinecho images. There is a complementary role of MRT/MRA and DSA for an improved overall specificity for vertebral artery dissection. (orig./MG) [Deutsch] Dissektionen der hirnversorgenden Arterien sind eine

Gd-DTPA-enhanced T{sub 1}-weighted excretory MR urography after low-dose diuretic injection; T{sub 1}-gewichtete MR-Ausscheidungsurographie mittels Gd-DTPA und vorheriger niedrigdosierter Gabe eines Diuretikums

Energy Technology Data Exchange (ETDEWEB)

Nolte-Ernsting, C.; Buecker, A.; Adam, G.; Neuerburg, J.; Guenther, R.W. [Universitaetsklinikum der RWTH Aachen (Germany). Klinik fuer Radiologische Diagnostik

1997-09-01

Purpose: Assessment of the morphology of the urinary tract by gadolinium(Gd)-enhanced T{sub 1}-weighted MR-urography (MRU) and precontrast diuretic injection. Methods: MRU was performed in 5 patients using Gd-DTPA-enhanced coronal T{sub 1}-weighted 3D-gradient-echo sequences with different spatial resolution. Prior to contrast injection, 10 mg of furosemide were administered intravenously. Results: Secondary to the precontrast furosemide injection, the increase of the renal excretion rate allows complete visualisation of the entire collecting system within 10 minutes following Gd injection. Maximum intensity projections provide a three-dimensional overview of the ureters separate from the bladder. To achieve detailed anatomic imaging of the calices, both optimal distension and high resolution sequences are prerequisites which cannot be realized by means of survey urograms only. (orig./AJ) [Deutsch] Ziel: Darstellung der Morphologie der ableitenden Harnwege mittels T{sub 1}-gewichteter MR-Urographie (MRU) nach Gabe eines nierengaengigen Gadolinium(Gd)-Chelates und vorheriger Diuretikumapplikation. Methoden: Der Harntrakt von 5 Patienten wurde nach Injektion von Gd-DTPA mit koronaren T{sub 1}-gewichteten 3D-Gradienten-Echo-Sequenzen unterschiedlicher Ortsaufloesung untersucht. Vor der Kontrastmittelgabe wurden jeweils 10 mg Furosemid intravenoes verabreicht. Ergebnisse: Nach initialer Steigerung des Harnflusses durch Furosemidgabe wurden Uebersichtsurogramme mit vollstaendig durchzeichnenden Ureteren bereits 10 min nach Gd-Injektion erzielt. Maximumintensitaetsprojektionen ermoeglichten die Beurteilung des dreidimensionalen Verlaufes der Ureteren ohne Blasenueberlagerung. Eine genauere anatomische Darstellung der Nierenkelche erforderte neben einem guten Fuellungszustand eine moeglichst hohe Sequenzaufloesung, die mit Uebersichtsurogrammen allein nicht zu erreichen war. (orig./AJ)

Neurocognitive sparing of desktop microbeam irradiation.

Science.gov (United States)

Bazyar, Soha; Inscoe, Christina R; Benefield, Thad; Zhang, Lei; Lu, Jianping; Zhou, Otto; Lee, Yueh Z

2017-08-11

Normal tissue toxicity is the dose-limiting side effect of radiotherapy. Spatial fractionation irradiation techniques, like microbeam radiotherapy (MRT), have shown promising results in sparing the normal brain tissue. Most MRT studies have been conducted at synchrotron facilities. With the aim to make this promising treatment more available, we have built the first desktop image-guided MRT device based on carbon nanotube x-ray technology. In the current study, our purpose was to evaluate the effects of MRT on the rodent normal brain tissue using our device and compare it with the effect of the integrated equivalent homogenous dose. Twenty-four, 8-week-old male C57BL/6 J mice were randomly assigned to three groups: MRT, broad-beam (BB) and sham. The hippocampal region was irradiated with two parallel microbeams in the MRT group (beam width = 300 μm, center-to-center = 900 μm, 160 kVp). The BB group received the equivalent integral dose in the same area of their brain. Rotarod, marble burying and open-field activity tests were done pre- and every month post-irradiation up until 8 months to evaluate the cognitive changes and potential irradiation side effects on normal brain tissue. The open-field activity test was substituted by Barnes maze test at 8th month. A multilevel model, random coefficients approach was used to evaluate the longitudinal and temporal differences among treatment groups. We found significant differences between BB group as compared to the microbeam-treated and sham mice in the number of buried marble and duration of the locomotion around the open-field arena than shams. Barnes maze revealed that BB mice had a lower capacity for spatial learning than MRT and shams. Mice in the BB group tend to gain weight at the slower pace than shams. No meaningful differences were found between MRT and sham up until 8-month follow-up using our measurements. Applying MRT with our newly developed prototype compact CNT-based image-guided MRT system

MRI of the hyaline knee joint cartilage. Animal experimental and clinical studies; MRT des hyalinen Kniegelenkknorpels. Tierexperimentelle und klinische Untersuchungen

Energy Technology Data Exchange (ETDEWEB)

Adam, G. [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik; Prescher, A. [Technische Hochschule Aachen (Germany). Inst. fuer Anatomie; Nolte-Ernsting, C. [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik; Buehne, M. [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik; Scherer, K. [Technische Hochschule Aachen (Germany). Inst. fuer Versuchstierkunde; Kuepper, W. [Technische Hochschule Aachen (Germany). Inst. fuer Versuchstierkunde; Guenther, R.W. [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik

1994-02-01

The value of MR imaging for the detection of hyaline cartilage lesions using 2-D spin-echo and 3-D gradient-echo imaging was evaluated in an animal experiment in 10 dogs and in a clinical study in 30 patients. MR imaging findings were compared with histopathological and arthroscopy findings, respectively. Using MRI neither grade I nor grade II hyaline cartilage lesions were detectable. In the animal experiments 77% of grade III lesions and all the grade IV lesions were seen. However, in the clinical study only about the half of grade III and IV lesions were detected. 3-D gradient-echo MR imaging was superior to 2-D spin-echo imaging (p<0.001), while 3-D FLASH and 3-D FISP did not differ significantly in the detection rate (p<0.34). 3-D gradient-echo MR imaging seems to be the best method for the delineation of high grade cartilage lesions. However, early stages of cartilage degeneration are invisible even with this imaging modality. (orig.) [Deutsch] Die Wertigkeit der MRT in der Erfassung von Knorpellaesionen mit 2-D-Spin-Echo- und 3-D-Grafienten-Echo-Sequenzen wurde in einer tierexperimentellen Untersuchung an 10 Hunden sowie in einer klinischen Studie an 30 Patienten ueberprueft. Die kernspintomographischen Ergebnisse wurden mit dem pathologisch-anatomischen Befund bzw. der Arthroskopie verglichen. MR-tomographisch konnten weder Grad-I- noch Grad-II-Knorpellaesionen erfasst werden. Die Erkennbarkeitsrate der Grad-III- und -IV-Laesionen lag fuer die tierexperimentellen Untersuchungen bei 77 bzw. 100%, waehrend klinisch nur etwa 50% dieser Veraenderungen erkannt werden konnten. Dabei waren die 3-D-Gradienten-Echo-Sequenzen den 2-D-Spin-Echo-Sequenzen signifikant ueberlegen (p<0,001), waehrend sich die 3-D-Gradienten-Echo-Sequenzen FISP und FLASH nicht voneinander unterschieden (p<0,34). Derzeit muessen die 3-D-Gradienten-Echo-Sequenzen als die beste Methode zur Erfassung hoehergradiger Knorpellaesionen angesehen werden. Fruehe Stadien der Knorpelschaedigung sind

Three-dimensional simulations of Bingham plastic flows with the multiple-relaxation-time lattice Boltzmann model

OpenAIRE

Song-Gui Chen; Chuan-Hu Zhang; Yun-Tian Feng; Qi-Cheng Sun; Feng Jin

2016-01-01

This paper presents a three-dimensional (3D) parallel multiple-relaxation-time lattice Boltzmann model (MRT-LBM) for Bingham plastics which overcomes numerical instabilities in the simulation of non-Newtonian fluids for the Bhatnagar–Gross–Krook (BGK) model. The MRT-LBM and several related mathematical models are briefly described. Papanastasiou’s modified model is incorporated for better numerical stability. The impact of the relaxation parameters of the model is studied in detail. The MRT-L...

High resolution 3D imaging of synchrotron generated microbeams

Energy Technology Data Exchange (ETDEWEB)

Gagliardi, Frank M., E-mail: frank.gagliardi@wbrc.org.au [Alfred Health Radiation Oncology, The Alfred, Melbourne, Victoria 3004, Australia and School of Medical Sciences, RMIT University, Bundoora, Victoria 3083 (Australia); Cornelius, Iwan [Imaging and Medical Beamline, Australian Synchrotron, Clayton, Victoria 3168, Australia and Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales 2500 (Australia); Blencowe, Anton [Division of Health Sciences, School of Pharmacy and Medical Sciences, The University of South Australia, Adelaide, South Australia 5000, Australia and Division of Information Technology, Engineering and the Environment, Mawson Institute, University of South Australia, Mawson Lakes, South Australia 5095 (Australia); Franich, Rick D. [School of Applied Sciences and Health Innovations Research Institute, RMIT University, Melbourne, Victoria 3000 (Australia); Geso, Moshi [School of Medical Sciences, RMIT University, Bundoora, Victoria 3083 (Australia)

2015-12-15

Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy. Methods: Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25–50 μm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a NIKON A1 laser fluorescence confocal microscope. Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 μm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured. Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery.

High resolution 3D imaging of synchrotron generated microbeams

International Nuclear Information System (INIS)

Gagliardi, Frank M.; Cornelius, Iwan; Blencowe, Anton; Franich, Rick D.; Geso, Moshi

2015-01-01

Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy. Methods: Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25–50 μm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a NIKON A1 laser fluorescence confocal microscope. Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 μm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured. Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery

Clinical value of FDG hybrid-PET in staging and restaging of malignant lymphoma. Compared with conventional diagnostic methods; Klinische Wertigkeit der Befunde von FDG-PET mittels Koinzidenz-Gammakamera beim Staging und Restaging maligner Lymphome. Ein Vergleich zu konventioneller Diagnostik

Energy Technology Data Exchange (ETDEWEB)

Pichler, R.; Maschek, W.; Hatzl-Griesenhofer, M.; Huber, H. [Allgemeines Krankenhaus Linz (Austria). Inst. fuer Nuklearmedizin; Wimmer, G.; Wahl, G.; Fridrik, M. [Allgemeines Krankenhaus Linz (Austria). I. Medizinische Abt.

2000-09-01

Aim of the present retrospective study was to validate the clinical value of F-18-FDG PET imaging in lymphoma patients with a dual head camera modified for coincidence detection. Staging before and after oncological treatment was compared with a conservative diagnostic approach. Methods: 48 patients (28 non-Hodgkin lymphoma, 20 Hodgkin's disease) received FDG-Hybrid-PET scans. Pretherapeutic staging was realized in 28 patients, 9 of them had control studies after they had completed therapy. Totally 29 persons were examined for posttherapeutic restaging. Computed tomography imaging and lymph node sonography was performed in all cases. Results were validated by clinical follow-up, in three cases a recidive was proven by biopsy. Results: CT and ultrasound detected 77 lesions in 28 patients compared with 100 visualized by PET, but this difference in pretherapeutic staging did not reach significance at p>0.05 by Fisher's t-test. Hybrid-PET obtained a sensitivity of 93%, a specifity of 79%, a positive of 82% and a negative predictive value of 92% for detection of residual disease. The values for CT+US were 87%, 64%, 72% and 88% respectively. Conclusion: FDG Hybrid-PET is as or even more accurate than standard morphologic diagnostic methods for prestaging in malignant lymphoma. Additionally, there is a substancial benefit for therapy monitoring of residual disease using coincidence detection PET with a 3/4-inch crystal gamma camera. (orig.) [German] Ziel der vorliegenden retrospektiven Studie war die Validierung der klinischen Wertigkeit von F-18-FDG-PET mittels Doppelkopf-Koinzidenz-Gammakamera bei Lymphompatienten. Die Ergebnisse von prae- und post-therapeutischem Staging wurden mit dem konservativ bildgebender Verfahren verglichen. Methoden: 48 Patienten (28 NHL, 20 Morbus Hodgkin) erhielten FDG-DK-PET-Untersuchungen. Ein praetherapeutisches Staging wurde bei 28 Patienten durchgefuehrt, 9 von diesen hatten weitere Kontrollstudien nach abgeschlossenem

MRI of the heart, the great vessels and the mediastinum

International Nuclear Information System (INIS)

Obletter, N.; Picker, D.; Stirner, H.; Schmitt, R.; Helmberger, T.

1994-01-01

The article surveys the most important indications for MRT of the heart, the great vessels and the mediastinum. MRT is clearly indicated with search or clarification of aneurysms of the heart wall, atrial or ventriucular septal defects with shunting or other congenital vitia in children or in the newborn, aortic aneurysms as well as connatal defects. MRT is superior to other screening methods when clarifying mediastinal neoplasms because of its multiplanar presentation and its strong quality in contrasting soft tissue. With MRT impressive dynamic studies can be obtained through cine modes and gradient echo sequences, which are very successfully used for aortic and mitral valve stenoses, for aneurysms of the heart wall, for aortic aneurysms and atrial and septal shunts. (orig./MG) [de

Synchrotron microbeam radiation therapy for rat brain tumor palliation-influence of the microbeam width at constant valley dose

International Nuclear Information System (INIS)

Serduc, Raphael; Fonta, Caroline; Renaud, Luc; Bouchet, Audrey; Braeuer-Krisch, Elke; Sarun, Sukhena; Bravin, Alberto; Le Duc, Geraldine; Laissue, Jean A; Spiga, Jenny; Boutonnat, Jean; Siegbahn, Erik Albert; Esteve, Francois

2009-01-01

To analyze the effects of the microbeam width (25, 50 and 75 μm) on the survival of 9L gliosarcoma tumor-bearing rats and on toxicity in normal tissues in normal rats after microbeam radiation therapy (MRT), 9L gliosarcomas implanted in rat brains, as well as in normal rat brains, were irradiated in the MRT mode. Three configurations (MRT25, MRT50, MRT75), each using two orthogonally intersecting arrays of either 25, 50 or 75 μm wide microbeams, all spaced 211 μm on center, were tested. For each configuration, peak entrance doses of 860, 480 and 320 Gy, respectively, were calculated to produce an identical valley dose of 18 Gy per individual array at the center of the tumor. Two, 7 and 14 days after radiation treatment, 42 rats were killed to evaluate histopathologically the extent of tumor necrosis, and the presence of proliferating tumors cells and tumor vessels. The median survival times of the normal rats were 4.5, 68 and 48 days for MRT25, 50 and 75, respectively. The combination of the highest entrance doses (860 Gy per array) with 25 μm wide beams (MRT25) resulted in a cumulative valley dose of 36 Gy and was excessively toxic, as it led to early death of all normal rats and of ∼50% of tumor-bearing rats. The short survival times, particularly of rats in the MRT25 group, restricted adequate observance of the therapeutic effect of the method on tumor-bearing rats. However, microbeams of 50 μm width led to the best median survival time after 9L gliosarcoma MRT treatment and appeared as the better compromise between tumor control and normal brain toxicity compared with 75 μm or 25 μm widths when used with a 211 μm on-center distance. Despite very high radiation doses, the tumors were not sterilized; viable proliferating tumor cells remained present at the tumor margin. This study shows that microbeam width and peak entrance doses strongly influence tumor responses and normal brain toxicity, even if valley doses are kept constant in all groups. The use

Synchrotron microbeam radiation therapy for rat brain tumor palliation-influence of the microbeam width at constant valley dose

Energy Technology Data Exchange (ETDEWEB)

Serduc, Raphael; Fonta, Caroline; Renaud, Luc [Universite de Toulouse, UPS, Centre de Recherche Cerveau et Cognition (France); Bouchet, Audrey; Braeuer-Krisch, Elke; Sarun, Sukhena; Bravin, Alberto; Le Duc, Geraldine [European Synchrotron Radiation Facility, F38043 Grenoble (France); Laissue, Jean A [Institute of Pathology, University of Bern (Switzerland); Spiga, Jenny [Department of Physics, University of Cagliari, s.p. Monserrato-Sestu, Monserrato (Canada) 09042 (Italy); Boutonnat, Jean [TIMC lab, UMR CNRS 5525, Univ Joseph Fourier, CHU, Grenoble (France); Siegbahn, Erik Albert [Department of Medical Physics, Karolinska Universitetssjukhuset, 17176 Stockholm (Sweden); Esteve, Francois [INSERM U836, Equipe 6, Institut des Neurosciences de Grenoble, 38043 Grenoble Cedex (France)], E-mail: raph.serduc@gmail.com

2009-11-07

To analyze the effects of the microbeam width (25, 50 and 75 {mu}m) on the survival of 9L gliosarcoma tumor-bearing rats and on toxicity in normal tissues in normal rats after microbeam radiation therapy (MRT), 9L gliosarcomas implanted in rat brains, as well as in normal rat brains, were irradiated in the MRT mode. Three configurations (MRT25, MRT50, MRT75), each using two orthogonally intersecting arrays of either 25, 50 or 75 {mu}m wide microbeams, all spaced 211 {mu}m on center, were tested. For each configuration, peak entrance doses of 860, 480 and 320 Gy, respectively, were calculated to produce an identical valley dose of 18 Gy per individual array at the center of the tumor. Two, 7 and 14 days after radiation treatment, 42 rats were killed to evaluate histopathologically the extent of tumor necrosis, and the presence of proliferating tumors cells and tumor vessels. The median survival times of the normal rats were 4.5, 68 and 48 days for MRT25, 50 and 75, respectively. The combination of the highest entrance doses (860 Gy per array) with 25 {mu}m wide beams (MRT25) resulted in a cumulative valley dose of 36 Gy and was excessively toxic, as it led to early death of all normal rats and of {approx}50% of tumor-bearing rats. The short survival times, particularly of rats in the MRT25 group, restricted adequate observance of the therapeutic effect of the method on tumor-bearing rats. However, microbeams of 50 {mu}m width led to the best median survival time after 9L gliosarcoma MRT treatment and appeared as the better compromise between tumor control and normal brain toxicity compared with 75 {mu}m or 25 {mu}m widths when used with a 211 {mu}m on-center distance. Despite very high radiation doses, the tumors were not sterilized; viable proliferating tumor cells remained present at the tumor margin. This study shows that microbeam width and peak entrance doses strongly influence tumor responses and normal brain toxicity, even if valley doses are kept constant in

The effects of sex, sexual orientation, and digit ratio (2D:4D) on mental rotation performance.

Science.gov (United States)

Peters, Michael; Manning, John T; Reimers, Stian

2007-04-01

In spite of the reduced level of experimental control, this large scale study brought some clarity into the relation between mental rotation task (MRT) performance and a number of variables where contradictory associations had previously been reported in the literature. Clear sex differences in MRT were observed for a sample of 134,317 men and 120,783 women, with men outperforming women. There were also MRT differences as a function of sexual orientation: heterosexual men performed better than homosexual men and homosexual women performed better than heterosexual women. Although bisexual men performed better than homosexual men but less well than heterosexual men, no significant differences were observed between bisexual and homosexual women. MRT performance in both men and women peaked in the 20-30 year range, and declined significantly and markedly thereafter. Both men and women showed a significant negative correlation between left and right digit finger ratio and MRT scores, such that individuals with smaller digit ratios (relatively longer ring finger than index finger) performed better than individuals with larger digit ratios.

Functional magnetic resonance imaging for evaluation of radiation-induced renal damage; Funktionelle MRT der Niere zur Erfassung strahleninduzierter Nierenschaedigungen

Energy Technology Data Exchange (ETDEWEB)

Haneder, S.; Schoenberg, S.O.; Michaely, H.J. [Universitaetsmedizin Mannheim, Medizinische Fakultaet Mannheim der Universitaet Heidelberg, Institut fuer Klinische Radiologie und Nuklearmedizin, Mannheim (Germany); Boda-Heggemann, J. [Universitaetsmedizin Mannheim, Medizinische Fakultaet Mannheim der Universitaet Heidelberg, Klinik fuer Strahlentherapie und Radioonkologie, Mannheim (Germany)

2012-03-15

The diagnosis of radiation-induced (especially chronic) renal alterations/damage is difficult and currently relies primarily on clinical evaluation. The importance of renal diagnostic evaluation will increase continuously due to the increasing number of long-term survivors after radiotherapy. This article evaluates the potentia diagnostic contribution of magnetic resonance (MR) imaging with a focus on functional MRI. The following functional MRI approaches are briefly presented and evaluated: blood oxygenation level-dependent imaging (BOLD), diffusion-weighted imaging (DWI) or diffusion tensor imaging (DTI), MR perfusion measurements and {sup 23}Na imaging. In summary, only DWI and contrast-enhanced MR perfusion currently seem to be suitable approaches for a broader, clinical implementation. However, up to now valid data from larger patient studies are lacking for both techniques in regard to radiation-induced renal alterations. The BOLD and {sup 23}Na imaging procedures have a huge potential but are currently neither sufficiently evaluated with regard to radiation-induced renal alterations nor technically simple and reliable for implementation into the clinical routine. (orig.) [German] Die Diagnostik strahleninduzierter, insbesondere chronischer Schaedigungen der Niere ist nach wie vor schwierig und beruht primaer auf der klinischen Beurteilung. Durch die zunehmende Anzahl von Langzeitueberlebenden nach einer Strahlentherapie wird die Bedeutung dieser Diagnostik jedoch weiter zunehmen. In diesem Beitrag wird der Frage nachgegangen, in wieweit hierzu die MRT-Bildgebung und hier besonders die funktionellen Bildgebungsmodalitaeten ihren Beitrag leisten koennen. Die folgenden Verfahren werden kurz vorgestellt und bewertet: die Blood-oxygenation-level-dependent-Bildgebung (BOLD), die diffusionsgewichtete Bildgebung (''diffusion-weighted imaging'', DWI) bzw. das ''diffusion tensor imaging'' (DTI), die MR-Perfusionsmessungen, und

The rates of carbon cycling in several soils from AMS14C measurements of fractionated soil organic matter

International Nuclear Information System (INIS)

Trumbore, S.E.; Bonani, G.; Wolfli, W.

1990-01-01

14 C mean residence times (MRT) of fractionated organic matter are reported for three pre-bomb soil profiles. Comparisons of organic matter extracted with acid and base showed that the longest MRTs were associated with the non-acid-hydrolysable fraction. The MRT of organic matter in a soil layer represents a combination of the rates of several processes, including decay to CO 2 and transport out of the layer. In some instances (notably in the A horizon of the Podzol soil studied in this paper), the MRT is dominated by the rate of transport, rather than the rate of decay. Thus it is important to use the distribution and balance of carbon in the soil profile to assess the meaning of the MRT with respect to influencing atmospheric CO 2

Fetal lung development on MRI. Normal course and impairment due to premature rupture of membranes; Fetale Lungenentwicklung in der MRT. Normaler Verlauf und Beeintraechtigung durch vorzeitigen Blasensprung

Energy Technology Data Exchange (ETDEWEB)

Kasprian, G. [Medizinische Universitaet Wien (Austria). Klinik fuer Radiodiagnostik; Zentrum fuer Anatomie und Zellbiologie der Medizinischen Universitaet Wien (Austria). Arbeitsgruppe Integrative Morphologie; Brugger, P.C. [Zentrum fuer Anatomie und Zellbiologie der Medizinischen Universitaet Wien (Austria). Arbeitsgruppe Integrative Morphologie; Helmer, H.; Langer, M. [Medizinische Universitaet Wien (Austria). Klinik fuer Frauenheilkunde; Balassy, C.; Prayer, D. [Medizinische Universitaet Wien (Austria). Klinik fuer Radiodiagnostik

2006-02-15

A well-organized interplay between many molecular factors as well as mechanical forces influence fetal lung development. At the end of this complex process a sufficiently sized and structurally mature organ should ensure the postnatal survival of the newborn. Besides prenatal ultrasonography, magnetic resonance imaging (MRI) can now be used to investigate normal and pathological human lung growth in utero. Oligohydramnios, due to premature rupture of membranes (PROM), is an important risk factor for compromised fetal lung growth. In these situations MR volumetry can be used to measure the size of the fetal lung quite accurately. Together with the evaluation of lung signal intensities on T2-weighted sequences, fetuses with pulmonary hypoplasia can be readily detected. (orig.) [German] Die fetale Lungenentwicklung wird einerseits durch eine Vielzahl molekularer Faktoren und andererseits durch mechanisch-physiologische Kraefte beeinflusst. Ein geordnetes Zusammenspiel dieser Mechanismen fuehrt zu einem ausreichend grossen und strukturell reifen Organ, das sofort nach der Geburt das Ueberleben des Neugeborenen sicherstellt. Neben der praenatalen Ultraschalluntersuchung bietet nun auch die Magnetresonanztomographie (MRT) die Moeglichkeit, die normale und pathologische fetale Lungenentwicklung zu untersuchen. Ein wesentlicher Risikofaktor fuer eine Beeintraechtigung der Lungenentwicklung ist die verminderte Fruchtwassermenge nach vorzeitigem Blasensprung. In diesen Faellen kann die MR-Volumetrie dazu eingesetzt werden, die Groesse der fetalen Lungen relativ genau zu bestimmen. Gemeinsam mit der Beurteilung der MR-Signalintensitaeten des Lungengewebes auf T2-gewichteten Sequenzen koennen Feten mit hypoplastischen Lungen mit zunehmender Sicherheit bereits praenatal identifiziert werden. (orig.)

Radiological diagnostics of pediatric lungs; Radiologische Diagnostik der kindlichen Lunge

Energy Technology Data Exchange (ETDEWEB)

Beer, M.; Ammann, B. [Universitaetsklinikum Ulm, Klinik fuer Diagnostische und Interventionelle Radiologie, Ulm (Germany)

2015-07-15

wichtige Saeule zur Festlegung der Behandlung. Die besondere Bedeutung des Strahlenschutzes bei Kindern bedingt eine veraenderte Methodenwahl im Vergleich zu Erwachsenen. So haben Sonographie und MRT als ergaenzende und/oder weiterfuehrende Untersuchungsmethoden einen hoeheren Stellenwert als die Computertomographie im Erwachsenenalter. Haeufigste Fragestellung ist der Verdacht/Ausschluss einer Pneumonie. Dazu ist eine Thoraxaufnahme im a.-p.- oder p.-a.-Strahlengang ausreichend, teils flankiert von der Thoraxsonographie, um bei Beschwerdepersistenz letztere als Verlaufsbildgebung einzusetzen. Die Sonographie wird zudem zur Abklaerung auffaelliger Strukturen im Thoraxraum (Thymus, Sequester) eingesetzt und kann zur definitiven Klaerung fuehren. Der Roentgenthorax ist zudem ideal zur Abklaerung typischer Anpassungsstoerungen nach Geburt wie der transitorischen Tachypnoe (''wet lung disease'') oder dem Surfactantmangel. Durchleuchtungsuntersuchungen werden zur Abklaerung bei Aspirations- und/oder Ingestionsverdacht im Kleinkindalter eingesetzt. Die Computertomographie hat Bedeutung im Staging bzw. in der Nachsorge von Tumorerkrankungen. Technische Neuerungen (z. B. iterative Rekonstruktion) haben zu einer signifikanten Minderung der Strahlenexposition der CT gefuehrt. Die MRT wird derzeit nur vereinzelt zur Abklaerung bei Anlagestoerungen (Sequester) oder Tumorerkrankungen eingesetzt, ihr Potenzial zur Darstellung funktioneller Aspekte (Perfusion und Ventilation) laesst aber einen breiteren Einsatz in Zukunft erwarten. (orig.)

VIBE with parallel acquisition technique - a novel approach to dynamic contrast-enhanced MR imaging of the liver; VIBE mit paralleler Akquisitionstechnik - eine neue Moeglichkeit der dynamischen kontrastverstaerkten MRT der Leber

Energy Technology Data Exchange (ETDEWEB)

Dobritz, M.; Radkow, T.; Bautz, W.; Fellner, F.A. [Inst. fuer Diagnostische Radiologie, Friedrich-Alexander-Univ. Erlangen-Nuernberg (Germany); Nittka, M. [Siemens Medical Solutions, Erlangen (Germany)

2002-06-01

Leberlaesionen zu sammeln. Material und Methoden: 10 konsekutive Patienten mit verschiedenen pathologischen Befunden (HCC, Haemangiome, Metastasen, Zysten, Adenome) wurden an einem 1.5 T MRT-System untersucht. Zur Anwendung kamen folgende Sequenzen: T{sub 2} TSE und T{sub 1} FLASH nativ, nach Gadolinium-Gabe 6 VIBE-Sequenzen mit iPAT (TR/TE/Matrix/Partitionsdicke/Akquisitionszeit: 6.2 ms/3.2 ms/256 x 192/4 mm/13 s) sowie T{sub 1} FLASH mit Fettsaettigung. Zwei Untersucher beurteilten im Konsensus die einzelnen Sequenzen hinsichtlich Anzahl und Dignitiaet der Laesionen. Ergebnisse: Die VIBE-Sequenz zeigte sich ueberlegen in der Detektion arteriell hyperperfundierter Laesionen mit insgesamt 33 erkannten Herden. In der T{sub 2}-gewichteten TSE-Sequenz wurden 21 und in der nativen T{sub 1}-gewichteten GRE-Sequenz 20 Herde gefunden. Die diagnostische Sicherheit stieg in der VIBE-Sequenz gegenueber den anderen Sequenzen deutlich an. Zusammenfassung: Die VIBE-Sequenz mit iPAT ermoeglicht eine MRT der Leber in hoher oertlicher und zeitlicher Aufloesung, wodurch dynamische Kontrastinformationen ueber das gesamte Organ ermoeglicht werden. Dadurch koennte eine Verbesserung der Detektion fokaler Laesionen erreicht werden. (orig.)

Novel technique for high-precision stereotactic irradiation of mouse brains

Energy Technology Data Exchange (ETDEWEB)

Hartmann, J.; Woelfelschneider, J.; Derer, A.; Fietkau, R.; Gaipl, U.S.; Bert, C.; Frey, B. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Department of Radiation Oncology, Universitaetsklinikum Erlangen, Erlangen (Germany); Stache, C.; Buslei, R.; Hoelsken, A. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Institute of Neuropathology, Universitaetsklinikum Erlangen, Erlangen (Germany); Schwarz, M.; Baeuerle, T. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Institute of Radiology, Preclinical Imaging Platform Erlangen (PIPE), Universitaetsklinikum Erlangen, Erlangen (Germany)

2016-11-15

Small animal irradiation systems were developed for preclinical evaluation of tumor therapy closely resembling the clinical situation. Mostly only clinical LINACs are available, so protocols for small animal partial body irradiation using a conventional clinical system are essential. This study defines a protocol for conformal brain tumor irradiations in mice. CT and MRI images were used to demarcate the target volume and organs at risk. Three 6 MV photon beams were planned for a total dose of 10 fractions of 1.8 Gy. The mouse position in a dedicated applicator was verified by an X-ray patient positioning system before each irradiation. Dosimetric verifications (using ionization chambers and films) were performed. Irradiation-induced DNA damage was analyzed to verify the treatment effects on the cellular level. The defined treatment protocol and the applied fractionation scheme were feasible. The in-house developed applicator was suitable for individual positioning at submillimeter accuracy of anesthetized mice during irradiation, altogether performed in less than 10 min. All mice tolerated the treatment well. Measured dose values perfectly matched the nominal values from treatment planning. Cellular response was restricted to the target volume. Clinical LINAC-based irradiations of mice offer the potential to treat orthotopic tumors conformably. Especially with respect to lateral penumbra, dedicated small animal irradiation systems exceed the clinical LINAC solution. (orig.) [German] Kleintierbestrahlungsanlagen wurden entwickelt um praeklinische Studien in der Tumortherapie unter moeglichst klinischen Bedingungen durchzufuehren. Da an den meisten Instituten nur klinische LINACs zur Verfuegung stehen, werden Standardprotokolle zur Kleintierbestrahlung benoetigt, die konventionelle Systeme nutzen. In dieser Studie wird ein solches Protokoll fuer tumorkonforme Hirnbestrahlung von Maeusen definiert. CT- und MRT-Bilder wurden aufgenommen, um Zielvolumen und

Radiation 2006. In association with the Polymer Division, Royal Australian Chemical Institute. Incorporating the 21st AINSE Radiation Chemistry Conference and the 18th Radiation Biology Conference, conference handbook

International Nuclear Information System (INIS)

Lerch, M. L. F.; Nettelbeck, H.; Takacs, G. J.; Oborn, B.; Zealey, W. J.; Rosenfeld, A. B.; Siegbahn, E. A.; Brauer-Krisch, E.; Bravin, A.

2006-01-01

Full text: Recently the Centre for Medical Radiation Physics initiated a research program to study the effect of applying magnetic fields to synchrotron x-ray microbeams to investigate the feasibility of Magneto-Microbeam Radiation Therapy. Microbeam Radiation Therapy (MRT) is an emerging oncology modality for the treatment of inoperable brain tumours in children currently under development at the European Synchrotron Radiation Facility (ESRF), France. Magneto-MRT is the application of a magnetic field during the MRT procedure. MRT utilizes linear arrays of synchrotron X-ray microbeams with a cross sectional area of typically 25μm x 500μm and a centre-to-centre spacing of 400μm. It has the potential to improve the quality of the MRT treatment by altering the dose deposition of charged particles created by the primary MRT photon beam in the tissue volume being targeted. Experimental measurements have been carried out to investigate the effect of both longitudinal and transverse magnetic fields on the physical parameters that characterize a microbeam array made up of three microbeams. Such parameters include microbeam horizontal cross-section profile, Peak-to-Valley dose ratio and the peak depth dose profile. Significant effects have been observed in both magnetic field orientations for relatively small static magnetic fields of ∼1T. The research has also shown that magnetic fields may be a very useful tool that can be used as a controllable parameter for correlating experimental results with corresponding Monte Carlo simulation data

Identification of the pyramidal tract by neuronavigation based on intraoperative magnetic resonance tractography: correlation with subcortical stimulation

Energy Technology Data Exchange (ETDEWEB)

Bozzao, Alessandro; Romano, Andrea; Calabria, Luigi Fausto; Coppola, Valeria; Fantozzi, Luigi Maria [University of Rome Sapienza, Department of Neuroradiology, Rome (Italy); Angelini, Albina; D' Andrea, Giancarlo; Mastronardi, Luciano; Ferrante, Luigi [University of Rome Sapienza, Department of Neurosurgery, Rome (Italy)

2010-10-15

To demonstrate the accuracy of magnetic resonance tractography (MRT) in localizing the cortical spinal tract (CST) close to brain tumours by using intraoperative electric subcortical stimulation. Nine patients with intra-axial brain tumours underwent neurosurgery. Planning was based on analysis of the course of streamlines compatible with the CST. After tumour removal, intraoperative MRT was reacquired. Sites at various distance from the CST were repeatedly stimulated to assess whether registered motor evoked potential (MEP) could be elicited. All patients were assessed clinically both pre- and postoperatively. The motor function was preserved in all patients. In all patients intraoperative MRT demonstrated shift of the bundle position caused by the surgical procedure. The distance between the estimated intraoperative CST and the point of elicited MEP was 1 cm or less in all nine patients. At distances greater than 2 cm, no patient reported positive MEP. Intraoperative MRT is a reliable technique for localization of CST. In all patients MEP were elicited by direct subcortical electrical stimulation at a distance below 1 cm from the CST as represented by MRT. Brain shifting might impact this evaluation since CST position may change during surgery in the range of 8 mm. (orig.)

Identification of the pyramidal tract by neuronavigation based on intraoperative magnetic resonance tractography: correlation with subcortical stimulation

International Nuclear Information System (INIS)

Bozzao, Alessandro; Romano, Andrea; Calabria, Luigi Fausto; Coppola, Valeria; Fantozzi, Luigi Maria; Angelini, Albina; D'Andrea, Giancarlo; Mastronardi, Luciano; Ferrante, Luigi

2010-01-01

To demonstrate the accuracy of magnetic resonance tractography (MRT) in localizing the cortical spinal tract (CST) close to brain tumours by using intraoperative electric subcortical stimulation. Nine patients with intra-axial brain tumours underwent neurosurgery. Planning was based on analysis of the course of streamlines compatible with the CST. After tumour removal, intraoperative MRT was reacquired. Sites at various distance from the CST were repeatedly stimulated to assess whether registered motor evoked potential (MEP) could be elicited. All patients were assessed clinically both pre- and postoperatively. The motor function was preserved in all patients. In all patients intraoperative MRT demonstrated shift of the bundle position caused by the surgical procedure. The distance between the estimated intraoperative CST and the point of elicited MEP was 1 cm or less in all nine patients. At distances greater than 2 cm, no patient reported positive MEP. Intraoperative MRT is a reliable technique for localization of CST. In all patients MEP were elicited by direct subcortical electrical stimulation at a distance below 1 cm from the CST as represented by MRT. Brain shifting might impact this evaluation since CST position may change during surgery in the range of 8 mm. (orig.)

Stereotactic interstitial brachytherapy for the treatment of oligodendroglial brain tumors

Energy Technology Data Exchange (ETDEWEB)

El Majdoub, Faycal; Neudorfer, Clemens; Maarouf, Mohammad [University Hospital of Cologne, Department of Stereotaxy and Functional Neurosurgery, Cologne (Germany); University of Witten/Herdecke, Department of Stereotaxy and Functional Neurosurgery, Center of Neurosurgery, Cologne-Merheim Medical Center (CMMC), Cologne (Germany); Blau, Tobias; Deckert, Martina [University Hospital of Cologne, Department of Neuropathology, Cologne (Germany); Hellmich, Martin [University Hospital of Cologne, Institute of Statistics, Informatics and Epidemiology, Cologne (Germany); Buehrle, Christian [University Hospital of Cologne, Department of Stereotaxy and Functional Neurosurgery, Cologne (Germany); Sturm, Volker [University Hospital of Cologne, Department of Stereotaxy and Functional Neurosurgery, Cologne (Germany); University Hospital of Wurzburg, Department of Neurosurgery, Wuerzburg (Germany)

2015-12-15

(IBT) mittels Jod{sup 125}-Seeds ({sup 125}I) wurde evaluiert. Darueber hinaus wurden prognostische Faktoren analysiert. Zwischen Januar 1991 und Dezember 2010 wurden 63 Patienten (medianes Alter 43,3 Jahre, Spanne 20,8-63,4 Jahre) mit oligodendroglialen Hirntumoren mittels {sup 125}I-IBT entweder primaer, adjuvant nach inkompletter Resektion oder nach Tumorrezidiv behandelt. Moegliche prognostische Faktoren, welche einen Progress oder das Ueberleben beeinflussen, wurden retrospektiv untersucht. Das errechnete 2-, 5- und 10-Jahres-Gesamtueberleben und progressionsfreie Ueberleben nach IBT betrug fuer WHO-II-Tumoren jeweils 96,9%, 96,9%, 89,8% sowie 96,9%, 93,8% und 47,3 %; fuer WHO-III-Tumoren jeweils 90,3%, 77%, 54,9% sowie 80,6%, 58,4% und 45,9 %. Magnetresonanztomographie-(MRT-)Verlaufskontrollen zeigten eine komplette Remission bei 3 Patienten, eine partielle Remission bei 13 Patienten, einen stabilen Befund bei 17 Patienten sowie einen Tumorprogress bei 31 Patienten. Die mediane Progressionszeit betrug fuer WHO-II-Tumoren 87,6 Monate und fuer WHO-III-Tumoren 27,8 Monate. Der neurologische Status besserte sich bei 10 Patienten und blieb bei 20 Patienten unveraendert. Bei 9 Patienten trat eine Verschlechterung auf. Eine therapiebedingte Mortalitaet wurde nicht beobachtet, wobei eine therapiebedingte temporaere Morbiditaet bei 11 Patienten auftrat. WHO II, KPS ≥ 90 %, frontale Lokalisation und eine Tumoroberflaechendosis > 50 Gy waren mit einem erhoehten Gesamtueberleben assoziiert (p ≤ 0,05); Oligodendrogliome und frontale Lokalisation zeigten eine Assoziation zu einem verlaengerten progressionsfreien Ueberleben (p ≤ 0,05). Unsere Studie zeigt, dass die IBT vergleichbare lokale Tumorkontrollraten erzielt wie die Behandlung mittels Mikrochirurgie und Strahlen-/Chemotherapie, minimal-invasiv und sicher ist. Aufgrund der niedrigen Nebenwirkungsrate ist die IBT eine gute Option innerhalb eines multimodalen Therapieschemas unterstuetzend zur Mikrochirurgie oder

Economic evaluation of multidisciplinary rehabilitation treatment versus cognitive behavioural therapy for patients with chronic fatigue syndrome: A randomized controlled trial.

Science.gov (United States)

Vos-Vromans, Desirée; Evers, Silvia; Huijnen, Ivan; Köke, Albère; Hitters, Minou; Rijnders, Nieke; Pont, Menno; Knottnerus, André; Smeets, Rob

2017-01-01

A multi-centre RCT has shown that multidisciplinary rehabilitation treatment (MRT) is more effective in reducing fatigue over the long-term in comparison with cognitive behavioural therapy (CBT) for patients with chronic fatigue syndrome (CFS), but evidence on its cost-effectiveness is lacking. To compare the cost-effectiveness of MRT versus CBT for patients with CFS from a societal perspective. A multi-centre randomized controlled trial comparing MRT with CBT was conducted among 122 patients with CFS diagnosed using the 1994 criteria of the Centers for Disease Control and Prevention and aged between 18 and 60 years. The societal costs (healthcare costs, patient and family costs, and costs for loss of productivity), fatigue severity, quality of life, quality-adjusted life-year (QALY), and cost-effectiveness ratios (ICERs) were measured over a follow-up period of one year. The main outcome of the cost-effectiveness analysis was fatigue measured by the Checklist Individual Strength (CIS). The main outcome of the cost-utility analysis was the QALY based on the EuroQol-5D-3L utilities. Sensitivity analyses were performed, and uncertainty was calculated using the cost-effectiveness acceptability curves and cost-effectiveness planes. The data of 109 patients (57 MRT and 52 CBT) were analyzed. MRT was significantly more effective in reducing fatigue at 52 weeks. The mean difference in QALY between the treatments was not significant (0.09, 95% CI: -0.02 to 0.19). The total societal costs were significantly higher for patients allocated to MRT (a difference of €5,389, 95% CI: 2,488 to 8,091). MRT has a high probability of being the most cost effective, using fatigue as the primary outcome. The ICER is €856 per unit of the CIS fatigue subscale. The results of the cost-utility analysis, using the QALY, indicate that the CBT had a higher likelihood of being more cost-effective. The probability of being more cost-effective is higher for MRT when using fatigue as primary

Factors influencing the residence time of catchment waters : A virtual experiment approach

NARCIS (Netherlands)

Dunn, S.M.; McDonnell, J.J.; Vaché, K.B.

Estimates of mean residence time (MRT) are increasingly used as simple summary descriptors of the hydrological processes involving storage and mixing of water within catchment systems. Current understanding of the physical controls on MRT remains limited, and various hypotheses have been proposed to

The nasopharyngeal angiofibroma

International Nuclear Information System (INIS)

Ternitskaya, Yu.P.

2003-01-01

The CT and MRT features of the nasopharyngeal angiofibroma on basis of 12 patients was studied. Combined CT and MRT examination allowed to define nasopharyngeal angiofibroma's typical signs, to appreciate limits, to contribute to differential diagnosis of inflammatory diseases of the paranasal sinuses

Physics study of microbeam radiation therapy with PSI-version of Monte Carlo code GEANT as a new computational tool

CERN Document Server

Stepanek, J; Laissue, J A; Lyubimova, N; Di Michiel, F; Slatkin, D N

2000-01-01

Microbeam radiation therapy (MRT) is a currently experimental method of radiotherapy which is mediated by an array of parallel microbeams of synchrotron-wiggler-generated X-rays. Suitably selected, nominally supralethal doses of X-rays delivered to parallel microslices of tumor-bearing tissues in rats can be either palliative or curative while causing little or no serious damage to contiguous normal tissues. Although the pathogenesis of MRT-mediated tumor regression is not understood, as in all radiotherapy such understanding will be based ultimately on our understanding of the relationships among the following three factors: (1) microdosimetry, (2) damage to normal tissues, and (3) therapeutic efficacy. Although physical microdosimetry is feasible, published information on MRT microdosimetry to date is computational. This report describes Monte Carlo-based computational MRT microdosimetry using photon and/or electron scattering and photoionization cross-section data in the 1 e V through 100 GeV range distrib...

Persistence of dysphagia and odynophagia after mediastinal radiation and chemotherapy in patients with lung cancer or lymphoma.

Science.gov (United States)

Shields, Helen; Li, Justin; Pelletier, Stephen; Wang, Helen; Freedman, Rachel; Mamon, Harvey; Ng, Andrea; Freedman, Arnold; Come, Steven; Avigan, David; Huberman, Mark; Recht, Abram

2017-02-01

Esophageal symptoms are common during radiation and chemotherapy. It is unclear how often these symptoms persist after therapy. We retrospectively reviewed medical records of 320 adults treated for nonmetastatic breast cancer (84), lung cancer (109), or Hodgkin and non-Hodgkin lymphoma (127) who were disease-free at 10-14 months after therapy. Treatment included chemotherapy with or without nonmediastinal radiation therapy (150 patients), chemotherapy plus sequential mediastinal radiation therapy (MRT) (48 patients), chemotherapy plus concurrent MRT (61 patients), or non-MRT only (61 patients). Proton pump inhibitor use was documented. All treatment groups had similar prevalence of the esophageal symptom of heartburn before therapy. Rates were higher during treatment in those who received MRT with or without chemotherapy, but declined by 10-14 months after treatment. However, low baseline rates of dysphagia (4%) and odynophagia (2%) increased significantly after combined chemotherapy and MRT to 72% for dysphagia and 62% for odynophagia (P dysphagia and 11% having odynophagia at 10-14 months after treatment. The use of proton pump inhibitors by patients who had MRT with chemotherapy was significantly increased during and after treatment (P = 0.002). Dysphagia, odynophagia and the use of proton pump inhibitors were significantly more common both during and after treatment than before treatment in patients who received both chemotherapy and mediastinal radiation. Our data highlight the important challenge for clinicians of managing patients with lung cancer and lymphoma who have persistent esophageal problems, particularly dysphagia and odynophagia, at approximately 1 year after treatment. © 2016 International Society for Diseases of the Esophagus.

How can streamflow and climate-landscape data be used to estimate baseflow mean response time?

Science.gov (United States)

Zhang, Runrun; Chen, Xi; Zhang, Zhicai; Soulsby, Chris; Gao, Man

2018-02-01

Mean response time (MRT) is a metric describing the propagation of catchment hydraulic behavior that reflects both hydro-climatic conditions and catchment characteristics. To provide a comprehensive understanding of catchment response over a longer-time scale for hydraulic processes, the MRT function for baseflow generation was derived using an instantaneous unit hydrograph (IUH) model that describes the subsurface response to effective rainfall inputs. IUH parameters were estimated based on the "match test" between the autocorrelation function (ACFs) derived from the filtered base flow time series and from the IUH parameters, under the GLUE framework. Regionalization of MRT was conducted using estimates and hydroclimate-landscape indices in 22 sub-basins of the Jinghe River Basin (JRB) in the Loess Plateau of northwest China. Results indicate there is strong equifinality in determination of the best parameter sets but the median values of the MRT estimates are relatively stable in the acceptable range of the parameters. MRTs vary markedly over the studied sub-basins, ranging from tens of days to more than a year. Climate, topography and geomorphology were identified as three first-order controls on recharge-baseflow response processes. Human activities involving the cultivation of permanent crops may elongate the baseflow MRT and hence increase the dynamic storage. Cross validation suggests the model can be used to estimate MRTs in ungauged catchments in similar regions of throughout the Loess Plateau. The proposed method provides a systematic approach for MRT estimation and regionalization in terms of hydroclimate and catchment characteristics, which is helpful in the sustainable water resources utilization and ecological protection in the Loess Plateau.

High resolution X-ray fluorescence imaging for a microbeam radiation therapy treatment planning system

Science.gov (United States)

Chtcheprov, Pavel; Inscoe, Christina; Burk, Laurel; Ger, Rachel; Yuan, Hong; Lu, Jianping; Chang, Sha; Zhou, Otto

2014-03-01

Microbeam radiation therapy (MRT) uses an array of high-dose, narrow (~100 μm) beams separated by a fraction of a millimeter to treat various radio-resistant, deep-seated tumors. MRT has been shown to spare normal tissue up to 1000 Gy of entrance dose while still being highly tumoricidal. Current methods of tumor localization for our MRT treatments require MRI and X-ray imaging with subject motion and image registration that contribute to the measurement error. The purpose of this study is to develop a novel form of imaging to quickly and accurately assist in high resolution target positioning for MRT treatments using X-ray fluorescence (XRF). The key to this method is using the microbeam to both treat and image. High Z contrast media is injected into the phantom or blood pool of the subject prior to imaging. Using a collimated spectrum analyzer, the region of interest is scanned through the MRT beam and the fluorescence signal is recorded for each slice. The signal can be processed to show vascular differences in the tissue and isolate tumor regions. Using the radiation therapy source as the imaging source, repositioning and registration errors are eliminated. A phantom study showed that a spatial resolution of a fraction of microbeam width can be achieved by precision translation of the mouse stage. Preliminary results from an animal study showed accurate iodine profusion, confirmed by CT. The proposed image guidance method, using XRF to locate and ablate tumors, can be used as a fast and accurate MRT treatment planning system.

SPECT/CT for staging and treatment monitoring in oncology. Applications in differentiated thyroid cancer and liver tumors; SPECT/CT zum initialen Staging und Therapiemonitoring in der Onkologie. Indikationen beim differenzierten Schilddruesenkarzinom und bei Lebertumoren

Energy Technology Data Exchange (ETDEWEB)

Weber, K.; Berger, F.; Reiser, M.F. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Innenstadt, Institut fuer Klinische Radiologie, Muenchen (Germany); Mustafa, M.; Bartenstein, P.; Haug, A. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Klinik und Poliklinik fuer Nuklearmedizin, Muenchen (Germany)

2012-07-15

and SPECT/CT provides more accurate imaging of the arterial supply of the liver and of potential outflows of micro-spheres into other organs. SPECT/CT allows evaluation and quantification of the uptake of liver tumors. Improved postablative staging in patients with differentiated thyroid cancer by SPECT/CT in comparison to radioiodine whole body scans can be achieved. Improved planning and monitoring of SIRT therapies utilizing SPECT/CT leads to optimized therapeutic doses within liver lesions. Integration of SPECT/CT into the clinical standard for postablative staging in patients with DTC is recommended as well as utilization of SPECT/CT during the planning process, for dose calculation and treatment monitoring of SIRT therapies. (orig.) [German] In den letzten Jahren hat die Hybridbildgebung mit Verbindung von funktioneller und morphologischer Information zur Diagnostik zahlreicher Erkrankungen zunehmend an Bedeutung gewonnen. Bei Patienten mit differenziertem Schilddruesenkarzinom (DTC) wird nach erfolgter Radiojodtherapie (RJT) ein planares Ganzkoerperszintigramm zum Staging durchgefuehrt. Die diagnostische Genauigkeit dieser szintigraphischen Methode ist jedoch aufgrund limitierter raeumlicher Aufloesung begrenzt. Die Radioembolisation von mit {sup 90}Yttrium beladenen Mikrosphaeren (selektive interne Radiotherapie, SIRT) ermoeglicht eine wenig invasive Therapie primaerer und sekundaerer Lebertumoren. Zur Vermeidung von Nebenwirkungen der Mikrosphaeren durch einen Abstrom in Darm, Magen und Lunge muss vor Therapiebeginn eine Darstellung des durch die leberversorgenden Arterien versorgten Gebiets mittels {sup 99m}Tc-MAA ({sup 99m}Technetium-makroaggregiertes Albumin) und einer Szintigraphie erfolgen. Auch hier limitiert die begrenzte morphologische Information der Szintigraphie das Therapiemonitoring. {sup 131}Jod-Ganzkoerperszintigramm zum Nachweis einer erfolgreichen Ablation und Staging ca. 3-4 Tage postablativ bei Patienten mit DTC. Ueberwachung des

Quality of MR thermometry during palliative MR-guided high-intensity focused ultrasound (MR-HIFU) treatment of bone metastases

NARCIS (Netherlands)

Lam, Mie K; Huisman, Merel; Nijenhuis, Robbert J; van den Bosch, Maurice; Viergever, Max A; Moonen, Chrit Tw; Bartels, LW

2015-01-01

BACKGROUND: Magnetic resonance (MR)-guided high-intensity focused ultrasound has emerged as a clinical option for palliative treatment of painful bone metastases, with MR thermometry (MRT) used for treatment monitoring. In this study, the general image quality of the MRT was assessed in terms of

Metrological issues in molecular radiotherapy

International Nuclear Information System (INIS)

D'Arienzo, Marco; Capogni, Marco; Smyth, Vere; Cox, Maurice; Johansson, Lena; Bobin, Christophe

2014-01-01

The therapeutic effect from molecular radiation therapy (MRT), on both tumour and normal tissue, is determined by the radiation absorbed dose. Recent research indicates that as a consequence of biological variation across patients the absorbed dose can vary, for the same administered activity, by as much as two orders of magnitude. The international collaborative EURAMET-EMRP project Metrology for molecular radiotherapy (MetroMRT) is addressing this problem. The overall aim of the project is to develop methods of calibrating and verifying clinical dosimetry in MRT. In the present paper an overview of the metrological issues in molecular radiotherapy is provided. (authors)

A method of dosimetry for synchrotron microbeam radiation therapy using radiochromic films and microdensitometry

International Nuclear Information System (INIS)

Crosbie, J. C.; Svalbe, I. D.; Lewis, R. A.

2007-01-01

Full text: Normal tissue displays an exceptional tolerance to high doses of radiation (hundreds of Gy) when delivered as a microplanar array of synchrotron-generated x-rays. Furthermore, MRT has been shown to cause significant tumour growth delay and in some case complete ablation. The biological effects of MRT on tissue are not fully understood. This is further complicated by difficulties in performing accurate dosimetry. The majority of dosimetry performed for MRT has been Monte Carlo simulations. The aim of this work was to utilise film dosimetry and microdensitometry to measure the peak-to-valley dose ratios (PVDRs) for synchrotron microbeam radiation therapy.

The gender difference on the Mental Rotations test is not due to performance factors.

Science.gov (United States)

Masters, M S

1998-05-01

Men score higher than women on the Mental Rotations test (MRT), and the magnitude of this gender difference is the largest of that on any spatial test. Goldstein, Haldane, and Mitchell (1990) reported finding that the gender difference on the MRT disappears when "performance factors" are controlled--specifically, when subjects are allowed sufficient time to attempt all items on the test or when a scoring procedure that controls for the number of items attempted is used. The present experiment also explored whether eliminating these performance factors results in a disappearance of the gender difference on the test. Male and female college students were allowed a short time period or unlimited time on the MRT. The tests were scored according to three different procedures. The results showed no evidence that the gender difference on the MRT was affected by the scoring method or the time limit. Regardless of the scoring procedure, men scored higher than women, and the magnitude of the gender difference persisted undiminished when subjects completed all items on the test. Thus there was no evidence that performance factors produced the gender difference on the MRT. These results are consistent with the results of other investigators who have attempted to replicate Goldstein et al.'s findings.

Magnetic resonance tomography of renal allografts - Diagnostic possibilities

International Nuclear Information System (INIS)

Dewey, C.; Luening, M.

1988-01-01

It is the aim of the use of magnetic resonance tomography (MRT) to reduce the existing insufficiency in imaging diagnostics of complications after kidney transplantation. The topical status of examination technique is presented and the criteria of normal and pathological MRT findings are described in detail. (author)

Heterogeneity of Monosymptomatic Resting Tremor in a Prospective Study: Clinical Features, Electrophysiological Test, and Dopamine Transporter Positron Emission Tomography.

Science.gov (United States)

Zheng, Hua-Guang; Zhang, Rong; Li, Xin; Li, Fang-Fei; Wang, Ya-Chen; Wang, Xue-Mei; Lu, Ling-Long; Feng, Tao

2015-07-05

The relationship between monosymptomatic resting tremor (mRT) and Parkinson's disease (PD) remains controversial. In this study, we aimed to assess the function of presynaptic dopaminergic neurons in patients with mRT by dopamine transporter positron emission tomography (DAT-PET) and to evaluate the utility of clinical features or electrophysiological studies in differential diagnosis. Thirty-three consecutive patients with mRT were enrolled prospectively. The Unified Parkinson's Disease Rating Scale and electromyography were tested before DAT-PET. Striatal asymmetry index (SAI) was calculated, and a normal DAT-PET was defined as a SAI of hygiene score, walking in motor experiences of daily living (Part II) and motor examination (Part III) were significant different between two groups (P postural tremor tend to be higher in the SWEDDs group (P = 0.08 and P = 0.05, respectively). mRT is heterogeneous in presynaptic nigrostriatal dopaminergic degeneration, which can be determined by DAT-PET brain imaging. Clinical and electrophysiological features may provide clues to distinguish PD from SWEDDs.

MR imaging in gynecology and obstetrics; MR-Tomographie in Gynaekologie und Geburtshilfe

Energy Technology Data Exchange (ETDEWEB)

Bauer, M.; Tontsch, P.; Schulz-Wendtland, R. (eds.)

2000-07-01

The toolbook covers the full range of indications for MRI in obstetrics and gynecology. It is the joint work of radiologists and obstetrician-gynecologists and supplies state-of-the-art information needed by doctors in the private practice or a hospital department. Examples from the Table of Contents: Physical principles of MRI, applications and performance aspects. Systematic presentation of diagnostic findings for comparative analysis and assessment. Biological effects and risks. Benign and malignant neoplasms of the mammary glands and the female genital organs. MRI for prenatal care and diagnostic evaluation. New method: MR spectroscopy. (orig./CB) [German] Das Lehrbuch deckt alle Indikationen der MRT in Gynaekologie und Geburtshilfe ab. Es wurde von Radiologen und Frauenaerzten gemeinsam verfasst und ist daher praxisgerecht. Aus dem Inhalt: Physikalische Grundlagen und Durchfuehrung der MRT und Systematik fuer die Beurteilung der MRT-Befunde. Biologische Wirkungen und Risiken, benigne und maligne Erkrankungen der Brustdruese und der weiblichen Genitalorgane. MRT in der Schwangerschaft. Neue Methode: MR-Spektroskopie. (orig./AJ)

Explaining sex differences in mental rotation: role of spatial activity experience.

Science.gov (United States)

Nazareth, Alina; Herrera, Asiel; Pruden, Shannon M

2013-05-01

Males consistently outperform females on mental rotation tasks, such as the Vandenberg and Kuse (1978) Perceptual and Motor Skills, 47(2), 599-604, mental rotation test (MRT; e.g. Voyer et al. 1995) in Psychological Bulletin, 117, 250-265. The present study investigates whether these sex differences in MRT scores can be explained in part by early spatial activity experience, particularly those spatial activities that have been sex-typed as masculine/male-oriented. Utilizing an online survey, 571 ethnically diverse adult university students completed a brief demographic survey, an 81-item spatial activity survey, and the MRT. Results suggest that the significant relation between sex of the participant and MRT score is partially mediated by the number of masculine spatial activities participants had engaged in as youth. Closing the gap between males and females in spatial ability, a skill linked to science, technology, engineering, and mathematics success, may be accomplished in part by encouraging female youth to engage in more particular kinds of spatial activities.

Original article The effect of three-dimensional imaging of well-known objects on time and accuracy of mental rotation

Directory of Open Access Journals (Sweden)

Piotr Francuz

2014-07-01

Full Text Available Background The purpose of this study was to verify hypotheses concerning the effect of three-dimensional imaging and the canonicity of objects presented in the original position on the reaction time (RT and the accuracy (A of mental rotation task (MRT execution. The classical paradigm of MRT, developed by Shepard and Metzler (1971, was used in the experiment. Participants and procedure One hundred fifty-eight undergraduate students (88 female and 70 male, aged 18-30 years, participated in the experiment. All participants had normal vision or corrected vision, and reported no stereo blindness. The sequential version of the MRT was used in the experiment. Participants answered whether the object observed in the second position was only rotated or both rotated and mirror-reversed, in comparison to its original position. The answer (accuracy and its latency (RT were recorded. Results As predicted by the mental rotation model, both the “U”-shaped A-MRT distribution and the inverted “U”-shaped RT-MRT distribution were found, due to the angular disparity. For the RT-MRT, this effect was more pronounced when the objects were displayed stereoscopically than in a plane, and when the objects were presented in the original position from the canonical orientation rather than an unusual point of view. On the other hand, in the case of the A-MRT, an effect of the orientation of objects presented in the original position on strengthening the relationship between accuracy and angular disparity was found. Conclusions The results indicated that the interactions between the presentation of the objects in the mental rotation task (stereoscopically vs. in a plane and the orientation of the object in its original position (canonically vs. unusual are more complicated than would appear from predictions of classical theories of mental rotation. The results of this study are discussed in relation to the theories of recognition and categorization.

Dose-dependent changes in renal {sup 1}H-/{sup 23}Na MRI after adjuvant radiochemotherapy for gastric cancer

Energy Technology Data Exchange (ETDEWEB)

Haneder, Stefan [University Medical Centre Mannheim, University of Heidelberg, Institute of Clinical Radiology and Nuclear Medicine, Mannheim (Germany); University Hospital of Cologne, Department of Radiology, Cologne (Germany); Budjan, Johannes Michael; Schoenberg, Stefan Oswald [University Medical Centre Mannheim, University of Heidelberg, Institute of Clinical Radiology and Nuclear Medicine, Mannheim (Germany); Konstandin, Simon; Schad, Lothar Rudi [University Medical Centre Mannheim, University of Heidelberg, Computer Assisted Clinical Medicine, Mannheim (Germany); Hofheinz, Ralf Dieter [University Medical Centre Mannheim, University of Heidelberg, III. Department of Internal Medicine, Mannheim (Germany); Gramlich, Veronika; Wenz, Frederik; Lohr, Frank; Boda-Heggemann, Judit [University Medical Centre Mannheim, Medical Faculty Mannheim - University of Heidelberg, Department of Radiation Oncology, Mannheim (Germany)

2015-04-01

.043). No participants showed clinical renal impairment. Functional parameters of renal {sup 23}Na MRI after gastric IG-IMRT are identical to those of healthy volunteers, in contrast to renal subvolumes after ablative doses in the control and 3D-CRT patient. While kidney doses to the cortex below 20-25 Gy in fractional doses of ∝ 1 Gy in IG-IMRT (combined with intensified chemotherapy) do not seem to cause significant MRI morphological or functional alterations, doses of > 35 Gy in 1.5-2 Gy fractions clearly result in impairment. (orig.) [German] Die Radiochemotherapie (RCT) des Magenkarzinoms mit 3-dimensionaler konformaler Strahlentherapie (3D-CRT) belastet den linken Nierenoberpol mit ablativen Strahlendosen. Die bildgefuehrte, intensitaetsmodulierte Strahlentherapie (IG-IMRT) ermoeglicht die Aussparung des Nierenparenchyms bei verbesserter Zielvolumenabdeckung. Die Nierenfunktion wurde mit 3 T-funktioneller MRT (diffusionsgewichtete Bildgebung; DWI) und {sup 23}Na-Bildgebung in einer Kohorte von Patienten mit langem Follow-up ausgewertet. Es wurden 5 gesunde Probanden (HV) und 12 Patienten mit Magenkarzinom (11-mal IG-IMRT; 1-mal 3D-CRT) sowie ein Patient als ''positive-Kontrolle'' (nach Behandlung einerMetastase zwischen Milz und linker Niere mit SBRT [''stereotactic-body-radiotherapy'']) untersucht. Die Bestrahlungsdosen wurden fuer die oberen, mittleren und unteren Nierenetagen getrennt dokumentiert. Spaettoxizitaet wurde basierend auf den allgemeinen Toxizitaetskriterien (CTC, Common Toxicity Criteria), mittels Fragebogen und anhand der Kreatininwerte bestimmt. Morphologische Sequenzen, DWI- und {sup 23}Na-Bilder wurden mit einer {sup 1}H/{sup 23}Na-Spule vor und nach intravenoeser Fluessigkeitszufuhr (''water load'', WL) akquiriert. Die statistische Auswertung erfolgte fuer [{sup 23}Na]-Konzentration und ADC (''apparent diffusion coefficient'')-Werte getrennt nach Subvolumina (obere

Antioxidant and cytotoxic properties of lyophilized beer extracts on HL-60 cell line.

Science.gov (United States)

Tedesco, Idolo; Nappo, Annunziata; Petitto, Fabio; Iacomino, Giuseppe; Nazzaro, Filomena; Palumbo, Rosanna; Russo, Gian Luigi

2005-01-01

An impressive number of studies have suggested that red wine can be considered the protective beverage of choice against chronic and degenerative pathologies. Only few and controversial data are available on a potential, similar role for beer, which represents a more cost-effective, safe, and widely available beverage. Starting from the evidence that many antioxidant compounds present in red wine are also present at similar or even higher concentrations in beers, we first screened 48 commercially available beers and selected one (Mrt-HP) with very high polyphenol concentration and antioxidant activity estimated by ferric reducing antioxidant power. We demonstrated that a lyophilized preparation of Mrt-HP beer was cytotoxic with respect to a beer with low polyphenolic content (Trt-LP) when assayed on HL-60 human leukemia cell line. We measured a 60% decrease in cell viability at a polyphenol concentration of 250 microM quercetin equivalents. We also demonstrated that Mrt-HP cytotoxicity was not an artifact due to cell growth conditions because addition of Mrt-HP extracts to cell medium generated peroxide levels indistinguishable from controls. By means of cytofluorimetric analysis of pre-G1 population and caspase 3 activation, we demonstrated that Mrt-HP extracts activated apoptosis in HL-60 cell line. Finally, we found that the concentration of quercetin, resveratrol, and gallic acid in Mrt-HP was 10, 4.6, and 4.6-fold higher, respectively, than in Trt-LP, suggesting that the presence of these molecules might be responsible for the observed cytotoxicity. These data, together with the low in vivo beer toxicity reported in the literature, suggest a possible chemopreventive role for this beverage that requires further studies in animal models.

Boye och "jag" : En grammatisk analys av en litterär persona

OpenAIRE

Lindström, Elina

2015-01-01

I denna uppsats använder jag den interpersonella metafunktionen inom systemisk-funktionell grammatik för att undersöka sex av Karin Boyes dikter, detta med syfte att se huruvida en sådan här analys kan säga något av intresse om diktjaget. Analysen genomfördes enligt Holmberg och Karlssons modell i Grammatik med betydelse, där subjekt och finit tagits ut varpå språkhandlingar markerats och modalitet kommenterats. Dikterna är hämtade ur Boyes Samlade dikter. Av min analys framgår att jaget beha...

Learning Anatomy Enhances Spatial Ability

Science.gov (United States)

Vorstenbosch, Marc A. T. M.; Klaassen, Tim P. F. M.; Donders, A. R. T.; Kooloos, Jan G. M.; Bolhuis, Sanneke M.; Laan, Roland F. J. M.

2013-01-01

Spatial ability is an important factor in learning anatomy. Students with high scores on a mental rotation test (MRT) systematically score higher on anatomy examinations. This study aims to investigate if learning anatomy also oppositely improves the MRT-score. Five hundred first year students of medicine ("n" = 242, intervention) and…

Coupling of sausage, kink, and magneto-Rayleigh-Taylor instabilities in a cylindrical liner

International Nuclear Information System (INIS)

Weis, M. R.; Zhang, P.; Lau, Y. Y.; Gilgenbach, R. M.; Schmit, P. F.; Peterson, K. J.; Hess, M.

2015-01-01

This paper analyzes the coupling of magneto-Rayleigh-Taylor (MRT), sausage, and kink modes in an imploding cylindrical liner, using ideal MHD. A uniform axial magnetic field of arbitrary value is included in each region: liner, its interior, and its exterior. The dispersion relation is solved exactly, for arbitrary radial acceleration (-g), axial wavenumber (k), azimuthal mode number (m), liner aspect ratio, and equilibrium quantities in each region. For small k, a positive g (inward radial acceleration in the lab frame) tends to stabilize the sausage mode, but destabilize the kink mode. For large k, a positive g destabilizes both the kink and sausage mode. Using the 1D-HYDRA simulation results for an equilibrium model that includes a pre-existing axial magnetic field and a preheated fuel, we identify several stages of MRT-sausage-kink mode evolution. We find that the m = 1 kink-MRT mode has a higher growth rate at the initial stage and stagnation stage of the implosion, and that the m = 0 sausage-MRT mode dominates at the main part of implosion. This analysis also sheds light on a puzzling feature in Harris' classic paper of MRT [E. G. Harris, Phys. Fluids 5, 1057 (1962)]. An attempt is made to interpret the persistence of the observed helical structures [Awe et al., Phys. Rev. Lett. 111, 235005 (2013)] in terms of non-axisymmetric eigenmode

Die sprachnorm und die künstlerische sprache I. Tavčars in seinem werdegang

Directory of Open Access Journals (Sweden)

Martina Orožen

1975-11-01

Full Text Available In dem ganzen Zeitraum vom 16. his zum 18. Jahrhundert hemühten sich die slovenischen Schriftsteller urn die sprachliche Richtigkeit und stilistische Voll­ kommenheit des Textes. Die praktischen Resultate dieser Bemühungen waren aller­ dings nicht einheitlich, weil auch·die theoretischen Ansichten in Bezug auf die Umständlichkeiten, in denen sich die Schriftsprache entwickelte, nicht einheitlich und so geklärt waren, wie es heutzutage ist. Die wechselseiten Beziehungen dieser Bestrehungen sind in gegenwärtigen Ahhandlungen dargestellt am sprachlichen Material eines einzigen, aher vornehmen Schriftstellers Ivan Tavčar. Die angefiihrte Durchsicht des sprachlichen Materials lässt schliessen, class sich der Schriftsteller Tavčar in seinen Werken nach den Normen der Schriftsprache richtete. Wenn er selhst diese Normen nicht immer heohachtete, so taten es die Redakteure und die Korrektoren der literarischen Zeitschriften. Die Normen hetrachtete er als etwas Verhindliches, doch unterordnete er sich nicht ahsolut allen Vorschriften, welche die Archaisierung der Sprache hezielten. Die slavischen Leihwörter verwendete er, wenn sie dem Sinne funktionell entsprachen. So verstand es, auch die nicht mehr lehendigen Glieder des sprachlichen Systems zu helehen und hildend zu entwickeln. Geschickt verwendete er alle Moglichkeiten des Duhlettierens sowohl in lexikalischer als auch in syntaktischer Hinsicht. Bei der Auswahl des sprachlichen Ausdruckes war für ihn die Funktion massgehend, weshalh in seinen Satzen sowohl die archaischen als auch die zeitgemässen sprachlichen Mittel stilistisch wertvoll erscheinen. Tavčars Werke zeigen von den Anfangen in den Siehzigerjahren his zum Ende des 19. Jahrhunderts eine heneidenswerte sprachliche Entwicklung. Trotz der heengenden Normen der Neunzigerjahre fühlte er sich ungehunden und leistete viel für die Entwicklung der Schriftsprache. In der Zeit, wo die Sprache in ihren Regeln eine höhere Stufe der

Sex-Specific Response Strategies in Mental Rotation

Science.gov (United States)

Hirnstein, Marco; Bayer, Ulrike; Hausmann, Markus

2009-01-01

The present study investigated whether the marked sex difference in the original mental rotation test (MRT) is simply a result of sex differences in response strategies. Thirty-four participants (17 males, 17 females) completed the revised Vandenberg and Kuse MRT [Peters, M., Laeng, B., Latham, K., Jackson, M., Zaiyouna, R., & Richardson, C.…

Increased Specificity of Wechsler Adult Intelligence Scale-Third Edition Matrix Reasoning Test Instructions and Time Limits

Science.gov (United States)

Callens, Andy M.; Atchison, Timothy B.; Engler, Rachel R.

2009-01-01

Instructions for the Matrix Reasoning Test (MRT) of the Wechsler Adult Intelligence Scale-Third Edition were modified by explicitly stating that the subtest was untimed or that a per-item time limit would be imposed. The MRT was administered within one of four conditions: with (a) standard administration instructions, (b) explicit instructions…

Præoperativ funktionel magnetisk resonans-billeddannelse hos patienter med hjernetumor

DEFF Research Database (Denmark)

Laustsen, Søren Ravn; Sørensen, Preben; Fründ, Torben

2010-01-01

to fMRI activation was measured using GE-reformat version 4.2 after raw data had been postprocessed using GE BrainwavePA version 1.3.08130. The neurosurgeons valuation of fMRI in the preoperative decision-making process was obtained using a standard questionnaire. RESULTS: There was a trend...

Fetal MRI; Fetales MRT

Energy Technology Data Exchange (ETDEWEB)

Blondin, D. [Inst. fuer Diagn. Radiologie, Uniklinikum Duesseldorf (Germany); Turowski, B. [Inst. fuer Diagn. Radiologie, Neuroradiologie, Uniklinikum Duesseldorf (Germany); Schaper, J. [Inst. fuer Diagn. Radiologie, Kinderradiologie, Uniklinikum Duesseldorf (Germany)

2007-02-15

Ultrasonography is the method of choice for prenatal malformation screening, but it does not always provide sufficient information for correct diagnosis or adequate abnormality evaluation. Fetal MRI is increasingly being used to complete sonographic findings. It was initially used for evaluation of cerebral abnormalities but is increasingly being applied to other fetal areas. In vivo investigation of fetal brain maturation has been enhanced by MRI. An adequate analysis of fetal chest and abdomen can be achieved with fast T2-, T1-weighted and diffusion-weighted imaging (DWI). The advantages include the great field of view and the excellent soft tissue contrast. This allows correct diagnosis of congenital diaphragmatic hernia and evaluation of the consequences on pulmonary growth. Other pulmonary malformations, such as cystic adenomatoid malformation, sequestration and brochogenic cysts, can also be easily identified. Renal position can be quickly determined using DWI sequences and renal agenesia can be easily diagnosed with only one sequence. Prenatal MRI is virtually as effective as postnatal examination, dispenses with transport of a potentially very ill newborn, and provides logistic advantages. Therefore, prenatal MRI is useful for adequate postnatal treatment of newborns with malformations. (orig.)

Sacroiliitis in children with spondyloarthropathy: therapeutic effect of CT-guided intra-articular corticosteroid injection; Sakroiliitis bei Kinder mit Spondylarthropathie: Therapeutischer Effekt der CT-gestuetzten intraartikulaeren Kortikosteroid-Injektionen

Energy Technology Data Exchange (ETDEWEB)

Fischer, T.; Hermann, K.G.A.; Diekmann, F.; Hamm, B. [Humboldt-Universitaet, Berlin (Germany). Universitaetsklinikum Charite, Inst. fuer Radiologie; Biedermann, T. [HELIOS Klinikum Berlin (Germany). II. Klinik fuer Kinderheilkunde und Jugendmedizin, Abt. Kinderrheumatologie; Braun, J. [Rheumazentrum Ruhrgebiet, St. Josefs-Krankenhaus (Germany); Bollow, M. [Augusta-Krankenhaus, Bochum (Germany). Inst. fuer Radiologie

2003-06-01

. The follow-up dynamic MRI (0.1 mmol/kg body weight) during therapy showed a statistically significant lower contrast-enhancement in both groups (group 1: 117{+-}43% versus 38{+-}24%, p<0.05; group 2: 127{+-}59% versus 38{+-}22%, p<0.05). One third of the patients of group 2 showed progression of joint destruction despite absence of subjective complaints. (orig.) [German] Ziel: Prospektive Pruefung des therapeutischen Effektes der CT-gesteuerten intraartikulaeren Kortikosteroid-Injektion entzuendlicher Sakroiliakalgelenke (SIG) bei Kindern mit juveniler Spondylarthropathie (jSpA) im Vergleich zur konventionellen Therapie mit nichtsteroidalen Antirheumatika (NSAR) sowie Bestimmung der Wertigkeit der Magnetresonanztomographie (MRT) bei der Indikationsstellung und der Therapieverlaufskontrolle. Material und Methode: Bei 89 Kindern mit bekannter jSpA wurden mittels dynamischer MRT uni- oder bilaterale Sakroiliitiden diagnostiziert. Bei allen 89 Patienten wurde daraufhin eine Therapie mit NSAR eingeleitet bzw. bereits bestehende Therapien fortgesetzt. Vier Wochen nach der diagnostischen MRT wurden zwei Gruppen definiert: 33 Patienten mit klinischem Response auf NSAR (Gruppe 1) und 56 Nonresponder (Gruppe 2). Die Patienten der Gruppe 2 wurden unter Belassung der NSAR zusaetzlich einer CT-gestuetzten (Low-Dose-Technik) intraartikulaeren Kortikosteroid-Injektion zugefuehrt, wobei insgesamt 83 SIG punktiert und infiltriert wurden (27 bilateral, 29 unilateral). Die Indikationsstellung zur Intervention beruhte auf der zuvor MR-tomographisch gesicherten Entzuendungsaktivitaet. Klinische Therapieverlaufskontrollen erfolgten in 8- bis 12-woechigen Intervallen ueber einen Zeitraum von 20 Monaten. MRT-Verlaufskontrollen wurden bei allen 56 Kindern der Gruppe 2 und bei 15 von 33 Kindern der Gruppe 1 in einem Zeitraum von 8{+-}4 Monaten nach der Erstuntersuchung durchgefuehrt. Ergebnisse: Ingesamt 87,5% der komplikationslos punktierten Kinder der Gruppe 2 (Standardtherapie

Direct observation of electrothermal instability structures on intensely Ohmically heated aluminum with current flowing in a surface skin layer

Science.gov (United States)

Awe, Thomas

2017-10-01

Implosions on the Z Facility assemble high-energy-density plasmas for radiation effects and ICF experiments, but achievable stagnation pressures and temperatures are degraded by the Magneto-Rayleigh-Taylor (MRT) instability. While the beryllium liners (tubes) used in Magnetized Liner Inertial Fusion (MagLIF) experiments are astonishingly smooth (10 to 50 nm RMS roughness), they also contain distributed micron-scale resistive inclusions, and large MRT amplitudes are observed. Early in the implosion, an electrothermal instability (ETI) may provide a perturbation which greatly exceeds the initial surface roughness of the liner. Resistive inhomogeneities drive nonuniform current density and Joule heating, resulting in locally higher temperature, and thus still higher resistivity. Such unstable temperature and pressure growth produce density perturbations which seed MRT. For MagLIF liners, ETI seeding of MRT has been inferred by evaluating late-time MRT, but a direct observation of ETI is not made. ETI is directly observed on the surface of 1.0-mm-diameter solid Al rods pulsed to 1 MA in 100 ns via high resolution gated optical imaging (2 ns temporal and 3 micron spatial resolution). Aluminum 6061 alloy rods, with micron-scale resistive inclusions, consistently first demonstrate overheating from distinct, 10-micron-scale, sub-eV spots, which 5-10 ns later merge into azimuthally stretched elliptical spots and discrete strata (40-100 microns wide by 10 microns tall). Axial plasma filaments form shortly thereafter. Surface plasma can be suppressed for rods coated with dielectric, enabling extended study of the evolution of stratified ETI structures, and experimental inference of ETI growth rates. This fundamentally new and highly 3-dimensional dataset informs ETI physics, including when the ETI seed of MRT may be initiated.

Time to reach tacrolimus maximum blood concentration,mean residence time, and acute renal allograft rejection: an open-label, prospective, pharmacokinetic study in adult recipients.

Science.gov (United States)

Kuypers, Dirk R J; Vanrenterghem, Yves

2004-11-01

The aims of this study were to determine whether disposition-related pharmacokinetic parameters such as T(max) and mean residence time (MRT) could be used as predictors of clinical efficacy of tacrolimus in renal transplant recipients, and to what extent these parameters would be influenced by clinical variables. We previously demonstrated, in a prospective pharmacokinetic study in de novo renal allograft recipients, that patients who experienced early acute rejection did not differ from patients free from rejection in terms of tacrolimus pharmacokinetic exposure parameters (dose interval AUC, preadministration trough blood concentration, C(max), dose). However, recipients with acute rejection reached mean (SD) tacrolimus T(max) significantly faster than those who were free from rejection (0.96 [0.56] hour vs 1.77 [1.06] hours; P clearance nor T(1/2) could explain this unusual finding, we used data from the previous study to calculate MRT from the concentration-time curves. As part of the previous study, 100 patients (59 male, 41 female; mean [SD] age, 51.4 [13.8] years;age range, 20-75 years) were enrolled in the study The calculated MRT was significantly shorter in recipients with acute allograft rejection (11.32 [031] hours vs 11.52 [028] hours; P = 0.02), just like T(max) was an independent risk factor for acute rejection in a multivariate logistic regression model (odds ratio, 0.092 [95% CI, 0.014-0.629]; P = 0.01). Analyzing the impact of demographic, transplantation-related, and biochemical variables on MRT, we found that increasing serum albumin and hematocrit concentrations were associated with a prolonged MRT (P calculated MRT were associated with a higher incidence of early acute graft rejection. These findings suggest that a shorter transit time of tacrolimus in certain tissue compartments, rather than failure to obtain a maximum absolute tacrolimus blood concentration, might lead to inadequate immunosuppression early after transplantation.

Mathematical modelling of digesta passage rate, mean retention time and in vivo apparent digestibility of two different lengths of hay and big-bale grass silage in ponies.

Science.gov (United States)

Moore-Colyer, M J S; Morrow, H J; Longland, A C

2003-07-01

Welsh-cross pony geldings (about 300 kg live weight) were used in a 4x4 Latin square experiment to determine the rate of passage and apparent digestibility of unchopped big-bale grass silage (BBL), chopped big-bale grass silage (BBS), unchopped grass hay (HL) and chopped grass hay (HS) offered at approximately 15 g/kg live weight per d. On day 1 of collection weeks, ponies were fed 85 g ytterbium chloride hexahydrate-marked feed 1.5 h after the morning meal. Total faecal collections commenced 8 h later and continued for 168 h. Apparent digestibilities of feed DM, organic matter (OM), crude protein (CP, Nx6.25), acid-detergent fibre (ADF) and neutral-detergent fibre (NDF) were also determined. Faecal excretion data were subjected to the models of Pond et al. (1988) and digesta mean retention time (MRT) calculated from these models and using the algebraic method of Thielmans et al. (1978). Silage had significantly (Peffect. All the models of Pond et al. (1988) accurately described (R(2)>0.8) the pattern of faecal marker excretion. MRT of BBL (29.0 h)>BBS(27 h)>HS and HL (26 h). Compartmental analysis using the G3 model of Pond et al. (1988) showed BBL and HS diets had longer MRT in the time-dependent compartment, whereas BBS and HL had longer MRT in the time-independent compartment. Results from this experiment indicate that BBL and BBS are readily accepted and digested by ponies. While Yb is a successful external marker for determining total tract MRT and for modelling faecal excretion curves in horses, the results did not allow any definite conclusions to be drawn on digesta MRT within the different compartments of the equid gut.

SU-F-T-673: Effects of Cardiac Induced Brain Pulsations On Proton Minibeams

Energy Technology Data Exchange (ETDEWEB)

Eagle, J; Marsh, S [University of Canterbury, Christchurch, Canterbury (New Zealand); Lee, E; Meyer, J [University of Washington, Seattle, WA (United States)

2016-06-15

Purpose: To quantify the dosimetric impact of internal motion within the brain on spatially modulated proton minibeam radiation therapy (pMRT) for small animal research. Methods: The peak-to-valley dose ratio (PVDR) is an essential dosimetric factor for pMRT. Motion of an animal brain caused by cardiac-induced pulsations (CIP) can impact dose deposition. For synchrotron generated high dose rate X-ray microbeams this effect is evaded due to the quasi-instantaneous delivery. By comparison, pMRT potentially suffers increased spread due to lower dose rates. However, for a given dose rate it is less susceptible to beam spread than microbeams, due to the spatial modulation being an order of magnitude larger. Monte Carlo simulations in TOPAS were used to model the beam spread for a 50.5MeV pMRT beam. Motion effects were simulated for a 50mm thick brass collimator with 0.3mm slit width and 1.0mm center-to-center spacing in a water phantom. The maximum motion in a rat brain due to CIP has been reported to be 0.06mm. Motion was simulated with a peak amplitude in the range 0–0.2mm. Results: The impact of 0.06mm peak motion was minimal and reduced the PVDR by about 1% at a depth of 10mm. For 0.2mm peak motion the PVDR was reduced by 16% at a depth of 10mm. Conclusion: For the pMRT beam the magnitude of cardiac-induced brain motion has minimal impact on the PVDR for the investigated collimator geometry. For more narrow beams the effect is likely to be larger. This indicates that delivery of pMRT to small animal brains should not be affected considerably by beamlines with linac compatible dose rates.

Creutzfeldt-Jakob disease. What is the role of magnetic resonance tomography?; Creutzfeldt-Jakob-Krankheit. Welche Rolle spielt die MR-Tomographie?

Energy Technology Data Exchange (ETDEWEB)

Kujat, C. [Inst. fuer Neuroradiologie der Univ. des Saarlandes, Homburg (Germany); Hagen, T. [Inst. fuer Neuroradiologie der Univ. des Saarlandes, Homburg (Germany); Feiden, W. [Abt. fuer Neuropathologie der Univ. des Saarlandes, Homburg (Germany)

1995-11-01

We report three patients with histologically confirmed CJD and confirm that MRI is a valuable tool for the diagnosis of this disease. (orig./MG) [Deutsch] Anhand der MRT-Ergebnisse von 3 Patienten mit histologisch gesicherter CJD und einer Literaturrecherche wird untersucht, ob die MRT einen Beitrag zur Diagnostik der CJD leisten kann. (orig./MG)

Consistent forcing scheme in the cascaded lattice Boltzmann method.

Science.gov (United States)

Fei, Linlin; Luo, Kai Hong

2017-11-01

In this paper, we give an alternative derivation for the cascaded lattice Boltzmann method (CLBM) within a general multiple-relaxation-time (MRT) framework by introducing a shift matrix. When the shift matrix is a unit matrix, the CLBM degrades into an MRT LBM. Based on this, a consistent forcing scheme is developed for the CLBM. The consistency of the nonslip rule, the second-order convergence rate in space, and the property of isotropy for the consistent forcing scheme is demonstrated through numerical simulations of several canonical problems. Several existing forcing schemes previously used in the CLBM are also examined. The study clarifies the relation between MRT LBM and CLBM under a general framework.

Consistent forcing scheme in the cascaded lattice Boltzmann method

Science.gov (United States)

Fei, Linlin; Luo, Kai Hong

2017-11-01

In this paper, we give an alternative derivation for the cascaded lattice Boltzmann method (CLBM) within a general multiple-relaxation-time (MRT) framework by introducing a shift matrix. When the shift matrix is a unit matrix, the CLBM degrades into an MRT LBM. Based on this, a consistent forcing scheme is developed for the CLBM. The consistency of the nonslip rule, the second-order convergence rate in space, and the property of isotropy for the consistent forcing scheme is demonstrated through numerical simulations of several canonical problems. Several existing forcing schemes previously used in the CLBM are also examined. The study clarifies the relation between MRT LBM and CLBM under a general framework.

MR tomography in Kallmann's syndrome

International Nuclear Information System (INIS)

Dewes, W.; Krahe, T.; Klingmueller, D.; Harder, T.; Bonn Univ.

1987-01-01

MR tomography is the only imaging method that can demonstrate atrophy of the olfactory lobe of the brain in olfacto-genital dysplasia (Kallmann's syndrome). The MRT findings in five patients with Kallmann's syndrome are described. The MRT criterion for the presence of Kallmann's syndrome appears to be an interruption or total absence of the olfactory sulcus. (orig.) [de

Follow-up and prognosis of thyroid carcinoma; Nachsorge und Prognose der Schilddruesenkarzinome

Energy Technology Data Exchange (ETDEWEB)

Sandrock, D.; Munz, D.L. [Humboldt-Universitaet, Berlin (Germany). Medizinische Fakultaet Charite

2000-03-01

The follow-up of patients with differentiated thyroid carcinoma is based on guidelines of the appropriate scientific societies like the German Society of Nuclear Medicine (DGN). After (successfull) radioiodine treatment there are follow-up investigations in intervalls (every [half] year, life-long) including ultrasound, serum level of thyroglobulin, TSH, (f)T3, and (f)T4. If recurrent/metastatic disease is suspected further special methods will follow (radioiodine scan, CT, MRI..). 5- and 10-year overall survival rates of paillary carcinoma are in the range of 90% and 80%, of follicular carcinoma in the range of 80% and 70%, respectively. Individual prognosis can be assessed by different scoring systems including factors like age, sex, size, grading, and extent of the disease. The medullary carcinoma has a mediocre prognosis and similar follow-up intervals focusing on the tumor markers calcitonin and CEA and, if necessary, a variety of imaging methods. The anaplastic carcinoma with its bad prognosis needs individual (palliative) symptomatic follow-up. (orig.) [German] Die Nachsorge des differenzierten Schilddruesenkarzinoms orientiert sich an Empfehlungen und Leitlinien der DGN sowie weiterer Fachgesellschaften. Nach (erfolgreicher) Therapie sind in Intervallen (1/2jaehrlich, jaehrlich, lebenslang) ambulante Nachsorgeuntersuchungen mit Sonographie, Thyreoglobulin- und TSH-, [f]T3-, [f]T4-Bestimmung erforderlich. Je nach Rezidiv-/Metastasenverdacht sind gezielte weitere Untersuchungen durchzufuehren (Radiojoddiagnostik, CT, MRT...). Die 5- und 10-Jahres-Ueberlebensraten des papillaeren Karzinoms liegen um 90% bzw. 80%, die des follikulaeren um 80% bzw. 70%. Die Prognose kann mittels diverser Scores bestimmt werden, die u.a. Alter, Geschlecht, Grading, und Ausdehnung der Erkrankung beruecksichtigen. Das medullaere Karzinom hat bei mittlerer Prognose aehnliche Nachsorgeintervalle, orientiert sich an den Tumormarkern Kalzitonin und CEA und gegebenenfalls komplexer

Diagnostic imaging of compression neuropathy; Bildgebende Diagnostik von Nervenkompressionssyndromen

Energy Technology Data Exchange (ETDEWEB)

Weishaupt, D.; Andreisek, G. [Universitaetsspital, Institut fuer Diagnostische Radiologie, Zuerich (Switzerland)

2007-03-15

Compression-induced neuropathy of peripheral nerves can cause severe pain of the foot and ankle. Early diagnosis is important to institute prompt treatment and to minimize potential injury. Although clinical examination combined with electrophysiological studies remain the cornerstone of the diagnostic work-up, in certain cases, imaging may provide key information with regard to the exact anatomic location of the lesion or aid in narrowing the differential diagnosis. In other patients with peripheral neuropathies of the foot and ankle, imaging may establish the etiology of the condition and provide information crucial for management and/or surgical planning. MR imaging and ultrasound provide direct visualization of the nerve and surrounding abnormalities. Bony abnormalities contributing to nerve compression are best assessed by radiographs and CT. Knowledge of the anatomy, the etiology, typical clinical findings, and imaging features of peripheral neuropathies affecting the peripheral nerves of the foot and ankle will allow for a more confident diagnosis. (orig.) [German] Kompressionsbedingte Schaedigungen peripherer Nerven koennen die Ursache hartnaeckiger Schmerzen im Bereich des Sprunggelenks und Fusses sein. Eine fruehzeitige Diagnose ist entscheidend, um den Patienten der richtigen Therapie zuzufuehren und potenzielle Schaedigungen zu vermeiden oder zu verringern. Obschon die klinische Untersuchung und die elektrophysiologische Abklaerungen die wichtigsten Elemente der Diagnostik peripherer Nervenkompressionssyndrome sind, kann die Bildgebung entscheidend sein, wenn es darum geht, die Hoehe des Nervenschadens festzulegen oder die Differenzialdiagnose einzugrenzen. In gewissen Faellen kann durch Bildgebung sogar die Ursache der Nervenkompression gefunden werden. In anderen Faellen ist die Bildgebung wichtig bei der Therapieplanung, insbesondere dann, wenn die Laesion chirurgisch angegangen wird. Magnetresonanztomographie (MRT) und Sonographie ermoeglichen eine

Diagnostic imaging in child abuse; Bildgebende Diagnostik der Kindesmisshandlung

Energy Technology Data Exchange (ETDEWEB)

Stoever, B. [Charite, Campus Virchow-Klinikum, Universitaetsmedizin Berlin, Abteilung Paediatrische Radiologie, CC6, Diagnostische und interventionelle Radiologie und Nuklearmedizin, Berlin (Germany)

2007-11-15

-Verletzung prognostisch bedeutsam. Initial wird bei diesem Verdacht die CT eingesetzt, um Blutung und Oedem darzustellen, im Verlauf werden mittels MRT Blutungsreste sowie residuelle parenchymatoese Laesionen erfasst. Alle Befunde sind auf ihre Differenzialdiagnosen hin zu pruefen, bevor der Misshandlungsverdacht geaeussert wird. (orig.)

Conformal image-guided microbeam radiation therapy at the ESRF biomedical beamline ID17

International Nuclear Information System (INIS)

Donzelli, Mattia; Bräuer-Krisch, Elke; Nemoz, Christian; Brochard, Thierry; Oelfke, Uwe

2016-01-01

Purpose: Upcoming veterinary trials in microbeam radiation therapy (MRT) demand for more advanced irradiation techniques than in preclinical research with small animals. The treatment of deep-seated tumors in cats and dogs with MRT requires sophisticated irradiation geometries from multiple ports, which impose further efforts to spare the normal tissue surrounding the target. Methods: This work presents the development and benchmarking of a precise patient alignment protocol for MRT at the biomedical beamline ID17 of the European Synchrotron Radiation Facility (ESRF). The positioning of the patient prior to irradiation is verified by taking x-ray projection images from different angles. Results: Using four external fiducial markers of 1.7  mm diameter and computed tomography-based treatment planning, a target alignment error of less than 2  mm can be achieved with an angular deviation of less than 2 ∘ . Minor improvements on the protocol and the use of smaller markers indicate that even a precision better than 1  mm is technically feasible. Detailed investigations concerning the imaging dose lead to the conclusion that doses for skull radiographs lie in the same range as dose reference levels for human head radiographs. A currently used online dose monitor for MRT has been proven to give reliable results for the imaging beam. Conclusions: The ESRF biomedical beamline ID17 is technically ready to apply conformal image-guided MRT from multiple ports to large animals during future veterinary trials.

Conformal image-guided microbeam radiation therapy at the ESRF biomedical beamline ID17

Energy Technology Data Exchange (ETDEWEB)

Donzelli, Mattia, E-mail: donzelli@esrf.fr [European Synchrotron Radiation Facility, 71, Avenue des Martyrs, Grenoble 38000, France and The Institute of Cancer Research, 15 Cotswold Road, Sutton SM2 5NG (United Kingdom); Bräuer-Krisch, Elke; Nemoz, Christian; Brochard, Thierry [European Synchrotron Radiation Facility, 71, Avenue des Martyrs, Grenoble 38000 (France); Oelfke, Uwe [The Institute of Cancer Research, 15 Cotswold Road, Sutton SM2 5NG (United Kingdom)

2016-06-15

Purpose: Upcoming veterinary trials in microbeam radiation therapy (MRT) demand for more advanced irradiation techniques than in preclinical research with small animals. The treatment of deep-seated tumors in cats and dogs with MRT requires sophisticated irradiation geometries from multiple ports, which impose further efforts to spare the normal tissue surrounding the target. Methods: This work presents the development and benchmarking of a precise patient alignment protocol for MRT at the biomedical beamline ID17 of the European Synchrotron Radiation Facility (ESRF). The positioning of the patient prior to irradiation is verified by taking x-ray projection images from different angles. Results: Using four external fiducial markers of 1.7  mm diameter and computed tomography-based treatment planning, a target alignment error of less than 2  mm can be achieved with an angular deviation of less than 2{sup ∘}. Minor improvements on the protocol and the use of smaller markers indicate that even a precision better than 1  mm is technically feasible. Detailed investigations concerning the imaging dose lead to the conclusion that doses for skull radiographs lie in the same range as dose reference levels for human head radiographs. A currently used online dose monitor for MRT has been proven to give reliable results for the imaging beam. Conclusions: The ESRF biomedical beamline ID17 is technically ready to apply conformal image-guided MRT from multiple ports to large animals during future veterinary trials.

MR volumetry of the trigeminal nerve in patients with unilateral facial pain; MR-Volumetrie des N. trigeminus bei Patienten mit einseitigen Gesichtsschmerzen

Energy Technology Data Exchange (ETDEWEB)

Kress, B.; Fiebach, J.; Sartor, K.; Stippich, C. [Abt. Neuroradiologie, Neurologische Klinik, Universitaetsklinikum Heidelberg (Germany); Rasche, D.; Tronnier, V. [Neurochirurgische Klinik, Universitaetsklinikum Heidelberg (Germany)

2004-05-01

Region of interest vermessen und aus diesen Messwerten das Volumen des Nervs errechnet. Das Volumen des Nervs wurde im Seitenvergleich intraindividuell verglichen (t-test fuer verbundene Stichproben, p < 0,05) und die Volumenunterschiede bezogen auf die verschiedenen Krankheitsbilder und Probanden wurden miteinander verglichen (t-test, p < 0,05). Ergebnisse: Das Volumen des betroffenen N. trigeminus war bei Patienten mit N.-trigeminus-Neuralgie geringer als auf der gesunden Gegenseite. Der Unterschied war statistisch signifikant (p < 0,05). Bei den uebrigen Patienten und bei den Probanden ergab sich im intraindividuellen Vergleich kein signifikanter Unterschied. Der Volumenunterschied zwischen gesunder und kranker Seite war bei Patienten mit Trigeminusneuralgie signifikant hoeher (p < 0,05) als bei den uebrigen Patienten und bei den Probanden. Schlussfolgerung: Die intraoperativ beschriebene Atrophie des N. trigeminus als Folge des Gefaess-Nerven Konflikts kann magnetresonanztomographisch dargestellt werden. Nur Patienten mit N.-trigeminus-Neuralgie weisen diese Atrophie auf. Somit kann mittels MRT die Folge des Gefaess-Nerven-Konflikts dargestellt und die pathologische Bedeutung eines solchen Konflikts eingeschaetzt werden. (orig.)

Multiple myoma: current recommendations for imaging; Multiples Myelom: Aktuelle Empfehlungen fuer die Bildgebung

Energy Technology Data Exchange (ETDEWEB)

Hillengass, J. [Medizinische Universitaetsklinik, Abteilung fuer Haematologie, Onkologie und Rheumatologie, Heidelberg (Germany); Deutsches Krebsforschungszentrum, Abteilung Radiologie E010, Heidelberg (Germany); Delorme, S. [Deutsches Krebsforschungszentrum, Abteilung Radiologie E010, Heidelberg (Germany)

2012-04-15

zur Erfassung umschriebener Knochendestruktionen, von Osteoporose oder Frakturen. Die Ganzkoerper-low-dose-CT und Ganzkoerper-MRT ermoeglichen eine Darstellung sowohl des mineralisierten Knochens als auch des Knochenmarks mit einer hoeheren Sensitivitaet, hoeherem Patientenkomfort und im Falle der MRT ohne Strahlenbelastung. Nach den Ergebnissen der Literatur sind Schnittbildverfahren dem Roentgenskelettstatus signifikant ueberlegen, wobei die Ganzkoerper-MRT fuer den Nachweis insbesondere eines diffusen Knochenmarkbefalls signifikant besser ist als die Ganzkoerper-CT. Praktisch jeder osteodestruktive Herd ist in der MRT sichtbar. Allerdings ist fuer die Beurteilung der Osteodestruktion selbst wiederum eine CT erforderlich. Die Sensitivitaeten von PET/CT und MRT sind vergleichbar. Wie bereits in einigen Zentren insbesondere in Deutschland umgesetzt, sollten bei Verfuegbarkeit das Ganzkoerper-MRT und das Ganzkoerper-CT den konventionellen Roentgenskelettstatus ersetzen. Bei Erstdiagnose bzw. Verdacht auf eine monoklonale Gammopathie unklarer Signifikanz (MGUS), ''smoldering multiple myeloma'' und symptomatisches multiples Myelom sollten sowohl eine Ganzkoerper-MRT als auch eine Ganzkoerper-CT durchgefuehrt werden. Bei asymptomatischem Myelom oder MGUS waere die Ganzkoerper-MRT bis zur Detektion des ersten umschriebenen Myelomherdes ausreichend. Beim symptomatischen Myelom mit Knochenlaesionen sollten in der Regel die Ganzkoerper-CT und fuer spezielle Fragestellungen die MRT eingesetzt werden. (orig.)

Tuberous sclerosis: Improvement of diagnosis by CT and MRI

International Nuclear Information System (INIS)

Dewes, W.; Henkes, H.; Richter, J.; Kretschmer, A.; Benz, P.; Brill, G.

1992-01-01

Ten children and a 22-y old women with tuberous sclerosis were studied. All children were epileptic but only 8 had skin lesions (white spots, adenoma sebaceum), 4 had rhabdomyoma of the heart and 4 children had strocytoma of the retina; only in 4 children was the entire triad of tuberous sclerosis seen. The young woman with a hemorrhage of an angiolipoma of the kidney had no other symptoms of tuberous sclerosis. All patients had pathologic CT and MRT findings; 4 different types of lesion were seen in MRT. In order to elucidate humangenetic aspects and to demonstrate the underlying disease all children with epileptic disorders and also all patients without the full triad of symptoms should be examined by MRT. (orig.) [de

Vorrichtung zur Thermokoagulation mittels Laserstrahlung

OpenAIRE

Wehner, Martin; Aden, Mirko

2012-01-01

The apparatus has diode lasers (2,4) which emit laser radiation with different central wavelength. The laser radiations from diode lasers are superimposed with each other. A control device (12) is provided for controlling laser power of diode laser. The thermal coagulation process is performed with respect to simultaneous emission of laser radiation from diode laser in processing mode. The ratio of laser power of diode laser in processing mode is changed according to specific pattern and/or a...

Kavitationsdetektion mittels self-sensing-ultraschallwandler

OpenAIRE

Bornmann, Peter; Hemsel, Tobias; Sextro, Walter; Memoli, Gianluca; Hodnett, Mark; Zeqiri, Bajram; Bornmann Peter; Hemsel Tobias; Sextro Walter; Memoli Gianluca; Hodnett Mark; Zeqiri Bajram

2015-01-01

Many processes in chemistry can be enhanced by ultrasound assistance. In many cases ultrasound induced cavitation is the main reason for these enhancements. Therefore, it is desired to quantify cavitation activity during the process to optimize sonication for various processes and monitor cavitation activity throughout the process. One possibility to monitor cavitation activity is to measure the acoustic emissions of oscillating and collapsing cavitation bubbles by hydrophones in the liquid. ...

The Language Faculty – Mind or Brain?

Directory of Open Access Journals (Sweden)

Torben Thrane

2009-05-01

Full Text Available Artiklens sigte er at underkaste Chomskys nyskabende nominale sammensætning – "the mind/brain" – en nøjere undersøgelse. Hovedargumentet er at den skaber en glidebane, således at det der burde være en funktionel diskussion – hvad er det hjernen gør når den behandler sprog? – i stedet bliver en systemdiskussion – hvad er den interne struktur af den menneskelige sprogevne? Argumentet søges ført igennem under streng iagttagelse af de kognitive videnskabers opfattelse af information og repræsentation, specielt som forstået af den amerikanske filosof Frederick I. Dretske.

Memory and survival after microbeam radiation therapy

International Nuclear Information System (INIS)

Schueltke, Elisabeth; Juurlink, Bernhard H.J.; Ataelmannan, Khalid; Laissue, Jean; Blattmann, Hans; Braeuer-Krisch, Elke; Bravin, Alberto; Minczewska, Joanna; Crosbie, Jeffrey; Taherian, Hadi; Frangou, Evan; Wysokinsky, Tomasz; Chapman, L. Dean; Griebel, Robert; Fourney, Daryl

2008-01-01

Background: Disturbances of memory function are frequently observed in patients with malignant brain tumours and as adverse effects after radiotherapy to the brain. Experiments in small animal models of malignant brain tumour using synchrotron-based microbeam radiation therapy (MRT) have shown a promising prolongation of survival times. Materials and methods: Two animal models of malignant brain tumour were used to study survival and memory development after MRT. Thirteen days after implantation of tumour cells, animals were submitted to MRT either with or without adjuvant therapy (buthionine-SR-sulfoximine = BSO or glutamine). We used two orthogonal 1-cm wide arrays of 50 microplanar quasiparallel microbeams of 25 μm width and a center-to-center distance of about 200 μm, created by a multislit collimator, with a skin entrance dose of 350 Gy for each direction. Object recognition tests were performed at day 13 after tumour cell implantation and in monthly intervals up to 1 year after tumour cell implantation. Results: In both animal models, MRT with and without adjuvant therapy significantly increased survival times. BSO had detrimental effects on memory function early after therapy, while administration of glutamine resulted in improved memory

Diagnosis of occipital condyle fractures; Diagnostik von Frakturen der Okzipitalkondylen

Energy Technology Data Exchange (ETDEWEB)

Hefele-Roedel, B. [Radiologische Klinik Innenstadt, Univ. Muenchen (Germany); Vogl, T.J. [Radiologische Klinik Innenstadt, Univ. Muenchen (Germany); Lochbuehler, H. [Dr. v. Haunersches Kinderspital, Kinderchirurgische Klinik, Univ. Muenchen (Germany); Lissner, J. [Radiologische Klinik Innenstadt, Univ. Muenchen (Germany)

1995-01-01

Following the conventional X-ray diagnosis of the skull and upper cervical spine, CT proved to be the primary diagnostic method after a skull and brain injury: For all 4 cases we succeeded in detecting the occipital condyle fracture and in determing its size and location by reconstructions (coronal, sagittal, 3-D). In the case of complex occompanying injuries like soft tissue hematomas (cerebral, in the spinal cord, and the soft tissue of the neck) or for the detection of brain stem contusion, MRT had significant advantages. MRT can offer a higher image quality in soft tissue, especially in the spinal cord and the brain. (orig.) [Deutsch] Im Anschluss an die konventionelle Roentgendiagnostik des Schaedels und der Halswirbelsaeule, erwies sich die Computertomographie als primaer einzusetzendes diagnostisches Verfahren, nach erlittenem Schaedel-Hirn-Trauma. In allen Faellen gelang der exakte Frakturnachweis an den Okzipitalkondylen, die Bestimmung des Frakturausmasses und die genaue Frakturlokalisation in Rekonstruktionen (koronar, sagittal, 3-D). Bei komplexen Begleitverletzungen, wie Blutungen (zerebral, spinal und in den Halsweichteilen) oder zum Nachweis einer Hirnstammkontusion, erwies sich der Einsatz der MRT als vorteilhaft. Mit der MRT laesst sich ein deutlich hoeherer Weichteilkontrast, insbesondere spinal und zerebral, erzielen. (orig.)

Single molecule diffusion and the solution of the spherically symmetric residence time equation.

Science.gov (United States)

Agmon, Noam

2011-06-16

The residence time of a single dye molecule diffusing within a laser spot is propotional to the total number of photons emitted by it. With this application in mind, we solve the spherically symmetric "residence time equation" (RTE) to obtain the solution for the Laplace transform of the mean residence time (MRT) within a d-dimensional ball, as a function of the initial location of the particle and the observation time. The solutions for initial conditions of potential experimental interest, starting in the center, on the surface or uniformly within the ball, are explicitly presented. Special cases for dimensions 1, 2, and 3 are obtained, which can be Laplace inverted analytically for d = 1 and 3. In addition, the analytic short- and long-time asymptotic behaviors of the MRT are derived and compared with the exact solutions for d = 1, 2, and 3. As a demonstration of the simplification afforded by the RTE, the Appendix obtains the residence time distribution by solving the Feynman-Kac equation, from which the MRT is obtained by differentiation. Single-molecule diffusion experiments could be devised to test the results for the MRT presented in this work. © 2011 American Chemical Society

The use of the milk ring test and rose bengal test in brucellosis control and eradication in Nigeria

Directory of Open Access Journals (Sweden)

S.I.B. Cadmus

2008-05-01

Full Text Available In this study, milk and blood samples collected simultaneously from 532 trade cows to be slaughtered at Bodija abattoir, Ibadan (southwestern, Nigeria were examined for antibodies to Brucella using the milk ring test (MRT and the rose bengal test (RBT. Overall, 18.61%of the milk samples were positive according to the MRT, while 9.77 % of the serum samples were positive according to the RBT. The difference was highly significant (Chi-square value 16.33; P<0.05; only 32 (6.02 % of the samples were positive for both tests. The Red Bororo breed of cattle and the White Fulani had the highest positive rates, namely 20.93 % and 11.69%for the MRT and RBT respectively.No conclusion can be drawn about sensitivity because we do not know the true status of the animals tested. It is, however, obvious that although the MRT and RBT are 1st-line screening tests for brucellosis in cows in some countries, their lack of specificity is of concern. Therefore, the requirement for other confirmatory tests that are more specific should be considered for control and eradication of the disease, especially in Nigeria.

In situ biological dose mapping estimates the radiation burden delivered to 'spared' tissue between synchrotron X-ray microbeam radiotherapy tracks.

Directory of Open Access Journals (Sweden)

Kai Rothkamm

Full Text Available Microbeam radiation therapy (MRT using high doses of synchrotron X-rays can destroy tumours in animal models whilst causing little damage to normal tissues. Determining the spatial distribution of radiation doses delivered during MRT at a microscopic scale is a major challenge. Film and semiconductor dosimetry as well as Monte Carlo methods struggle to provide accurate estimates of dose profiles and peak-to-valley dose ratios at the position of the targeted and traversed tissues whose biological responses determine treatment outcome. The purpose of this study was to utilise γ-H2AX immunostaining as a biodosimetric tool that enables in situ biological dose mapping within an irradiated tissue to provide direct biological evidence for the scale of the radiation burden to 'spared' tissue regions between MRT tracks. Γ-H2AX analysis allowed microbeams to be traced and DNA damage foci to be quantified in valleys between beams following MRT treatment of fibroblast cultures and murine skin where foci yields per unit dose were approximately five-fold lower than in fibroblast cultures. Foci levels in cells located in valleys were compared with calibration curves using known broadbeam synchrotron X-ray doses to generate spatial dose profiles and calculate peak-to-valley dose ratios of 30-40 for cell cultures and approximately 60 for murine skin, consistent with the range obtained with conventional dosimetry methods. This biological dose mapping approach could find several applications both in optimising MRT or other radiotherapeutic treatments and in estimating localised doses following accidental radiation exposure using skin punch biopsies.

Exercise-mediated vasodilation in human obesity and metabolic syndrome: effect of acute ascorbic acid infusion.

Science.gov (United States)

Limberg, Jacqueline K; Kellawan, J Mikhail; Harrell, John W; Johansson, Rebecca E; Eldridge, Marlowe W; Proctor, Lester T; Sebranek, Joshua J; Schrage, William G

2014-09-15

We tested the hypothesis that infusion of ascorbic acid (AA), a potent antioxidant, would alter vasodilator responses to exercise in human obesity and metabolic syndrome (MetSyn). Forearm blood flow (FBF, Doppler ultrasound) was measured in lean, obese, and MetSyn adults (n = 39, 32 ± 2 yr). A brachial artery catheter was inserted for blood pressure monitoring and local infusion of AA. FBF was measured during dynamic handgrip exercise (15% maximal effort) with and without AA infusion. To account for group differences in blood pressure and forearm size, and to assess vasodilation, forearm vascular conductance (FVC = FBF/mean arterial blood pressure/lean forearm mass) was calculated. We examined the time to achieve steady-state FVC (mean response time, MRT) and the rise in FVC from rest to steady-state exercise (Δ, exercise - rest) before and during acute AA infusion. The MRT (P = 0.26) and steady-state vasodilator responses to exercise (ΔFVC, P = 0.31) were not different between groups. Intra-arterial infusion of AA resulted in a significant increase in plasma total antioxidant capacity (174 ± 37%). AA infusion did not alter MRT or steady-state FVC in any group (P = 0.90 and P = 0.85, respectively). Interestingly, higher levels of C-reactive protein predicted longer MRT (r = 0.52, P exercise does not alter the time course or magnitude of exercise-mediated vasodilation in groups of young lean, obese, or MetSyn adults. However, systemic inflammation may limit the MRT to exercise, which can be improved with AA. Copyright © 2014 the American Physiological Society.

The workload implications of haptic displays in multi-display environments such as the cockpit: Dual-task interference of within-sense haptic inputs (tactile/proprioceptive) and between-sense inputs (tactile/proprioceptive/auditory/visual)

OpenAIRE

Castle, H

2007-01-01

Visual workload demand within the cockpit is reaching saturation, whereas the haptic sense (proprioceptive and tactile sensation) is relatively untapped, despite studies suggesting the benefits of haptic displays. MRT suggests that inputs from haptic displays will not interfere with inputs from visual or auditory displays. MRT is based on the premise that multisensory integration occurs only after unisensory processing. However, recent neuroscientific findings suggest that t...

NMR imaging of the vertebral column and the spinal canal. 2. rev. and enl. ed.

International Nuclear Information System (INIS)

Forsting, Michael; Uhlenbrock, Detlev; Wanke, Isabel; Universitaetsklinikum Essen

2009-01-01

The book on the MRT (magnetic resonance tomography) of the vertebral cord and spinal canal covers the following topics: physics fundamentals and application; malformation of the spinal canal; degenerative vertebral column diseases; vertebral column and spinal canal carcinomas; inflammatory diseases of the vertebral column and the spinal canal; applicability of MRT in case of acute spinal cord traumata; vascular diseases of the spinal canal

Sound radiation contrast in MR phase images. Method for the representation of elasticity, sound damping, and sound impedance changes; Schallstrahlungskontrast in MR-Phasenbildern. Methode zur Darstellung von Elastizitaets-, Schalldaempfungs- und Schallimpedanzaenderungen

Energy Technology Data Exchange (ETDEWEB)

Radicke, Marcus

2009-12-18

The method presented in this thesis combines ultrasound techniques with the magnetic-resonance tomography (MRT). An ultrasonic wave generates in absorbing media a static force in sound-propagation direction. The force leads at sound intensities of some W/cm{sup 2} and a sound frequency in the lower MHz range to a tissue shift in the micrometer range. This tissue shift depends on the sound power, the sound frequency, the sound absorption, and the elastic properties of the tissue. A MRT sequence of the Siemens Healthcare AG was modified so that it measures (indirectly) the tissue shift, codes as grey values, and presents as 2D picture. By means of the grey values the sound-beam slope in the tissue can be visualized, and so additionally sound obstacles (changes of the sound impedance) can be detected. By the MRT images token up spatial changes of the tissue parameters sound absorption and elasticity can be detected. In this thesis measurements are presented, which show the feasibility and future chances of this method especially for the mammary-cancer diagnostics. [German] Die in dieser Arbeit praesentierte Methode kombiniert Ultraschalltechniken mit der Magnetresonanztomographie (MRT). Eine Ultraschallwelle ruft in absorbierenden Medien eine statische Kraft in Schallausbreitungsrichtung hervor. Die Kraft fuehrt bei Schallintensitaeten von einigen W/cm{sup 2} und einer Schallfrequenz im niederen MHz-Bereich zu einer Gewebeverschiebung im Mikrometerbereich. Diese Gewebeverschiebung haengt ab von der Schallleistung, der Schallfrequenz, der Schallabsorption und den elastischen Eigenschaften des Gewebes. Es wurde eine MRT-Sequenz der Siemens Healthcare AG modifiziert, so dass sie (indirekt) die Gewebeverschiebung misst, als Grauwerte kodiert und als 2D-Bild darstellt. Anhand der Grauwerte kann der Schallstrahlverlauf in dem Gewebe visualisiert werden, und so koennen zusaetzlich Schallhindernisse (Aenderungen der Schallkennimpedanz) aufgespuert werden. Mit den

Die Bibliothek des Bezirksmuseums Josefstadt

Directory of Open Access Journals (Sweden)

Maria Ettl

2015-01-01

Josefstadt in Wien werden die Herkunft der Bibliotheksbestände und die beengte Raumsituation beschrieben. Abschließend wird auf die Erfassung der Medien mittels der Bibliothekssoftware „Biblioweb“ eingegangen.

Survival of rats bearing advanced intracerebral F 98 tumors after glutathione depletion and microbeam radiation therapy: conclusions from a pilot project.

Science.gov (United States)

Schültke, E; Bräuer-Krisch, E; Blattmann, H; Requardt, H; Laissue, J A; Hildebrandt, G

2018-05-10

Resistance to radiotherapy is frequently encountered in patients with glioblastoma multiforme. It is caused at least partially by the high glutathione content in the tumour tissue. Therefore, the administration of the glutathione synthesis inhibitor Buthionine-SR-Sulfoximine (BSO) should increase survival time. BSO was tested in combination with an experimental synchrotron-based treatment, microbeam radiation therapy (MRT), characterized by spatially and periodically alternating microscopic dose distribution. One hundred thousand F98 glioma cells were injected into the right cerebral hemisphere of adult male Fischer rats to generate an orthotopic small animal model of a highly malignant brain tumour in a very advanced stage. Therapy was scheduled for day 13 after tumour cell implantation. At this time, 12.5% of the animals had already died from their disease. The surviving 24 tumour-bearing animals were randomly distributed in three experimental groups: subjected to MRT alone (Group A), to MRT plus BSO (Group B) and tumour-bearing untreated controls (Group C). Thus, half of the irradiated animals received an injection of 100 μM BSO into the tumour two hours before radiotherapy. Additional tumour-free animals, mirroring the treatment of the tumour-bearing animals, were included in the experiment. MRT was administered in bi-directional mode with arrays of quasi-parallel beams crossing at the tumour location. The width of the microbeams was ≈28 μm with a center-to-center distance of ≈400 μm, a peak dose of 350 Gy, and a valley dose of 9 Gy in the normal tissue and 18 Gy at the tumour location; thus, the peak to valley dose ratio (PVDR) was 31. After tumour-cell implantation, otherwise untreated rats had a mean survival time of 15 days. Twenty days after implantation, 62.5% of the animals receiving MRT alone (group A) and 75% of the rats given MRT + BSO (group B) were still alive. Thirty days after implantation, survival was 12.5% in Group A and 62

Quantitative perfusion imaging in magnetic resonance imaging; Quantitative Perfusionsbildgebung in der Magnetresonanztomographie

Energy Technology Data Exchange (ETDEWEB)

Zoellner, F.G.; Gaa, T.; Zimmer, F. [Universitaet Heidelberg, Computerunterstuetzte Klinische Medizin, Medizinische Fakultaet Mannheim, Mannheim (Germany); Ong, M.M.; Riffel, P.; Hausmann, D.; Schoenberg, S.O.; Weis, M. [Universitaet Heidelberg, Institut fuer Klinische Radiologie und Nuklearmedizin, Universitaetsmedizin Mannheim, Medizinische Fakultaet Mannheim, Mannheim (Germany)

2016-02-15

Magnetic resonance imaging (MRI) is recognized for its superior tissue contrast while being non-invasive and free of ionizing radiation. Due to the development of new scanner hardware and fast imaging techniques during the last decades, access to tissue and organ functions became possible. One of these functional imaging techniques is perfusion imaging with which tissue perfusion and capillary permeability can be determined from dynamic imaging data. Perfusion imaging by MRI can be performed by two approaches, arterial spin labeling (ASL) and dynamic contrast-enhanced (DCE) MRI. While the first method uses magnetically labelled water protons in arterial blood as an endogenous tracer, the latter involves the injection of a contrast agent, usually gadolinium (Gd), as a tracer for calculating hemodynamic parameters. Studies have demonstrated the potential of perfusion MRI for diagnostics and also for therapy monitoring. The utilization and application of perfusion MRI are still restricted to specialized centers, such as university hospitals. A broad application of the technique has not yet been implemented. The MRI perfusion technique is a valuable tool that might come broadly available after implementation of standards on European and international levels. Such efforts are being promoted by the respective professional bodies. (orig.) [German] Die Magnetresonanztomographie (MRT) zeichnet sich durch einen ueberlegenen Gewebekontrast aus, waehrend sie nichtinvasiv und frei von ionisierender Strahlung ist. Sie bietet Zugang zu Gewebe- und Organfunktion. Eine dieser funktionellen bildgebenden Verfahren ist die Perfusionsbildgebung. Mit dieser Technik koennen u. a. Gewebeperfusion und Kapillarpermeabilitaet aus dynamischen Bilddaten bestimmt werden. Perfusionsbildgebung mithilfe der MRT kann durch 2 Ansaetze, naemlich ''arterial spin labeling'' (ASL) und dynamische kontrastverstaerkte (DCE-)MRT durchgefuehrt werden. Waehrend die erste Methode magnetisch

Monte Carlo-based treatment planning system calculation engine for microbeam radiation therapy.

Science.gov (United States)

Martinez-Rovira, I; Sempau, J; Prezado, Y

2012-05-01

Microbeam radiation therapy (MRT) is a synchrotron radiotherapy technique that explores the limits of the dose-volume effect. Preclinical studies have shown that MRT irradiations (arrays of 25-75-μm-wide microbeams spaced by 200-400 μm) are able to eradicate highly aggressive animal tumor models while healthy tissue is preserved. These promising results have provided the basis for the forthcoming clinical trials at the ID17 Biomedical Beamline of the European Synchrotron Radiation Facility (ESRF). The first step includes irradiation of pets (cats and dogs) as a milestone before treatment of human patients. Within this context, accurate dose calculations are required. The distinct features of both beam generation and irradiation geometry in MRT with respect to conventional techniques require the development of a specific MRT treatment planning system (TPS). In particular, a Monte Carlo (MC)-based calculation engine for the MRT TPS has been developed in this work. Experimental verification in heterogeneous phantoms and optimization of the computation time have also been performed. The penelope/penEasy MC code was used to compute dose distributions from a realistic beam source model. Experimental verification was carried out by means of radiochromic films placed within heterogeneous slab-phantoms. Once validation was completed, dose computations in a virtual model of a patient, reconstructed from computed tomography (CT) images, were performed. To this end, decoupling of the CT image voxel grid (a few cubic millimeter volume) to the dose bin grid, which has micrometer dimensions in the transversal direction of the microbeams, was performed. Optimization of the simulation parameters, the use of variance-reduction (VR) techniques, and other methods, such as the parallelization of the simulations, were applied in order to speed up the dose computation. Good agreement between MC simulations and experimental results was achieved, even at the interfaces between two

Monte Carlo-based treatment planning system calculation engine for microbeam radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Martinez-Rovira, I.; Sempau, J.; Prezado, Y. [Institut de Tecniques Energetiques, Universitat Politecnica de Catalunya, Diagonal 647, Barcelona E-08028 (Spain) and ID17 Biomedical Beamline, European Synchrotron Radiation Facility (ESRF), 6 rue Jules Horowitz B.P. 220, F-38043 Grenoble Cedex (France); Institut de Tecniques Energetiques, Universitat Politecnica de Catalunya, Diagonal 647, Barcelona E-08028 (Spain); Laboratoire Imagerie et modelisation en neurobiologie et cancerologie, UMR8165, Centre National de la Recherche Scientifique (CNRS), Universites Paris 7 et Paris 11, Bat 440., 15 rue Georges Clemenceau, F-91406 Orsay Cedex (France)

2012-05-15

Purpose: Microbeam radiation therapy (MRT) is a synchrotron radiotherapy technique that explores the limits of the dose-volume effect. Preclinical studies have shown that MRT irradiations (arrays of 25-75-{mu}m-wide microbeams spaced by 200-400 {mu}m) are able to eradicate highly aggressive animal tumor models while healthy tissue is preserved. These promising results have provided the basis for the forthcoming clinical trials at the ID17 Biomedical Beamline of the European Synchrotron Radiation Facility (ESRF). The first step includes irradiation of pets (cats and dogs) as a milestone before treatment of human patients. Within this context, accurate dose calculations are required. The distinct features of both beam generation and irradiation geometry in MRT with respect to conventional techniques require the development of a specific MRT treatment planning system (TPS). In particular, a Monte Carlo (MC)-based calculation engine for the MRT TPS has been developed in this work. Experimental verification in heterogeneous phantoms and optimization of the computation time have also been performed. Methods: The penelope/penEasy MC code was used to compute dose distributions from a realistic beam source model. Experimental verification was carried out by means of radiochromic films placed within heterogeneous slab-phantoms. Once validation was completed, dose computations in a virtual model of a patient, reconstructed from computed tomography (CT) images, were performed. To this end, decoupling of the CT image voxel grid (a few cubic millimeter volume) to the dose bin grid, which has micrometer dimensions in the transversal direction of the microbeams, was performed. Optimization of the simulation parameters, the use of variance-reduction (VR) techniques, and other methods, such as the parallelization of the simulations, were applied in order to speed up the dose computation. Results: Good agreement between MC simulations and experimental results was achieved, even at

A fully variable, piezo-actuated research injection system as a tool in diesel engine combustion process development; Ein vollvariables, piezoaktuiertes Foschungs-Einspritzsystem als Werkzeug in der dieselmotorischen Brennverfahrensentwicklung

Energy Technology Data Exchange (ETDEWEB)

Meyer, S.; Stegemann, J.; Seebode, J.; Merker, G.P. [Hannover Univ. (Germany). Inst. fuer Technische Verbrennung

2004-07-01

The injection process is a central optimisation approach for low-cost, low-emission diesel engines. An injection system is presented which comprises a pressure modulator and a research injector with piezo-actuated direct actuation of the nozzle. The high flexibility of the system enables systematic investigations of different combustion processes. (orig.) [German] Die Einspritzverlaufsformung als Mittel zur Minimierung von Rohemissionen bleibt auch im heutigen, von Diskussionen und Partikelfilter und Entstickungstechnologien gepraegten Umfeld ein zentraler Optimierungsansatz fuer kostenguenstige und emissionsarme Dieselmotoren. Das hier vorgestellte Einspritzsystem, bestehend aus einer Druckmodulationseinheit und einem Forschungsinjektor mit piezogesteuerter Direktansteuerung der Duesennadel, dient zur Potenzialanalyse einer freien Einspritzverlaufsformung als Mittel zur innermotorischen Brennverfahrensoptimierung. Dank der hohen Flexibilitaet des Systems sind systematische Untersuchungen in Bezug auf unterschiedliche Brennverfahren moeglich. (orig.)

Anmeldelse: Funktionel sproglig analyse - en metode til læsning i fagene

DEFF Research Database (Denmark)

Mulvad, Ruth

2011-01-01

Bogen handler om arbejdet med sprog og læsning i skolens fag. I USA er der nemlig - som så mange andre steder verden over - alt for mange elever, som ikke kan læse de komplicerede tekster, som de møder i skolen. Der er også alt for mange lærere, der ikke ved, hvad de skal gribe og gøre i....

Value of new MR techniques in MR-PET; Stellenwert neuer MR-Techniken in der MR-PET

Energy Technology Data Exchange (ETDEWEB)

Attenberger, U.I.; Schoenberg, S.O. [Universitaetsmedizin Mannheim, Medizinische Fakultaet Mannheim der Universitaet Heidelberg, Institut fuer klinische Radiologie und Nuklearmedizin, Mannheim (Germany); Quick, H.H. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Institut fuer Medizinische Physik, Erlangen (Germany); Guimaraes, A. [Massachusetts General Hospital, Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown (United States); Catalano, O. [University of Naples Federico II, Naples (Italy); Morelli, J.N. [The Johns Hopkins Hospital, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore (United States)

2013-12-15

wiederholte Untersuchungen durchlaufen muessen, und paediatrische Patienten relevant ist. Dabei koennen jedoch die Erfahrungen, die im Verlauf der letzten Jahre mit der Hybridtechnologie PET-CT gewonnen wurden, nicht direkt auf die MR-PET uebertragen werden. Ein wesentliches Beispiel hierfuer ist die Schwaechungskorrektur, fuer die in der PET-CT die mittels CT bestimmten Hounsfield-Einheiten verwendet werden. Da die in der PET emittierten 511-keV-Photonen durch das Koerpergewebe des Patienten geschwaecht werden, werden die CT-Datensaetze in sog. lineare Schwaechungskoeffizienten (''linear attenuation coefficients'', LAC) konvertiert. Da die Bilddatenakquisition in der MRT nicht auf einer Schwaechung von Roentgenstrahlung, sondern einer Messung der Protonendichte und von gewebespezifischen Relaxationszeiten basiert, muessen in der MR-PET alternative Verfahren zur Schwaechungskorrektur eingesetzt werden. Darueber hinaus bietet die MRT auch alternative Sequenz- und Akquisitionstechnologien, die es erlauben, bisherige Limitationen z. B. bzgl. der Bewegungskorrektur zu adressieren. Dieser Artikel berichtet ueber initiale klinische Erfahrungen mit einem voll integrierten MR-PET-System, wobei MR-Techniken zur Korrektur von Bewegungsartefakten, die Schwaechungskorrektur und die Reduktion von Metallartefakten im Zentrum stehen. (orig.)

Anwendung der extrakorporalen Stoßwellentherapie bei kalzifizierender Periathropathia humeroscapularis, Fersensporn und Epicondylitis humeri - Erfahrungsbericht aus dem Wilhelminenspital

Directory of Open Access Journals (Sweden)

Feyertag J

2004-01-01

Full Text Available Die Stoßwellentherapie wird bei verschiedenen Indikationen, die unter konservativen Therapien schwer zu schwer zu behandeln sind, eingesetzt. Dazu zählen die kalzifizierenden Schultererkrankungen (Tendinitis calcarea, Epicondylitis humeri (EHR und die plantare Fasciitis mit/ohne plantarem Fersensporn (FSP. Berichtet werden die Ergebnisse von 147 Patienten (102 Frauen/45 Männer, mittleres Alter betrug 57,8 Jahre, die mittels einer einmaligen extrakorporalen Stoßwellentherapie (ESWT (Tend. calc. 82 %, FSP 11 % oder EHR 7 % mittels eines HMT-ReflecTron therapiert wurden. Verabreicht wurden im Mittel 1.800 Stoßwellen. Untersucht wurde die subjektive Verbesserung der Schmerzen anhand einer visuellen Analogskala vor und 6 Wochen nach der Therapie bei allen Patienten. Bei Patienten mit Tendinitis calcarea wurde auch eine Verbesserung der Funktion sowie Veränderungen der Kalzifizierungen untersucht. Bei allen Patienten konnte eine statistisch signifikante Verbesserung der Schmerzen sowie des Bewegungsumfanges beobachtet werden (p 0,0001. Röntgenaufnahmen ergaben eine partielle Verkleinerung der Kalkdepots bei ca. 80 % der Patienten. Aufgrund der geringen Zahl der Patienten fand sich für die EHR keine signifikante Verbesserung der Schmerzsymptomatik. Eine einmalige ESWT kann zu einer deutlichen Verbesserung der Schmerzsymptomatik und zu einer Verbesserung des Bewegungsumfanges führen. Bei 80 % der Patienten mit einer Tendinitis calcarea findet sich weiter eine partielle Verkleinerung der Kalkdepots 6 Wochen nach Therapie.

A comparison of three different physiotherapy modalities used in the physiotherapy of burns.

Science.gov (United States)

Sar, Zübeyir; Polat, Mine Gülden; Özgül, Bahar; Aydoğdu, Onur; Camcoğlu, Burcu; Acar, Ahmet Hakan; Yurdalan, Saadet Ufuk

2013-01-01

The present study compared the effectiveness of matrix rhythm therapy, ultrasound treatment (UT), laser treatment (LT) used in the physiotherapy of burns. The study was conducted at the Wound and Burn Healing Center, Dr. Lütfi Kırdar Kartal Education and Research Hospital (Turkey) from June 2009 to January 2012. The case series comprised 39 individuals with second- and third-degree upper-limb burns, whose burn traumas ended approximately 1 to 3 months previously. Participants were separated into three groups: matrix rhythm treatment (MRT), UT and LT; each group was also applied a treatment protocol including whirlpool and exercise. Pain, range of motion (ROM), muscular strength, skin elasticity, and sensory functions were evaluated before and after the treatment. Pressure sense and passive ROM were higher in the MRT group than in the LT group (P < .05). Pain was lower in the LT group than in the UT group, and passive ROM was higher in the UT group than the in LT group (P < .05). Active ROM was found to increase in all treatment groups, whereas passive ROM increased only in the MRT and UT groups; pressure sense increased only in the MRT group, and pain decreased only in the LT group (P < .05). MRT was found to be more effective in the restoration of sensory functions than LT, whereas LT was more effective in reducing pain than UT. No significant difference was observed in terms of skin elasticity according to the results of three treatment modalities. It is suggested that further research with more cases should be conducted to examine the long-term effect of treatment modalities.

Pre- and post-operative evaluation of ventricular function, muscle mass and valve morphology by MR tomography in Ebstein's anomaly

International Nuclear Information System (INIS)

Gutberlet, M.; Oellinger, H.; Amthauer, H.; Hoffmann, T.; Felix, R.; Ewert, P.; Nagdyman, N.; Lange, P.; Hetzer, R.

2000-01-01

Purpose: To evaluate the value of MRT with spin echo (SE) and CINE gradient echo (GE) sequences for the pre- and postoperative assessment of patients with Ebstein's anomaly. Methods: Twelve patients within the ages of four to 49 years (mean 22±12 years) were examined pre- (n=5) or postoperatively (n=7) after tricuspid valve reconstruction with a 1.5 T scanner. For the anatomical assessment, an ECG-gated transverse SE-sequence, for the assessment of valve morphology and function as well as for volumetry a CINE GE-sequence with retrospective gating was used. With the use of the multislice-multiphase technique, after summing up the manually outlined epi- and endocardial areas, endsystolic (ESV) and enddiastolic volumes (EDV), ejection fraction (EF), stroke volume (SV), and muscle mass (MM) were calculated for both ventricles. Results: The differentiation of the displaced parts of the tricuspid valve (TV) was insufficient with static SE, but was possible in all patients with CINE-MRT. Like in Doppler echocardiography, a qualitative assessment of tricuspid insufficiency was possible in CINE-MRT, the mean incompetence grade preoperative was 1.8 (±0.8), postoperative 0.7 (±0.5). The mean RV-EF in the preoperative group was 41.8% (±6.4), in the postoperative group 47.9% (±10.6), the mean LV-EF preoperative 47.4% (±8.5%), postoperative 63,0% (±9.4). Conclusion: CINE-MRT should rather be used than SE for the assessment of valve morphology. EF, muscle mass and tricuspid incompetence can also be calculated pre- and postoperative with CINE-MRT. (orig.) [de

Beam Characterisation of the Australian Synchrotron Imaging and medical beamline for microbeam radiotherapy research

International Nuclear Information System (INIS)

Gagliardi, F.M.; Midgley, S.; Lewis, R.A.; Ackerly, T.L.

2010-01-01

Full text: Microbeam radiotherapy (MRT) has been developed at synchrotrons around the world over the last two decades. Previous studies have shown normal tissue to be extremely tolerant to MRT at doses normally considered toxic in conventional radiotherapy whilst having a palliative and even curative effect on animal tumours. Our MRT research team has attempted to characterise the beam spectrum of the imaging and medical beamline (TMBL) at the Australian Synchrotron. We also carried out film dosimetry to quantify the peak-to-valley dose ratio for three fixed geometry MRT collimators. The source of X-rays on the IMBL is a 1.4 T wiggler at a distance of 20 m from the sample stage. In vacuo and in-air metal absorbers were used to remove soft X-rays hardening the beam to between 30 and 160 keY. Filters used were 1.5 mm C, 2.5 mm AI, 0.5 mm Be and 0.75 mm Cu. Free air ion chamber measurements and half value layer measurements in conjunction with predictions from a theoretical model based upon a spectrum calculator derived a mean energy of the microbeam of 57 keV with a half value layer of approximately 0.29 mm Cu. The measured air kerma rate was 120 Gy/s. Measurements of the MRT beams created with tungsten/kapton multi-slit collimators on radiographic films were compared with Monte Carlo simulations of the microbeam arrays. The peak-to-valley-dose ratios were found to be 3-4 times lower than predicted by the Monte Carlo model. Imperfections in the manufacturing of the collimators may explain the observed discrepancy. (author)

Disorders of the origin of the suspensory ligament: A diagnostic challenge

International Nuclear Information System (INIS)

Lischer, Ch.J.; Bischofberger, A.S.; Fürst, A.; Lang, J.; Ueltschi, G.

2006-01-01

Lameness in horses due to pain originating from the proximal metacarpal/metatarsal region remains a diagnostic challenge. In cases of obvious lameness the pain can be localised to this region by diagnostic anaesthesia. Because a variety of disorders can cause lameness in this region different imaging modalities including radiography, ultrasonography and scintigraphy should be used to arrive at an accurate diagnosis. Even though a precise anatomic-pathologic diagnosis can still be an enigma, because not only bone and joints, but also soft tissue structures including the proximal suspensory ligament, its origin at the proximal metacarpus/metatarsus, its fascia, the superficial fascia, as well as the intermetacarpal/metatarsal ligaments, the accessory ligament of the deep digital flexor tendon and both digital flexor tendons may be involved. Magnet resonance tomography (MRT) shows a high diagnostic sensitivity in imaging soft tissue structures and bone. In horses MRT is still at the beginning. The MRT appearance of the proximal metacarpal/metatarsal region has not yet been evaluated in detail and there are only few anatomic studies of the origin of the suspensory ligament in horses. The first experiences showed, that more gross and histologic examinations are necessary to fully interpret MRT-images and to differentiate pathologic alterations from clinically not relevant variations [de

Cognitive strategies in the mental rotation task revealed by EEG spectral power.

Science.gov (United States)

Gardony, Aaron L; Eddy, Marianna D; Brunyé, Tad T; Taylor, Holly A

2017-11-01

The classic mental rotation task (MRT; Shepard & Metzler, 1971) is commonly thought to measure mental rotation, a cognitive process involving covert simulation of motor rotation. Yet much research suggests that the MRT recruits both motor simulation and other analytic cognitive strategies that depend on visuospatial representation and visual working memory (WM). In the present study, we investigated cognitive strategies in the MRT using time-frequency analysis of EEG and independent component analysis. We scrutinized sensorimotor mu (µ) power reduction, associated with motor simulation, parietal alpha (pα) power reduction, associated with visuospatial representation, and frontal midline theta (fmθ) power enhancement, associated with WM maintenance and manipulation. µ power increased concomitant with increasing task difficulty, suggesting reduced use of motor simulation, while pα decreased and fmθ power increased, suggesting heightened use of visuospatial representation processing and WM, respectively. These findings suggest that MRT performance involves flexibly trading off between cognitive strategies, namely a motor simulation-based mental rotation strategy and WM-intensive analytic strategies based on task difficulty. Flexible cognitive strategy use may be a domain-general cognitive principle that underlies aptitude and spatial intelligence in a variety of cognitive domains. We close with discussion of the present study's implications as well as future directions. Published by Elsevier Inc.

Effects of white noise on Callsign Acquisition Test and Modified Rhyme Test scores.

Science.gov (United States)

Blue-Terry, Misty; Letowski, Tomasz

2011-02-01

The Callsign Acquisition Test (CAT) is a speech intelligibility test developed by the US Army Research Laboratory. The test has been used to evaluate speech transmission through various communication systems but has not been yet sufficiently standardised and validated. The aim of this study was to compare CAT and Modified Rhyme Test (MRT) performance in the presence of white noise across a range of signal-to-noise ratios (SNRs). A group of 16 normal-hearing listeners participated in the study. The speech items were presented at 65 dB(A) in the background of white noise at SNRs of -18, -15, -12, -9 and -6 dB. The results showed a strong positive association (75.14%) between the two tests, but significant differences between the CAT and MRT absolute scores in the range of investigated SNRs. Based on the data, a function to predict CAT scores based on existing MRT scores and vice versa was formulated. STATEMENT OF RELEVANCE: This work compares performance data of a common speech intelligibility test (MRT) with a new test (CAT) in the presence of white noise. The results here can be used as a part of the standardisation procedures and provide insights to the predictive capabilities of the CAT to quantify speech intelligibility communication in high-noise military environments.

Inflammatory muscle diseases (myositis); Entzuendliche Muskelerkrankungen (Myositiden)

Energy Technology Data Exchange (ETDEWEB)

Vahlensieck, M. [Praxisnetz Radiologie und Nuklearmedizin Bonn Bad Godesberg Rhein Sieg, Bonn (Germany)

2017-12-15

Inflammatory muscle diseases are quite heterogeneous and frequently a specific diagnosis is not easy. Magnetic resonance imaging (MRI) is best suited to demonstrate pattern and size of inflamed muscles. Sensitivity of MRI in showing inflamed muscles is nearly 100%. Specificity, however, is much lower. In cases of suspected bacterial myositis, sonography may be used to exclude abscess formation prior to MRI for more precise information about inflamed muscles. (orig.) [German] Entzuendliche Muskelerkrankungen stellen eine heterogene Gruppe dar und sind mitunter nur schwer exakt zu diagnostizieren. Die Magnetresonanztomographie (MRT) stellt Ausdehnung und Befallsmuster am besten dar. Der Nachweis entzuendlicher Oedeme oder von Einschmelzungen gelingt mit der MRT in annaehernd 100 % der Faelle. Die Spezifitaet der Methode ist allerdings deutlich geringer. Bei Verdacht auf bakterielle Myositiden kommt erst die Sonographie zum Ausschluss von Einschmelzungen und dann die MRT zum Einsatz. (orig.)

On the BER and capacity analysis of MIMO MRC systems with channel estimation error

KAUST Repository

Yang, Liang

2011-10-01

In this paper, we investigate the effect of channel estimation error on the capacity and bit-error rate (BER) of a multiple-input multiple-output (MIMO) transmit maximal ratio transmission (MRT) and receive maximal ratio combining (MRC) systems over uncorrelated Rayleigh fading channels. We first derive the ergodic (average) capacity expressions for such systems when power adaptation is applied at the transmitter. The exact capacity expression for the uniform power allocation case is also presented. Furthermore, to investigate the diversity order of MIMO MRT-MRC scheme, we derive the BER performance under a uniform power allocation policy. We also present an asymptotic BER performance analysis for the MIMO MRT-MRC system with multiuser diversity. The numerical results are given to illustrate the sensitivity of the main performance to the channel estimation error and the tightness of the approximate cutoff value. © 2011 IEEE.

Application of a Steady Meandering River with Piers Using a Lattice Boltzmann Sub-Grid Model in Curvilinear Coordinate Grid

Directory of Open Access Journals (Sweden)

Liping Chen

2018-05-01

Full Text Available A sub-grid multiple relaxation time (MRT lattice Boltzmann model with curvilinear coordinates is applied to simulate an artificial meandering river. The method is based on the D2Q9 model and standard Smagorinsky sub-grid scale (SGS model is introduced to simulate meandering flows. The interpolation supplemented lattice Boltzmann method (ISLBM and the non-equilibrium extrapolation method are used for second-order accuracy and boundary conditions. The proposed model was validated by a meandering channel with a 180° bend and applied to a steady curved river with piers. Excellent agreement between the simulated results and previous computational and experimental data was found, showing that MRT-LBM (MRT lattice Boltzmann method coupled with a Smagorinsky sub-grid scale (SGS model in a curvilinear coordinates grid is capable of simulating practical meandering flows.

Tumor-like diseases of the knee joint; Tumoraehnliche Erkrankungen im Kniegelenk

Energy Technology Data Exchange (ETDEWEB)

Freyschmidt, J. [Klinikum Bremen-Mitte, Beratungsstelle und Referenzzentrum fuer Osteoradiologie, Bremen (Germany)

2012-11-15

Radiological diagnostics of tumor-like lesions of the knee joint. Magnetic resonance imaging (MRI), computed tomography (CT) and X-ray imaging. Up to now there have been no studies regarding sensitivity and specificity of the various diagnostic tools (MRI, CT, X-ray) for the visualization of soft tissue tumors of the knee. The method of first choice for detecting soft tissue tumors and tumor-like lesions in the knee joint is MRI. (orig.) [German] Radiologische Diagnostik tumoraehnlicher Laesionen im Kniegelenk. Eingesetzte Verfahren sind die MRT, CT und Projektionsradiographie. Da es sich um Weichteiltumoren handelt, ist die MRT bei der Diagnostik dominierend. Sensitivitaet und Spezifitaet sind unserer Kenntnis nach bisher nicht untersucht worden. In manchen Faellen werden jedoch noch zusaetzliche Roentgen- oder CT-Bilder benoetigt. Bei Verdacht auf einen Tumor im Kniegelenk wird als erste Untersuchung eine MRT empfohlen. (orig.)

Music and Artistic Artefacts: Symbols of Rohingya Identity and Everyday Resistance in Borderlands

Directory of Open Access Journals (Sweden)

Kazi Fahmida Farzana

2011-01-01

Full Text Available This study looks at the creation of music and art by Rohingya refugees in Bangladesh as a symbol of social resistance and identity. Ethnographic research on the Rohingyas’ use of music and art suggests that these non-conventional means play an important role in communicating their coherent identity and expressing their resistance to the discrimination and oppression experienced in their country of origin as well as in their exile in Bangladesh. This informal resistance is used to keep their memory alive, to transmit that history through verbal and visual expressions to the new generations, and to communicate information about themselves to outsiders. This article posits that these forms of expression, while suggestive of their identity and everyday resistance, occur mostly in an informal and indirect form, rather than in direct confrontation and protest. These informal means also reflect the Rohingyas’ pragmatism and coping strategies for living in the borderlands. ----- Die vorliegende Studie untersucht die Bedeutung der Musik und Kunst der Rohingya-Flüchtlinge in Bangladesch als Symbole sozialen Widerstands und Ausdruck ihrer Identität. Ethnographische Forschungen zur Rohingya-Musik und -Kunst lassen darauf schließen, dass diese nicht-konventionellen Mittel eine wichtige Rolle bei der Vermittlung ihrer kohärenten Identität spielen und ihren Widerstand gegen Diskriminierung und Unterdrückung in ihrem Herkunftsland als auch im Exil in Bangladesch ausdrücken. Der informelle Widerstand wird dazu verwendet ihre Erinnerung lebendig zu halten, ihre Geschichte mittels verbaler und visueller Ausdrucksformen weiterzugeben sowie mit der jungen Generation und Außenstehenden Informationen über sich selbst zu teilen. Der Artikel postuliert, dass diese Ausdrucksformen – wenngleich suggestiv in ihrer Identität und im alltäglichen Widerstand – meist in informeller und indirekter Form auftreten und nicht mittels direkter Konfrontation und

Wertigkeit der Schnittbilddiagnostik in der Evaluation des pädiatrischen Schädel-Hirn-Traumas

OpenAIRE

Schäffeler, Christoph

2010-01-01

Die vorliegende Arbeit untersucht die diagnostische Wertigkeit von Computertomographie (CT) und Magnetresonanztomographie (MRT) in der Diagnostik des pädiatrischen Schädel-Hirn-Traumas. In einer retrospektiven Auswertung der Bildgebung von 64 Patienten im Alter von 0-15 Jahren wurden die Vor- und Nachteile der CT und MRT - Diagnostik bei der Darstellung intrakranieller Traumfolgen herausgearbeitet. Die Ergebnisse räumen der CT weiterhin einen hohen Stellenwert in der Akutdiagnostik ein, zeige...

Specific DNA Binding of a Potential Transcriptional Regulator, Inosine 5′-Monophosphate Dehydrogenase-Related Protein VII, to the Promoter Region of a Methyl Coenzyme M Reductase I-Encoding Operon Retrieved from Methanothermobacter thermautotrophicus Strain ΔH▿

OpenAIRE

Shinzato, Naoya; Enoki, Miho; Sato, Hiroaki; Nakamura, Kohei; Matsui, Toru; Kamagata, Yoichi

2008-01-01

Two methyl coenzyme M reductases (MCRs) encoded by the mcr and mrt operons of the hydrogenotrophic methanogen Methanothermobacter thermautotrophicus ΔH are expressed in response to H2 availability. In the present study, cis elements and trans-acting factors responsible for the gene expression of MCRs were investigated by using electrophoretic mobility shift assay (EMSA) and affinity particle purification. A survey of their operator regions by EMSA with protein extracts from mrt-expressing cul...

Morphologische Qualitätsmerkmale der Mäuseeizelle und deren Zusammenhang mit einer Fehlverteilung des Chromosoms 16

OpenAIRE

Rogge, Sabine

2009-01-01

Eizellen der Maus wurden nach lichtmikroskopischen Kriterien bewertet. Mittels Fluoreszenz- in- situ- Hybridisierung wurden zudem meiotische Fehlverteilungen des Chromosom 16 der Maus 16 dargestellt. Die Korrelation zwischen morphologischen Kriterien und chromosomaler Fehlverteilung wurde untersucht.

GPS-gestützte Beikrautregulierung im Freilandgemüsebau

Directory of Open Access Journals (Sweden)

Hans-Peter Schwarz

2014-04-01

Full Text Available Im Freilandgemüsebau sollen einerseits qualitativ hochwertige Produkte erzeugt werden, die frei von Pflanzenschutzmittelrückständen und unerwünschtem Beikrautbesatz sind, andererseits nehmen Indikationslücken bei Herbiziden zu oder die Mittel können unerwünschte Rückstände verursachen. Zunehmend werden daher mechanische Verfahren zur Beikrautregulierung verwendet. Diese sind jedoch sehr zeitaufwendig und somit kostenintensiv. Ob die moderne GPS-Technologie die mechanische Beikrautregulierung unterstützen und optimieren kann, sollte in einer Masterthesis an der Hochschule Geisenheim geklärt werden. Die praktischen Untersuchungen führten zu dem Ergebnis, dass die Beikrautregulierung mittels GPS-Steuerung der Maschinen und Geräte nicht nur schneller, sondern auch kostengünstiger und präziser durchgeführt werden kann.

Optimal low-dispersion low-dissipation LBM schemes for computational aeroacoustics

OpenAIRE

Xu, Hui; Sagaut, Pierre

2011-01-01

Lattice Boltmzmann Methods (LBM) have been proved to be very effective methods for computational aeroacoustics (CAA), which have been used to capture the dynamics of weak acoustic fluctuations. In this paper, we propose a strategy to reduce the dispersive and disspative errors of the two-dimensional (2D) multi-relaxation-time lattice Boltzmann method (MRT-LBM). By presenting an effective algorithm, we obtain a uniform form of the linearized Navier-Stokes equations corresponding to the MRT-LBM...

2D radiation-magnetohydrodynamic simulations of SATURN imploding Z-pinches

International Nuclear Information System (INIS)

Hammer, J.H.; Eddleman, J.L.; Springer, P.T.

1995-01-01

Z-pinch implosions driven by the SATURN device at Sandia National Laboratory are modeled with a 2D radiation magnetohydrodynamic (MHD) code, showing strong growth of magneto-Rayleigh Taylor (MRT) instability. Modeling of the linear and nonlinear development of MRT modes predicts growth of bubble-spike structures that increase the time span of stagnation and the resulting x-ray pulse width. Radiation is important in the pinch dynamics keeping the sheath relatively cool during the run-in and releasing most of the stagnation energy. The calculations give x-ray pulse widths and magnitudes in reasonable agreement with experiments, but predict a radiating region that is too dense and radially localized at stagnation. We also consider peaked initial density profiles with constant imploding sheath velocity that should reduce MRT instability and improve performance. 2D krypton simulations show an output x-ray power > 80 TW for the peaked profile

'Charles River Associates analysis : impact of the world implementing the Kyoto Protocol : analysis of the impact on the Canadian upstream oil and gas industry of the global implementation of the Kyoto Protocol

International Nuclear Information System (INIS)

1999-09-01

A study was conducted to estimate the impacts on the Canadian oil and gas industry from the changes in demand for oil and natural gas fuels caused by implementation of the Kyoto Protocol throughout the Canadian economy. The multi-sector, multi-region trade (MS-MRT) model was used in the study. The MS-MRT was designed to study the effects of carbon restrictions on industrial output, trade and economic welfare in different regions of the world. An overview of the model was presented. The regions in the MS-MRT model are divided as follows: Canada; United States; European Union; Other OECD; Eastern Europe and Former Soviet Union; Non-OECD Asia; Mexico and OPEC; and all other countries. This paper also described how production, consumption and trade are modelled. The cases under which the impacts on the Canadian oil and gas sectors are modelled were also presented. refs., tabs., figs

Electrothermal instability growth in magnetically driven pulsed power liners

International Nuclear Information System (INIS)

Peterson, Kyle J.; Sinars, Daniel B.; Yu, Edmund P.; Herrmann, Mark C.; Cuneo, Michael E.; Slutz, Stephen A.; Smith, Ian C.; Atherton, Briggs W.; Knudson, Marcus D.; Nakhleh, Charles

2012-01-01

This paper explores the role of electro-thermal instabilities on the dynamics of magnetically accelerated implosion systems. Electro-thermal instabilities result from non-uniform heating due to temperature dependence in the conductivity of a material. Comparatively little is known about these types of instabilities compared to the well known Magneto-Rayleigh-Taylor (MRT) instability. We present simulations that show electrothermal instabilities form immediately after the surface material of a conductor melts and can act as a significant seed to subsequent MRT instability growth. We also present the results of several experiments performed on Sandia National Laboratories Z accelerator to investigate signatures of electrothermal instability growth on well characterized initially solid aluminum and copper rods driven with a 20 MA, 100 ns risetime current pulse. These experiments show excellent agreement with electrothermal instability simulations and exhibit larger instability growth than can be explained by MRT theory alone.

Secondary Breast Cancer Risk by Radiation Volume in Women With Hodgkin Lymphoma

Energy Technology Data Exchange (ETDEWEB)

Conway, Jessica L. [Centre for Lymphoid Cancer, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Department of Surgery, University of British Columbia, Vancouver, British Columbia (Canada); Connors, Joseph M. [Centre for Lymphoid Cancer, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Tyldesley, Scott [Centre for Lymphoid Cancer, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Department of Surgery, University of British Columbia, Vancouver, British Columbia (Canada); Savage, Kerry J. [Centre for Lymphoid Cancer, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Campbell, Belinda A. [Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia); Zheng, Yvonne Y.; Hamm, Jeremy [Department of Cancer Surveillance and Outcomes, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Pickles, Tom, E-mail: TPickles@bccancer.bc.ca [Centre for Lymphoid Cancer, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Department of Surgery, University of British Columbia, Vancouver, British Columbia (Canada)

2017-01-01

Purpose: To determine whether the risk of secondary breast cancer (SBC) is reduced in women with Hodgkin lymphoma (HL) treated with smaller field radiation therapy (SFRT) versus mantle field radiation therapy (MRT). Methods and Materials: We used the BC Cancer Agency (BCCA) Lymphoid Cancer Database to identify female patients treated for HL between January 1961 and December 2009. Radiation therapy volumes were categorized as MRT or SFRT, which included involved field, involved site, or involved nodal radiation therapy. SBC risk estimates were compared using competing risk analysis and Fine and Gray multivariable model: MRT ± chemotherapy, SFRT ± chemotherapy, or chemotherapy-only. Results: Of 734 eligible patients, 75% of the living patients have been followed up for more than 10 years, SBC has developed in 54, and 15 have died of breast cancer. The 20-year estimated risks (competing risk cumulative incidence) for SBC differed significantly: MRT 7.5% (95% confidence interval [CI] 4.4%-11.5%), SFRT 3.1% (95% CI 1.0%-7.7%), and chemotherapy-only 2.2% (95% CI 1.0%-4.8%) (P=.01). Using a Fine and Gray model to control for death and patients lost to follow-up, MRT was associated with a higher risk of SBC (hazard ratio [HR] = 2.9; 95% CI 1.4%-6.0%; P=.004) compared with chemotherapy-only and with SFRT (HR = 3.3; 95% CI 1.3%-8.4%; P=.01). SFRT was not associated with a greater risk of SBC compared with chemotherapy-only (HR = 0.87; 95% CI 0.28%-2.66%; P=.80). Conclusion: This study confirms that large-volume MRT is associated with a markedly increased risk of SBC; however, more modern small-volume RT is not associated with a greater risk of SBC than chemotherapy alone.

Simulation of turbulent flow over staggered tube bundles using multi-relaxation time lattice Boltzmann method

International Nuclear Information System (INIS)

Park, Jong Woon; Choi, Hyun Gyung

2014-01-01

A turbulent fluid flow over staggered tube bundles is of great interest in many engineering fields including nuclear fuel rods, heat exchangers and especially a gas cooled reactor lower plenum. Computational methods have evolved for the simulation of such flow for decades and lattice Boltzmann method (LBM) is one of the attractive methods due to its sound physical basis and ease of computerization including parallelization. In this study to find computational performance of the LBM in turbulent flows over staggered tubes, a fluid flow analysis code employing multi-relaxation time lattice Boltzmann method (MRT-LBM) is developed based on a 2-dimensional D2Q9 lattice model and classical sub-grid eddy viscosity model of Smagorinsky. As a first step, fundamental performance MRT-LBM is investigated against a standard problem of a flow past a cylinder at low Reynolds number in terms of drag forces. As a major step, benchmarking of the MRT-LBM is performed over a turbulent flow through staggered tube bundles at Reynolds number of 18,000. For a flow past a single cylinder, the accuracy is validated against existing experimental data and previous computations in terms of drag forces on the cylinder. Mainly, the MRT-LBM computation for a flow through staggered tube bundles is performed and compared with experimental data and general purpose computational fluid dynamic (CFD) analyses with standard k-ω turbulence and large eddy simulation (LES) equipped with turbulence closures of Smagrinsky-Lilly and wall-adapting local eddy-viscosity (WALE) model. The agreement between the experimental and the computational results from the present MRT-LBM is found to be reasonably acceptable and even comparable to the LES whereas the computational efficiency is superior. (orig.)

Simulation of turbulent flow over staggered tube bundles using multi-relaxation time lattice Boltzmann method

Energy Technology Data Exchange (ETDEWEB)

Park, Jong Woon; Choi, Hyun Gyung [Dongguk Univ., Gyeongju (Korea, Republic of). Nuclear and Energy Engineering Dept.

2014-02-15

A turbulent fluid flow over staggered tube bundles is of great interest in many engineering fields including nuclear fuel rods, heat exchangers and especially a gas cooled reactor lower plenum. Computational methods have evolved for the simulation of such flow for decades and lattice Boltzmann method (LBM) is one of the attractive methods due to its sound physical basis and ease of computerization including parallelization. In this study to find computational performance of the LBM in turbulent flows over staggered tubes, a fluid flow analysis code employing multi-relaxation time lattice Boltzmann method (MRT-LBM) is developed based on a 2-dimensional D2Q9 lattice model and classical sub-grid eddy viscosity model of Smagorinsky. As a first step, fundamental performance MRT-LBM is investigated against a standard problem of a flow past a cylinder at low Reynolds number in terms of drag forces. As a major step, benchmarking of the MRT-LBM is performed over a turbulent flow through staggered tube bundles at Reynolds number of 18,000. For a flow past a single cylinder, the accuracy is validated against existing experimental data and previous computations in terms of drag forces on the cylinder. Mainly, the MRT-LBM computation for a flow through staggered tube bundles is performed and compared with experimental data and general purpose computational fluid dynamic (CFD) analyses with standard k-ω turbulence and large eddy simulation (LES) equipped with turbulence closures of Smagrinsky-Lilly and wall-adapting local eddy-viscosity (WALE) model. The agreement between the experimental and the computational results from the present MRT-LBM is found to be reasonably acceptable and even comparable to the LES whereas the computational efficiency is superior. (orig.)

Low ambient temperature elevates plasma triiodothyronine concentrations while reducing digesta mean retention time and methane yield in sheep.

Science.gov (United States)

Barnett, M C; McFarlane, J R; Hegarty, R S

2015-06-01

Ruminant methane yield (MY) is positively correlated with mean retention time (MRT) of digesta. The hormone triiodothyronine (T3 ), which is negatively correlated with ambient temperature, is known to influence MRT. It was hypothesised that exposing sheep to low ambient temperatures would increase plasma T3 concentration and decrease MRT of digesta within the rumen of sheep, resulting in a reduction of MY. To test this hypothesis, six Merino sheep were exposed to two different ambient temperatures (cold treatment, 9 ± 1 °C; warm control 26 ± 1 °C). The effects on MY, digesta MRT, plasma T3 concentration, CO2 production, DM intake, DM digestibility, change in body weight (BW), rumen volatile fatty acid (VFA) concentrations, estimated microbial protein output, protozoa abundance, wool growth, water intake, urine output and rectal temperature were studied. Cold treatment resulted in a reduction in MY (p < 0.01); digesta MRT in rumen (p < 0.01), hindgut (p = 0.01) and total digestive tract (p < 0.01); protozoa abundance (p < 0.05); and water intake (p < 0.001). Exposure to cold temperature increased plasma T3 concentration (p < 0.05), CO2 production (p = 0.01), total VFA concentrations (p = 0.03) and estimated microbial output from the rumen (p = 0.03). The rate of wool growth increased (p < 0.01) due to cold treatment, but DM intake, DM digestibility and BW change were not affected. The results suggest that exposure of sheep to cold ambient temperatures reduces digesta retention time in the gastrointestinal tract, leading to a reduction in enteric methane yield. Further research is warranted to determine whether T3 could be used as an indirect selection tool for genetic selection of low enteric methane-producing ruminants. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

A Multi-Scale Validation Strategy for Albedo Products over Rugged Terrain and Preliminary Application in Heihe River Basin, China

Directory of Open Access Journals (Sweden)

Xingwen Lin

2018-01-01

Full Text Available The issue for the validation of land surface remote sensing albedo products over rugged terrain is the scale effects between the reference albedo measurements and coarse scale albedo products, which is caused by the complex topography. This paper illustrates a multi-scale validation strategy specified for coarse scale albedo validation over rugged terrain. A Mountain-Radiation-Transfer-based (MRT-based albedo upscaling model was proposed in the process of multi-scale validation strategy for aggregating fine scale albedo to coarse scale. The simulated data of both the reference coarse scale albedo and fine scale albedo were used to assess the performance and uncertainties of the MRT-based albedo upscaling model. The results showed that the MRT-based model could reflect the albedo scale effects over rugged terrain and provided a robust solution for albedo upscaling from fine scale to coarse scale with different mean slopes and different solar zenith angles. The upscaled coarse scale albedos had the great agreements with the simulated coarse scale albedo with a Root-Mean-Square-Error (RMSE of 0.0029 and 0.0017 for black sky albedo (BSA and white sky albedo (WSA, respectively. Then the MRT-based model was preliminarily applied for the assessment of daily MODerate Resolution Imaging Spectroradiometer (MODIS Albedo Collection V006 products (MCD43A3 C6 over rugged terrain. Results showed that the MRT-based model was effective and suitable for conducting the validation of MODIS albedo products over rugged terrain. In this research area, it was shown that the MCD43A3 C6 products with full inversion algorithm, were generally in agreement with the aggregated coarse scale reference albedos over rugged terrain in the Heihe River Basin, with the BSA RMSE of 0.0305 and WSA RMSE of 0.0321, respectively, which were slightly higher than those over flat terrain.

Development of new heterogeneous catalysts for the decomposition of methanol into hydrogen and carbon monoxide applying high throughput methods; Entwicklung neuer heterogener Katalysatoren zur Spaltung von Methanol in Wasserstoff und Kohlenmonoxid mittels Hochdurchsatz-Methoden

Energy Technology Data Exchange (ETDEWEB)

Weiss, Torsten

2008-07-11

The topic of this thesis has been the development of new heterogeneous catalysts for the decomposition of methanol into hydrogen and carbon monoxide. As an important constraint here, the content of noble metals of the catalysts should be as low as possible. High-throughput-methods were applied in some of the syntheses and experiments to accelerate the development, as, for example, the use of liquid based sol-gel syntheses and the examination of catalyst libraries by spatial resolution gas chromatography. This screening technique allowed to test up to 207 different substances during one single experiment. Then, different combinatorial strategies were applied. First, these methods led to a highly active and stable catalyst in the ternary system of Cu-Ni-Zn, which showed high conversion and selectivity comparable to an industrial reference catalyst. Its activity during an 18 hour long term run was constant in contrast to the reference. Second, an additional approach starting from a broader variety of elements led to a Ce- Ru- and to a Cr-Ru-catalyst. Both of them were highly active in short term experiments, but lost their outstanding performances during long term runs. (orig.) [German] Die vorliegende Arbeit befasste sich mit der Entwicklung neuer heterogener Katalysatoren fuer die Spaltung von Methanol zu Wasserstoff und Kohlenmonoxid, die einen moeglichst geringen Gehalt an Edelmetallen aufweisen sollten. Um diesen Prozess zu beschleunigen, wurden in einem Teil der Synthesen und Experimente Hochdurchsatzmethoden verwendet. Neben der Roboter gestuetzten Sol-Gel-Synthese umfasste dies die Untersuchung von Katalysatorbibliotheken mittels ortsaufgeloester Gaschromatographie, die es ermoeglichte, in einem Experiment bis zu 207 verschiedene Substanzen auf ihre katalytische Aktivitaet zu testen. Unter Anwendung verschiedener kombinatorischer Strategien wurde zunaechst ein sehr aktiver und stabiler Katalysator im ternaeren Cu-Ni-Zn-System entdeckt. Neben Umsaetzen und

Performance analysis for optimum transmission and comparison with maximal ratio transmission for MIMO systems with cochannel interference

Directory of Open Access Journals (Sweden)

Lin Sheng-Chou

2011-01-01

Full Text Available Abstract This article presents the performance analysis of multiple-input/multiple-output (MIMO systems with quadrature amplitude modulation (QAM transmission in the presence of cochannel interference (CCI in nonfading and flat Rayleigh fading environments. The use of optimum transmission (OT and maximum ratio transmission (MRT is considered and compared. In addition to determining precise results for the performance of QAM in the presence of CCI, it is our another aim in this article to examine the validity of the Gaussian interference model in the MRT-based systems. Nyquist pulse shaping and the effects of cross-channel intersymbol interference produced by CCI due to random symbol of the interfering signals are considered in the precise interference model. The error probability for each fading channel is estimated fast and accurately using Gauss quadrature rules which can approximate the probability density function (pdf of the output residual interference. The results of this article indicate that Gaussian interference model may overestimate the effects of interference, particularly, for high-order MRT-based MIMO systems over fading channels. In addition, OT cannot always outperform MRT due to the significant noise enhancement when OT intends to cancel CCI, depending on the combination of the antennas at the transmitter and the receiver, number of interference and the statistical characteristics of the channel.

Rehabilitation of Aphasia: application of the Melodic-Rhythmic Therapy to the Italian Language

Directory of Open Access Journals (Sweden)

Maria Daniela eCortese

2015-09-01

Full Text Available Aphasia is a complex disorder, frequent after stroke (~38%, with a detailed pathophysiological characterization. Proper approaches are mandatory to devise an efficient rehabilitative strategy, in order to address the everyday life and professional disability. Several rehabilitative procedures are based on psycholinguistic, cognitive, psychosocial or pragmatic approaches, among these with neurobehavioral ratio, the Melodic Intonation Therapy (MIT .Van Eeckhout’s adaptation to the French language (Melodic-Rhythmic Therapy: MRT has implemented the training strategy by adding a rhythmic structure reproducing the French prosody.Purposes of this study were to adapt the MRT rehabilitation procedures to the Italian language and to verify its efficacy in a group of 6 chronic patients (5 males with severe non-fluent aphasia and without specific aphasic treatments at least from 9 months. The patients were treated 4 days a week for 16 weeks, with sessions of 30-40 min. They were assessed 6 months after the end of the treatment (follow-up. The patients showed a significant improvement at the Aachener Aphasie Test in different fields of spontaneous speech, with superimposable results at the follow-up. Albeit preliminary, these findings support the use of MRT in the rehabilitation after stroke. Specifically, MRT seems to benefit from its stronger structure than the available stimulation-facilitation procedures and allows a better quantification of the rehabilitation efficacy.

Green Infrastructure Concept for JABODETABEKJUR Metropolitan Area

Science.gov (United States)

Tanuwidjaja, Gunawan; Gates Chang, Bill

2017-07-01

Sixty “Mega Cities” would emerge by 2015 catering of 600 million populations, and were threatened by the climate change, because of cyclones, flooding, etc. Jakarta became a metro region covering Jakarta, Bogor, Tangerang, Bekasi, Depok and Cianjur. Jakarta metropolitan faced the very high population growth, urban sprawling, traffic jams, flooding, green open space reduction, environmental degradation, urban slums and illegal street hawkers. Flooding and traffic congestions were the two most important issues to solve. SWOT analysis and urban design solutions were produced to create a sustainable solution. Related to transportation issues, Singapore Mass Rapid Transport (MRT) concept was evaluated. Meanwhile the Netherlands’ polder concept as well as Singapore’s Integrated Water Management were also analyzed. The development of above ground MRT as well as Busway could be developed to connect Jakarta Metropolitan Region. The networks were developed on the main toll road networks. The MRT and Busway would eventually replace the need of automobile use in the future. The Transit - Oriented - Development (TOD) with high density can be suggested to be concentrated nearby the MRT and Busway interchange stations. The Netherlands’ polder and were adopted for urban’ low-lying lands in Jakarta Metropolitan Region, A polder system was defined as the Integrated Man-made Drainage System consisting Dikes, Drains, Retention Ponds, Outfall Structures or Pumping Stations. The polder system was proposed to be extended to Tangerang and Bekasi area.

Measurements of Magneto-Rayleigh-Taylor instability growth in solid liners on the 20 MA Z facility

International Nuclear Information System (INIS)

Bigman, Verle; Vesey, Roger Alan; Shores, Jonathon; Herrmann, Mark C.; Stamm, Robert; Killebrew, Korbie; Holt, Randy; Blue, Brent; Nakhleh, Charlie; McBride, Ryan D.; Leifeste, Gordon T.; Smith, Ian Craig; Stygar, William A.; Porter, John Larry Jr.; Cuneo, Michael Edward; Bennett, Guy R.; Schroen, Diana Grace; Sinars, Daniel Brian; Lopez, Mike R.; Slutz, Stephen A.; Atherton, Briggs W.; Tomlinson, Kurt; Edens, Aaron D.; Savage, Mark Edward; Peterson, Kyle J.

2010-01-01

The magneto-Rayleigh-Taylor (MRT) instability is the most important instability for determining whether a cylindrical liner can be compressed to its axis in a relatively intact form, a requirement for achieving the high pressures needed for inertial confinement fusion (ICF) and other high energy-density physics applications. While there are many published RT studies, there are a handful of well-characterized MRT experiments at time scales >1 (micro)s and none for 100 ns z-pinch implosions. Experiments used solid Al liners with outer radii of 3.16 mm and thicknesses of 292 (micro)m, dimensions similar to magnetically-driven ICF target designs (1). In most tests the MRT instability was seeded with sinusoidal perturbations (λ = 200, 400 (micro)m, peak-to-valley amplitudes of 10, 20 (micro)m, respectively), wavelengths similar to those predicted to dominate near stagnation. Radiographs show the evolution of the MRT instability and the effects of current-induced ablation of mass from the liner surface. Additional Al liner tests used 25-200 (micro)m wavelengths and flat surfaces. Codes being used to design magnetized liner ICF loads (1) match the features seen except at the smallest scales (<50 (micro)m). Recent experiments used Be liners to enable penetrating radiography using the same 6.151 keV diagnostics and provide an in-flight measurement of the liner density profile.

Inflammatory lesions of the spinal cord and the nerve roots in magnetic resonance imaging; Entzuendliche Erkrankungen des Rueckenmarks und der Nervenwurzeln in der MRT

Energy Technology Data Exchange (ETDEWEB)

Sartoretti-Schefer, S. [Inst. fuer Neuroradiologie, Universitaetsspital Zuerich (Switzerland); Wichmann, W. [Inst. fuer Neuroradiologie, Universitaetsspital Zuerich (Switzerland); Valavanis, A. [Inst. fuer Neuroradiologie, Universitaetsspital Zuerich (Switzerland)

1996-11-01

und immunkompetenten Patienten eingeteilt, was teilweise Rueckschluesse auf die zugrundeliegende Aetiologie erlaubt. Der immunsupprimierte Patient leidet vor allem an viralen (Herpes simplex, Herpes zoster, Zytomegalie, HIV-Virus) sowie an bakteriellen (Tuberkulose, selten Syphilis), aber nur selten an parasitaeren Infektionen. Der immunkompetente Patient erkrankt vor allem an bakteriellen Infektionen (Borreliose) sowie an immunologisch bedingten entzuendlichen Erkrankungen (Sarkoidose) und an demyelinisierenden Laesionen. Haeufig ist auch die idiopathische Myelitis. Virale Infektionen sind selten. Die MRT-Morphologie der entzuendlichen Laesionen wird durch sekundaere ischaemische und demyelinisierende Veraenderungen kompliziert, wodurch die Differentialdiagnose sehr erschwert sein kann, da das gesamte Spektrum von demyelinisierenden bzw. ischaemischen und entzuendlichen Erkrankungen miteinbezogen werden muss. Zudem koennen auch tumoroese Prozesse eine Myelitis bzw. Radikulitis nachahmen. (orig.)

Sensitivity of MRI in detecting alveolar infiltrates. Experimental studies; Sensitivitaet der MRT fuer alveolaere Infiltrate. Experimentelle Untersuchungen

Energy Technology Data Exchange (ETDEWEB)

Biederer, J.; Busse, I.; Grimm, J.; Reuter, M.; Heller, M. [Kiel Univ. (Germany). Klinikum fuer Diagnostische Radiologie; Muhle, C. [Kiel Univ. (Germany). Klinik fuer Nuklearmedizin; Freitag, S. [Kiel Univ. (Germany). Inst. fuer Medizinische Informatik und Statistik

2002-08-01

detect pneumonia in patients. (orig.) [German] Zielsetzung: Eine experimentelle Studie zur Untersuchung des Signalverhaltens artifizieller alveolaerer Infiltrate mit T{sub 1}- und T{sub 2}-gewichteten MR-Sequenzen. Material und Methoden: 10 Lungen-Explantate von Schweinen wurden tracheal intubiert, in der kuenstlichen Thoraxhoehle eines Phantoms durch Unterdruck entfaltet und an einem klinischen Magnetresonanztomographen bei 1,5 T untersucht. Mit gezielter Instillation von 100-200 ml Gelatineloesung wurden alveolaere Infiltrate erzeugt und mit Gradientenecho- (2D-, 3D-GRE) und schnellen Spinechosequenzen (T{sub 2}-TSE, T{sub 2}-HASTE) dargestellt. Die Signalintensitaet des Lungenparenchyms nativ und mit Infiltrat wurde an repraesentativen Querschnitten erfasst. Zum Vergleich erfolgten Kontrollen mit Spiral-CT. Ergebnisse: Die instillierte Fluessigkeit simulierte alveolaere Infiltrate mit typischem Milchglasmuster im CT, wie es an Patienten mit Pneumonie oder ARDS beobachtet wird. Vor dem Versuch zeigten nur T{sub 2}-HASTE und T{sub 2}-TSE ein Lungenparenchymsignal (Signal/Rausch-Verhaeltnis von 3,62 bzw. 1,39). Nach Instillation von Fluessigkeit fand sich in diesen Sequenzen ein Signalanstieg von ca. 30% bei 100 ml (p<0,01) bzw. 60% bei 200 ml (p<0,01). Bei 2D-GRE betrug die Signalintensitaetszunahme 0,74% (p=0,32) nach 100 ml und 5,6% (p<0,01) nach 200 ml (fuer 3D-GRE 2,2% [p=0,02] bzw. 4,4% [p<0,01]). Die CT-Kontrollen zeigten fuer 100 ml eine Dichtezunahme um durchschnittlich 17 H.E. (p=0,02) und fuer 200 ml um 75 H.E. (p<0,01). Schlussfolgerungen: Mit T{sub 2}-gewichteten Sequenzen ist die MRT zur Darstellung artifizieller alveolaerer Infiltrate geeignet. (orig.)

Interaktion mit RFID Ausleih- und Rückgabeautomaten

DEFF Research Database (Denmark)

Greifeneder, Elke; Heyroth, Melanie; Klingbeil, Karin

2011-01-01

Der Artikel untersucht mittels Beobachtung die Interaktion zwischen RFID-Ausleih- und Rückgabeautomaten sowie Bibliotheksbenutzern in vier deutschen Bibliotheken. Die Ergebnisse belegen, dass die Interaktion grundsätzlich funktioniert. Die Benutzer zeigten Gelassenheit und Routine im Umgang mit den...

Magnetic resonance imaging for early diagnosis of rheumatoid arthritis; Magnetresonanztomographie in der Fruehdiagnostik der rheumatoiden Arthritis

Energy Technology Data Exchange (ETDEWEB)

Uhl, M. [Universitaetsklinik Freiburg (Germany). Abt. fuer Radiologische Diagnostik; Allmann, K.H. [Universitaetsklinik Freiburg (Germany). Abt. fuer Radiologische Diagnostik; Hauer, M.P. [Universitaetsklinik Freiburg (Germany). Abt. fuer Radiologische Diagnostik; Laubenberger, J. [Universitaetsklinik Freiburg (Germany). Abt. fuer Radiologische Diagnostik; Kempis, J. v. [Universitaetsklinik Freiburg (Germany). Abt. fuer Rheumatologie und Klinische Immunologie; Langer, M. [Universitaetsklinik Freiburg (Germany). Abt. fuer Radiologische Diagnostik

1997-06-01

Nuclear magnetic resonance tomography (MRI) represents essential progress in the diagnostic means for evaluation of lesions of the muskuloskeletal system. The imaging of bone joints including material and structures like cartilage, tendons, ligaments, effusions, pannus, cortical bone and marrow offers essential advantages for diagnosis, differential diagnosis, follow-up control and detection of local complications in rheumatics radiology. The review article discusses the achievements of MRI for detection of early signs of rheumatoid arthritis and the current indications for MRI examination for early diagnosis. (Orig./AJ) [Deutsch] Die Magnetresonanztomographie (MRT) ist ein bedeutender Fortschritt in der Diagnostik von Erkrankungen des muskuloskelettalen Systems. Die Darstellung von Gelenkstrukturen einschliesslich Knorpel, Sehnen, Baendern, Erguessen, Pannus, kortikalem Knochen und Mark ist in der Diagnostik, Differentialdiagnostik, Verlaufsbeurteilung und der Aufdeckung von lokalen Komplikationen in der Rheumaradiologie von erheblichem Vorteil. In der Uebersicht werden die Fruehveraenderungen der rheumatoiden Arthritis in der MRT-Bildgebung und die heute aktuellen Indiakationen fuer den Einsatz der MRT in der Fruehdiagnostik diskutiert. (Orig./AJ)

Early and late inhibitions elicited by a peripheral visual cue on manual response to a visual target: Are they based on Cartesian coordinates?

Directory of Open Access Journals (Sweden)

Fábio V. Magalhães

2005-01-01

Full Text Available A non-informative cue (C elicits an inhibition of manual reaction time (MRT to a visual target (T. We report an experiment to examine if the spatial distribution of this inhibitory effect follows Polar or Cartesian coordinate systems. C appeared at one out of 8 isoeccentric (7o positions, the C-T angular distances (in polar coordinates were 0º or multiples of 45º and ISI were 100 or 800ms. Our main findings were: (a MRT was maximal when C- T distance was 0o and minimal when C-T distance was 180o and (b besides an angular distance effect, there is a meridian effect. When C and T occurred in the same quadrant, MRT was longer than when T and C occurred at the same distance (45o but on different sides of vertical or horizontal meridians. The latter finding indicates that the spatial distribution of the cue inhibitory effects is based on a Cartesian coordinate system.

Radiological diagnostics of multiple myeloma; Radiologische Diagnostik des multiplen Myeloms

Energy Technology Data Exchange (ETDEWEB)

D' Anastasi, M.; Grandl, S.; Reiser, M.F.; Baur-Melnyk, A. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany)

2014-06-15

). Projektionsradiographie (Skelettstatus) zur Erfassung von Osteolysen, Osteoporose oder Frakturen. Die Ganzkoerper-CT stellt hochsensitiv die Osteolysen, die Ganzkoerper-MRT das Ausmass der Knochenmarkinfiltration dar. Die Positronenemissionstomographie(PET)-CT kann zusaetzlich die aktiven Myelomlaesionen detektieren und wichtige Informationen fuer den Therapieverlauf geben. Nach den Ergebnissen mehrerer Studien sind die Schnittbildverfahren dem Roentgenskelettstatus ueberlegen. Die Ganzkoerper-MRT ist sowohl fuer den Nachweis fokaler Laesionen als auch einer diffusen Infiltration signifikant sensitiver als die Ganzkoerper-CT. Die PET-CT zeigt eine vergleichbare Sensitivitaet mit der Ganzkoerper-MRT. Aufgrund der hoeheren Sensitivitaet bei der Detektion von Myelomlaesionen sollten die Ganzkoerper-CT und die Ganzkoerper-MRT die Projektionsradiographie ersetzen. Bei Verdacht auf ein MM sollte bei der initialen Diagnostik eine Ganzkoerper-CT durchgefuehrt werden. Werden hier keine Herde gefunden, sollte, falls verfuegbar, eine Ganzkoerper(GK)-MRT oder zumindest eine MRT der Wirbelsaeule und des Beckens durchgefuehrt werden. Falls eine GK-MRT in der initialen Diagnostik durchgefuehrt wurde, sollte bei fokalen Herden eine ergaenzende Ganzkoerper-CT erfolgen, um das Ausmass der Osteolysen zu erfassen und das Frakturrisiko abzuschaetzen. Bei der monoklonalen Gammopathie unklarer Signifikanz (MGUS), beim solitaeren und beim ''smoldering'' Myelom sollte, falls verfuegbar, die GK-MRT eingesetzt werden, da hiervon die Prognose und das Therapiekonzept bei vorhandenen Infiltraten betroffen sind. (orig.)

Hydroaggregat

Science.gov (United States)

Heinen, Frank; Eberspächer, Peter

Das Hydroaggregat/Modulator bildet die hydraulische Verbindung zwischen dem Hauptzylinder und den Radzylindern und ist damit zentrales Bauelement elektronischer Bremssysteme. Es setzt die Stellbefehle des Steuergeräts um und regelt mittels Magnetventilen die Drücke in den Radbremsen.

MRT of abdomen and pelvis. 2. tot. rev. and enl. ed.; MRT von Abdomen und Becken

Energy Technology Data Exchange (ETDEWEB)

Hamm, B.; Krestin, G.P. (eds.); Laniado, M.; Nicolas, V.; Taupitz, M.

2007-07-01

The book offers maximum expert knowledge from an experienced team of authors, first-class reference image material, clear guidelines for indications and actions also in comparison with other techniques, and a detailed presentation of examination sequences with table protocols. There are clear schematic drawings, guidelines, key findings and tables for differential diagnosis, and a list of possible misinterpretations. The authors present contributions on MR angiography and examination of infants and take account of all modern trends and indications. The book facilitates introduction to the subject, reading-up, and quick reference. It provides practical support at the workplace and is written in a user-friendly manner. There is a new chapter ''rectum'', and the book contains more than 1000 illustrations. (orig.)

CT and MRT in mediastinal and hilar masses. CT und MRT bei mediastinalen und hilaeren Raumforderungen

Energy Technology Data Exchange (ETDEWEB)

Prayer, L.; Kramer, J.; Stiglbauer, R.; Wimberger, D.; Imhof, H. (Vienna Univ. (Austria). Klinik fuer Radiodiagnostik Ludwig-Boltzmann-Institut fuer Radiologisch-Physikalische Tumordiagnostik, Vienna (Austria)); Metz, V. (Vienna Univ. (Austria). 2. Chirurgische Klinik)

1990-11-01

Thirty-eight patients with mediastinal and/or hilar masses were imaged by computed tomography (CT) and magnetic resonance imaging (MRI). Results were analyzed retrospectively regarding the ability to demonstrate the masses, their number, size, definition, location and tissue characteristics. CT and MRI showed equivalent results in 32 cases; additional information was obtained in two patients by CT, in four patients by MRI. In view of the specific advantages and limitations of both CT and MRI we believed that in patients with mediastinal and/or hilar masses, contrast enhanced CT remains the procedure of choice after performing plain chest radiographs; in certain cases MRI will prove useful for further evaluation. (orig.).

Radiological diagnostics of birth trauma in newborns

Directory of Open Access Journals (Sweden)

Юрій Анатолійович Коломійченко

2015-10-01

Full Text Available Aim of the work. To analyze indices of the different radiological methods and to compare it.Materials and methods. The newborns with spinal trauma (n=33 were analyzed, the children who have been excluded this diagnosis (n=27 formed the control group. All children underwent the radiography of cervical spine, the part of them – MRT and USG. There was carried out the visual assessment and analysis of metrical indices.Results. Patients were separated into groups of heaviness, 16 patients with slight degree, 10 with middle one and 7 with heavy degree of injury. At all methods the width of the Cruveilhier joint fissure in children with an injury of upper cervical spine reliably (р<0,001 differs from the one in the control group, and was detected the moderate correlation (r>0,4.When using radiology and MRT in children with traumatic injures the width of prevertebral soft tissues was reliably more and the degree of reliability was higher at radiology (р<0,001, than at MRT (р<0,01. The correlations between the width of soft tissues and the degree of heaviness were detected at all levels at radiography and only at the level C1 at MRT.Conclusions. An analysis demonstrated the different degree of importance of some indices for detecting injuries of the upper cervical spine in newborns. There was also proved that the metrical data of the different methods not reliably differ

Temperature mapping of laser-induced hyperthermia in an ocular phantom using magnetic resonance thermography.

Science.gov (United States)

Maswadi, Saher M; Dodd, Stephen J; Gao, Jia-Hong; Glickman, Randolph D

2004-01-01

Laser-induced heating in an ocular phantom is measured with magnetic resonance thermography (MRT) using temperature-dependent phase changes in proton resonance frequency. The ocular phantom contains a layer of melanosomes isolated from bovine retinal pigment epithelium. The phantom is heated by the 806-nm output of a continuous wave diode laser with an irradiance of 2.4 to 21.6 W/cm2 in a beam radius of 0.8 or 2.4 mm, depending on the experiment. MRT is performed with a 2 T magnet, and a two-turn, 6-cm-diam, circular radio frequency coil. Two-dimensional temperature gradients are measured within the plane of the melanin layer, as well as normal to it, with a temperature resolution of 1 degrees C or better. The temperature gradients extending within the melanin layer are broader than those orthogonal to the layer, consistent with the higher optical absorption and consequent heating in the melanin. The temperature gradients in the phantom measured by MRT closely approximate the predictions of a classical heat diffusion model. Three-dimensional temperature maps with a spatial resolution of 0.25 mm in all directions are also made. Although the temporal resolution is limited in the prototype system (22.9 s for a single image "slice"), improvements in future implementations are likely. These results indicate that MRT has sufficient spatial and temperature resolution to monitor target tissue temperature during transpupillary thermotherapy in the human eye.

Malformations and abnormalities of the petrous portion of the temporal bone; Fehlbildungen und Missbildungen des Felsenbeins

Energy Technology Data Exchange (ETDEWEB)

Reith, W.; Yilmaz, U. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany); Heumueller, I. [Westpfalzklinikum Kaiserslautern, Institut fuer Radiologie, Kaiserslautern (Germany)

2014-04-15

High-resolution computed tomography (HRCT) is the procedure of choice in the diagnostics of abnormalities of the middle and inner ear. It allows a detailed presentation of anatomical features and achieves the prerequisites for selection of the various therapeutic options. The highly diverse abnormalities can be described using detailed imaging analyses. Malformations with an abnormally developed modiolus are assumed to be early embryological defects, such as the classical Mondini dysplasia. The essential therapeutic option for middle ear deformities is still a cochlear implant. The domain of magnetic resonance imaging (MRI) is not only in the analysis of the cochlear nerve and for exclusion of fibrosis or ossification of the labyrinth but is also able to visualize details of isolated malformations, such as an extended vestibular aqueduct or subtle alterations to the vestibule or can visualize them better in comparison to CT. Radiological diagnostics are used not only for classification but also to recognize typical clinical problem situations and play a key role in the diagnostics of hearing disorders and selection of the optimal therapeutic procedure. (orig.) [German] Die hochaufloesende CT ist das Verfahren der Wahl in der Diagnostik von Fehlbildungen des Mittel- und Innenohrs. Sie erlaubt die detaillierte Darstellung anatomischer Details und schafft die Voraussetzung fuer die unterschiedlichen Therapieoptionen. Durch detaillierte bildgebenden Analysen koennen die unterschiedlichsten Fehlbildungen beschrieben werden. Fehlbildungen mit einem nicht normal ausgebildeten Modiolus werden als fruehere embryologische Schaedigungen als die klassische Mondini-Dysplasie angesehen. Die wesentliche therapeutische Option bei Mittelohrfehlbildung bleibt das Kochleaimplantat. Die Domaene der MRT liegt nicht nur in der Analyse des N. cochlearis und im Ausschluss von Fibrosierungen oder Ossifikationen des Labyrinths, sondern darueber hinaus ist sie in der Lage, Details einzelner

Diagnostic evaluatuin of gastrointestinal tumors; Diagnostik bei Tumoren im Gastrointestinaltrakt

Energy Technology Data Exchange (ETDEWEB)

Linke, R.; Tatsch, K. [Ludwig-Maximilians-Univ. Muenchen (Germany). Klinik und Poliklinik fuer Nuklearmedizin

1998-07-01

difficult to distinguish between chronic pancreatitis and pancreatic carcinoma. In such cases a PET scan may be helpful. For planning of surgery and for preoperative staging morphological imaging is essential, but in nearly 40% of the patients nonresectable tumors were detected intraoperatively, which were not diagnosed by preoperative CT or MRI. PET seems to be more accurate in this respect, too. (orig.) [Deutsch] Hauptaufgaben der radiologischen und nuklearmedizinischen Diagnostik bei gastrointestinalen Tumoren sind Diagnosesicherung sowie praeoperatives Staging. Die Hohlorgane des oberen und unteren GI-Traktes (Oesophagus, Magen, Duodenum, Kolon, Rektum) werden primaer endoskopisch und endosonographisch abgeklaert. CT oder MRT liefern Informationen ueber Ausdehnung des Tumors, eine Infiltration in umgebende Strukturen und das Vorliegen pathologischer Lymphknoten. Das sensitivste Verfahren zum Nachweis von Lymphknoten- oder Fernmetastasen ist die PET. Auch die Differenzierung eines Lokalrezidivs von postoperativer Narbenbildung, z.B. beim kolorektalen Karzinom, gelingt mit der PET fruehzeitiger als mit den konventionellen morphologischen Verfahren. Lebertumoren sollten primaer sonographisch und bei fraglicher Dignitaet anschliessend mittels MRT untersucht werden. In der Differentialdiagnostik von unklaren Leberherden ist die nuklearmedizinische Rezeptorszintigraphie wegweisend. Benigne Leberlaesionen koennen mit der Neogalaktoalbumin-(NGA-)Szintigraphie sicher von malignen Tumoren (Metastasen, hepatozellulaeres Karzinom [HCC]) abgegrenzt werden, da NGA-Rezeptoren nur auf funktionstuechtigen Hepatozyten experimentiert werden. Die Unterscheidung von Lebermetastasen und dem HCC gelingt mit der Insulinszintigraphie, da sich Insulin aufgrund einer Ueberexpression von Insulinrezeptoren mit HCC vermehrt anreichert. Ergeben die vorgeschalteten Untersuchungen den Verdacht auf einen malignen Prozess, sollte zusaetzlich eine CT-Arterioportographie durchgefuehrt werden, da dieses

Investigations on avoidance of hot cracks during laser welding of austenitic Cr-Ni steels and nickel-based alloys using temperature field tailoring. Final report; Untersuchungen zur Vermeidung von Heissrissen beim Laserstrahlschweissen von austenitischen Cr-Ni-Staehlen und Nickelbasislegierungen mittels Temperaturfeld-Tailoring. Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-08-08

. Zweitens wird bei rotationssymmetrischen Bauteilen, die mittels einer Axial-Rundnaht zu verschweissen sind, mit einem relativ einfachen Temperaturfeld, das durch Erwaermung des innen liegenden Fuegepartners vor und waehrend des Schweissens aufgebaut wird, ein Spannungsfeld erzeugt, das die Bildung von Heissrissen verhindert. Schliesslich konnte drittens ein heissrissfreies Laserstrahlschweissen des Stahls 1.4305 und der Nickelbasislegierung Udimet 720 bereits ohne den Einsatz zusaetzlicher Temperaturfelder erreicht werden. Die Grenzen der Einsetzbarkeit des Verfahrens bei Cr-Ni-Staehlen werden dann erreicht, wenn Quer-Heissrisse oder parallel zur Blechoberflaeche liegende Heissrisse entstehen. Die zur Vermeidung dieser Risse noetigen Druckspannungen in den Richtungen parallel zur Schweissnaht bzw. senkrecht zur Blechoberflaeche koennen mittels induktiver Erwaermung von der Blechoberseite aus nicht in der erforderlichen Groesse erzeugt werden. Ebenso stoesst das Verfahren an seine Grenzen, wenn Wiederaufschmelzungsrisse auftreten, was beim hier verwendeten Stahl 1.4435 der Fall war. Die Spannungen, die zur Verhinderung einer Rissoeffnung an den Korngrenzen der Waermeeinflusszone erforderlich waeren, konnten durch Temperaturfeld-Tailoring nicht erreicht werden. Die Moeglichkeit des heissrissfreien Schweissens des Stahls 1.4305 auch ohne Temperaturfeld-Tailoring ergibt sich hauptsaechlich aus dem primaer ferritischen Erstarrungsmodus des Stahls in der vorliegenden Legierungszusammensetzung. Ein industrieller Einsatz des Laserstrahlschweissens fuer diesen oft als nicht schweissbar klassifizierten Stahl erscheint moeglich, wenn bei der Legierungszusammensetzung auf niedrige Anteile der Austenitbildner Nickel, Kohlenstoff und Stickstoff Wert gelegt wird und damit eine stabil primaer ferritische Erstarrung erreicht wird. Fuer diesen Fall kommt es nicht zur Schwefelanreicherung an den Korngrenzen, wodurch die Bildung niedrigschmelzender Phasen und damit die Heissrissentstehung

Dynamic MRI of the liver with parallel acquisition technique. Characterization of focal liver lesions and analysis of the hepatic vasculature in a single MRI session

International Nuclear Information System (INIS)

Heilmaier, C.; Sutter, R.; Lutz, A.M.; Willmann, J.K.; Seifert, B.

2008-01-01

Purpose: to retrospectively evaluate the performance of breath-hold contrast-enhanced 3D dynamic parallel gradient echo MRI (pMRT) for the characterization of focal liver lesions (standard of reference: histology) and for the analysis of hepatic vasculature (standard of reference: contrast-enhanced 64-detector row computed tomography; MSCT) in a single MRI session. Materials and method: two blinded readers independently analyzed preoperative pMRT data sets (1.5T-MRT) of 45 patients (23 men, 22 women; 28 - 77 years, average age, 48 years) with a total of 68 focal liver lesions with regard to image quality of hepatic arteries, portal and hepatic veins, presence of variant anatomy of the hepatic vasculature, as well as presence of portal vein thrombosis and hemodynamically significant arterial stenosis. In addition, both readers were asked to identify and characterize focal liver lesions. Imaging parameters of pMRT were: TR/TE/matrix/slice thickness/acquisition time: 3.1 ms/1.4 ms/384 x 224/4 mm/15 - 17 s. MSCT was performed with a pitch of 1.2, an effective slice thickness of 1 mm and a matrix of 512 x 512. Results: based on histology, the 68 liver lesions were found to be 42 hepatocellular carcinomas (HCC), 20 metastases, 3 cholangiocellular carcinomas (CCC) as well as 1 dysplastic nodule, 1 focal nodular hyperplasia (FNH) and 1 atypical hemangioma. Overall, the diagnostic accuracy was high for both readers (91 - 100%) in the characterization of these focal liver lesions with an excellent interobserver agreement (κ-values of 0.89 [metastases], 0.97 [HCC] and 1 [CCC]). On average, the image quality of all vessels under consideration was rated good or excellent in 89% (reader 1) and 90% (reader 2). Anatomical variants of the hepatic arteries, hepatic veins and portal vein as well as thrombosis of the portal vein were reliably detected by pMRT. Significant arterial stenosis was found with a sensitivity between 86% and 100% and an excellent interobserver agreement (κ

Effect of fiber source on cell wall digestibility and rate of passage in rabbits.

Science.gov (United States)

García, J; Carabaño, R; de Blas, J C

1999-04-01

The influence of fiber source on fiber digestion and mean retention time was investigated. Six fibrous feedstuffs with wide differences in chemical composition and particle size were selected: paprika meal, olive leaves, alfalfa hay, soybean hulls, sodium hydroxide-treated barley straw, and sunflower hulls. Six diets were formulated to contain one of these ingredients as the sole source of fiber. To avoid nutrient imbalances, fiber sources were supplemented with different proportions of a concentrate free of fiber based on soy protein isolate, wheat flour, lard, and a vitamin and mineral mix to obtain diets containing at least 18.5% CP and 5% starch. Fecal apparent digestibility of nonstarch polysaccharides (NSPd) and its monomers, NDF, NDF-ADL, and ADF-ADL, were determined using four New Zealand White x California growing rabbits per diet. Total, ileorectal, and cecal mean retention times (tMRT, i-rMRT, and cMRT, respectively) were determined for diets based on paprika meal, olive leaves, soybean hulls, and sunflower hulls in 16 does (four per diet) fitted with T-cannulas at the terminal ileum. In both trials, DMI was negatively correlated with the proportion of fine particles (FP: 1.25 mm) (P lignification of NDF, considering lignin as the difference between ADL and acid detergent cutin, was only included as the third variable for the model of NDF digestibility. Digestibility of NSP was positively correlated with those of NDF, NDF-ADL, and ADF-ADL (r = .82, .87 and .85, respectively, P < .001); the latter was also highly correlated with the digestibility of the glucose included in the NSP fraction (r = .86; P < .001). Cecal mean retention time accounted for 63% of average tMRT, for most of the variability in tMRT (r = .99; P < .001), and was positively related to NSPd (r = .89; P < .001). From these results, we conclude that particle size is a major factor affecting fiber digestion efficiency, rate of passage, and feed intake in rabbits.

Long-term perspectives of technical and social development in Germany. Visions for research and technology policy; Langfristige Perspektiven technischer und gesellschaftlicher Entwicklung in Deutschland. Visionen fuer die Forschungs- und Technologiepolitik

Energy Technology Data Exchange (ETDEWEB)

Baron, W; Zweck, A

1995-12-01

This publication contains six contributions discussing the medium- and long-term perspectives of technical, social and economic development in Germany. (UA) [Deutsch] Die vorliegende Publikation enthaelt 6 Vortraege, die sich mit mittel- und langfristigen Perspektiven der technischen, sozialen und wirtschaftlichen Entwicklung in Deutschland befassen. (UA)

Virtual reality adaptive stimulation of limbic networks in the mental readiness training.

Science.gov (United States)

Cosić, Kresimir; Popović, Sinisa; Kostović, Ivica; Judas, Milos

2010-01-01

A significant proportion of severe psychological problems in recent large-scale peacekeeping operations underscores the importance of effective methods for strengthening the stress resilience. Virtual reality (VR) adaptive stimulation, based on the estimation of the participant's emotional state from physiological signals, may enhance the mental readiness training (MRT). Understanding neurobiological mechanisms by which the MRT based on VR adaptive stimulation can affect the resilience to stress is important for practical application in the stress resilience management. After the delivery of a traumatic audio-visual stimulus in the VR, the cascade of events occurs in the brain, which evokes various physiological manifestations. In addition to the "limbic" emotional and visceral brain circuitry, other large-scale sensory, cognitive, and memory brain networks participate with less known impact in this physiological response. The MRT based on VR adaptive stimulation may strengthen the stress resilience through targeted brain-body interactions. Integrated interdisciplinary efforts, which would integrate the brain imaging and the proposed approach, may contribute to clarifying the neurobiological foundation of the resilience to stress.

MRI of the temporomandibular joint. Technique, results, indications; Magnetresonanztomographie des Temporomandibulargelenkes: Untersuchungstechnik, Ergebnisse, Indikationsstellung

Energy Technology Data Exchange (ETDEWEB)

Vogl, T.J.; Abolmaali, N. [Frankfurt Univ. (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie

2001-11-01

An optimized examination protocol for the MRI evaluation of the temporomandibular joint (TMJ) is presented. The MRI protocol is based on an optimized coil technology, sequence design, and a programmed examination protocol for diagnostics of the TMJ. Depending on the clinical findings, MRI provides an all-in-one diagnostic protocol for the diagnosis of degenerative, inflammatory and tumorous lesions of the TMJ. MRI using an optimized examination protocol should become the primary examination protocol for diseases of the TMJ. (orig.) [German] Vorstellung der optimierten Untersuchungstechnik zur magnetresonanztomographischen (MRT) Evaluation des Temporomandibulargelenkes (TMG) und Darstellung der Ergebnisse und Indikationsstellung. Es werden die Spulentechnik, das Sequenzdesign, die Schichtorientierung und der programmierte Untersuchungsablauf in Abhaengigkeit von der klinischen Fragestellung praesentiert. In Abhaengigkeit von der klinischen Symptomatik stellt die MRT das primaere bildgebende Verfahren zur Diagnostik und Therapiekontrolle degenerativer, entzuendlicher und tumoroeser Prozesse des TMG dar. In Einzelfaellen muessen ergaenzend weitere radiologische Techniken wie die Orthopantomographie, die direkte Arthrographie und die Computertomographie zum Einsatz kommen. Die optimierte MRT des TMG erfordert eine dedizierte Untersuchungstechnik sowie spezielle Kenntnisse in der Beurteilung der akquirierten Bilder. (orig.)

Combining microwave resonance technology to multivariate data analysis as a novel PAT tool to improve process understanding in fluid bed granulation.

Science.gov (United States)

Lourenço, Vera; Herdling, Thorsten; Reich, Gabriele; Menezes, José C; Lochmann, Dirk

2011-08-01

A set of 192 fluid bed granulation batches at industrial scale were in-line monitored using microwave resonance technology (MRT) to determine moisture, temperature and density of the granules. Multivariate data analysis techniques such as multiway partial least squares (PLS), multiway principal component analysis (PCA) and multivariate batch control charts were applied onto collected batch data sets. The combination of all these techniques, along with off-line particle size measurements, led to significantly increased process understanding. A seasonality effect could be put into evidence that impacted further processing through its influence on the final granule size. Moreover, it was demonstrated by means of a PLS that a relation between the particle size and the MRT measurements can be quantitatively defined, highlighting a potential ability of the MRT sensor to predict information about the final granule size. This study has contributed to improve a fluid bed granulation process, and the process knowledge obtained shows that the product quality can be built in process design, following Quality by Design (QbD) and Process Analytical Technology (PAT) principles. Copyright © 2011. Published by Elsevier B.V.

Comparative analysis of the 1-mile run test evaluation formulae: assessment of aerobic capacity in male law enforcement officers aged 20-23 years.

Science.gov (United States)

Kayihan, Gürhan; Özkan, Ali; Köklü, Yusuf; Eyuboğlu, Ender; Akça, Firat; Koz, Mitat; Ersöz, Gülfem

2014-04-01

The purpose of this study was to compare values of aerobic performance in the 1-mile run test (1-MRT) using different formulae. Aerobic capacities of 351 male volunteers working for the Turkish National Police within the age range of 20-23 years were evaluated by the 1-MRT and the 20-metre shuttle run (20-MST). VO2max values were estimated by the prediction equations developed by George et al. (1993), Cureton et al. (1995) and Kline et al. (1987) for the 1-MRT and by Leger and Lambert (1982) for the 20-MST. The difference between the results of the different formulae was significant (p = 0.000). The correlation coefficient between the estimated VO2max using Cureton's equation, George's equation, Kline's equation and the 20-MST were 0.691 (p compares the use of 3 different formulae to estimate VO2max from 1-mile run/walk performance in male law enforcement officers aged 20-23 years for the first time and reports the most accurate formula to use when evaluating aerobic capacities of large numbers of healthy individuals.

The modified relaxation time function: A novel analysis technique for relaxation processes. Application to high-temperature molybdenum internal friction peaks

International Nuclear Information System (INIS)

Matteo, C.L.; Lambri, O.A.; Zelada-Lambri, G.I.; Sorichetti, P.A.; Garcia, J.A.

2008-01-01

The modified relaxation time (MRT) function, which is based on a general linear viscoelastic formalism, has several important mathematical properties that greatly simplify the analysis of relaxation processes. In this work, the MRT is applied to the study of the relaxation damping peaks in deformed molybdenum at high temperatures. The dependence of experimental data from these relaxation processes with temperature are adequately described by a Havriliak-Negami (HN) function, and the MRT makes it possible to find a relation between the parameters of the HN function and the activation energy of the process. The analysis reveals that for the relaxation peak appearing at temperatures below 900 K, the physical mechanism is related to a vacancy-diffusion-controlled movement of dislocations. In contrast, when the peak appears at temperatures higher than 900 K, the damping is controlled by a mechanism of diffusion in the low-temperature tail of the peak, and in the high-temperature tail of the peak the creation plus diffusion of vacancies at the dislocation line occurs

Sound radiation contrast in MR phase images. Method for the representation of elasticity, sound damping, and sound impedance changes

International Nuclear Information System (INIS)

Radicke, Marcus

2009-01-01

The method presented in this thesis combines ultrasound techniques with the magnetic-resonance tomography (MRT). An ultrasonic wave generates in absorbing media a static force in sound-propagation direction. The force leads at sound intensities of some W/cm 2 and a sound frequency in the lower MHz range to a tissue shift in the micrometer range. This tissue shift depends on the sound power, the sound frequency, the sound absorption, and the elastic properties of the tissue. A MRT sequence of the Siemens Healthcare AG was modified so that it measures (indirectly) the tissue shift, codes as grey values, and presents as 2D picture. By means of the grey values the sound-beam slope in the tissue can be visualized, and so additionally sound obstacles (changes of the sound impedance) can be detected. By the MRT images token up spatial changes of the tissue parameters sound absorption and elasticity can be detected. In this thesis measurements are presented, which show the feasibility and future chances of this method especially for the mammary-cancer diagnostics. [de

MRT fuel element inspection at Dounreay

Energy Technology Data Exchange (ETDEWEB)

Gibson, J.

1997-08-01

To ensure that their production and inspection processes are performed in an acceptable manner, ie. auditable and traceable, the MTR Fuel Element Fabrication Plant at Dounreay operates to a documented quality system. This quality system, together with the fuel element manufacturing and inspection operations, has been independently certified to ISO9002-1987, EN29002-1987 and BS5750:Pt2:1987 by Lloyd`s Register Quality Assurance Limited (LRQA). This certification also provides dual accreditation to the relevant German, Dutch and Australian certification bodies. This paper briefly describes the quality system, together with the various inspection stages involved in the manufacture of MTR fuel elements at Dounreay.

MRT des Pankreas: Radiologisch-pathologische Korrelation

NARCIS (Netherlands)

Helmberger, T.; Holzknecht, N.; Gauger, J.; Beuers, U.; Reiser, M.

1996-01-01

The typical MRI features of the most common pancreatic diseases, such as pancreatitis and adenocarcinoma of the pancreas, have been established. However, even in these common pancreatic disorders, MRI correlation with the underlying pathology is limited for clinical reasons. We emphasize

The evidence base for the use of internal dosimetry in the clinical practice of molecular radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Strigari, Lidia [Regina Elena National Cancer Institute, Laboratory of Medical Physics and Expert Systems, Rome (Italy); Konijnenberg, Mark [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands); Chiesa, Carlo [Instituto Nazionale Tumori, Department of Nuclear Medicine, Milan (Italy); Bardies, Manuel [UMR 1037 INSERM / Universite Paul Sabatier, Centre de Recherche en Cancerologie de Toulouse, Toulouse (France); Du, Yong [Royal Marsden NHS Foundation Trust, Department of Nuclear Medicine and PET/CT, Sutton, London (United Kingdom); Gleisner, Katarina Sjoegreen [Medical Radiation Physics, Clinical Sciences, Lund (Sweden); Lassmann, Michael [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Flux, Glenn [Royal Marsden NHS Foundation Trust and Institute of Cancer Research, Joint Department of Physics, Sutton (United Kingdom)

2014-10-15

Molecular radiotherapy (MRT) has demonstrated unique therapeutic advantages in the treatment of an increasing number of cancers. As with other treatment modalities, there is related toxicity to a number of organs at risk. Despite the large number of clinical trials over the past several decades, considerable uncertainties still remain regarding the optimization of this therapeutic approach and one of the vital issues to be answered is whether an absorbed radiation dose-response exists that could be used to guide personalized treatment. There are only limited and sporadic data investigating MRT dosimetry. The determination of dose-effect relationships for MRT has yet to be the explicit aim of a clinical trial. The aim of this article was to collate and discuss the available evidence for an absorbed radiation dose-effect relationships in MRT through a review of published data. Based on a PubMed search, 92 papers were found. Out of 79 studies investigating dosimetry, an absorbed dose-effect correlation was found in 48. The application of radiobiological modelling to clinical data is of increasing importance and the limited published data on absorbed dose-effect relationships based on these models are also reviewed. Based on National Cancer Institute guideline definition, the studies had a moderate or low rate of clinical relevance due to the limited number of studies investigating overall survival and absorbed dose. Nevertheless, the evidence strongly implies a correlation between the absorbed doses delivered and the response and toxicity, indicating that dosimetry-based personalized treatments would improve outcome and increase survival. (orig.)

Radiation resistivity of quartz core fiber, 3

International Nuclear Information System (INIS)

Gozen, Toshikazu; Suzuki, Toshiya; Hayashi, Tokuji; Tanaka, Hiroyuki; Okamoto, Shinichi.

1985-01-01

Radiation resistance characteristics were evaluated for a multi-mode quartz core fiber in low temperature region together with photobleaching effect depending on the incident light power and dependency on the wavelength of measuring rays. This report describes the results of the abovementioned items and the next step study of trial manufacturing of a pure-quartz single-mode fiber for the employment of longer wavelength rays and greater capacity in light transmission communication system. Quartz core fiber specimens were irradiated by 60 Co γ-ray source at -55 deg C to 80 deg C in a constant temperature bath and light transmission loss was determined under irradiation conditions. Low temperature characteristics were superior in an MRT (modified rod-in tube) pure quartz fiber prepared by the plasma method as compared to VAD quartz and Ge-GI fibers. The MRT fiber showed better quality than the Ge-GI fiber also in the photobleaching effect examination. As for the wavelength dependency, light transmission loss of the MRT fiber was less than that of the Ge-GI fiber. The MRT fiber also showed a superior quality in the wide range of irradiation temperatures. Based on the above-mentioned understandings, a pure-quartz single-mode fiber of both BF 3 -doped and F-doped cladding types were developed for longer wavelengths uses. The fibers could attain low light transmission loss of less than 1.0 dB/km at 1.30 μm of wavelength. At the standpoint of radiation resistivity, the BF 3 -doped fiber was found superior. (Takagi, S.)

Heterogeneity of Monosymptomatic Resting Tremor in a Prospective Study: Clinical Features, Electrophysiological Test, and Dopamine Transporter Positron Emission Tomography

Institute of Scientific and Technical Information of China (English)

Hua-Guang Zheng; Rong Zhang; Xin Li; Fang-Fei Li; Ya-Chen Wang; Xue-Mei Wang; Ling-Long Lu

2015-01-01

Background:The relationship between monosymptomatic resting tremor (mRT) and Parkinson's disease (PD) remains controversial.In this study,we aimed to assess the function ofpresynaptic dopaminergic neurons in patients with mRT by dopamine transporter positron emission tomography (DAT-PET) and to evaluate the utility of clinical features or electrophysiological studies in differential diagnosis.Methods:Thirty-three consecutive patients with mRT were enrolled prospectively.The Unified Parkinson's Disease Rating Scale and electromyography were tested before DAT-PET.Striatal asymmetry index (SAI) was calculated,and a normal DAT-PET was defined as a SAI of ＜15％.Scans without evidence of dopaminergic deficits (SWEDDs) were diagnosed in patients with a subsequent normal DAT-PET and structural magnetic resonance imaging.Results:Twenty-eight mRT patients with a significant reduction in uptake of DAT binding in the striatum were diagnosed with PD,while the remained 5 with a normal DAT-PET scan were SWEDDs.As for UPRDS,the dressing and hygiene score,walking in motor experiences of daily living (Part Ⅱ) and motor examination (Part Ⅲ) were significant different between two groups (P ＜ 0.05 andP＜ 0.01,respectively).Bilateral tremor was more frequent in the SWEDDs group (P ＜ 0.05).The frequency of resting tremor and the amplitude of postural tremor tend to be higher in the SWEDDs group (P =0.08 and P =0.05,respectively).Conclusions:mRT is heterogeneous in presynaptic nigrostriatal dopaminergic degeneration,which can be determined by DAT-PET brain imaging.Clinical and electrophysiological features may provide clues to distinguish PD from SWEDDs.

Influenza and other respiratory virus infections in outpatients with medically attended acute respiratory infection during the 2011-12 influenza season.

Science.gov (United States)

Zimmerman, Richard K; Rinaldo, Charles R; Nowalk, Mary Patricia; Gk, Balasubramani; Thompson, Mark G; Moehling, Krissy K; Bullotta, Arlene; Wisniewski, Stephen

2014-07-01

Respiratory tract infections are a major cause of outpatient visits, yet only a portion is tested to determine the etiologic organism. Multiplex reverse transcriptase polymerase chain reaction (MRT-PCR) assays for detection of multiple viruses are being used increasingly in clinical settings. During January-April 2012, outpatients with acute respiratory illness (≤ 7 days) were tested for influenza using singleplex RT-PCR (SRT-PCR). A subset was assayed for 18 viruses using MRT-PCR to compare detection of influenza and examine the distribution of viruses and characteristics of patients using multinomial logistic regression. Among 662 participants (6 months-82 years), detection of influenza was similar between the MRT-PCR and SRT-PCR (κ = 0.83). No virus was identified in 267 (40.3%) samples. Commonly detected viruses were human rhinovirus (HRV, 15.4%), coronavirus (CoV, 10.4%), respiratory syncytial virus (RSV, 8.4%), human metapneumovirus (hMPV, 8.3%), and influenza (6%). Co-detections were infrequent (6.9%) and most commonly occurred among those infections (P = 0.008), nasal congestion was more frequent in CoV, HRV, hMPV, influenza and RSV infections (P = 0.001), and body mass index was higher among those with influenza (P = 0.036). Using MRT-PCR, a viral etiology was found in three-fifths of patients with medically attended outpatient visits for acute respiratory illness during the influenza season; co-detected viruses were infrequent. Symptoms varied by viral etiology. © 2014 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Study of Hip Fracture Risk using Tree Structured Survival Analysis

Directory of Open Access Journals (Sweden)

Lu Y

2003-01-01

Full Text Available In dieser Studie wird das Hüftfraktur-Risiko bei postmenopausalen Frauen untersucht, indem die Frauen in verschiedene Subgruppen hinsichtlich dieses Risikos klassifiziert werden. Frauen in einer gemeinsamen Subgruppe haben ein ähnliches Risiko, hingegen in verschiedenen Subgruppen ein unterschiedliches Hüftfraktur-Risiko. Die Subgruppen wurden mittels der Tree Structured Survival Analysis (TSSA aus den Daten von 7.665 Frauen der SOF (Study of Osteoporosis Fracture ermittelt. Bei allen Studienteilnehmerinnen wurde die Knochenmineraldichte (BMD von Unterarm, Oberschenkelhals, Hüfte und Wirbelsäule gemessen. Die Zeit von der BMD-Messung bis zur Hüftfraktur wurde als Endpunkt notiert. Eine Stichprobe von 75% der Teilnehmerinnen wurde verwendet, um die prognostischen Subgruppen zu bilden (Trainings-Datensatz, während die anderen 25% als Bestätigung der Ergebnisse diente (Validierungs-Datensatz. Aufgrund des Trainings-Datensatzes konnten mittels TSSA 4 Subgruppen identifiziert werden, deren Hüftfraktur-Risiko bei einem Follow-up von im Mittel 6,5 Jahren bei 19%, 9%, 4% und 1% lag. Die Einteilung in die Subgruppen erfolgte aufgrund der Bewertung der BMD des Ward'schen Dreiecks sowie des Oberschenkelhalses und nach dem Alter. Diese Ergebnisse konnten mittels des Validierungs-Datensatzes reproduziert werden, was die Sinnhaftigkeit der Klassifizierungregeln in einem klinischen Setting bestätigte. Mittels TSSA war eine sinnvolle, aussagekräftige und reproduzierbare Identifikation von prognostischen Subgruppen, die auf dem Alter und den BMD-Werten beruhen, möglich. In this paper we studied the risk of hip fracture for post-menopausal women by classifying women into different subgroups based on their risk of hip fracture. The subgroups were generated such that all the women in a particular subgroup had relatively similar risk while women belonging to two different subgroups had rather different risks of hip fracture. We used the Tree Structured

Malignant rhabdoid tumor of the tongue: A rare occurrence.

Science.gov (United States)

Hazarika, Munlima; Rahman, Tashnin; Sarma, Anupam; Krishnatreya, Manigreeva

2014-05-01

Malignant rhabdoid tumors (MRTs) are highly aggressive neoplasms that most commonly occur in the kidneys of young children. Malignant rhabdoid tumor of the tongue is an extremely rare entity and very few have been reported in the literature. The course of extra-renal MRT is short and its prognosis is very poor. A 19-year-old female presented with a progressive swelling and restricted mobility of the tongue for over 3 months duration. We present here a locally advanced case of MRT of the tongue, its diagnosis, management and review of the literature related to it.

Update in breast MRT. Standards and quality management; Update in der Mamma-MRT-Technik. Untersuchungsstandards und Qualitaetssicherung

Energy Technology Data Exchange (ETDEWEB)

Kurtz, Claudia [Kantonsspital Luzern, Lucerne (Switzerland). Inst. fuer Radiologie

2013-06-15

Meanwhile breast MRI has emerged to an important tool for breast diagnostics, with a broad spectrum of technical requirements and interpretation guidelines. The use of breast MRI is reasonable and helpful, provided that an appropriate application and optimal technical conditions are fulfilled, otherwise unnecessary follow-up examinations or biopsies might be initiated. This article gives an overview about planning and performing the examination, describes the physical background for optimal acquisition protocols, gives support for post-processing and image interpretation and also refers to possible misinterpretations. (orig.)

Der Sinn der Lehre

DEFF Research Database (Denmark)

Beyes, Timon; Steyaert, Chris

2015-01-01

Anhand der Beschreibung und Reflexion einer universitären Lehrveranstaltung, die die Erkundung städtischer Affekte und Atmosphären mittels ethnographischer Praktiken zum Inhalt hat, umreißt unser Beitrag eine Pädagogik des Affekts und skizziert ihre Implikationen für den Sinnbegriff und das Theor...

[Deutschland, Russland und das Baltikum] / Bogus̮aw Dyba{250}

Index Scriptorium Estoniae

Dyba{250}, Bogus̮aw

2006-01-01

Rets. rmt.: Deutschland, Russland und das Baltikum. Beiträge zu einer Geschichte wechselvoller Beziehungen. Festschrift zum 85. Geburtstag von Peter Krupnikow, hrsg. v. Florian Anton und Leonid Luks (=Schriften des Zentralinstituts für Mittel- und Osteuropastudien. Bd.7), Böhlau Verlag, Köln-Weimar-Wien, 2005

Focal lesions in whole-body MRI in multiple myeloma. Quantification of tumor mass and correlation with disease-related parameters and prognosis; Fokale Laesionen in der Ganzkoerper-MRT beim multiplen Myelom. Quantifizierung der Tumorlast und Korrelation mit krankheitstypischen Parametern und Prognose

Energy Technology Data Exchange (ETDEWEB)

Brandelik, S.C.; Kauczor, H.U. [Universitaetsklinikum Heidelberg, Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Krzykalla, J.; Hielscher, T. [Deutsches Krebsforschungszentrum (dkfz), Biostatistik, Heidelberg (Germany); Hillengass, J. [Universitaetsklinikum Heidelberg, Haematologie und Onkologie, Heidelberg (Germany); Kloth, J.K. [Radiologie Loebau, Loebau (Germany); Weber, M.A. [Universitaetsklinikum Heidelberg, Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Universitaetsmedizin Rostock, Diagnostische und Interventionelle Radiologie, Rostock (Germany)

2018-01-15

In this study, we evaluated methods of quantification of tumor mass in whole-body MRI (wb-MRI) in multiple myeloma and correlated these with disease-related parameters in serum and bone marrow. We retrospectively evaluated wb-MRIs of 52 patients with focal infiltration pattern and a total of 700 focal lesions (subsequently called lesions). We determined the longest diameter (LD), the segmented volume (SV), and the morphology (spherical or non-spherical). We correlated total number/volume of the lesions with clinical parameters and prognosis and furthermore LD with SV. After that we analyzed the agreement of SV and estimated volume (EV) using the volume formula of a sphere based on LD. Results showed no significant correlations of total number/volume with prognosis or clinical parameters. The latter were situated predominantly in the normal range. Furthermore, 10% of lesions were spherical. SV and LD correlated significantly in single lesions and on patient level. SV was in lesions <6 cm{sup 3} systematically larger and in lesions ≥6 cm{sup 3} smaller than EV. In 95%, we found in small lesions a deviation of EV versus SV from +0.9 cm{sup 3} to -4.6 cm{sup 3} and in large lesions from +160 cm{sup 3} to -111 cm{sup 3} (EV-SV). Quantification of tumor mass in the focal infiltration pattern is performed more accurately by volumetry than LD due to the predominant existence of non-spherical lesions. The patient cohort with clinical parameters predominantly in the normal range is distributed to ISS stage I and partly pretreated, a fact that makes interpretation of absent correlations more difficult. Consider also a variation in activity of lesions and a diffuse infiltration not detectable by MRI. (orig.) [German] In dieser Studie wurden Methoden der Tumorlastquantifizierung in der Ganzkoerper-Magnetresonanztomographie (GK-MRT) beim Multiplen Myelom untersucht und mit krankheitstypischen Parametern in Serum und Knochenmark korreliert. Die GK-MRT von 52 Patienten mit

Active raster scanning with carbon ions. Reirradiation in patients with recurrent skull base chordomas and chondrosarcomas

Energy Technology Data Exchange (ETDEWEB)

Uhl, Matthias; Welzel, Thomas; Oelmann, Jan; Habl, Gregor; Hauswald, Henrik; Jensen, Alexandra; Debus, Juergen; Herfarth, Klaus [University of Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Ellerbrock, Malte [Heidelberg Ion Therapy Center (HIT), Heidelberg (Germany)

2014-07-15

To evaluate the safety and efficacy of reirradiation with carbon ions in patients with relapse of skull base chordoma and chondrosarcoma. Reirradiation with carbon ions was performed on 25 patients with locally recurrent skull base chordoma (n = 20) or chondrosarcoma (n = 5). The median time between the last radiation exposure and the reirradiation with carbon ions was 7 years. In the past, 23 patients had been irradiated once, two patients twice. Reirradiation was delivered using the active raster scanning method. The total median dose was 51.0 GyE carbon ions in a weekly regimen of five to six fractions of 3 GyE. Local progression-free survival (LPFS) was evaluated using the Kaplan-Meier method; toxicity was evaluated using the NCI Common Terminology Criteria for Adverse Events (CTCAE v.4.03). The treatment could be finished in all patients without interruption. In 80 % of patients, symptom control was achieved after therapy. The 2-year-LPFS probability was 79.3 %. A PTV volume of < 100 ml or a total dose of > 51 GyE was associated with a superior local control rate. The therapy was associated with low acute toxicity. One patient developed grade 2 mucositis during therapy. Furthermore, 12 % of patients had tympanic effusion with mild hypacusis (grade 2), while 20 % developed an asymptomatic temporal lobe reaction after treatment (grade 1). Only one patient showed a grade 3 osteoradionecrosis. Reirradiation with carbon ions is a safe and effective method in patients with relapsed chordoma and chondrosarcoma of the skull base. (orig.) [German] Evaluierung der Sicherheit und Wirksamkeit einer Re-Bestrahlung mittels Kohlenstoffionen bei Patienten mit Lokalrezidiv eines Chordoms und Chondrosarkoms der Schaedelbasis. Bei 25 Patienten mit einem Lokalrezidiv eines Chordoms (n = 20) oder Chondrosarkoms (n = 5) der Schaedelbasis erfolgte eine Re-Bestrahlung mittels Kohlenstoffionen. Die mediane Zeit zwischen letzter Bestrahlung und Re-Bestrahlung mit Kohlenstoffionen

Optimierung der Gesichtsklassifikation bei der Erkennung von Akromegalie

Directory of Open Access Journals (Sweden)

Frohner R

2013-01-01

Full Text Available In vorausgegangenen Studien konnte gezeigt werden, dass eine Gesichtsklassifikation mittels Gesichtsphotographien zur Diagnostik von Akromegalie mit guten Ergebnissen eingesetzt werden kann. In diesem Artikel werden die grundlegende Vorgehensweise der Klassifikation mittels der Software FIDA erläutert sowie Optimierungsansätze mit dem Ziel diskutiert, diese Methode näher an den klinischen Einsatz zu bringen. Die Gesichtsklassifikation basiert auf „Knotenpunkten“, die verteilt über die jeweilige Frontal- und/oder Seitenansicht des Gesichts platziert werden und den so genannten „Graphen“ bilden. Mittels mathematischer Verfahren erfolgt eine Analyse der zugrunde liegenden Textur des Bildes sowie die Auswertung geometrischer Informationen. Untersucht wird, wie sich die Reduktion von als irrelevant eingestuften Knoten auf das Klassifikationsergebnis auswirkt. Ebenso wird untersucht, wie sich neu definierte Knoten, die die typischen morphologischen Veränderungen der akromegalen Erkrankung im Gesicht berücksichtigen, auf die Klassifizierungsergebnisse auswirken. Die interne Validierung erfolgt an einem Datenset bestehend aus 57 an Akromegalie erkrankten Probanden (29 weiblich, 28 männlich sowie 59 Kontrollen (29 weiblich, 30 männlich. Die externe Validierung wird an einer weiteren Stichprobe gemessen, die zum Zeitpunkt der Präsentation auf der Tagung der European Neuroendocrine Association 2012 in Wien 13 akromegale Patienten (7 weiblich, 6 männlich sowie 45 Kontrollen (25 weiblich, 20 männlich umfasste. Die Datenbank wird ständig durch neue Probanden aus verschiedenen Quellen erweitert. Erste Ergebnisse zeigen, dass die Verwendung von Graphen mit reduzierten Knoten und von neuen Sets von Knoten unter Einbeziehung typischer morphologischer Veränderungen des Gesichts die Klassifizierung weiter verbessert. Diese Ergebnisse ermutigen zu weiteren Untersuchungen an einer erweiterten Datenbank.

Importance of diffusion imaging in liver metastases; Bedeutung der Diffusionsbildgebung bei Lebermetastasen

Energy Technology Data Exchange (ETDEWEB)

Riffel, P.; Schoenberg, S.O.; Krammer, J. [Medizinische Fakultaet Mannheim der Universitaet Heidelberg, Institut fuer Klinische Radiologie und Nuklearmedizin, Universitaetsmedizin Mannheim, Mannheim (Germany)

2017-05-15

Detection and characterization of focal liver lesions. Due to its excellent soft tissue contrast, the availability of liver-specific contrast agents and the possibility of functional imaging, magnetic resonance imaging (MRI) is the method of choice for the evaluation of focal liver lesions. Diffusion-weighted imaging (DWI) enables generation of functional information about the microstructure of a tissue besides morphological information. In the detection of focal liver lesions DWI shows a better detection rate compared to T2w sequences and a slightly poorer detection rate compared to dynamic T1w sequences. In principle, using DWI it is possible to distinguish malignant from benign liver lesions and also to detect a therapy response at an early stage. For both detection and characterization of focal liver lesions, DWI represents a promising alternative to the morphological sequences; however, a more detailed characterization with the use of further sequences should be carried out particularly for the characterization of solid benign lesions. For the assessment and prognosis of therapy response, DWI offers advantages compared to morphological sequences. For the detection of focal liver lesions DWI is in principle sufficient. After visual detection of a solid liver lesion a more detailed characterization should be carried out using further sequences (in particular dynamic T1w sequences). The DWI procedure should be used for the assessment and prognosis of a therapy response. (orig.) [German] Detektion und Charakterisierung fokaler Leberlaesionen. Die MRT ist aufgrund des exzellenten Weichteilkontrasts, der Verfuegbarkeit leberspezifischer Kontrastmittel und der Moeglichkeit funktioneller Bildgebung die Methode der Wahl zur Abklaerung fokaler Leberlaesionen. Die diffusionsgewichtete Bildgebung (''diffusion-weighted imaging'', DWI) ermoeglicht es, neben den rein morphologischen auch funktionelle Informationen ueber die Mikrostruktur eines Gewebes zu

Metal recovery via geobiotechnology; Metallgewinnung mittels Geobiotechnologie

Energy Technology Data Exchange (ETDEWEB)

Hedrich, Sabrina; Schippers, Axel [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Hannover (Germany). Fachbereich Geochemie der Rohstoffe

2017-02-15

Specialized acidophilic bacteria and archaea are able to extract valuable metals such as copper, gold, cobalt, nickel, zinc, and uranium from sulfide ores. This process is known as bioleaching and its application in the mining industry as biomining. Laboratory studies also demonstrated bioleaching of oxide ores such as laterites and of mining residues such as mine tailings as well as metal recycling from waste (secondary mining). Metals being leached have to be recovered from acidic polymetallic solutions (mine and process waters) which is possible via biosorption or biomineralisation.

Book review: Vetter, H. 2005. Terralog. Turtles of the World. Vol. 3. Central and South America

Directory of Open Access Journals (Sweden)

2006-12-01

Full Text Available Book review: Vetter, H. 2005. Terralog. Turtles of the World. Vol. 3. Central and South America/Schildkröten der Welt Band 3. Mittel- und Südamerika: 1-128, color pictures 606 + 9. Edition Chimaira, Frankfurt, Germany.ISBN 3-930612-82-8; 29.7 x 20.8 cm

Devil-nets of clues: True Detective and the search for meaning

DEFF Research Database (Denmark)

Tybjerg, Casper

2016-01-01

of the puzzle film genre as an interpretive framework, the existence of an audience interested in assuming the attitude of what Jason Mittell has called the forensic fan, and the choice of a traditional, one-episode-per-week release schedule. Finally, the article discusses the show’s ending and the disappointed...

Multidisciplinary rehabilitation treatment versus cognitive behavioural therapy for patients with chronic fatigue syndrome: a randomized controlled trial.

Science.gov (United States)

Vos-Vromans, D C W M; Smeets, R J E M; Huijnen, I P J; Köke, A J A; Hitters, W M G C; Rijnders, L J M; Pont, M; Winkens, B; Knottnerus, J A

2016-03-01

The aim of this trial was to evaluate the difference in treatment effect, at 26 and 52 weeks after the start of treatment, between cognitive behavioural therapy (CBT) and multidisciplinary rehabilitation treatment (MRT) for patients with chronic fatigue syndrome (CFS). Multicentre, randomized controlled trial of patients with CFS. Participants were randomly assigned to MRT or CBT. Four rehabilitation centres in the Netherlands. A total of 122 patients participated in the trial. Primary outcomes were fatigue measured by the fatigue subscale of the Checklist Individual Strength and health-related quality of life measured by the Short-Form 36. Outcomes were assessed prior to treatment and at 26 and 52 weeks after treatment initiation. A total of 114 participants completed the assessment at 26 weeks, and 112 completed the assessment at 52 weeks. MRT was significantly more effective than CBT in reducing fatigue at 52 weeks. The estimated difference in fatigue between the two treatments was -3.02 [95% confidence interval (CI) -8.07 to 2.03; P = 0.24] at 26 weeks and -5.69 (95% CI -10.62 to -0.76; P = 0.02) at 52 weeks. Patients showed an improvement in quality of life over time, but between-group differences were not significant. This study provides evidence that MRT is more effective in reducing long-term fatigue severity than CBT in patients with CFS. Although implementation in comparable populations can be recommended based on clinical effectiveness, it is advisable to analyse the cost-effectiveness and replicate these findings in another multicentre trial. © 2015 The Association for the Publication of the Journal of Internal Medicine.

Simulation of Cavity Flow by the Lattice Boltzmann Method using Multiple-Relaxation-Time scheme

International Nuclear Information System (INIS)

Ryu, Seung Yeob; Kang, Ha Nok; Seo, Jae Kwang; Yun, Ju Hyeon; Zee, Sung Quun

2006-01-01

Recently, the lattice Boltzmann method(LBM) has gained much attention for its ability to simulate fluid flows, and for its potential advantages over conventional CFD method. The key advantages of LBM are, (1) suitability for parallel computations, (2) absence of the need to solve the time-consuming Poisson equation for pressure, and (3) ease with multiphase flows, complex geometries and interfacial dynamics may be treated. The LBM using relaxation technique was introduced by Higuerea and Jimenez to overcome some drawbacks of lattice gas automata(LGA) such as large statistical noise, limited range of physical parameters, non- Galilean invariance, and implementation difficulty in three-dimensional problem. The simplest LBM is the lattice Bhatnager-Gross-Krook(LBGK) equation, which based on a single-relaxation-time(SRT) approximation. Due to its extreme simplicity, the lattice BGK(LBGK) equation has become the most popular lattice Boltzmann model in spite of its well-known deficiencies, for example, in simulating high-Reynolds numbers flow. The Multiple-Relaxation-Time(MRT) LBM was originally developed by D'Humieres. Lallemand and Luo suggests that the use of a Multiple-Relaxation-Time(MRT) models are much more stable than LBGK, because the different relaxation times can be individually tuned to achieve 'optimal' stability. A lid-driven cavity flow is selected as the test problem because it has geometrically singular points in the flow, but geometrically simple. Results are compared with those using SRT, MRT model in the LBGK method and previous simulation data using Navier-Stokes equations for the same flow conditions. In summary, LBM using MRT model introduces much less spatial oscillations near geometrical singular points, which is important for the successful simulation of higher Reynolds number flows

Simulations of Bingham plastic flows with the multiple-relaxation-time lattice Boltzmann model

Science.gov (United States)

Chen, SongGui; Sun, QiCheng; Jin, Feng; Liu, JianGuo

2014-03-01

Fresh cement mortar is a type of workable paste, which can be well approximated as a Bingham plastic and whose flow behavior is of major concern in engineering. In this paper, Papanastasiou's model for Bingham fluids is solved by using the multiplerelaxation-time lattice Boltzmann model (MRT-LB). Analysis of the stress growth exponent m in Bingham fluid flow simulations shows that Papanastasiou's model provides a good approximation of realistic Bingham plastics for values of m > 108. For lower values of m, Papanastasiou's model is valid for fluids between Bingham and Newtonian fluids. The MRT-LB model is validated by two benchmark problems: 2D steady Poiseuille flows and lid-driven cavity flows. Comparing the numerical results of the velocity distributions with corresponding analytical solutions shows that the MRT-LB model is appropriate for studying Bingham fluids while also providing better numerical stability. We further apply the MRT-LB model to simulate flow through a sudden expansion channel and the flow surrounding a round particle. Besides the rich flow structures obtained in this work, the dynamics fluid force on the round particle is calculated. Results show that both the Reynolds number Re and the Bingham number Bn affect the drag coefficients C D , and a drag coefficient with Re and Bn being taken into account is proposed. The relationship of Bn and the ratio of unyielded zone thickness to particle diameter is also analyzed. Finally, the Bingham fluid flowing around a set of randomly dispersed particles is simulated to obtain the apparent viscosity and velocity fields. These results help simulation of fresh concrete flowing in porous media.

Present and projected future mean radiant temperature for three European cities

Science.gov (United States)

Thorsson, Sofia; Rayner, David; Lindberg, Fredrik; Monteiro, Ana; Katzschner, Lutz; Lau, Kevin Ka-Lun; Campe, Sabrina; Katzschner, Antje; Konarska, Janina; Onomura, Shiho; Velho, Sara; Holmer, Björn

2017-09-01

Present-day and projected future changes in mean radiant temperature, T mrt in one northern, one mid-, and one southern European city (represented by Gothenburg, Frankfurt, and Porto), are presented, and the concept of hot spots is adopted. Air temperature, T a , increased in all cities by 2100, but changes in solar radiation due to changes in cloudiness counterbalanced or exacerbated the effects on T mrt. The number of days with high T mrt in Gothenburg was relatively unchanged at the end of the century (+1 day), whereas it more than doubled in Frankfurt and tripled in Porto. The use of street trees to reduce daytime radiant heat load was analyzed using hot spots to identify where trees could be most beneficial. Hot spots, although varying in intensity and frequency, were generally confined to near sunlit southeast-southwest facing walls, in northeast corner of courtyards, and in open spaces in all three cities. By adding trees in these spaces, the radiant heat load can be reduced, especially in spaces with no or few trees. A set of design principles for reducing the radiant heat load is outlined based on these findings and existing literature.

Tarsaltunnel syndrome - MRI diagnosis; Tarsaltunnelsyndrom. MR-Diagnostik

Energy Technology Data Exchange (ETDEWEB)

Trattnig, S. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria). Abt. fuer Osteoradiologie; Breitenseher, M. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria). Abt. fuer Osteoradiologie; Haller, J. [Radiologische Abt., Hanuschkrankenhaus, Wien (Austria)]|[Ludwig Boltzmann-Institut fuer Osteologie, Wien (Austria); Helbich, T. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria). Abt. fuer Osteoradiologie; Gaebler, C. [Universitaetsklinik fuer Unfallchirurgie, Wien (Austria); Imhof, H. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria). Abt. fuer Osteoradiologie

1995-07-01

Clinical findings and symptoms of tarsal tunnel are commonly vague and diffuse and electrodiagnostic studies do not provide definitive diagnosis. MR imaging with its excellent soft tissue contrast can demonstrate clearly the anatomy of the tarsal tunnel and its contents. MRI is able to demonstrate a space-occypyinglesion and its relationship to the posterior tibial nerve and its branches. This information aids in surgical planning by determining the extent of the decompression required. MR imaging may also be used to follow up non-surgical causes of tarsal tunnel syndrome such as tenosynovitis. (orig.) [Deutsch] Klinische Befunde und Symptomoe des Tarsaltunnelsyndroms sind haeufig diffus, und elektrodiagnostische Untersuchungen liefern keine definitive Diagnose. Die MRT mit ihrem exzellenten Weichteilkontrast erlaubt eine ausgezeichnete Darstellung der Anatomie des Tarsaltunnels und seines Inhaltes. Die MRT ermoeglicht auch die Darstellung von raumfordernden Laesionen und ihre Beziehung zum N.tibialis posterior bzw. seiner Aeste. Diese Information hilft in der chirurigschen Planung, in dem das Ausmass der notwendigen Dekompression bestimmt werden kann. Die MRT ist auch geeignet als nichtinvasive Verlaufskontrolle von Ursachen eines Tarsaltunnelsyndroms, die keinen chirugischen Eingriff erfordern wie z.B. einer Tenosynovitis. (orig.)

Effects of Vitrectomy on Recurrent Macular Edema due to Branch Retinal Vein Occlusion after Intravitreal Injection of Bevacizumab

Directory of Open Access Journals (Sweden)

Tatsuya Yunoki

2013-01-01

Full Text Available Purpose. To evaluate the effects of pars plana vitrectomy (PPV on recurrent macular edema due to branch retinal vein occlusion (BRVO after intravitreal injections of bevacizumab (IVB. Methods. This retrospective study included 22 eyes of 22 patients who underwent single or multiple IVB injections for macular edema due to BRVO and showed a recurrence of macular edema. All patients then underwent PPV and were followed up for more than 6 months after the surgery with examinations of best corrected visual acuity (BCVA and optical coherence tomography (OCT. OCT parameters were central macular thickness (CMT and average retinal thickness in a 1-mm-diameter circular region at the fovea (MRT. Results. Mean BCVA, CRT, and MRT were significantly improved from the baseline after PPV. Greater improvement of BCVA, CRT, and MRT was obtained after 1 month of IVB than after 6 months of PPV. No eyes showed worsening of macular edema after the surgery. Conclusion. PPV improved BCVA and recurrent macular edema due to BRVO, but PPV that was less effective than IVB had been in the same patients. PPV may be one of the treatment options for recurrent macular edema due to BRVO after IVB.

Enhancing Understanding of Magnetized High Energy Density Plasmas from Solid Liner Implosions Using Fluid Modeling with Kinetic Closures

Science.gov (United States)

Masti, Robert; Srinivasan, Bhuvana; King, Jacob; Stoltz, Peter; Hansen, David; Held, Eric

2017-10-01

Recent results from experiments and simulations of magnetically driven pulsed power liners have explored the role of early-time electrothermal instability in the evolution of the MRT (magneto-Rayleigh-Taylor) instability. Understanding the development of these instabilities can lead to potential stabilization mechanisms; thereby providing a significant role in the success of fusion concepts such as MagLIF (Magnetized Liner Inertial Fusion). For MagLIF the MRT instability is the most detrimental instability toward achieving fusion energy production. Experiments of high-energy density plasmas from wire-array implosions have shown the requirement for more advanced physics modeling than that of ideal magnetohydrodynamics. The overall focus of this project is on using a multi-fluid extended-MHD model with kinetic closures for thermal conductivity, resistivity, and viscosity. The extended-MHD model has been updated to include the SESAME equation-of-state tables and numerical benchmarks with this implementation will be presented. Simulations of MRT growth and evolution for MagLIF-relevant parameters will be presented using this extended-MHD model with the SESAME equation-of-state tables. This work is supported by the Department of Energy Office of Science under Grant Number DE-SC0016515.

Parking Space Occupancy at Rail Stations in Klang Valley

Directory of Open Access Journals (Sweden)

Ho Phooi Wai

2017-01-01

Full Text Available The development of Klang Valley Integrated Rapid Transit system in Klang Valley, Malaysia has been quickly gaining momentum during the recent years. There will be two new MRT lines (MRT Line 1 and MRT Line 2 and one new LRT line (LRT Line 3 extended from the current integrated rail transit system by year 2020 with more than 90 new rail stations. With the substantial addition of potential rail passengers, there are doubts whether the existing Park and Ride facilities in Klang Valley are able to accommodate the future parking space demand at rail stations. This research studies the parking occupancy at various Park and Ride facilities in Klang Valley namely Taman Jaya, Asia Jaya, Taman Paramount, Taman Bahagia and Kelana Jaya by applying the non-conventional method utilizing Google Earth imageries. Results showed that the parking occupancy rate at these LRT stations were 100% or more before the commencement of LRT extension (Kelana Jaya and Ampang Lines in 2016 and in the range of 36% to 100% after the commencement of LRT extension due to the additionally built car parks and changes in parking pattern with dispersed passenger traffic.

Radiological imaging in early diagnosis of rheumatoid arthritis. The role of ultrasound and magnetic resonance imaging; Radiologische Fruehdiagnostik der rheumatoiden Arthritis. Stellenwert von Ultraschall und Magnetresonanztomographie

Energy Technology Data Exchange (ETDEWEB)

Platzgummer, H.; Schueller-Weidekamm, C. [AKH, Medizinische Universitaet Wien, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria)

2012-02-15

For optimal therapy management of patients with rheumatoid arthritis (RA) specific and sensitive diagnostic methods are essential for assessment of disease activity. In addition to projection radiography, imaging techniques, in particular magnetic resonance imaging (MRI) and ultrasound (US) are becoming increasingly more important for the early diagnosis of RA. The MRI and US techniques play a key role in the early imaging diagnostics of RA. Measurement of inflammation activity represents the basis of therapeutic decision-making and can be quantitatively and qualitatively determined with MRI and US. Synovitis and bone marrow edema are predictors of erosion. (orig.) [German] Fuer das optimale Therapiemanagement bei Patienten mit rheumatoider Arthritis (RA) sind spezifische und sensible diagnostische Methoden zur Beurteilung der Krankheitsaktivitaet unerlaesslich. Neben der Projektionsradiographie gewinnen die bildgebenden Methoden zur Fruehdiagnostik der RA, insbesondere die Magnetresonanztomographie (MRT) und der Ultraschall (US), zunehmend an Bedeutung. MRT und US spielen eine Schluesselrolle in der bildgebenden Fruehdiagnostik der RA. Die Messung der Entzuendungsaktivitaet stellt die Basis fuer die Therapieentscheidung dar. Sie kann mit dem US und der MRT quantitativ und semiquantitativ bestimmt werden. Synovialitis und Knochenmarkoedem sind Praediktoren fuer Erosionen. (orig.)

But you should be the specialist! Weak Mental Rotation Performance in Aviation Security Screeners.Reduced performance level in aviation security with no gender effect.

Directory of Open Access Journals (Sweden)

Jenny Kathinka Krüger

2016-03-01

Full Text Available Aviation security screeners analyze a large number of X-ray images per day and seem to be experts in mentally rotating diverse kinds of visual objects. A robust gender-effect that men outperform women in the Vandenberg & Kuse mental rotation task has been well documented over the last years. In addition it has been shown that training can positively influence the overall task-performance. Considering this, the aim of the present study was to investigate whether security screeners show better performance in the Mental Rotation Test (MRT independently of gender. Forty-seven security screeners of both sexes from two German airports were examined with a computer based MRT. Their performance was compared to a large sample of control subjects. The well-known gender-effect favoring men on mental rotation was significant within the control group. However, the security screeners did not show any sex differences suggesting an effect of training and professional performance. Surprisingly this specialized group showed a lower level of overall MRT performance than the control participants. Possible aviation related influences such as secondary effects of work-shift or expertise which can cumulatively cause this result are discussed.

You Should Be the Specialist! Weak Mental Rotation Performance in Aviation Security Screeners - Reduced Performance Level in Aviation Security with No Gender Effect.

Science.gov (United States)

Krüger, Jenny K; Suchan, Boris

2016-01-01

Aviation security screeners analyze a large number of X-ray images per day and seem to be experts in mentally rotating diverse kinds of visual objects. A robust gender-effect that men outperform women in the Vandenberg & Kuse mental rotation task has been well documented over the last years. In addition it has been shown that training can positively influence the overall task-performance. Considering this, the aim of the present study was to investigate whether security screeners show better performance in the Mental Rotation Test (MRT) independently of gender. Forty-seven security screeners of both sexes from two German airports were examined with a computer based MRT. Their performance was compared to a large sample of control subjects. The well-known gender-effect favoring men on mental rotation was significant within the control group. However, the security screeners did not show any sex differences suggesting an effect of training and professional performance. Surprisingly this specialized group showed a lower level of overall MRT performance than the control participants. Possible aviation related influences such as secondary effects of work-shift or expertise which can cumulatively cause this result are discussed.

Effect of variation in active route timeout and my route timeout on the performance of AODV-ETX protocol in mobile adhoc network

Science.gov (United States)

Purnomo, A.; Widyawan; Najib, W.; Hartono, R.; Hartatik

2018-03-01

Mobile adhoc network (MANET) consists of nodes that are independent. A node can communicate each other without the presence of network infrastructure. A node can act as a transmitter and receiver as well as a router. This research has been variation in active route timeout and my route timeout on the performance of AODV-ETX protocol in MANET. The AODV-ETX protocol is the AODV protocol that uses the ETX metric. Performance testing is done on the static node topology with 5 m x 5 m node grid model where the distance between nodes is 100 m and node topology that consists of 25 nodes moves randomly with a moving speed of 1.38 m/s in an area of 1500 m x 300 m. From the test result, on the static node, AODV protocol-ETX shows optimal performance at a value MRT and ART of 10 s and 15 s, but showed a stable performance in the value of MRT and ART ≥60 s, while in randomly moved node topology shows stable performance in the value of MRT and ART ≥80 s.

Rhabdomyolysis in DOMS

Energy Technology Data Exchange (ETDEWEB)

Martinez Carsi, C. [Hospital 9 d' Octubre, Valencia (Spain). Serveis de Medicina Nuclear; Ruiz Hernandez, G. [Hospital Clinic Universitari, Valencia (Spain). Serveis de Medicina Nuclear; Sanchez Marchori, C.; Munoz Moliner, J. [Hospital 9 d' Octubre, Valencia (Spain). Serveis de Traumatologia

1999-07-01

A 26-year-old man with a previous history of external twin bursitis was remitted to our Department for a bone scintigraphy. Before the study, the patient performed an elevated number of intense sprints. Bone scintigraphy showed a bilaterally increased activity in both anterior rectum muscles suggesting rhabdomyolysis. Biochemical studies and MRT confirmed the diagnosis. (orig.) [German] Ein 26jaehriger Mann mit vorausgehender M.-gastrocnemius-Bursitis wurde zur Skelettszintigraphie in unsere Abteilung ueberwiesen. Vor der Untersuchung fuehrte der Patient mehrere Kurzstreckensprints durch. Die Skelettszintigraphie ergab eine erhoehte Aktivitaet in beiden Mm. recti femoris, die auf eine Rhabdomyolyse hinweist. Biochemische Untersuchungen und MRT bestaetigten die Diagnose. (orig.)

calvyn oor die leiding van die heilige gees in die verklaring van die

African Journals Online (AJOL)

Mittel alters, bis er zur Ruhe kommt bei den kanonischen Schriften der. Urzeit der christlichen Ära (Barth ... (ego tamen dimoveri non possum ab amore compendii, CO 10, 403). Deur die boodskap van die .... Idem ergo spiritus qui per os prophetarum loquutus est, in corda nostra penetret necesse est, ut persuadeat fideliter ...

Environmental monitoring of mercury in waters. Reagent-free and rapid determination of mercury at trace levels.; Umweltmonitoring von Quecksilber in Gewaessern. Reagenzienfreie und schnelle Bestimmung von Hg im Spurenbereich

Energy Technology Data Exchange (ETDEWEB)

Huber, Jessica; Leopold, Kerstin [Ulm Univ. (Germany). Inst. fuer Analytische und Bioanalytische Chemie

2013-05-15

With the help of nano gold collectors for the enrichment of the total mercury content of water samples can be analyzed fully automatically using atomic fluorescence spectrometry without extensive sample preparation. [German] Mit Hilfe von Nanogoldkollektoren zur Anreicherung kann der Gesamtquecksilber-Gehalt von Gewaesserproben vollautomatisiert mittels Atomfluoreszenzspektrometrie ohne aufwendige Probenvorbereitung analysiert werden.

Modernisierungsbemühungen in islamischen Gesellschaften

Directory of Open Access Journals (Sweden)

Regina Harzer

2006-07-01

Full Text Available Im Tagungsband sind Beiträge über heterogene Lebensformen von Frauen aus islamischen Kulturkreisen versammelt. Das gemeinsame Anliegen der Autorinnen ist das Bemühen um gegenseitiges Verständnis im internationalen Diskurs. Sie konkretisieren dieses Bemühen mittels kritischer und selbstkritischer Betrachtung islamischer Verhältnisse.

Spontaneous osteonecrosis of the knee joint: MR imaging before and after administration of gadopentetate-dimeglumine, comparison to CT, scintigraphy, and histology; Spontane Osteonekrose des Kniegelenkes: MRT im Vergleich zur CT, Szintigraphie und Histologie

Energy Technology Data Exchange (ETDEWEB)

Lang, P. [Dept. of Radiology, Univ. of California, San Francisco, CA (United States); Grampp, S. [Dept. of Radiology, Univ. of California, San Francisco, CA (United States); Vahlensieck, M. [Dept. of Radiology, Univ. of California, San Francisco, CA (United States)]|[Radiologische Klinik, Bonn Univ. (Germany); Mauz, M. [Dept. of Radiology, Univ. of California, San Francisco, CA (United States)]|[Radiologische Klinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Steiner, E. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria); Schwickert, H. [Dept. of Radiology, Univ. of California, San Francisco, CA (United States)]|[Radiologische Klinik, Universitaetsklinik Mainz (Germany); Gindele, A. [Dept. of Radiology, Univ. of California, San Francisco, CA (United States); Felix, R. [Radiologische Klinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Genant, H.K. [Dept. of Radiology, Univ. of California, San Francisco, CA (United States)

1995-06-01

Eight patients with spontaneous osteonecrosis of the knee joint underwent MR imaging before and after i.v. administration of Gd-DTPA. Nuclear scintigraphy was performed in all 8 patients, three patients also had CT scans of the knee area. Histologic correlation was available in three patients. Increased radionuclide uptake was observed in all patients. In one patient, however, scintigraphy showed increased radionuclide uptake consistent with ostenecrosis only in the medial femoral condyle, while MR imaging demonstrated osteonecrosis both in the medial as well as the lateral femoral condyles. MR demonstrated areas of low signal intensity on precontrast T{sub 1}-weighted images in the femoral condyle in all patients. All these areas showed high signal intensity on T{sub 2}-weighted images. On postcontrast T{sub 1}-weighted images, signal intensity increase was either homogeneous throughout the lesion or it was seen at the periphery of the lesion in a band-like pattern. Histologically, the areas of high signal intensity on T{sub 2}-weighted and on postcontrast T{sub 1}-weighted images corresponded to granulation tissue. (orig./MG) [Deutsch] Wir untersuchten acht Patienten mit einer spontanen Osteonekrose des Kniegelenkes mit der MRT. Ein Vergleich zum szintigraphischen Befund wurde bei allen 8 Patienten und zur CT bei drei Patienten angestellt. Eine histologische Korrelation war bei drei Patienten moeglich. Bei allen 8 Patienten zeigten die T{sub 1}-gewichteten MR-Tomographien Zonen mit reduzierter Signalintensitaet in den Kondylen, waehrend die Laesionen in den T{sub 2}-gewichteten Aufnahmen eine hoehere Signalintensitaet als das normale Knochenmark hatten. Nach Gabe von Gd-DTPA war entweder eine homogene Signalerhoehung oder eine bandfoermige Signalintensitaetszunahme in der Peripherie der Laesion zu sehen. Die Zonen mit hoher Signalintensitaet in der T{sub 2}-gewichteten Aufnahme oder mit Kontrastmittelanreicherung entsprachen histologisch Granulationsgewebe an der

Leadership pipeline i den offentlige sektor

DEFF Research Database (Denmark)

Dahl, Kristian Aagaard; Molly-Søholm, Thorkil

en rejse ind i hjertet af offentlig ledelse med fokus på lederniveauerne: topchef, funktionel chef, leder af ledere og leder af medarbejdere. Med afsæt i righoldige eksempler og fortællinger fra virkeligheden introduceres læseren for ledelsesteorien den Offentlige Leadership Pipeline, som giver...... enkelte lederniveauer og udvikle ledertalenter. Teorien byder på et detaljeret ledelsesgrundlag, hvorudfra den offentlige organisation kan bygge en professionel værdikæde for ledelse ved at forme lederprofiler, -rekruttering, -uddannelse, -evaluering m.m. Leadership Pipeline i den offentlige sektor er...... baseret på et treårigt dansk praksisorienteret forskningsprojekt med deltagelse af 15 offentlige organisationer, som repræsenterer kommunerne, regionerne og staten. Projektet har videreudviklet en af de sidste 10 års mest indflydelsesrige ledelseteorier i de største private organisationer, Leadership...

Genetische Veränderungen an primären Prostatakarzinom-Biopsien in Korrelation zum klinischen Verlauf

Directory of Open Access Journals (Sweden)

Steiner T

2002-01-01

Full Text Available Die der Entstehung des Prostatakarzinoms zugrundeliegenden bzw. mit einem Progreß vergesellschafteten genetischen Veränderungen sind noch weitgehend unbekannt. Ziel der vorliegenden retrospektiven Untersuchung war die Erfassung genetischer Aberrationen an paraffineigebettetem Material primärer Prostatakarzinom-Biopsien und die Korrelation der Daten zum klinischen Verlauf. In 28 karzinomtragenden primären Prostatabiopsien wurden die Tumorareale gekennzeichnet. Nach Dissektion der Tumorzellen wurden die Proben mittels "comparative genomic hybridization" (CGH analysiert. Daten zum klinischen Verlauf der Patienten wurden erfaßt. Die mittlere Nachbeobachtungszeit betrug 36 Monate, alle Patienten wurden hormonablativ behandelt. 11 Patienten (39 % wiesen unter laufender Therapie einen Tumorprogreß auf. In 25 (88 % der 28 untersuchten Tumorareale konnten genetische Aberrationen detektiert werden, im Mittel fanden wir 4,8 Aberrationen je Tumor. Das Verhältnis Verlust / Zugewinn betrug 1,3 / 1. Folgende chromosomale Veränderungen wurden häufig festgestellt: Verluste von 6q in 40 %; von 8p in 32 %; von 16q in 21 %; von 18q in 21 %; Zugewinne von 8q in 32 %; von 17 in 43 %. In Korrelation zum klinischen Verlauf fand sich ein Zugewinn von 8q signifikant häufiger bei Patienten, welche im Beobachtungszeitraum einen Tumorprogreß entwickelten (64 % vs. 12 %; p = 0,0001. In der primären Tumorbiopsie waren bei progredienten Patienten im Mittel 5,3, bei Patienten ohne Tumorprogreß 3,8 Aberrationen je Tumor nachzuweisen. Unsere Ergebnisse zeigen, daß Veränderungen der Chromosomen 6q, 8, 16q, 17 und 18q regelmäßig beim Prostatakarzinom auftreten. Karzinome mit klinisch ungünstigem Verlauf weisen bereits in der primären Biopsie eine hohe genetische Instabilität auf.

Einfluss des Internets auf das Informations-, Einkaufs- und Verkehrsverhalten

Science.gov (United States)

Nerlich, Mark R.; Schiffner, Felix; Vogt, Walter

Mit Daten aus eigenen Erhebungen können das einkaufsbezogene Informations- und Einkaufsverhalten im Zusammenhang mit den verkehrlichen Aspekten (Distanzen, Verkehrsmittel, Wegekopplungen) dargestellt werden. Die Differenzierung in die drei Produktkategorien des täglichen, mittelfristigen und des langfristigen Bedarfs berücksichtigt in erster Linie die Wertigkeit eines Gutes, die seine Erwerbshäufigkeit unmittelbar bestimmt. Der Einsatz moderner IKT wie das Internet eröffnet dem Endverbraucher neue Möglichkeiten bei Information und Einkauf. Die verkehrliche Relevanz von Online-Shopping wird deutlich, wenn man berücksichtigt, dass im Mittel rund 17% aller Online-Einkäufe, die die Probanden durchgeführt haben, Einkäufe in Ladengeschäften ersetzen. Dies gilt in verstärktem Maße für Online-Informationen: etwa die Hälfte hätte alternativ im stationären Einzelhandel stattgefunden. Da der Erwerb von Gütern des täglichen Bedarfs häufig nahräumlich und in relevantem Anteil nicht-motorisiert erfolgen kann, sind in diesem Segment - im Gegensatz zum mittel- und langfristigen Bedarf - nur geringe Substitutionseffekte zu beobachten.

Comparative study of the discrete velocity and lattice Boltzmann methods for rarefied gas flows through irregular channels.

Science.gov (United States)

Su, Wei; Lindsay, Scott; Liu, Haihu; Wu, Lei

2017-08-01

Rooted from the gas kinetics, the lattice Boltzmann method (LBM) is a powerful tool in modeling hydrodynamics. In the past decade, it has been extended to simulate rarefied gas flows beyond the Navier-Stokes level, either by using the high-order Gauss-Hermite quadrature, or by introducing the relaxation time that is a function of the gas-wall distance. While the former method, with a limited number of discrete velocities (e.g., D2Q36), is accurate up to the early transition flow regime, the latter method (especially the multiple relaxation time (MRT) LBM), with the same discrete velocities as those used in simulating hydrodynamics (i.e., D2Q9), is accurate up to the free-molecular flow regime in the planar Poiseuille flow. This is quite astonishing in the sense that less discrete velocities are more accurate. In this paper, by solving the Bhatnagar-Gross-Krook kinetic equation accurately via the discrete velocity method, we find that the high-order Gauss-Hermite quadrature cannot describe the large variation in the velocity distribution function when the rarefaction effect is strong, but the MRT-LBM can capture the flow velocity well because it is equivalent to solving the Navier-Stokes equations with an effective shear viscosity. Since the MRT-LBM has only been validated in simple channel flows, and for complex geometries it is difficult to find the effective viscosity, it is necessary to assess its performance for the simulation of rarefied gas flows. Our numerical simulations based on the accurate discrete velocity method suggest that the accuracy of the MRT-LBM is reduced significantly in the simulation of rarefied gas flows through the rough surface and porous media. Our simulation results could serve as benchmarking cases for future development of the LBM for modeling and simulation of rarefied gas flows in complex geometries.

3 tesla magnetic resonance imaging in children and adults with congenital heart disease; 3-Tesla-Magnetresonanztomographie zur Untersuchung von Kindern und Erwachsenen mit angeborenen Herzfehlern

Energy Technology Data Exchange (ETDEWEB)

Voges, I.; Hart, C.; Kramer, H.H.; Rickers, C. [Universitaetsklinikum Schleswig-Holstein, Klinik fuer angeborene Herzfehler und Kinderkardiologie, Kiel (Germany); Jerosch-Herold, M. [Harvard Medical School, Department of Radiology, Brigham and Women' s Hospital, Boston (United States); Helle, M. [Universitaetsklinikum Schleswig-Holstein, Institut fuer Neuroradiologie, Kiel (Germany)

2010-09-15

Cardiovascular magnetic resonance imaging (CMR) has become a routinely used imaging modality for congenital heart disease. A CMR examination allows the assessment of thoracic anatomy, global and regional cardiac function, blood flow in the great vessels and myocardial viability and perfusion. In the clinical routine cardiovascular MRI is mostly performed at field strengths of 1.5 Tesla (T). Recently, magnetic resonance systems operating at a field strengths of 3 T became clinically available and can also be used for cardiovascular MRI. The main advantage of CMR at 3 T is the gain in the signal-to-noise ratio resulting in improved image quality and/or allowing higher acquisition speed. Several further differences compared to MRI systems with lower field strengths have to be considered for practical applications. This article describes the impact of CMR at 3 T in patients with congenital heart disease by meanings of methodical considerations and case studies. (orig.) [German] Die kardiovaskulaere Magnetresonanztomographie (MRT) hat sich zu einer etablierten bildgebenden Methode zur Untersuchung von Patienten mit angeborenen Herzfehlern entwickelt. Sie erlaubt in einer einzigen Untersuchung die exakte Beurteilung von Anatomie, globaler und regionaler Funktion, Blutfluessen sowie der myokardialen Perfusion und Vitalitaet. In der klinischen Routine erfolgen die Untersuchungen zumeist bei einer Feldstaerke von 1,5 Tesla (T), mittlerweile gibt es jedoch Geraete und Bildgebungstechniken, die die kardiovaskulaere MRT auch bei 3 T ermoeglichen. Der wesentliche Vorteil der MRT bei 3 T ist das hoehere Signal-zu-Rausch-Verhaeltnis, das sowohl zu einer Verbesserung der Bildqualitaet als auch zu einer Verkuerzung der Untersuchungszeit genutzt werden kann. Darueber hinaus bestehen verschiedene andere Unterschiede gegenueber Systemen mit niedriger Feldstaerke, die im praktischen Einsatz beachtet werden muessen. Dieser Artikel beschreibt die Erfahrungen der 3-T-MRT fuer die

Effect of the dietary level of cull pinto beans (Phaseolus vulgaris on ruminal fermentation, kinetics, and digestibility of hair lambs

Directory of Open Access Journals (Sweden)

Francisco Castillo Rangel

Full Text Available ABSTRACT The objective was to evaluate the effect of three levels of cull pinto beans (CPB; Phaseolus vulgaris on ruminal fermentation, kinetics, and nutrient digestibility in hair lambs. Six cannulated lambs averaging 56.6±3.8 kg were used and were randomly assigned to one of three treatments. Treatments were: 0.0 kg kg−1 of CPB in the supplement (control; 0.25 kg kg−1 of CPB in the supplement (CB25; and 0.40 kg kg−1 of CPB in the supplement (CB40. Dry matter intake, ruminal pH, NH3, and volatile fatty acid (VFA concentration, methane production, Kp (passage rate, MRT (mean retention time, and digestibility of dry matter, crude protein, and neutral detergent fiber were evaluated. Data were analyzed in a Latin square design, repeated in line, by MIXED procedure of SAS. Estimates used for Kp and MRT were obtained by a non-linear regression model (PROC NLIN. Dry matter intake was reduced by supplementation of CPB. No differences were found in ruminal pH or ruminal NH3. During the trial, differences were found for ruminal VFA concentration (mM, which were greater for the CB25 group. The propionate:acetate ratio was greater for the CB40 treatment. Methane production (mM/m differed among treatments, but it was the greatest for the CB40 group. Passage rate (kg kg−1/h and MRT (h were similar among treatments and the digestibility (kg kg−1 of dry matter, crude protein, and neutral detergent fiber was not different among treatments. The inclusion of 0.25 kg kg−1 of CPB in the diet of hair lambs allows for appropriate nutrient digestion without affecting Kp and MRT and increases the molar proportion of the ability of VFA to maintain acetate:propionate ratio without increasing methane production.

Digesta retention patterns of solute and different-sized particles in camelids compared with ruminants and other foregut fermenters.

Science.gov (United States)

Dittmann, Marie T; Runge, Ullrich; Ortmann, Sylvia; Lang, Richard A; Moser, Dario; Galeffi, Cordula; Schwarm, Angela; Kreuzer, Michael; Clauss, Marcus

2015-07-01

The mean retention times (MRT) of solute or particles in the gastrointestinal tract and the forestomach (FS) are crucial determinants of digestive physiology in herbivores. Besides ruminants, camelids are the only herbivores that have evolved rumination as an obligatory physiological process consisting of repeated mastication of large food particles, which requires a particle sorting mechanism in the FS. Differences between camelids and ruminants have hardly been investigated so far. In this study we measured MRTs of solute and differently sized particles (2, 10, and 20 mm) and the ratio of large-to-small particle MRT, i.e. the selectivity factors (SF(10/2mm), SF(20/2mm), SF(20/10mm)), in three camelid species: alpacas (Vicugna pacos), llamas (Llama glama), and Bactrian camels (Camelus bactrianus). The camelid data were compared with literature data from ruminants and non-ruminant foregut fermenters (NRFF). Camelids and ruminants both had higher SF(10/2mm)FS than NRFF, suggesting convergence in the function of the FS sorting mechanism in contrast to NRFF, in which such a sorting mechanism is absent. The SF(20/10mm)FS did not differ between ruminants and camelids, indicating that there is a particle size threshold of about 1 cm in both suborders above which particle retention is not increased. Camelids did not differ from ruminants in MRT(2mm)FS, MRTsoluteFS, and the ratio MRT(2mm)FS/MRTsoluteFS, but they were more similar to 'cattle-' than to 'moose-type' ruminants. Camelids had higher SF(10/2mm)FS and higher SF(20/2mm)FS than ruminants, indicating a potentially slower particle sorting in camelids than in ruminants, with larger particles being retained longer in relation to small particles.

Modeling, measuring, and mitigating instability growth in liner implosions on Z

Science.gov (United States)

Peterson, Kyle

2015-11-01

Electro-thermal instabilities result from non-uniform heating due to temperature dependence in the conductivity of a material. In this talk, we will discuss the role of electro-thermal instabilities on the dynamics of magnetically accelerated implosion systems. We present simulations that show electro-thermal instabilities form immediately after the surface material of a conductor melts and can act as a significant seed to subsequent magneto-Rayleigh-Taylor (MRT) instability growth. We discuss measurement results from experiments performed on Sandia National Laboratories Z accelerator to investigate signatures of electro-thermal instability growth on well-characterized initially solid aluminum or beryllium rods driven with a 20 MA, 100 ns risetime current pulse. These measurements show good agreement with electro-thermal instability simulations and exhibit larger instability growth than can be explained by MRT theory alone. Recent experiments have confirmed simulation predictions of dramatically reduced instability growth in solid metallic rods when thick dielectric coatings are used to mitigate density perturbations arising from the electro-thermal instability. These results provide further evidence that the inherent surface roughness of the target is not the dominant seed for the MRT instability, in contrast with most inertial confinement fusion approaches. These results suggest a new technique for substantially reducing the integral MRT growth in magnetically driven implosions. Indeed, recent results on the Z facility with 100 km/s Al and Be liner implosions show substantially reduced growth. These new results include axially magnetized, CH-coated beryllium liner radiographs in which the inner liner surface is observed to be remarkably straight and uniform at a radius of about 120 microns (convergence ratio ~20). Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under

THE INFLUENCE OF BALL VELOCITY AND COURT ILLUMINATION ON REACTION TIME FOR TENNIS VOLLEY

Directory of Open Access Journals (Sweden)

Jui-hung Tu

2010-03-01

Full Text Available The he purpose of this study is to examine the effects of ball velocity, court illumination, and volley type on the reaction time (RT of a tennis athlete for a volley stroke. Eights cases with two different ball velocities (high and low, two volley types (forehand and backhand and two court illumination levels (dark and bright were studied. The 30 participating subjects consisted of 18 male and 12 female college tennis athletes (age: 24 ± 3.2 yr, with a United States Tennis Association (USTA ranking above 2.5. In order to ensure the validity of real-world correlations, the experiments were designed to simulate real competition situations. Reaction times were measured for volley strokes in response to different approaching ball velocities (high: 25.05 ± 0.37 m/s and low: 17.56 ± 0.92 m·s-1 for several volley types (forehand and backhand and court illumination levels (55649 ± 4292 lux and 363.24 ± 6.53 lux on the court. During the tests, the signals from an electromyogram sensor and a 3-axis accelerometer (± 50 g were recorded using an NI DAQ card (NI PXI-6251 and then analyzed to determine reaction time (RT, premotor reaction time (PRT, and motor reaction time (MRT through the LabVIEW system. Subsequent 3-way ANOVA analysis indicated no RT, PRT, or MRT interaction between ball velocity, volley type and illumination. The ball velocity and illumination parameters did affect RT and PRT values significantly with p < 0.05, no significant variation in MRT was observed across any implemented experimental conditions. All experimental results indicate that ball velocity and illumination levels strongly affect the value of PRT, but have no significant effect on the value of MRT, the changes in RT were dominated by PRT

Comparative study of the discrete velocity and lattice Boltzmann methods for rarefied gas flows through irregular channels

Science.gov (United States)

Su, Wei; Lindsay, Scott; Liu, Haihu; Wu, Lei

2017-08-01

Rooted from the gas kinetics, the lattice Boltzmann method (LBM) is a powerful tool in modeling hydrodynamics. In the past decade, it has been extended to simulate rarefied gas flows beyond the Navier-Stokes level, either by using the high-order Gauss-Hermite quadrature, or by introducing the relaxation time that is a function of the gas-wall distance. While the former method, with a limited number of discrete velocities (e.g., D2Q36), is accurate up to the early transition flow regime, the latter method (especially the multiple relaxation time (MRT) LBM), with the same discrete velocities as those used in simulating hydrodynamics (i.e., D2Q9), is accurate up to the free-molecular flow regime in the planar Poiseuille flow. This is quite astonishing in the sense that less discrete velocities are more accurate. In this paper, by solving the Bhatnagar-Gross-Krook kinetic equation accurately via the discrete velocity method, we find that the high-order Gauss-Hermite quadrature cannot describe the large variation in the velocity distribution function when the rarefaction effect is strong, but the MRT-LBM can capture the flow velocity well because it is equivalent to solving the Navier-Stokes equations with an effective shear viscosity. Since the MRT-LBM has only been validated in simple channel flows, and for complex geometries it is difficult to find the effective viscosity, it is necessary to assess its performance for the simulation of rarefied gas flows. Our numerical simulations based on the accurate discrete velocity method suggest that the accuracy of the MRT-LBM is reduced significantly in the simulation of rarefied gas flows through the rough surface and porous media. Our simulation results could serve as benchmarking cases for future development of the LBM for modeling and simulation of rarefied gas flows in complex geometries.

Detecting the impact of bank and channel modification on invertebrate communities in Mediterranean temporary streams (Sardinia, SW Italy).

Science.gov (United States)

Buffagni, Andrea; Tenchini, Roberta; Cazzola, Marcello; Erba, Stefania; Balestrini, Raffaella; Belfiore, Carlo; Pagnotta, Romano

2016-09-15

We hypothesized that reach-scale, bank and channel modification would impact benthic communities in temporary rivers of Sardinia, when pollution and water abstraction are not relevant. A range of variables were considered, which include both artificial structures/alterations and natural features observed in a stream reach. Multivariate regression trees (MRT) were used to assess the effects of the explanatory variables on invertebrate assemblages and five groups, characterized by different habitat modification and/or features, were recognized. Four node variables determined the splits in the MRT analysis: channel reinforcement, tree-related bank and channel habitats, channel modification and bank modification. Continuity of trees in the river corridor diverged among MRT groups and significant differences among groups include presence of alders, extent of channel shading and substrate diversity. Also, the percentage of in-stream organic substrates, in particular CPOM/Xylal, showed highly significant differences among groups. For practical applications, thresholds for the extent of channel reinforcement (40%) and modification (10%) and for bank alteration (≈30%) were provided, that can be used to guide the implementation of restoration measures. In moderately altered river reaches, a significant extent of tree-related habitats (≈5%) can noticeably mitigate the effects of morphological alteration on aquatic invertebrates. The outcomes highlight the importance of riparian zone management as an opportune, achievable prospect in the restoration of Mediterranean temporary streams. The impact of bank and channel modification on ecological status (sensu WFD) was investigated and the tested benthic metrics, especially those based on abundance data, showed legible differences among MRT groups. Finally, bank and channel modification appears to be a potential threat for the conservation of a few Sardo-Corsican endemic species. The introduction of management criteria that

Benchmarking and validation of a Geant4-SHADOW Monte Carlo simulation for dose calculations in microbeam radiation therapy.

Science.gov (United States)

Cornelius, Iwan; Guatelli, Susanna; Fournier, Pauline; Crosbie, Jeffrey C; Sanchez Del Rio, Manuel; Bräuer-Krisch, Elke; Rosenfeld, Anatoly; Lerch, Michael

2014-05-01

Microbeam radiation therapy (MRT) is a synchrotron-based radiotherapy modality that uses high-intensity beams of spatially fractionated radiation to treat tumours. The rapid evolution of MRT towards clinical trials demands accurate treatment planning systems (TPS), as well as independent tools for the verification of TPS calculated dose distributions in order to ensure patient safety and treatment efficacy. Monte Carlo computer simulation represents the most accurate method of dose calculation in patient geometries and is best suited for the purpose of TPS verification. A Monte Carlo model of the ID17 biomedical beamline at the European Synchrotron Radiation Facility has been developed, including recent modifications, using the Geant4 Monte Carlo toolkit interfaced with the SHADOW X-ray optics and ray-tracing libraries. The code was benchmarked by simulating dose profiles in water-equivalent phantoms subject to irradiation by broad-beam (without spatial fractionation) and microbeam (with spatial fractionation) fields, and comparing against those calculated with a previous model of the beamline developed using the PENELOPE code. Validation against additional experimental dose profiles in water-equivalent phantoms subject to broad-beam irradiation was also performed. Good agreement between codes was observed, with the exception of out-of-field doses and toward the field edge for larger field sizes. Microbeam results showed good agreement between both codes and experimental results within uncertainties. Results of the experimental validation showed agreement for different beamline configurations. The asymmetry in the out-of-field dose profiles due to polarization effects was also investigated, yielding important information for the treatment planning process in MRT. This work represents an important step in the development of a Monte Carlo-based independent verification tool for treatment planning in MRT.

Frequency and doses of diagnostic and interventional X-ray applications. Trends between 2007 and 2014; Haeufigkeit und Dosis diagnostischer und interventioneller Roentgenanwendungen. Trends zwischen 2007 und 2014

Energy Technology Data Exchange (ETDEWEB)

Nekolla, E.A. [BfS - Bundesamt fuer Strahlenschutz, Abteilung Medizinischer und Beruflicher Strahlenschutz, Neuherberg (Germany); Schegerer, A.A.; Griebel, J.; Brix, G.

2017-07-15

der Patienten in diesem Anwendungsbereich eine hohe Bedeutung zukommt. Auswertung und Bewertung aktueller Daten zu Haeufigkeit und Dosis von Roentgenanwendungen sowie von zeitlichen Entwicklungen fuer die Jahre 2007 bis 2014. Die Haeufigkeit von Roentgenanwendungen wurde fuer den ambulanten Bereich ueber Gebuehrenziffern der erbrachten radiologischen Leistungen abgeschaetzt, fuer den stationaeren Bereich mithilfe von Krankenhausstatistiken. Repraesentative Werte fuer die effektive Dosis pro Roentgenanwendung wurden fuer die betrachteten Jahre ueberwiegend aus Daten der Aerztlichen Stellen ermittelt. Im Jahr 2014 wurden in Deutschland etwa 140 Mio. Roentgenanwendungen durchgefuehrt, hiervon etwa 40 % im zahnmedizinischen Bereich. Im Mittel erfolgten 2007-2014 nahezu konstant 1,7 Anwendungen pro Einwohner und Jahr. Neben der zahnmedizinischen Diagnostik wurden am haeufigsten konventionelle Untersuchungen des Skeletts und des Thorax durchgefuehrt. Die CT-Haeufigkeit nahm um ca. 40 % zu. Mit etwa 55 % war der Anstieg bei der MRT zwar noch deutlicher, jedoch wurden insgesamt noch immer mehr CT- als MRT-Untersuchungen durchgefuehrt. Die Dosiswerte pro Untersuchung nahmen trotz der in den letzten Jahren etablierten Methoden zur Dosisreduktion nur leicht ab. In der Konsequenz nahm die mittlere effektive Dosis pro Einwohner im Untersuchungszeitraum von knapp 1,4 auf 1,6 mSv zu - im Wesentlichen aufgrund der zunehmenden CT-Haeufigkeit. Die Prinzipien der Rechtfertigung und Optimierung von medizinischen Strahlenanwendungen sind - insbesondere bei CT-Untersuchungen - in jedem Einzelfall konsequent anzuwenden. (orig.)

THE INVESTIGATION OF BRUCELLA ANTIBODY WITH MILK RING TEST AND AGGLUTINATION TEST IN MILK COLLECTED FROM SAMSUN REGION

Directory of Open Access Journals (Sweden)

Goknur TERZI

2006-06-01

Full Text Available In this study Brucella antibodies were investigated with agglutination test (Whey-AT and Milk Ring Test (MRT in a total of 100 milk samples as 50 of cow milk and 50 of goat milk collected from center and villages of Samsun. According to MRT Brucella antibodies was positive at 10 samples (20 % of cow milk and 6 samples (12 % of goat milk. In cow milk, 4 (8 % positive, 3 (6 % suspicious and 43 (86 % negative samples; in goat milk 3 (6 % positive, 2 (4 % suspicious and 45 (90 % negative samples were determined according to antibodies titre of serum agglutination test (Whey-AT. [TAF Prev Med Bull 2006; 5(3.000: 196-203

Use of stereographic projection for worldwide numerical weather prediction with a regional nested model

Energy Technology Data Exchange (ETDEWEB)

Prenosil, T. [Amt fuer Wehrgeophysik, Traben-Trarbach (Germany)

1998-01-01

Mittels einer fiktiven Polrotation ist das Deutsche Amt fuer Wehrgeophysik in der Lage, auf der Basis eines regelmaessigen Netzmodells fuer eine stereographische Ebene fuer jeden beliebigen Punkt der Erde hochaufloesende Wettervorhersagen zu erstellen. Die horizontale Koordinatentransformation garantiert numerische Stabilitaet fuer grosse Zeitschritte zu vertretbaren Kosten. Die Modellergebnisse werden mit Hilfe des Visualisierungsprogramms Vis5D vorgestellt. (orig.)

Entwicklung einer Produktstrategie für einen Veranstaltungskalender Wirtschaftswissenschaften

OpenAIRE

Steinhagen, Elisabeth

2014-01-01

Diese Arbeit hat das Ziel, am Beispiel des ZBW-Veranstaltungskalenders zu zeigen, dass eine Produktstrategie ein wertvolles Instrument ist, um ein Informationsprodukt erfolgreich zu etablieren bzw. weiterzuentwickeln. Dafür werden in Anlehnung an Methoden der strategischen Unternehmensplanung und des Produktmanagements wichtige Einflussfaktoren für das Produkt ZBWVeranstaltungskalender systematisch identifiziert und mittels IST-Analyse, Zielgruppenanalyse sowie Wettbewerbsanalyse unters...

Value of different MR techniques in diagnosis of degenerative disorders of the hyaline cartilage - in vitro study on 50 joint specimens of the knee with 1.5 T; Vergleich von verschiedenen MRT-Techniken in der Diagnose von degenerativen Knorpelerkrankungen - in-vitro-Studie an 50 Gelenkpraeparaten des Knies bei 1,5 T

Energy Technology Data Exchange (ETDEWEB)

Bachmann, G. [Klinikum der Univ. Giessen (Germany). Abt. Diagnostische Radiologie; Heinrichs, C. [Klinikum der Univ. Giessen (Germany). Inst. fuer Pathologie; Juergensen, I. [Klinikum der Univ. Giessen (Germany). Orthopaedische Klinik; Rominger, M. [Klinikum der Univ. Giessen (Germany). Abt. Diagnostische Radiologie; Scheiter, A. [Klinikum der Univ. Giessen (Germany). Abt. Diagnostische Radiologie; Rau, W.S. [Klinikum der Univ. Giessen (Germany). Abt. Diagnostische Radiologie

1997-05-01

Purpose: An experimental study was performed on joint specimens of the knee to assess the advantages and disadvantages of 14 generally available sequences in cartilage imaging. Methods: Each of the 50 surgically exposed cadaveric joints of the knee was examined by the following sequences: T{sub 1}, proton- and T{sub 2} weighted spin echo(SE) sequences, proton- and T{sub 2} weighted Turbo-SE, T{sub 1} weighted SE with fat suppression, MTC combined with T{sub 1}-weighted SE and T{sub 2} weighted FLASH-2 D, STIR, FISP-3 D, FLASH-3 D (with fat suppression), and MR arthrography. We assessed the image quality by a scale, signal to noise-ratio of cartilage and joint fluid, and the accuracy in detection of cartilage lesions. Pathology and arthroscopy were reference methods to MRI, and demonstrated grade 1-4 lesions on 186 of 300 joint facettes. Results: Advanced stages of cartilage lesions (65 grade 3 and 4 lesions) were detected by standard SE sequences in 67-94%. Application of volume techniques (FISP-3 D, FLASH-3 D), high definition matrix (512 pixel), MTC with FLASH-2 D and MR-arthrography improved the sensitivity up to 82-100%. Superficial lesions (65 grade 2 lesions) were demonstrated in 3-38%, and on MR arthrography in 45%. Structural changes (56 Grade 1 lesions) were recorded on MRI in only 10%. Conclusions: With regard to standard SE sequences, the detectability of cartilage lesions can be improved by techniques that use 512 matrices, selective cartilage imaging, and volume acquisition. (orig.) [Deutsch] Ziel: In einer experimentellen Studie an Gelenkpraeparaten des Knies wurden die Vor- und Nachteile von 14 allgemein verfuegbaren MRT-Sequenzen in der Knorpeldiagnostik dargestellt. Methode: 50 chirurgisch exstirpierte Kniegelenkpraeparate wurden nacheinander mit folgenden Techniken untersucht: Klassische Spin-Echo(SE)-Sequenz in T{sub 1}-, Protonen- und T{sub 2}-Wichtung, Turbo-SE in Protonen- und T{sub 2}-Wichtung, Fettsuppression mit T{sub 1}-gew. SE, MTC in

Speech Intelligibility in Noise Using Throat and Acoustic Microphones

National Research Council Canada - National Science Library

Acker-Mills, Barbara

2004-01-01

... speech intelligibility. Speech intelligibility for signals generated by an acoustic microphone, a throat microphone, and the two microphones together was assessed using the Modified Rhyme Test (MRT...

Assessing intraindividual variability in sustained attention: reliability, relation to speed and accuracy, and practice effects

Directory of Open Access Journals (Sweden)

HAGEN C. FLEHMIG

2007-06-01

Full Text Available We investigated the psychometric properties of competing measures of sustained attention. 179 subjects were assessed twice within seven day's time with a test designed to measure sustained attention, or concentration, respectively. In addition to traditional performance indices [i.e., speed (MRT and accuracy (E%], we evaluated two intraindividual response time (RT variability measures: standard deviation (SDRT and coefficient of variation (CVRT. For the overall test, both indices were reliable. SDRT showed good to acceptable retest reliability for all subtests. For CVRT, retest reliability coefficients ranged from very good to not satisfactory. While the reversed-word recognition test proved highly reliable, the mental calculation test and the arrows test were not sufficiently reliable. CVRT was only slightly correlated but SDRT was highly correlated with MRT. In contrast to substantial practice gains for MRT, SDRT and E%, only CVRT proved to be stable. In conclusion, CVRT appears to be a potential index for assessing performance variability: it is reliable for the overall test, only moderately correlated with speed, and virtually not affected by practice. However, before applying CVRT in practical assessment settings, additional research is required to elucidate the impact of task-specific factors on the reliability of this performance measure.

Mitochondrial Replacement Techniques, Scientific Tourism, and the Global Politics of Science.

Science.gov (United States)

Chan, Sarah; Palacios-González, César; De Jesús Medina Arellano, María

2017-09-01

The United Kingdom is the first and so far only country to pass explicit legislation allowing for the licensed use of the new reproductive technology known as mitochondrial replacement therapy. The techniques used in this technology may prevent the transmission of mitochondrial DNA diseases, but they are controversial because they involve the manipulation of oocytes or embryos and the transfer of genetic material. Some commentators have even suggested that MRT constitutes germline genome modification. All eyes were on the United Kingdom as the most likely location for the first MRT birth, so it was a shock when, on September 27, 2016, an announcement went out that the first baby to result from use of the intervention had already been born. In New York City, United States-based scientist John Zhang used maternal spindle transfer (one of the recognized MRT methods) to generate five embryos for a woman carrying oocytes with deleterious mutations of the mitochondrial DNA. Zhang then shipped the only euploid embryo to Mexico, where it was transferred to the mother's uterus. Zhang's team's travel across international borders to carry out experimental procedures represents a form of scientific tourism that has not been properly ethically explored; it can, however, have seriously detrimental effects for developing countries. © 2017 The Hastings Center.