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Sample records for diffusionsgewichteten mrt uebersicht

  1. 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

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    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

  2. Central pontine myelinolysis with a hyperintense lesion in diffusion weighted MRI: overview by means of a case report; Zentrale pontine Myelinolyse mit hyperintenser Laesion im diffusionsgewichteten MRT: Uebersicht anhand eines Fallberichtes

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    Kuhn, J.; Bewermeyer, H. [Neurologische Klinik, Kliniken der Stadt Koeln gGmbH, Krankenhaus Merheim, Koeln (Germany); Harzheim, A. [Radiologische Klinik, Kliniken der Stadt Koeln gGmbH, Krankenhaus Merheim, Koeln (Germany)

    2005-07-01

    Central pontine myelinolysis (CPM) is a demyelinating disease of the pons often associated with demyelination of other areas of the central nervous system (CNS). The etiology and pathogenesis of this disorder are still not fully understood. However, almost all cases of CPM are related to severe diseases or chronic alcoholism and occur in the setting of rapidly corrected serum hyponatremia and hypotonicity respectively. Depending on the involvement of other CNS structures, the clinical picture can vary considerably. Magnetic resonance imaging is the most sensitive investigation for the antemortem diagnosis of CPM, although the radiological findings lag behind and do not necessarily correlate with the clinical picture. Quite obviously diffusion-weighted imaging can be useful in the rapid diagnosis of CPM. This short review summarizes the current knowledge on the pathogenesis, clinical presentation, radiological findings, prognosis and therapeutic approaches of CPM. Characteristical clinical features and MR-findings including hyperintensity on diffusion-weighted images are illustrated by a typical case. (orig.)

  3. Clinical dictionary of MRT

    International Nuclear Information System (INIS)

    Herborn, C.U.; Zink, C.

    2007-01-01

    MRT is the method of choice in many clinical problems. It is also one of the most complex imaging procedures, requiring much technical and physical knowledge and also detailed knowledge of the signal response of physiological and pathological tissues in the many variants of contrast enhancement, image reconstruction and image processing. In 2006, the pocket dictionary of MRT was published by the same publisher. It met with much positive response, which induced the publication of this new dictionary. With more than 3000 terms and definitions elaborated in cooperation with an excellent practician, the clinical applications of MRT are illustrated by typical findings and examples. (orig.)

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

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    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

  5. MRT in non-palbable testes; MRT bei nichttastbaren Hoden

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    Ivanov, A. [Humboldt-Univ., Berlin (Germany). Medizinische Fakultaet (Charite), Inst. fuer Roentgendiagnostik; Dewey, C. [Humboldt-Univ., Berlin (Germany). Medizinische Fakultaet (Charite), Inst. fuer Roentgendiagnostik; Fahlenkamp, D. [Humboldt-Univ., Berlin (Germany). Medizinische Fakultaet (Charite), Klinik und Poliklinik fuer Urologie; Luening, M. [Humboldt-Univ., Berlin (Germany). Medizinische Fakultaet (Charite), Inst. fuer Roentgendiagnostik

    1994-03-01

    Magnetic resonance imaging was performed in 22 male patients for localisation of 27 nonpalpable undescended testes. The operative verification, carried out in 19 testes (15 patients) served as basis for checking on the accuracy of MRI results and for their comparison with those of sonography and laparoscopy. The impalpable testis was localised via MRI in 13 cases and its lack was correctly established in three cases. There were three false MRI diagnoses. The suspicion of two intraabdominal localised testes were not confirmed at surgery and one intracanalicular testes were not seen by MRI. The low signal intensity of the undescended testes on T{sub 2}-weighted images is indicative for fibrotic changes and may be of value for more accurate planning of the operative volume. MRI offers a new promising opportunity for localisation and morphologic estimation of the undescended testis and should be performed before the invasive investigation methods. (orig.) [Deutsch] Bei 22 maennlichen Patienten wurde eine MRT-Untersuchung zur Lokalisationsbestimmung von 27 nichttastbaren Hoden durchgefuehrt. Die operative Verifikation von 19 Hoden (15 Patienten) diente als Basis fuer die Ueberpruefung der Richtigkeit der MRT-Ergebnisse und fuer ihre Korrelation mit denen der Sonographie und Laparoskopie. Mittels MRT wurde der nichttastbare Hoden 13mal lokalisiert, dreimal wurde sein Fehlen richtig erfasst. Es gab drei falsche MRT-Diagnosen. Der Verdacht auf zwei intraabdominal gelegene Hoden wurde operativ nicht bestaetigt, ein Leistenhoden mit MRT nicht gesehen. Die niedrige Signalintensitaet des undeszendierten Hodens auf dem T{sub 2}-gewichteten Bild erklaert sich durch fibrotische Veraenderungen und kann von Wert fuer die genauere Planung des Operationsausmasses sein. MRT bietet eine neue vielversprechende Moeglichkeit fuer die Lokalisation und morphologische Bewertung des undeszendierten Hodens und sollte vor den invasiven diagnostischen Methoden eingesetzt werden. (orig.)

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

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    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

    auf. Beide Patienten ohne CJK wiesen die o.g. Signalveraenderungen nicht auf (Sensitivitaet 75%, Spezifitaet und positiver Vorhersagewert 100%). Schlussfolgerung: Werden CJK-Patienten mit FLAIR- und diffusionsgewichteten Sequenzen untersucht, so laesst sich die Erkrankung mit hoher Sicherheit nachweisen bzw. ausschliessen. Typische MRT-Befunde engen die Differenzialdiagnose ein und sollten in die WHO-Diagnosekriterien einbezogen werden. (orig.)

  7. Differentiation of benign osteoporotic and neoplastic vertebral compression fractures with a diffusion-weighted, steady-state free precession sequence.; Differenzierung osteoporotischer und tumoroeser Wirbelkoerperfrakturen mit einer diffusionsgewichteten Steady-State Free Precession-Sequenz

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    Baur, A.; Huber, A.; Nikolaou, K.; Staebler, A.; Reiser, M. [Inst. fuer Klinische Radiologie, Ludwigs-Maximilians-Universitaet Muenchen, Muenchen (Germany); Duerr, H.R. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Muenchen (Germany). Abt. fuer Orthopaedie; Deimling, M. [Siemens Medizinsysteme, Erlangen (Germany)

    2002-01-01

    Purpose: To evaluate the diagnosic accuracy of a diffusion-weigthed, steady-state free precession (SSFP) sequence for the differentiation of acute benign osteoporotic and neoplastic vertebral compression fractures. Methods: 85 patients with 102 vertebral compression fractures were examined with MR imaging using a spine array surface coil (Siemens, Vision, 1.5 Tesla). The following sequences were performed in sagittal orientation: T{sub 1}-weighted spin echo (SE), short-tau inversion recovery (STIR) and a diffusion-weighted SSFP sequence (TR=25 msec, diffusion pulse length {delta}=3 msec). The SSFP images were evaluated qualitatively on a 5-grade scale from strongly hypointense to strongly hyperintense. Quantitative analysis was performed with region of interest measurements (ROI) and calculation of a bone marrow ratio. Results: 60 fractures were due to osteoporosis and 42 fractures were caused by malignancy. 'Hyperintensity' in a vertebral fracture on a SSFP sequence provided a sensitivity of 100% and a specificity of 93%. The positive predictive value was 91%, the negative predictive value was 100%. Quantitative analysis of the bone marrow ratio showed a statistically significant difference between the osteoporosis and the tumor group (p<0.001). The mean value for the osteoporotic fractures was -0.32 (SD 0.33) and +2.07 (SD 1.37) for the tumor group. Conclusion: The SSFP sequence provides a high accuracy in the differentiation of benign osteoporotic and neoplastic vertebral compression fractures. (orig.) [German] Ziel: Ziel war die Ermittlung der diagnostischen Genauigkeit einer diffusionsgestuetzten steady-state free precession(SSFP)-sequenz fuer die Differenzierung von akuten osteoporotischen und tumoroesen Wirbelkoerperfrakturen. Methode: 85 Patienten mit 102 akuten Wirbelkoerperfrakturen wurden prospektiv mit der Magnetresonanztomographie (MRT) untersucht. Angewendet wurden eine T{sub 1}-gewichtete Spin Echo Sequenz, eine Short-tau inversion recovery

  8. MRI survival guide; MRT Basiskurs

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    Cardoza, J. [Alta Imaging Medical Group and Magnetic Imaging Affiliates, Berkeley, CA (United States); Herfkens, R.J. [eds.] [Stanford Univ., CA (United States). Medical Center

    1999-07-01

    The book is a German translation of an American textbook with the original title ''MRI Survival Guide'' and is intended to serve as an introductory guide for beginners or a reference book for quick information. Readers will find information on the fundamentals of the technology and methodology of MRI as well as all details of relevance to practice in a precise and easy-to-grasp arrangement, covering all anatomic areas of interest, illustrations and descriptions of characteristic signs of pathologic processes, high-quality and unusually large-sized diagnostic pictures, a modern didactic concept for quick orientiation, including surveys, tables, and reproductions for visualisation of contents. (orig./CB) [German] Praktisch jeder Mediziner wird im Laufe seiner Berufstaetigkeit mit der MRT konfrontiert - unabhaengig davon ob in der Radiologie, Orthopaedie, Gynaekologie, Chirurgie, Neurologie oder sonstigen Fachrichtung. Das Buch ist eine Uebersetzung eines amerikanischen Lehrbuches mit dem Originaltitel ''MRI Survival Guide'' und will eine wesentliche Erleichterung als 'Ueberlebenshandbuch fuer die MRT' bieten: - Darstellung aller relevanten Grundlagen zu Technik, verschiedenen Sequenzen und Methodik der MRT - knapp und mit maximalem Praxisbezug - Beruecksichtigung aller moeglichen Untersuchungsregionen und strukturierte Orientierung daran (Gehirn, Wirbelsaeule, Kopf/Nacken, Brustkorb, Bauch, Becken, Muskel-Skelett-Bereich) - Illustration und Beschreibung der charakteristischen Erscheinungsmerkmale aller haeufigen pathologischen Prozesse im MRT, inklusive direkt umsetzbarer differentialdiagnostischer Abgrenzungskriterien - hochwertiges und aussergewoehnlich gross dimensioniertes Bildmaterial - modernes, didaktisches Konzept fuer die rasche Orientierung mit vielen Uebersichten, Tabellen und Abbildungen zur Visualisierung der Inhalte, Praxistips und Aufzeigen von Fehlermoeglichkeiten - zum Einstieg, zur Rekapitulation

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

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    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.)

  10. MRT of the central nervous system; MRT des Zentralnervensystems

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    Forsting, M.; Jansen, O. (eds.)

    2006-07-01

    The book presents the state of the art of MRT imaging of the central nervous system. Detailed information is presented in order to provide sufficient knowledge for the medical diagnostician to discuss any case encountered at eye level with the clinical physician. The book is an indispensable reference manual and a quick orientation already during examination in difficult cases. It contains images made with the most recent technology and with excellent representation of details. Even rare findings are described in detail. The imaging principle is illustrated by more than 1000 pictures and graphical representations as well as more than 100 complementary tables. Findings are classified by regions, i.e. 'brain' and 'spinal cord', including anatomical descriptions. (orig.)

  11. 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)

  12. 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

  13. German PV-producers - an overview. Look back in humility; Photovoltaik Fabriken in Deutschland- eine Uebersicht. Blick zurueck in Demut

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    Iken, J.

    2001-03-01

    Three years are a long period of time in a growing field of industry like photovoltaic power generation. In January 1998, Sonne Wind and Waerme published the first list of German PV producers. The update is presented here. [German] Drei Jahre sind in einer Wachstumsbranche wie der Photovoltaik eine lange Zeit. Im Januar 1998 veroeffentlichte Sonne Wind and Waerme einen Ueberblick ueber die deutschen Photovoltaik-Fabriken. Hoechste Zeit also, die Uebersicht auf den neuesten Stand zu bringen. (orig.)

  14. 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

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

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    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.

  16. Radiofrequency of the liver. An update; Radiofrequenzablation der Leber. Eine aktuelle Uebersicht

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    Bangard, Christopher [Universitaetsklinikum Koeln (Germany). Inst. und Poliklinik fuer Radiologische Diagnostik

    2011-08-15

    The impact of radiofrequency ablation (RFA) as a local ablative tumor therapy is increasing. Randomized trials justify RFA for small hepatocellular carcinoma (HCC) (single tumor {<=} 5 cm or three or less tumors {<=} 3 cm). Surgical resection still remains the gold standard for resectable colorectal liver metastases (CRLM). Several single center trials demonstrate improved patient survival by RFA and justify RFA for non-resectable CRLM. Local recurrence increases significantly with tumor diameters > 3 cm. There is insufficient evidence at this time to resolve the issue of optimal approach for treatment of CRLM. Technical development of the electrode design, improved ablation algorithms, and simplification of the exact electrode placement by new real-time fusion techniques of pre-interventional CT or MRT images with intra-interventional ultrasound have the potential to reduce the variable and sometimes high rate of local tumor recurrence. The clinical impact of immunological aspects following RFA with regard to patient survival and local tumor recurrence remains unclear. (orig.)

  17. Differentiation of serous and purulent fluids in vitro and in vivo by means of diffusion-weighted MR imaging; Differenzierung seroeser und putrider Fluessigkeiten in vitro und in vivo mit diffusionsgewichteter MRT

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    Spuentrup, E.; Buecker, A.; Adam, G.; Guenther, R.W. [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik; Vaals, J.J. van [Philips Medical Systems, Best (Netherlands)

    2001-01-01

    Aim: The aim of this study was to test the feasibility for differentiation of serous fluid collections and abscess fluid with diffusion-weighted imaging and to compare three different diffusion sequences. Material and Methods: Thirteen puncture samples (6 serous, 7 purulent) and 19 patients with either serous fluid collections (n=12) or abscesses (n=7) were examined with diffusion-weighted spin-echo (SE), stimulated-echo (STE), and fat-suppressed SE (SE-SPIR) sequences. For in vitro studies 4 different b-factors (0, 87, 355, 798 s/mm{sup 2} in SE and SE-SPIR and 0, 51, 204, 460 s/mm{sup 2} in STE) were chosen and the apparent diffusion coefficient (ADC) was calculated. For in vivo measurements identical sequences with two b-factors (0,598 s/mm{sup 2} in SE and SE-SPIR and 0,360 s/mm{sup 2} in STE) were applied and the normalized signal attenuation was calculated. A navigator-echo technique and peripheral pulse triggering was used for motion artifact reduction. Results: The in vitro study yielded an ADC of serous fluid, which was close to that of free water, whereas for purulent fluid a significantly lower ADC was calculated. During in vivo examinations, serous fluids showed a strong signal attenuation (down to 22-32% of basic value) compared to a minor signal attenuation in purulent fluids (down to 86-94% of basic value) (p<0.05). Conclusions: In summary, with all three investigated diffusion schemes serous and purulent fluids can be clearly differentiated. (orig.) [German] Ziel: Das Ziel dieser Arbeit war es, die Moeglichkeit der Differenzierung seroeser und putrider Fluessigkeiten mit diffusionsgewichteter MRT zu untersuchen und drei verschiedene Sequenzschemata zu vergleichen. Material und Methoden: Hierzu wurden 13 Punktatproben (aus 6 seroesen und 7 putriden Fluessigkeitsansammlungen) sowie 19 Patienten (mit 12 seroesen und 7 putriden Fluessigkeitsansammlungen) mit einer diffusionsgewichteten Spin Echo-(SE), stimulierten Echo-(STE) und fettunterdrueckten SE

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

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    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.

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

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    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.

  20. MRI of pulmonary perfusion; MRT der Lungenperfusion

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    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.)

  1. Interactive MRT of the skeletomuscular system; MRT der Stuetz- und Bewegungsorgane. Interaktiv

    Energy Technology Data Exchange (ETDEWEB)

    Mauch, F.; Goldmann, A.; Mellerowicz, H.; Sell, I.; Sell, S. (eds.)

    2003-07-01

    Diagnostic imaging has gained immense importance in the treatment of orthopaedic diseases. However, in spite of its easy availability and wide range of options it should not be applied indiscriminately, especially in this age of rising cost pressure on the medical sector. This CD-ROM presents indications of MRT, technical aspects, and an outline of the normal and pathological MRT anatomy of the joints and spinal cord. The authors have experience with CD-ROM publications in ultrasonic diagnosis and draw on this experience in their attempt to provide an illustrative picture of the advantages and options of MRT imaging and its didactic aspects. (orig.) [German] Die Behandlung von orthopaedischen Erkrankungen wird immer differenzierter. Zentraler Bestandteil ist eine moderne und ausgefeilte klinische und bildgebende Diagnostik. Der Stellenwert der bildgebenden Diagnostik hat in der Gesamtschau des Behandlungsablaufes immens zu genommen. In vielen Bereichen stellt sie heute bereits eine diagnostische nicht invasive 'Gelenkspiegelung' dar. Die breite Verfuegbarkeit und die Moeglichkeiten stellen jedoch einen hohen Anspruch an den zielgerichteten Einsatz dieser Verfahren unter Beruecksichtigung des Kostendrucks der Medizin insgesamt. Der ungezielte, an dem klinischen Problem nicht orientierende, fast schon prophylaktische Einsatz wird der praxisorientierten Patientenversorgung nicht gerecht. Orthopaeden in interdisziplinaerer Kooperation mit radiologischen Kollegen ermoeglichen dieses Konzept. Die Vorerfahrungen der Herausgeber mit dem Medium CD-ROM im Bereich der Ultraschall-Diagnostik haben es erleichtert die besonderen Vorzuege und Moeglichkeiten in der Bilddarstellung und Didaktik dieses Mediums auszuschoepfen. (orig.)

  2. The diagnostic use of MRT in cases of suspected spondylitis; MRT-Differentialdiagnose bei Verdacht auf Spondylitis

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, K. [Inst. fuer Roentgendiagnostik, Klinikum rechts der Isar der Technischen Univ. Muenchen (Germany)

    1994-11-01

    In cases where MRT fails to reveal abscess formation or typical vertebral changes to confirm the preliminary diagnosis, further examinations are necessary to exclude diseases other than spondylitis. More remote possibilities like insufficiency fracture, rheumatic disorders and neoplasm can mostly be ruled out on the basis of conventional X-ray pictures. Conventional tomography and computed tomography should also be carried out in addition to MRT in the rare case of unconfirmed activated arthrosis or disc removal syndrome. In order to distinguish between infective and non-infective/reactive changes, contrast-enhanced repeat MRT following antibiotic treatment may be very helpful. (orig.) [Deutsch] Wenn bei einer Spondylitis ein dafuer beweisender Abszess oder eine typische Destruktion des Wirbelkoerpers nicht vorliegt, ist auch nach Durchfuehrung einer MRT oft eine differentialdiagnostische Abgrenzung gegenueber anderen Ursachen erforderlich. Ferner stehende Differentialdiagnosen wie Insuffizienzfraktur, rheumatische Erkrankungen und eine Neoplasie koennen mit den Moeglichkeiten des konventionellen Roentgenbildes meist ausgeschlossen werden. An die konventionelle- und Computertomographie sollte - auch nach Durchfuehrung der MRT - noch in unklaren Einzelfaellen von aktivierter Arthrose oder Postdisketomie-Syndrom gedacht werden. Eine gute differentialdiagnostische Moeglichkeit zur Unterscheidung zwischen einem Infekt und einem nicht infektioesen/reaktivem Geschehen ist die Wiederholungs-MRT mit KM-Applikation nach durchgefuehrter antibiotischer Behandlung. (orig.)

  3. 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

  4. MRI and MRS in patients with silicon implants of the breast; MRT und MRS nach Silikonaufbau der weiblichen Brust

    Energy Technology Data Exchange (ETDEWEB)

    Pfleiderer, B.; Heindel, W. [Muenster Univ. (Germany). Radiologische Klinik und Poliklinik

    2001-07-01

    This paper reviews the evaluation of the breast of women by MR-techniques after implantation with silicon gel protheses. The main topics are the diagnosis of implant defects such as extensive ''gel bleed'' and intra- and extracapsular ruptures. Moreover, the MR-detection of siliconomas (encapsulated silicone) and differentiation from malignomas as well as MR-features of chronic foreign body reactions are presented. ''Gel bleed'' is difficult to diagnose unambiguously by MRI alone. The ''linguini'' sign is the only reliable mans to diagnose intracapsular ruptures. The presence of silicone outside the implant capsule indicates extracapsular rupture. The MR-spectroscopic detection of silicone in the liver suggests after short implantation times and a normal MR scan the diagnosis ''gel bleed'', and after longer implantation times of more than 10 years and missing ''linguini'' sign the diagnosis of ruptures due to a dissolved shell of the implant. MRI, in comparison to other imaging modalities, has the highest specificity and sensitivity in the diagnosis of implant defects. Due to its high costs, however, MR is not suitable as a screening tool and should only be used in cases of sonographic suspected rupture or after radical mastectomy. In these cases MRI is the method of choice. (orig.) [German] In dieser Uebersicht wird die Evaluation der weiblichen Brust nach Aufbau mit Silikonmammaprothesen mittels MR-Techniken vorgestellt. Ein Schwerpunkt liegt dabei auf der Defektdiagnostik, d.h. dem Nachweis des so genannten ''Gelblutens'', der intra- und der extrakapsulaeren Ruptur. Daneben wird auf die MR-Detektion von Silikonomen (abgekapseltes Silikon) und deren Abgrenzung von einem Malignom eingegangen und das typische MR-Erscheinungsbild von chronischer Fremdkoerperreaktion vorgestellt. ''Gelbluten'' ist mittels MR-Bildgebung (MRT

  5. 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.

  6. 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

  7. 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).

  8. MRI in mucoviscidosis (cystic fibrosis); MRT bei Mukoviszidose

    Energy Technology Data Exchange (ETDEWEB)

    Eichinger, M.; Puderbach, M.; Kauczor, H.-U. [Deutsches Krebsforschungszentrum (DKFZ), Abteilung Radiologie, Heidelberg (Germany); Heussel, C.-P. [Universitaetsklinikum Mainz (Germany). Klinik und Poliklinik fuer Radiologie

    2006-04-15

    Cystic fibrosis (CF) is a multi-systemic disease with major impact on the lungs. Pulmonary manifestation is crucial for the prognosis and life expectancy of patients. Imaging modalities and lung function tests reflect the pulmonary status in these patients. The standard imaging modality for diagnosis and follow-up of pulmonary changes is chest x-ray. The gold standard for the detection of parenchymal lung changes remains high resolution computed tomography (HRCT), but this is not used routinely for CF-patients due to radiation exposure. Magnetic resonance imaging (MRI) used to be of no importance in monitoring cystic fibrosis lung disease, as shown in studies from the 1980s and early 1990s. The continuing improvement of MRI techniques, however, has allowed for an adequate application of this non-radiation method in diagnosing the major pulmonary findings in CF, in addition to the assessment of lung function. (orig.) [German] Die Lunge ist Hauptmanifestationsort der Mukoviszidose (zystischen Fibrose, CF) und entscheidend fuer Prognose und Lebenserwartung der Betroffenen. Bildgebende Verfahren spielen in der Diagnostik und Verlaufsbeurteilung der Lungenveraenderungen sowie dem Monitoring pulmonaler Komplikationen bei zystischer Fibrose eine wichtige Rolle. Obwohl die hochaufloesende Computertomographie (HRCT) als Goldstandard zur Beurteilung morphologischer Lungenveraenderungen bei zystischer Fibrose gilt, ist die Roentgenthoraxaufnahme aufgrund der geringeren Strahlenbelastung bei den meist jungen Patienten das derzeit eingesetzte Standardverfahren zur Diagnostik und Verlaufsbeurteilung. Die Magnetresonanztomographie (MRT) spielte bislang in der Diagnostik und Verlaufsbeobachtung der zystischen Fibrose keine Rolle, da Arbeiten aus den 80er und fruehen 90er Jahren keinen sinnvollen Beitrag der MRT zeigen konnten. Durch die kontinuierliche Verbesserung der Technik ist es seit neuestem erstmals moeglich, die MRT als Alternative fuer die Lungenbildgebung bei zystischer

  9. 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

  10. 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.)

  11. Magnetic resonance tomography and dental radiology (Dental-MRT); Die Magnetresonanztomographie in der Dentalradiologie (Dental-MRT)

    Energy Technology Data Exchange (ETDEWEB)

    Gahleitner, A. [Wien Univ. (Austria). Abt. fuer Osteologie; Wien Univ. (Austria). Abt. fuer Orale Chirurgie; Solar, P.; Ertl, L. [Wien Univ. (Austria). Abt. fuer Orale Chirurgie; Nasel, C.; Homolka, P. [Wien Univ. (Austria). Inst. fuer Biomedizinische Technik und Physik; Youssefzadeh, S.; Schick, S. [Wien Univ. (Austria). Abt. fuer Osteologie

    1999-12-01

    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.) [German] Ziel dieses Beitrags ist die Vorstellung der Untersuchungsmoeglichkeiten des Ober- und Unterkiefers mittels Magnetresonanztomographie (Dental-MRT) und ihre Anwendung bei der Diagnose zahnmedizinischer Erkrankungen. Sieben gesunde Probanden, 5 Patienten mit Pulpitis, 9 Patienten mit dentogenen Zysten, 5 Patienten nach Zahntransplantationen und 12 Patienten mit atrophem Unterkiefer wurden untersucht. Axiale T1- und T2-gewichtete Gradientenecho- und Spinecho-Sequenzen in 2D und 3D-Technik wurden durchgefuehrt. Nach der Untersuchung wurden zusaetzliche Panoramaschnitte und orhoradiale Rekonstruktionen des Ober- und Unterkiefers, unter Verwendung einer gebraeuchlichen Dental-Software, angefertigt. Der gesamte Ober- oder Unterkiefer, Zaehne, Pulpa und der Inhalt des Mandibularkanals koennen gut dargestellt werden. Patienten mit einer Entzuendung der

  12. 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.)

  13. 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

  14. Identification and quantification of fat compartments with CT and MRI and their importance; Identifikation und Quantifizierung von Fettkompartimenten mit CT und MRT und deren Stellenwert

    Energy Technology Data Exchange (ETDEWEB)

    Schlett, C.L.; Hoffmann, U. [Massachusetts General Hospital and Harvard Medical School, Department of Radiology, Cardiac MR PET CT Program, Boston, MA (United States)

    2011-05-15

    In addition to being overweight, as defined by the BMI, the distribution, composition and biological activity of adipose tissue are key elements in the cardiovascular risk stratification of patients. Several non-invasive techniques have been developed to quantify local fat depots, whereby computed tomography (CT) and magnetic resonance imaging (MRI) are the most important. In general adipose tissue is subdivided into subcutaneous and visceral compartments and although both are associated with cardiovascular risk factors and disease, visceral fat has on average a stronger association and a clearly higher biological activity independent of traditional risk factors. This maybe explained by the higher endocrine activity and secretion of pro-inflammatory cytokines by visceral fat. Especially pericardial adipose tissue, a local visceral fat depot surrounding the coronary arteries, is associated with the presence, extent and severity of coronary artery disease. However, several other local fat depots have been identified and associations with various diseases have been established. This article gives an overview over the current methods for the identification and quantification of local fat depots and summarizes the hypothesized and known associations. Furthermore, it gives an overview of the potential significance of individual local fat depots for cardiovascular risk stratification. (orig.) [German] Neben dem eigentlichen Uebergewicht, das durch den BMI definiert ist, spielen auch die Verteilung, Komposition und biologische Aktivitaet von Fettgewebe im menschlichen Koerper eine entscheidende Rolle bei der Risikostratifikation fuer kardiovaskulaere Erkrankungen. Verschiedene nichtinvasive Techniken stehen zur Verfuegung, um die unterschiedlichen Fettkompartimente zu identifizieren und quantifizieren. Dabei nehmen die Magnetresonanztomographie (MRT) und die Computertomographie (CT) einen besonderen Stellenwert ein, da diese Verfahren die Akquisition von 3D

  15. Modern MRI of the small bowell; Moderne MRT des Duenndarms

    Energy Technology Data Exchange (ETDEWEB)

    Scharitzer, M.; Ba-Ssalamah, A. [Medizinische Universitaet Wien, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Wien (Austria)

    2015-12-15

    variety of MR sequences has enabled not only the detection but also the characterization of pathological changes of the small intestine, which are vital for further treatment of these patients. (orig.) [German] Die radiologische Diagnostik von Erkrankungen des Duenndarms wurde in den letzten beiden Jahrzehnten einem dramatischen Wandel unterzogen. Durch rasche Fortschritte mit neuen Behandlungsmethoden und einem zunehmend therapeutischen Fokus auf transmuralen Heilungsprozessen ist eine Gesamtabklaerung des Gastrointestinaltrakts in den Mittelpunkt gerueckt. Durch die Einfuehrung der Endoskopie hat die gastrointestinale Bildgebung mit der Magen-Darm-Passage bzw. dem Enteroklysma mit einer relativ hohen Strahlenbelastung nur bedingte Einsatzmoeglichkeiten gezeigt. Die Entwicklung der Schnittbildverfahren ermoeglichte eine deutlich breitere radiologische Abklaerung abdomineller Erkrankungen. Durch schnelle Untersuchungstechniken sowie einen hohen Weichteilkontrast mit dem grossen Vorteil einer fehlenden Strahlenexposition hat die MRT des Gastrointestinaltrakts zunehmende Bedeutung gewonnen. Bei suffizienter Fuellung des Darmlumens liegt ein grosser Vorteil in der gleichzeitigen Abbildung saemtlicher Darmwandschichten, der perienteralen Strukturen sowie assoziierter abdomineller Veraenderungen. Neue MR-Sequenzen wie diffusionsgewichtete Sequenzen, dynamische Kontrastmittelsequenzen oder die MR-Fluoroskopie ermoeglichen die Detektion morphologischer Veraenderungen mit zusaetzlicher Charakterisierung dieser Darmabschnitte sowie die Beurteilung funktioneller Pathologien mit dynamischer Information ueber eine gestoerte Darmmotilitaet. Aktuelle Richtlinien europaeischer radiologischer und gastroenterologischer Organisationen haben die Bedeutung der Schnittbildverfahren und insbesondere der MRT fuer die Erstdiagnose und das Follow-up bei Patienten mit Morbus Crohn bestaetigt. Durch die Moeglichkeit der Beurteilung aller Darmwandschichten sowie dem Vorhandensein extramuraler

  16. 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.)

  17. 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

  18. Bestimmung von Größe und Größenänderung des linken Vorhofes : MRT und transthorakale Echokardiographie im Vergleich

    OpenAIRE

    Giesa, Christian

    2014-01-01

    Fragestellung Die Arbeit vergleicht MRT-Volumina des linken Vorhofes (LA) mit anderen Parametern aus Echokardiographie (TTE) und MRT, auch im zeitlichen Verlauf, sowie deren Reproduzierbarkeit. Methode Patienten mit Vorhofflimmern wurden ein bis drei Mal in MRT und TTE untersucht. Die Auswertung erfolgte retrospektiv aus einem Bildarchiv. Ergebnis Im MRT zeigt sich eine gute, im TTE eine deutlich schlechtere Reproduzierbarkeit. Am besten mit dem MRT-Volumen korreliert ...

  19. Cardiac functional analysis with MRI; Kardiale Funktionsanalyse mittels MRT

    Energy Technology Data Exchange (ETDEWEB)

    Sandner, T.A.; Theisen, D.; Bauner, K.U.; Picciolo, M.; Reiser, M.F.; Wintersperger, B.J. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany)

    2010-06-15

    Cardiovascular diseases (CVD) are among the leading causes of death worldwide. Even in the 21{sup st} century CVD will still be the most frequent cause of morbidity and mortality. Precise evaluation of cardiac function is therefore mandatory for therapy planning and monitoring. In this article the contribution of MRI-based analysis of cardiac function will be addressed. Nowadays cine-MRI is considered as the standard of reference (SOR) in cardiac functional analysis. ECG-triggered steady-state free precession (SSFP) sequences are mainly used as they stand out due to short acquisition times and excellent contrast between the myocardium and the ventricular cavity. An indispensible requirement for cardiac functional analysis is an exact planning of the examination and based on that the coverage of the whole ventricle in short axial slices. By means of dedicated post-processing software, manual or semi-automatic segmentation of the endocardial and epicardial contours is necessary for functional analysis. In this way end-diastolic volume (EDV), end-systolic volume (ESV) and the ejection fraction (EF) are defined and regional wall motion abnormalities (RWMA) can be detected. (orig.) [German] Weltweit gehoeren Herz-Kreislauf-Erkrankungen zu den haeufigsten Todesursachen. Auch im 21. Jahrhundert werden diese Erkrankungen das Erkrankungsspektrum und die Todesursachenstatistik anfuehren. Eine genaue Beurteilung der kardialen Funktion ist fuer die Therapieplanung und -ueberwachung unerlaesslich. In diesem Beitrag wird der Stellenwert der MRT bei der Beurteilung der kardialen Funktion eroertert. Als Standard der kardialen Funktionsanalyse kann heute die Cine-MRT angesehen werden, wofuer man ueberwiegend EGK-getriggerte Steady-state-free-precession- (SSFP-)Sequenzen einsetzt, die sich durch kurze Messzeiten und einen hervorragenden Kontrast zwischen Myokard und Ventrikelkavum auszeichnen. Voraussetzung fuer kardiale Funktionsuntersuchungen ist eine exakte Einstellung der

  20. Substituting environmentally relevant flame retardants: assessment fundamentals. Vol. 1: results and summary overview; Erarbeitung von Bewertungsgrundlagen zur Substitution umweltrelevanter Flammschutzmittel. Bd. 1: Ergebnisse und zusammenfassende Uebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Leisewitz, A.; Kruse, H.; Schramm, E.

    2001-04-01

    /Elektronik, Schienenfahrzeugbereich, Textil-/Polstermoebelindustrie. Parallel dazu werden dreizehn Flammschutzmittel hinsichtlich Mengenstrom, Anwendungen und Toxikologie/Oekotoxikologie charakterisiert. Bd. I: Ergebniszusammenfassung zu Flammschutzmitteleinsatz in Deutschland 1999/2000; Charakterisierung von 13 FSM nach Stoff- und Anwendungseigenschaften, Einsatzspektrum, Mengen; Ableitung von Bewertungsgrundlagen fuer FSM mit Schwergewicht auf Toxikologie/Oekotoxikologie, Kreislauffaehigkeit, Substitutions- und Minderungspotentialen; zusammenfassende Stoffbewertung zu 13 FSM; zusammenfassende Uebersicht zu FSM-Anwendungen. Bd. II: Anwendungsuntersuchungen (Stand der Technik, Trend, Alternativen) zu FSM bei UP-Harzen (Schienenfahrzeuge), bei PU-Daemm- und Montageschaeumen (Baubereich); bei Kunststoffen fuer E+E-Geraete insgesamt, Aussengehaeusen fuer E+E-Geraete und Leiterplatten (Elektro/Elektronikindustrie); bei Polstermoebeln/Matratzen (Textilanwendungen). Bd. III: Toxikologisch/oekotoxikologische Stoffprofile Decabromdiphenylether, Tetrabrombisphenol A; Bis[pentabromphenyl]ethan; Hexabromcyclododecan, Tris[chlorpropyl]phosphat, Resorcinol-bis-diphenyl-phosphat; N-Hydroxymethyl-3-dimethylphosphonpropionamid, roter Phosphor, Ammoniumpolyphosphat, Melamincyanurat, Aluminiumtrihydroxid, Borax, Antimontrioxid. (orig.)

  1. 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

  2. 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.)

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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

  9. Applicability of TOD, MTDP, MRT and DMRT for dynamic image enhancement techniques

    NARCIS (Netherlands)

    Bijl, P.; Schutte, K.; Hogervorst, M.A.

    2006-01-01

    Current end-to-end sensor performance measures such as the TOD, MRT, DMRT and MTDP were developed to describe Target Acquisition performance for static imaging. Recent developments in sensor technology (e.g. microscan) and image enhancement techniques (e.g. Super Resolution and Scene-Based

  10. 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).

  11. The Effect of External Magnetic Fields on the MRT Instability in MagLIF

    Science.gov (United States)

    Hess, Mark; Peterson, Kyle; Weis, Matthew; Lau, Yue Ying

    2014-10-01

    Recent experiments on MagLIF which incorporate an external B-field suggest that the MRT instability within the liner has a different behavior than without the B-field. Previous work by Chandrasekhar and Harris have illustrated how the MRT growth rate, assuming fixed liner density and fixed acceleration, can change due to the presence of an external B-field. In this work, we show how the growth rate of the MRT instability is dynamically affected by the rapidly varying acceleration, liner density, and surface magnetic field, which is composed of the external B-field and the drive B-field of the liner in the MagLIF experiments. In addition, we also examine the effects of finite liner resistivity on MRT growth, which gives rise to an additional time scale corresponding to magnetic diffusion. We discuss the implications of this result for future MagLIF designs. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000.

  12. The role of MRI in suspected inner ear malformations; Stellenwert der MRT bei Verdacht auf Innenohrmissbildung

    Energy Technology Data Exchange (ETDEWEB)

    Koesling, S.; Juettemann, S.; Amaya, B. [Halle-Wittenberg Univ., Halle (Germany). Klinik fuer Diagnostische Radiologie; Rasinski, C.; Bloching, M. [Halle-Wittenberg Univ., Halle (Germany). Klinik fuer Hals-, Nasen-, Ohrenkrankheiten; Koenig, E. [Leipzig Univ. (Germany). Klinik fuer Hals-, Nasen-, Ohrenkrankheiten

    2003-12-01

    Purpose: This is a prospective analysis of the value of MRI in suspected inner ear malformations. Materials and Methods: In 50 patients (43 children and young adults, 7 adults) with suspected inner ear malformation MRI (1.5 T) was performed. In addition, 42 of these patients underwent CT. For the analysis of the inner ear structures, the constructive interference in steady state (CISS) sequence with 0.7 mm slice thickness was used. Functional tests revealed a sensorineural hearing loss or deafness in 82 temporal bones (TB) and a combined hearing loss in 4 TB. The hearing loss was unilateral in 14 patients. MRI and CT findings were compared. Results: Imaging findings were normal in 58 TB. The pathological findings included inner ear malformations (35 TB), inflammatory changes (4 TB), partial obliteration of labyrinth (2 TB) and congenital aural atresia (1 TB). An isolated absence of the cochlear nerve (1 TB) could only be found by MRI. In the remaining cases, an inner ear malformation was diagnosed by MRI and CT with the same confidence but MRI was superior in displaying the fine details. Conclusions: MRI will become the method of choice in the diagnosis of inner ear malformations. (orig.) [German] Ziel: Das Ziel der Arbeit bestand in einer prospektiven Analyse des Stellenwertes der MRT bei Verdacht auf eine Innenohrmissbildung. Material und Methodik: 50 Patienten (43 Kinder und Jugendliche, 7 Erwachsene) mit dringendem Verdacht auf eine Innenohrmissbildung erhielten eine MRT-Untersuchung (1,5 T), bei 42 dieser Patienten wurde auch eine CT durchgefuehrt. Bei der Beurteilung der Innenohrstrukturen kam die CISS-Sequenz mit einer Schichtdicke von 0,7 mm zur Anwendung. Durch Funktionstests wurde an 82 Schlaefenbeinen (SB) eine Innenohrhoerstoerung und an 4 SB eine kombinierte Hoerstoerung diagnostiziert. 14 Patienten hatten eine einseitige Hoerstoerung. MRT- und CT-Ergebnisse wurden verglichen. Ergebnisse: Einen bildgebenden Normalbefund wiesen 58 SB auf. Folgende

  13. 3D Bildgebung von zerebralen Aneurysmen Vergleich zwischen CT und MRT

    Science.gov (United States)

    Goubergrits, Leonid; Pöthke, Jens; Petz, Christoph; Hege, Hans-Christian; Spuler, Andreas; Kertzscher, Ulrich

    Patientenspezifische Strömungs- und die Geometrieanalyse von Aneurysmen basiert auf der 3D-Rekonstruktion aus Daten, die mit modernen Methoden der Bildgebung (z.B. CT und MRT) gewonnen werden. Die unterschiedlichen Charakteristika der Bildgebungsverfahren und die damit verbundenen Unsicherheiten führen zu Variationen der rekonstruierten Geometrien, die sich auf die numerische Berechnung von Strömungsparametern, wie z.B. die Wandschubspannung, auswirken können. Basierend auf CT- und MRT-Aufnahmen eines anatomisch realistischen Referenzmodells eines zerebralen Aneurysmas der Arteria Basilaris vergleichen wir die rekonstruierten Geometrien und die hierin simulierten Blutströmungen. Die Segmentierung und Rekonstruktion des Aneurysmas erfolgte mit Hilfe des Programms AMIRA. Die numerischen Strömungsberechnungen wurden mit dem Strömungslöser FLUENT durchgeführt.

  14. 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.)

  15. 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.)

  16. 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

  17. MRT diagnosis of intra- and paraspinal abscesses; Kernspintomographische Diagnostik intra- und paraspinaler Abszesse

    Energy Technology Data Exchange (ETDEWEB)

    Lanfermann, H. [Inst. und Poliklinik fuer Radiologische Diagnostik, Univ. Koeln (Germany); Heindel, W. [Inst. und Poliklinik fuer Radiologische Diagnostik, Univ. Koeln (Germany); Gierenz, M. [Inst. und Poliklinik fuer Radiologische Diagnostik, Univ. Koeln (Germany); Haupt, W.F. [Klinik und Poliklinik fuer Neurologie, Univ. Koeln (Germany); Hildebrandt, G. [Klinik und Poliklinik fuer Neurochirurgie, Univ. Koeln (Germany); Lackner, K. [Inst. und Poliklinik fuer Radiologische Diagnostik, Univ. Koeln (Germany)

    1996-07-01

    Analysis of the MRT signals and their extent from intra- and paraspinal abscesses with reference to predisposing factors, their causes and localisation. The histories and MRT findings in 34 Patients with intra- and paraspinal abscesses were evaluated retrospectively. Most of the patients (24/34) were older than 50 years. A second peak was below 30 years. 27/34 patients had some underlying disease which predisposed to infection, e.g., diabetes mellitus. The most common causal organisms were Staph. aureus (53%) and streptococci (15%). In 23/34 cases (68%), the abscesses were in the thoraco-lumbar or lumbar region, while only 6/34 occurred in the upper two-thirds of the thoracic spine and only 5/34 in the cervical region. In only 8/34 was the abscess confined to two vertebral lengths; in the remaining patients it was much more extensive. Intraspinal abscesses were about twice as large as the vertebral components and 1.5 times greater than paravertebral abscesses. The age of the abscesses could be estimated approximately from the signals. Contrast enhanced MRT permits detailed analysis of the compartments and exact estimation of the extent of the lesions and permits accurate monitoring of treatment. (orig.) [Deutsch] MR-tomographische Analyse des Signal- und Ausbreitungsverhaltens intra- und paraspinaler Abszesse unter Beruecksichtigung praedisponierender Faktoren, des Erregerspektrums und der Lokalisation. Die Krankengeschichten und MRT von 34 Patienten mit intra- und paraspinalen Abszessen wurden retrospektiv ausgewertet. Die Mehrzahl der Patienten (24/34) war aelter als 50 Jahre. Ein zweiter Altersgipfel lag bei unter 30 Jahren. 27/34 Patienten litten an Grunderkrankungen, die Infektionen beguenstigen, wie zum Beispiel Diabetes mellitus. Die haeufigsten Erreger waren Staphylococcus aureus (53%) und Streptokokken (15%). Die Abszesse waren in 23/34 Faellen (68%) im thorakolumbalen Uebergang und lumbal lokalisiert, waehrend die oberen zwei Drittel der BWS nur bei 6

  18. 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.)

  19. MRT of scaphoid pseudo-arthrosis using Gd-DTPA. Staging and clinical correlation; MRT der Skaphoidpseudarthrose mit Gd-DTPA. Stadieneinteilung und klinische Korrelation

    Energy Technology Data Exchange (ETDEWEB)

    Vogl, T.J. [Freie Univ. Berlin (Germany). Strahlenklinik und Poliklinik; Beutel, F. [Freie Univ. Berlin (Germany). Strahlenklinik und Poliklinik; Wilhelm, K. [LMU Muenchen (Germany). Abt. fuer Handchirurgie; Tempka, A. [Freie Univ. Berlin (Germany). Klinik fuer Unfall- und Wiederherstellungschirurgie; Schedel, H. [Freie Univ. Berlin (Germany). Strahlenklinik und Poliklinik; Haas, R. [Freie Univ. Berlin (Germany). Strahlenklinik und Poliklinik; Felix, R. [Freie Univ. Berlin (Germany). Strahlenklinik und Poliklinik

    1994-11-01

    During a period of two years, 134 patients with pseudo-arthrosis of the scaphoid were examined by conventional radiography and by MRI in the course of a prospective study. The aim of the study was to define radiological staging using contrast enhanced MRI in order to improve the prognostic criteria. All MRI examinations were carried out with a 1.5 Tesla scanner (SP63) using a surface coil and T{sub 1} weighted spin echo sequences in sagittal and frontal projection and frontal FLASH T{sub 2}-sequences and axial spin echo T{sub 2} sequences. The T{sub 1} weighted SE sequences in frontal projection were carried out before and after iv contrast (0.1 mmol Gd-DTPA/kg KG). All sequences were compared with conventional radiographs and the operative findings. Eight patients in stage 0 showed high signal intensity of both fragments in T{sub 1} weighted SE sequences and at surgery there was good vascularisation. In 22 cases there was reduced signal intensity in at least one fragment (stage I). 45 patients with scaphoid pseudo-arthrosis showed complete signal loss but marked contrast uptake with still vital nuclei at surgery (stage II). In 22 patients, there was no increase in signal intensity after contrast and complete loss of vitality of the fragments at surgery. Staging was not possible in 37 patients because of previous operative intervention. The use of contrast enhanced MRI provides additional information compared with conventional radiography or plain MRI. (orig.) [Deutsch] Im Rahmen einer prospektiven Studie wurden in einem Zeitraum von 2 Jahren 134 Patienten mit einer Skaphoidpseudarthrose (SPA) vergleichend konventionell roentgenologisch und magnetresonanztomographisch untersucht. Ziel der Studie war die Erstellung einer klinisch radiologischen Stadieneinteilung mit Hilfe der kontrastverstaerkten MRT zur Verbesserung von Prognosekriterien. Alle MRT-Untersuchungen wurden an einem 1,5 Tesla-Geraet (SP63) mittels einer Oberflaechenspule unter Verwendung von T{sub 1

  20. 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

  1. 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

  2. Influence of polarization and a source model for dose calculation in MRT

    Energy Technology Data Exchange (ETDEWEB)

    Bartzsch, Stefan, E-mail: s.bartzsch@dkfz.de; Oelfke, Uwe [The Institute of Cancer Research, 15 Cotswold Road, Belmont, Sutton, Surrey SM2 5NG, United Kingdom and Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, D-69120 Heidelberg (Germany); Lerch, Michael; Petasecca, Marco [Centre for Medical Radiation Physics, University of Wollongong, Northfields Avenue, Wollongong 2522 (Australia); Bräuer-Krisch, Elke [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38000 Grenoble (France)

    2014-04-15

    Purpose: Microbeam Radiation Therapy (MRT), an alternative preclinical treatment strategy using spatially modulated synchrotron radiation on a micrometer scale, has the great potential to cure malignant tumors (e.g., brain tumors) while having low side effects on normal tissue. Dose measurement and calculation in MRT is challenging because of the spatial accuracy required and the arising high dose differences. Dose calculation with Monte Carlo simulations is time consuming and their accuracy is still a matter of debate. In particular, the influence of photon polarization has been discussed in the literature. Moreover, it is controversial whether a complete knowledge of phase space trajectories, i.e., the simulation of the machine from the wiggler to the collimator, is necessary in order to accurately calculate the dose. Methods: With Monte Carlo simulations in the Geant4 toolkit, the authors investigate the influence of polarization on the dose distribution and the therapeutically important peak to valley dose ratios (PVDRs). Furthermore, the authors analyze in detail phase space information provided byMartínez-Rovira et al. [“Development and commissioning of a Monte Carlo photon model for the forthcoming clinical trials in microbeam radiation therapy,” Med. Phys. 39(1), 119–131 (2012)] and examine its influence on peak and valley doses. A simple source model is developed using parallel beams and its applicability is shown in a semiadjoint Monte Carlo simulation. Results are compared to measurements and previously published data. Results: Polarization has a significant influence on the scattered dose outside the microbeam field. In the radiation field, however, dose and PVDRs deduced from calculations without polarization and with polarization differ by less than 3%. The authors show that the key consequences from the phase space information for dose calculations are inhomogeneous primary photon flux, partial absorption due to inclined beam incidence outside

  3. Diffusion-weighted MRI of the prostate; Diffusionsgewichtete MRT der Prostata

    Energy Technology Data Exchange (ETDEWEB)

    Mueller-Lisse, U.G.; Scherr, M.K. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Klinische Radiologie, Muenchen (Germany); Mueller-Lisse, U.L. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Klinik und Poliklinik fuer Urologie, Muenchen (Germany); Zamecnik, P.; Schlemmer, H.P.W. [Deutsches Krebsforschungszentrum (DKFZ), Abteilung fuer Radiologische Diagnostik, Heidelberg (Germany)

    2011-03-15

    Diffusion-weighted magnetic resonance imaging (DWI) can complement MRI of the prostate in the detection and localization of prostate cancer, particularly after previous negative biopsy. A total of 13 original reports and 2 reviews published in 2010 demonstrate that prostate cancer can be detected by DWI due to its increased cell density and decreased diffusiveness, either qualitatively in DWI images or quantitatively by means of the apparent diffusion coefficient (ADC). In the prostate, the ADC is influenced by the strength of diffusion weighting, localization (peripheral or transitional zone), presence of prostatitis or hemorrhage and density and differentiation of prostate cancer cells. Mean differences between healthy tissue of the peripheral zone and prostate cancer appear to be smaller for ADC than for the (choline + creatine)/citrate ratio in MR spectroscopy. Test quality parameters vary greatly between different studies but appear to be slightly better for combined MRI and DWI than for MRI of the prostate alone. Clinical validation of DWI of the prostate requires both increased technical conformity and increased numbers of patients in clinical studies. (orig.) [German] Die diffusionsgewichtete MRT (''diffusion-weighted imaging'', DWI) kann die MRT der Prostata bei der Erkennung und Lokalisation von Prostatakarzinomen besonders nach vorangehender, negativer Stanzbiopsie ergaenzen. In 13 klinischen Original- und 2 Uebersichtsarbeiten des Jahres 2010 zeigt sich, dass die DWI Prostatakarzinome an Einschraenkungen der freien Teilchenbeweglichkeit bei erhoehter Zelldichte qualitativ im Bild oder quantitativ an Hand des ''apparent diffusion coefficient'' (ADC) nachweist. Den ADC in der Prostata beeinflussen Staerke der Diffusionsgewichtung, Lokalisation (periphere Zone, Transitionalzone), Vorliegen von Prostatitis oder Einblutung sowie Streudichte und Differenzierung von Prostatakarzinomzellen. Unterschiede zwischen gesundem

  4. Manipulator for the therapy of breast cancer in the magnetic-resonance-tomography-device (MRT)

    International Nuclear Information System (INIS)

    Fischer, H.; Selig, M.; Vagner, J.; Kaiser, W.A.

    2000-01-01

    A significant progress has been achieved in the diagnosis of small sized mamma carcinomas by magnetic resonance mammography. Diagnosis and therapy in one turn using the same machine would enhance precision and reduce cost of the intervention, minimizing the patient's strain and side effects. A manipulator with a biopsy unit will be presented allowing the combination of diagnostic imaging with biopsy and subsequent therapy. Tests have shown that a marked target could be reached reproducibly. It was placed within a pig liver in the isocenter of a MRT running with a magnetic field of 1.5 T. (orig.)

  5. Functional MR imaging of the patellofemoral joint; Funktionelle MRT des Femoropatellargelenkes

    Energy Technology Data Exchange (ETDEWEB)

    Muhle, C. [Klinik fuer Radiologische Diagnostik, Kiel Univ. (Germany); Brossmann, J. [Klinik fuer Radiologische Diagnostik, Kiel Univ. (Germany); Heller, M. [Klinik fuer Radiologische Diagnostik, Kiel Univ. (Germany)

    1995-02-01

    Conventional X-ray examinations of the patellofemoral joint in 30 , 60 and 90 of knee flexion demonstrate the position of the patella. On the other hand, they have been shown to be insufficient for the diagnosis of patellofemoral maltracking in the critical range between 30 of flexion and full extension. Motion-triggered and ultrafast MRI offer new possibilities for functional diagnosis of the patellofemoral joint under active knee motion. Functional MRI of the patellofemoral joint is suggested as an alternative to arthroscopy, particularly in patients with anterior knee pain or suspected patellar maltracking. (orig.) [Deutsch] Tangentialaufnahmen der Patella in 30 -, 60 - und 90 -Kniebeugung koennen zwar die Lage der Kniescheibe im Femoropatellargelenk darstellen, sie erlauben jedoch keine Aussage ueber die funktionellen Aspekte des Patellagleitens zwischen 30 -Beugung und 0 -Streckung. Dieser fuer die Kniescheibenfuehrung kritische, mittels der konventionellen Roentgentechnik (aufgrund von Femur- und Patellaueberlagerung) nicht einsehbare Bereich, kann unter aktiver Kniestreckung mit der funktionellen MRT dargestellt werden. Durch bewegungsgetriggerte Gradientenechosequenzen oder neuerdings auch durch ultraschnelle Bildsequenzen ist es moeglich, funktionelle Informationen ueber das Patellagleiten in der endgradigen Streckenbewegung zu erhalten. Die funktionelle MRT des Femorpatellargelenkes bietet daher z.B. fuer die Abklaerung von unklaren, vorderen Kniegelenksbeschwerden und bei der Frage nach Patellagleitwegsstoerungen eine Alternative zur diagnostischen Arthroskopie. (orig.)

  6. 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

  7. 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.

  8. 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

  9. 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.)

  10. Medical physics aspects of the synchrotron radiation therapies: Microbeam radiation therapy (MRT) and synchrotron stereotactic radiotherapy (SSRT).

    Science.gov (United States)

    Bräuer-Krisch, Elke; Adam, Jean-Francois; Alagoz, Enver; Bartzsch, Stefan; Crosbie, Jeff; DeWagter, Carlos; Dipuglia, Andrew; Donzelli, Mattia; Doran, Simon; Fournier, Pauline; Kalef-Ezra, John; Kock, Angela; Lerch, Michael; McErlean, Ciara; Oelfke, Uwe; Olko, Pawel; Petasecca, Marco; Povoli, Marco; Rosenfeld, Anatoly; Siegbahn, Erik A; Sporea, Dan; Stugu, Bjarne

    2015-09-01

    Stereotactic Synchrotron Radiotherapy (SSRT) and Microbeam Radiation Therapy (MRT) are both novel approaches to treat brain tumor and potentially other tumors using synchrotron radiation. Although the techniques differ by their principles, SSRT and MRT share certain common aspects with the possibility of combining their advantages in the future. For MRT, the technique uses highly collimated, quasi-parallel arrays of X-ray microbeams between 50 and 600 keV. Important features of highly brilliant Synchrotron sources are a very small beam divergence and an extremely high dose rate. The minimal beam divergence allows the insertion of so called Multi Slit Collimators (MSC) to produce spatially fractionated beams of typically ∼25-75 micron-wide microplanar beams separated by wider (100-400 microns center-to-center(ctc)) spaces with a very sharp penumbra. Peak entrance doses of several hundreds of Gy are extremely well tolerated by normal tissues and at the same time provide a higher therapeutic index for various tumor models in rodents. The hypothesis of a selective radio-vulnerability of the tumor vasculature versus normal blood vessels by MRT was recently more solidified. SSRT (Synchrotron Stereotactic Radiotherapy) is based on a local drug uptake of high-Z elements in tumors followed by stereotactic irradiation with 80 keV photons to enhance the dose deposition only within the tumor. With SSRT already in its clinical trial stage at the ESRF, most medical physics problems are already solved and the implemented solutions are briefly described, while the medical physics aspects in MRT will be discussed in more detail in this paper. Copyright © 2015. Published by Elsevier Ltd.

  11. Clinical value of kinematic MR imaging in the evaluation of patients with exacerbated pain in cervical spine motion; Stellenwert der kinematischen MRT der Halswirbelsaeule bei bewegungsabhaengigen Radikulopathien im Vergleich zur statischen MRT

    Energy Technology Data Exchange (ETDEWEB)

    Muhle, C. [Kiel Univ. (Germany). Klinik fuer Nuklearmedizin; Brossmann, J.; Biederer, J.; Grimm, J.; Mohr, A.; Heller, M. [Kiel Univ. (Germany). Klinik fuer Diagnostische Radiologie

    2001-02-01

    Objective: To assess the clinical value of kinematic MR imaging in patients with cervical radiculopathy and increasing symptoms after provocative maneuvers at flexion, extension, axial rotation and coupled motion of the cervical spine. Methods: Thirty-five patients with cervical disc herniation or cervical spondylosis in whom symptoms were elicited at flexion, extension, axial rotation and coupled motion were studied inside a positioning device using T{sub 2}-weighted TSE, 2D-FLASH, and reformatted 3D DESS and 3D-FISP sequences. The images were evaluated for the size of disc herniations, the foraminal size and cervical cord displacement at provocative position compared with neutral position (0 ). In addition, the value of kinematic MR images were interpretated with regard to changes in the therapeutic procedure and intraoperative patient positioning. Results: Compared with the neutral position (0 ) a change in disc herniations was not found in any (0%) of the provocative positions. In five patients (14%) cervical cord displacement was noted at axial rotation. The foraminal size varied depending on the provocative position, increasing at flexion and decreasing at extension. Conclusion: Kinematic MR imaging in patients with cervical radiculopathy and increasing symptoms at provocative maneuvers provides no additional information for the therapeutic decision-making process. (orig.) [German] Ziel: Bewertung des klinischen Stellenwertes der kinematischen MRT im Vergleich zur statischen MRT Untersuchung in der Abklaerung von Patienten mit bewegungsabhaengigen, zervikalen Radikulopathien. Methode: 35 Patienten mit bewegungsabhaengigen Zervikobrachialgien wurden innerhalb eines Positionsgestells in der Neutralnullstellung (0 ) sowie in der Schmerzprovokationsstellung unter Verwendung einer sagittalen T{sub 2}-gewichteten TSE Sequenz, einer axialen T{sub 2}-gewichteten 2D-FLASH Sequenz sowie einer schraeg-koronar rekonstruierten 3D-FISP- und 3D-DESS Sequenz bei 1,5 Tesla

  12. 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

  13. Multiparametric prostate MRI for follow-up monitoring after radiation therapy; Multiparametrische MRT der Prostata zum Therapiemonitoring nach Strahlentherapie

    Energy Technology Data Exchange (ETDEWEB)

    Weidner, A.M.; Dinter, D.J.; Bohrer, M.; Sertdemir, M.; Hausmann, D.; Wenz, F.; Schoenberg, S.O. [Universitaetsmedizin Mannheim, Medizinische Fakultaet Mannheim der Universitaet Heidelberg, Institut fuer Klinische Radiologie und Nuklearmedizin, Mannheim (Germany)

    2012-03-15

    Radiation therapy is a therapeutic option with curative intent for patients with prostate cancer. Monitoring of prostate-specific antigen (PSA) values is the current standard of care in the follow-up. Imaging is recommended only for symptomatic patients and/or for further therapeutic options. For detection of local recurrence magnetic resonance imaging (MRI) of the prostate is acknowledged as the method of choice. Good results for primary diagnosis were found especially in combination with functional techniques, whereas in recurrent prostate cancer only few studies with heterogeneous study design are available for prostate MRI. Furthermore, changes in different MRI modalities due to radiation therapy have been insufficiently investigated to date. As the initial results were promising prostate MRI and available therapeutic options for detection of local recurrence should be considered in patients with increased PSA. (orig.) [German] Fuer Patienten mit Prostatakarzinom stellt die Radiatio eine potenziell kurative lokale Therapieoption dar. Im Rahmen der Nachsorge nach lokal kurativ intendierter Therapie wird aktuell der Verlauf des PSA-Werts (PSA prostataspezifisches Antigen) kontrolliert, der Einsatz bildgebender Verfahren wird lediglich bei symptomatischen Patienten und/oder zur Planung einer Salvagetherapie empfohlen. Die MRT der Prostata stellt derzeit die Methode der Wahl zur lokalen Rezidivdiagnostik dar. Insbesondere in Verbindung mit funktionellen Untersuchungstechniken zeigen Studien gute Ergebnisse in der Primaerdiagnostik. Zum Einsatz der MRT der Prostata in der Rezidivsituation wurden bisher nur wenige Studien mit heterogenem Studiendesign publiziert. Auch die in der MRT nach Bestrahlung sichtbaren Veraenderungen in den unterschiedlichen Modalitaeten sind noch wenig evaluiert. Da die ersten Studienergebnisse auch bei Patienten nach Radiatio viel versprechend sind, sollte bei unklarem PSA-Anstieg und vorhandener Therapieoption eine MRT der Prostata zur

  14. 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.)

  15. 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.)

  16. 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.

  17. Magnetic resonance tomography-guided interventional procedure for diagnosis of prostate cancer; MRT-gezielte interventionelle Verfahren zur Abklaerung des Prostatakarzinoms

    Energy Technology Data Exchange (ETDEWEB)

    Schernthaner, M.; Helbich, T.H.; Fueger, B.J.; Memarsadeghi, M.; Stiglbauer, A.; Linhart, H.G.; Doan, A.; Pinker, K.; Brader, P. [Medizinische Universitaet Wien, Univ.-Klinik fuer Radiodiagnostik, Division fuer Molekulare und Gender-Bildgebung, Wien (Austria); Margreiter, M. [Medizinische Universitaet Wien, Univ.-Klinik fuer Urologie, Wien (Austria)

    2011-11-15

    In recent years magnetic resonance imaging (MRI) has been increasingly established in the diagnosis of prostate cancer in addition to transrectal ultrasonography (TRUS). The use of T2-weighted imaging allows an exact delineation of the zonal anatomy of the prostate and its surrounding structures. Other MR imaging tools, such as dynamic contrast-enhanced T1-weighted imaging or diffusion-weighted imaging allow an inference of the biochemical characteristics (multiparametric MRI). Prostate cancer, which could only be diagnosed using MR imaging or lesions suspected as being prostate cancer, which are localized in the anterior aspect of the prostate and were missed with repetitive TRUS biopsy, need to undergo MR guided biopsy. Recent studies have shown a good correlation between MR imaging and histopathology of specimens collected by MR-guided biopsy. Improved lesion targeting is therefore possible with MR-guided biopsy. So far data suggest that MR-guided biopsy of the prostate is a promising alternative diagnostic tool to TRUS-guided biopsy. (orig.) [German] Neben dem transrektalen Ultraschall (TRUS) hat sich in den letzten Jahren die MRT als nichtinvasive Methode zur Bildgebung von Prostatatumoren etabliert. Mittels T2-gewichteter Sequenzen ist eine exakte anatomische Darstellung der Prostata und ihrer umliegenden Strukturen moeglich. Andere MRT-Techniken ermoeglichen Rueckschluesse auf das biologische Verhalten des Tumors: dynamische kontrastmittelverstaerkte T1-gewichtete Sequenzen zur Darstellung der Angiogenese, diffusionsgewichtete Aufnahmen zur Beurteilung der Zelldichte und die Spektroskopie zur Bestimmung von Gewebemetaboliten wie Cholin und Kreatin (multiparametrische Bildgebung). Prostatatumoren, die nur mittels MRT nachweisbar sind oder verdaechtige Tumoren, die hauptsaechlich anterior in der Prostata lokalisiert sind und in wiederholten TRUS-gezielten Biopsien verfehlt wurden, benoetigen eine MRT-gezielte Biopsie zur Diagnosesicherung. Die bisherigen

  18. 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

    A clinical evaluation of hydro-MRI as an alternative method to barium studies in children with abdominal pain of unknown origin is presented. Patients and Methods: 20 children with abdominal pain of unknown origin aged from 9 - 16 years were examined after oral bowel opacification using 1000 ml of 2.5% mannitol solution with a 1.0T MRI system. The investigation was done in 2 planes (coronal and axial) under breath-hold conditions. Imaging procedures included various sequences (T2W HASTE + FS, contrast-enhanced T1W FLASH FS). Suspicious findings in bowel segments and extra-intestinal changes were assessed. Results: In 21/24 examinations the small bowel was completely visualized, in 15/24 cases colon segments were identified. An accurate assessment of the terminal ileum was not possible in 3/24 procedures. Breathing artefacts occurred in 3/24 examinations. Signs of Crohn's disease were found in 4 examinations, inflammatory changes of the ileum were detected in 3 cases. Inflammation of the colon was demonstrated in 2 children. Furthermore, pathological findings included constipation in one child and inflammation of the ileo-colic and mesenterial lymph nodes were found in another child. Extra-intestinal changes in 3 children were caused by ovarian cysts, and in one case by pleural effusion. In 4 examinations we detected ascites in the absence of other pathological findings. In 5 children there was no pathological correlation in the bowel or extra-intestinal region for the complaints. The children tolerated the hydro-MRI very well. There were no side effects using oral mannitol. (orig.) [German] Ziel: Klinische Evaluation der Hydro-MRT bei Kindern mit unklarer abdomineller Symptomatik als alternative Methode zur fraktionierten Magen-Darm-Passage. Patienten und Methoden: 20 Kinder und Jugendliche im Alter von 9 bis 16 Jahren mit unklaren abdominellen Beschwerden bzw. mit Verdacht auf eine chronisch entzuendliche Darmerkrankung wurden nach einer oralen

  19. Clinical MR at 3 Telsa: Current Status; Klinische MRT bei 3 Tesla: Aktueller Stand

    Energy Technology Data Exchange (ETDEWEB)

    Baudendistel, K.T. [Department of Radiology, College of Medicine, Ohio State University, Columbus (United States); Division of Imaging Research, Department of Radiology, Ohio State University, 1654 Upham Drive, 646, Means Hall, Columbus (United States); Heverhagen, J.T.; Knopp, M.V. [Department of Radiology, College of Medicine, Ohio State University, Columbus (United States)

    2004-01-01

    Clinical MRI is mostly performed at field strengths up to 1.5 Tesla (T). Recently, approved clinical whole-body MR-systems with a field strength of 3 T became available. Its installation base is more rapidly growing than anticipated. While siting requirements and operation of these systems do not differ substantially from systems with lower field strength, there are differences in practical applications. Imaging applications can use the gain in signal-to-noise for increased spatial resolution or gain in speed. This comes at a trade off in increased sensitivity to field inhomogeneities and changes in relaxation times, which lead to changes in image contrast. The benefit of high field for spectroscopy consists in increased signal-to-noise-ratio and improvement in frequency resolution. The increase in energy deposition necessitates the use of special strategies to reduce the specific absorption rate (SAR). This paper summarizes the current state of MR at 3 T. (orig.) [German] Waehrend die klinische MRT zumeist bei Feldstaerken von bis zu 1,5 Tesla (T) durchgefuehrt wird, sind seit juengster Zeit zugelassene klinische 3-T-Ganzkoerper-MR-Systeme verfuegbar. Deren Verbreitung waechst schneller als erwartet. Waehrend sich die Aufstellungsbeduerfnisse und Handhabung dieser Systeme nicht mehr wesentlich von denen mit kleineren Feldstaerken unterscheidet, bestehen jedoch Unterschiede im praktischen Einsatz. Fuer die Bildgebung bei 3 T laesst sich das erhoehte Signal-zu-Rausch-Verhaeltnis (SNR) sowohl zu verbesserter raeumlicher Aufloesung oder schnellerer Bildaufnahme nutzen. Nachteilig fuehrt dies zu einer Erhoehung der Empfindlichkeit auf Feldinhomogenitaeten und veraenderten Relaxationszeiten, die zu Kontrastaenderungen fuehren. Fuer die MR-Spektroskopie liegt der Vorteil in der Erhoehung des SNR und der spektralen Aufloesung. Der Anstieg der pro Hochfrequenzanregung deponierten Energie macht darueber hinaus die Anwendung spezieller Strategien zur Reduktion der

  20. 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

  1. 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

  2. Stress cine MRI for detection of coronary artery disease; Stress-Cine-MRT zur Primaeridagnostik der koronaren Herzkrankheit

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, T.; Hofer, U.; Schild, H. [Bonn Univ. (Germany). Radiologische Klinik; Omran, H. [Medizinische Universitaetsklinik II Bonn (Germany)

    2002-05-01

    mainly be explained by the better image quality with sharp delineation of the endocardial and epicardial borders. Currently, stress MRI is already a realistic clinical alternative for the non-invasive assessment of CAD in patients with impaired image quality in echocardiography. (orig.) [German] Belastungsuntersuchungen sind einer der wesentlichen Pfeiler der nicht-invasiven Diagnostik der koronaren Herzkrankheit (KHK). Die Stress-Cine-Magnetresonanztomographie (Stress-MRT) beruht wie die Stressechokardiographie auf dem direkten Nachweis ischaemieinduzierter Wandbewegungsstoerungen. Ihr Einsatz bei kardialen Belastungsuntersuchungen wurde bisher vor allem durch die langen Untersuchungszeiten und die limitierten Ueberwachungsmoeglichkeiten der Patienten eingeschraenkt. Erst seit kurzem wurden durch technische Weiterentwicklungen (insbesondere ultraschnelle k-Raum-segmentierte Sequenzen) die wesentlichen Rahmenbedingungen fuer eine klinisch praktikable kardiale MRT-Belastungsdiagnostik geschaffen. Als Stress-Induktoren koennen physikalische (Fahrradergometrie) und pharmakologische Belastungsverfahren ({beta}{sub 1}-Mimetika [Dobutamin] oder Vasodilatatoren [Dipyridamol, Adenosin]) eingesetzt werden. Insbesondere seit der Etablierung von Hochdosis-Protokollen mit fakultativer Atropingabe wird die Belastung mit Dobutamin bei der Stress-MRT zum Nachweis einer KHK (Sensitivitaet: 83 - 87%; Spezifitaet: 83 - 86%) von den meisten Arbeitsgruppen favorisiert. Schwerere Komplikationen treten in 0,25% der Faelle auf. Im direkten Vergleich zeigte sich die Dobutamin-Stress-MRT aufgrund der besseren Bildqualitaet der Dobutamin-Stressechokardiographie ueberlegen (Sensitivitaet: 86,2% vs. 74,3%, p < 0,05; Spezifitaet: 85,7% vs. 69,8%, p < 0,05). Die Stress-MRT ist bereits zum jetzigen Zeitpunkt eine realistische - in der Routinediagnostik anwendbare - Alternative zur Stressechokardiographie. Vom Einsatz der Stress-MRT profitieren zur Zeit v.a. Patienten, bei denen aufgrund grundsaetzlich

  3. 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.

  4. 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

  5. Functional MRI of the pelvic floor. Method and references values; Funktionelle MRT des Beckenbodens. Methodik und Referenzwerte

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    Lienemann, A.; Sprenger, D.; Reiser, M. [Klinikum Grosshadern, Muenchen (Germany). Inst. fuer Radiologische Diagnostik; Janssen, U.; Anthuber, C. [Klinikum Grosshadern, Muenchen (Germany). Frauenklinik

    2000-05-01

    Purpose. Functional cine MRI of the pelvic floor is a yet another modality in addition to various radiological fluoroscopic techniques. This article describes our own method in view of the recent literatur and provides morphometric reference values. Material and method. We examined 20 nulliparous women (range of age: 25-51 years) with normal findings in the gynecological and urodynamic examination. Functional cine MRI was performed on a 1.5 Tesla equipment after opacification of the vagina and rectum. We used a T2-weighted gradient-echo sequence (True-FISP) to determine the position of the reference organs at rest and during straining/defecation. Two different reference lines were used. In addition 29 morphometric and functional parameters were measured, all of them being observer independent. Results. Functional cine MRI was able to show the extent and interaction of the pelvic floor organs in all cases with the reference organs always remaining above the pubococcygeal reference line. The depth of the rectocele was 2 cm. With the exception of the diameter of urogenital hiatus the different parts of the levator ani muscle could not be determined. Discussion. Functional cine MRI using an appropiate organ opacification and slice positioning is an objective, unifying diagnostic approach of the pelvic floor. The reference data given can be of help to distinguish normal from abnormal findings. (orig.) [German] Zielsetzung. Die funktionelle MRT des Beckenbodens eroeffnet neue Perspektiven in der Diagnostik. In diesem Beitrag soll die eigene Methodik dargestellt und Referenzwerte bei einem Kollektiv gesunder Nulliparen ermittelt werden. Material und Methode. 20 Nulliparae (Alter 25-51 Jahre) mit unauffaelligem gynaekologischen und urodynamischen Befund. Funktionelle MRT mit Kontrastierung von Scheide und Rektum an einem 1,5-Tesla-System. Mit Hilfe einer T2-gewichteten Gradientenechosequenz (True-FISP) wurden die Veraenderungen der Referenzorgane in Ruhe und waehrend des

  6. MRI of the osteophytosis in experimental osteorthritis of the knee; MRT der Osteophytose bei experimentellen Gonarthrosen

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-11-01

    The value of MRI for the detection of knee osteophytosis was determined in an animal osteoarthritis model. 10 dogs with experimentally induced unilateral osteoarthritis of the knee were investigated with MRI including 2-D-spin echo (SE) and 3-D-gradient echo (GE) imaging. The results were correlated with gross and histopathologic findings and with radiography. Osteophyte formation appeared early in the osteoarthritic process. Pathological analysis yielded 65 osteophytes. With 3-D-GE imaging. 91% of the osteophytes were detected, while 68% were visible on 2-D-SE images. With two-level radiography, 43% of the osteophytes were diagnosed. Additional use of tunnel view and conventional tomography increased the detection rate to 65%. Independent of the imaging technique, MRI revealed three different signal patterns of the osteophyte bone structure. Compared with the histologically evident fat marrow content and the grade of bone sclerosis, best agreement was achieved with 2-D-SE sequences. However, a discrepancy remained in 22%. A fibrocartilaginous layer at the osteophyte surface could be delineated especially on 3-D-GE images. (orig./MG) [Deutsch] Die Wertigkeit der MRT zur Diagnostik der Osteophytose bei Gonarthrosen wurde anhand eines Tiermodells ueberprueft. 10 Hundekniegelenke mit experimentell induzierter Arthrose wurden MR-tomographisch mit 2-D-Spin-echo(SE)- und 3-D-Gradienten-Echo(GE)-Sequenzen untersucht. Die Ergebnisse wurden mit dem makro- und histopathologischen Befund sowie mit der Roentgendiagnostik korreliert. Osteophyten traten bereits fruehzeitig im arthrotischen Krankheitsprozess auf. Die pathologische Auswertung ergab 65 Osteophyten. Hiervon wurden in 3-D-GE-Sequenzen 91% nachgewiesen, gegenueber 68% in 2-D-SE-Sequenzen. Die Nachweisrate betrug bei Roentgenaufnahmen in zwei Ebenen 43%, wobei die zusaetzliche Beruecksichtigung von Tunnelprojekten und konventioneller Tomographie einen Anstieg auf 65% zur Folge hatte. MR-tomographisch liessen sich

  7. MR imaging of the lateral collateral ligaments after ankle sprain; Aussenbandrupturen des Sprunggelenkes - Darstellung mit der MRT vor und nach funktioneller Therapie

    Energy Technology Data Exchange (ETDEWEB)

    Grebe, P. [Klinik fuer Radiologie der Universitaetsklinik, Mainz (Germany); Kreitner, K.F. [Klinik fuer Radiologie der Universitaetsklinik, Mainz (Germany); Roeder, W. [Abt. fuer Chirurgie, St-Hildegardis-Krankenhaus, Mainz (Germany); Kersjes, W. [Klinik fuer Radiologie der Universitaetsklinik, Mainz (Germany); Hennes, R. [Abt. fuer Allgemein- und Unfallchirurgie, St. Josefshospital, Wiesbaden (Germany); Runkel, M. [Unfallchirurgische Klinik der Unversitaetsklinik, Mainz (Germany)

    1995-09-01

    35 patients with ankle sprain were examined by MRI and stress radiographs. 13 were operated afterwards, 22 patients underwent a functional conservative therapy and were examined by MRI and stress radiographs and second time after three months. MRI reports were correct in 12 of 13 operated cases. After conservative therapy we did not find any disrupted ankle ligament. MRI showed intact ligaments thickened by scar. (orig./MG) [Deutsch] 35 Patienten mit klinischem Verdacht auf Aussenbandruptur wurden mit der MRT untersucht. 13 Patienten wurden operiert, 22 konzervativ therapiert. Letztere wurden nach drei Monaten erneut mit MRT und gehaltenen Aufnahmen untersucht. Die MRT-Befunde stimmten in 12 von 13 Faellen mit den operativ erhobenen Befunden ueberein. Nach dreimonatiger konzervativer Therapie waren alle 22 Sprunggelenke stabil. Die rupturierten Baender stellten sich verdickt und durchgaengig dar. (orig./MG)

  8. Infectious spondylitis. A retrospective evaluation of the MRI signs; Die infektioese Spondylitis. Eine retrospektive Auswertung der MRT-Merkmale

    Energy Technology Data Exchange (ETDEWEB)

    Wikstroem, M. [Abt. Roentgendiagnostik, Radiologische Universitaetsklinik und Poliklinik, Univ. Ulm (Germany); Vogel, J. [Abt. Roentgendiagnostik, Radiologische Universitaetsklinik und Poliklinik, Univ. Ulm (Germany); Rilinger, N. [Abt. Roentgendiagnostik, Radiologische Universitaetsklinik und Poliklinik, Univ. Ulm (Germany); Diepers, M. [Rehabilitationskrankenhaus Ulm (Germany). Neurologische Abt.; Hartwig, E. [Abt. fuer Unfallchirurgie, Chirurgische Universitaetsklinik und Poliklinik, Ulm Univ. (Germany); Rieber, A. [Abt. Roentgendiagnostik, Radiologische Universitaetsklinik und Poliklinik, Univ. Ulm (Germany)

    1997-02-01

    Aim and methods: The aim of the present study was to evaluate the MRI criteria of infectious spondylitis (spondylodiscitis). The MR images of 23 patients suffering from spondylodiscitis (78% unspecific, 22% specific) were retrospectively analyzed. Results: The height of the intervertebral discs involved was normal in 40%, reduced in 43% and increased in 17% of the cases. The most common findings can be summarized in an MR triad: (1) The vertebral bodies involved are hypointense in T1-weighted images (100%) with a lack of delineation of the intervertebral discs (53%). (2) The injection of Gd-DTPA yields an enhancement of the vertebral bodies involved and intervertebral discs (95% and 74% respectively). (3) The vertebral bodies and intervertebral discs are hyperintense in T2-weighted sequences (76% and 90% respectively). (orig.) [Deutsch] Um die kernspintomographischen Merkmale der Spondylitis zu ueberpruefen, wurden die MRT-Bilder von 23 Patienten mit einer Spondylitis (78% unspezifisch, 22% spezifisch) retrospektiv analysiert; 40% der befallenen Bandscheiben zeigten eine normale Hoehe, 43% waren verschmaelert und 17% zeigten eine Hoehenzunahme. Die haeufigsten Veraenderungen lassen sich in einer MRT-Trias zusammenfassen: 1. In T1-gewichteten Sequenzen sind die befallenen Wirbelkoerper hypointens (100%) und die Bandscheiben nicht abgrenzbar (53%). 2. Wirbelkoerper und Bandscheiben nehmen Kontrastmittel auf (95 bzw. 74%). 3. Wirbelkoerper und Bandscheiben sind in T2-gewichteten Sequenzen hyperintens (76 bzw. 90%). Dabei stellt sich ein paravertebraler Weichteilbefall in allen Sequenzen isointens zum befallenen Wirbelkoerper dar. Eine Differenzierung zwischen unspezifischer und spezifischer Aetiologie war kernspintomographisch nicht moeglich. (orig.)

  9. 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

  10. 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

  11. 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

  12. 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

  13. Magnetic resonance imaging of meniscal and anterior cruciate ligament injuries of the knee; MRT des Kniegelenkes: Fehleranalyse bezueglich der Meniskus- und Kreuzbanddiagnostik an einem arthroskopisch kontrollierten Patientenkollektiv

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, K.F.; Herrig, A.; Grebe, P. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Runkel, M.; Regentrop, H.J. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Unfallchirurgie

    1998-08-01

    To categorise discrepancies in findings of the menisci and anterior cruciate ligament (ACL) between arthroscopy and MRI. Materials and methods: The MRIs of 236 patients were retrospectively analysed by an experienced radiologist without knowledge of clinical and/for operative findings. Discrepancies in arthroscopic findings were reevaluated together with the arthroscopist to determine their cause of error. Results: The diagnostic accuracies for injuries of the medial and lateral meniscus and the ACL were 92.4%, 92.4%, and 94.1%. respectively. For the menisci, causes for discrepancies in findings (n=31) were: overinterpretation of central signal intensities with contact to the meniscal surface but without disturbance of the meniscal contour as a tear (n=12), insufficient arthroscopie evaluation of the knee joint (n=11), overlooked tears on MR imaging (n=6), misinterpretation of normal anatomic structures (n=1), ``magic angle`` phenomenon (n=1), and missed tears at MRI (n=1). Causes for discrepancies for the ACL (n=18) were: nearly complete versus complete rupture either at MRI or arthroscopy and vice versa (n=9), insufficient arthroscopic evaluation (n=6), insufficient MRI technique (n=2), and overlooked tear on MR imaging (n=1). Conclusions: Discrepant findings between MRI and arthroscopy may be also due to an insufficient arthroscopic evaluation in clinical routine. The close cooperation between surgeons and radiologists improves the understanding of the methods of each other. (orig.) [Deutsch] Evaluation von Befunddiskrepanzen in der Meniskus- und Kreuzbanddiagnostik bei der MRT des Kniegelenkes. Material und Methode: Die MRTs von 236 Patienten wurden retrospektiv in Unkenntnis klinischer und operativer Befunde von einem erfahrenen Untersucher ausgewertet. Anschliessend wurden zur Arthroskopie abweichende Befunde zusammen mit dem Operateur besprochen, um die Ursache der Fehlbefunde im Konsens festzulegen. Ergebnisse: Die MRT erzielte bezueglich der Verletzungen

  14. 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

  15. 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.

  16. 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

  17. 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.)

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

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    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

  19. Determination of left ventricular heart volume by fast MRI in breath-hold technique: how different are quantitative ventricular angiography, quantitative MRI, and visual echocardiography?; Linksventrikulaere Herzvoluminabestimmung mittels schneller MRT in Atemanhaltetechnik: Wie unterschiedlich sind quantitativer Herzkatheter, quantitativer MRT und visuelle Echokardiographie?

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    Rominger, M.B.; Bachmann, G.F. [Giessen Univ. (Germany). Diagnostische Radiologie; Kerckhoff-Klinik GmbH, Bad Nauheim (Germany). Projektgruppe Magnetresonanztomographie; Pabst, W. [Giessen Univ. (Germany). Inst. fuer Medizinische Informatik; Ricken, W.W. [Kerckhoff-Klinik GmbH, Bad Nauheim (Germany). Projektgruppe Magnetresonanztomographie; Dinkel, H.P.; Rau, W.S. [Giessen Univ. (Germany). Diagnostische Radiologie

    2000-01-01

    Goal: Comparison of fast MRI, echocardiography (Echo), and ventricular angiography (Cath) in the assessment of left ventricular global function. Methods: Fast MRI in short axis plane, biplane Cath, and 2D Echo were performed in 62 patients [35 coronary artery diseases, 16 acquired valvular diseases (VD), 9 dilated cardiomyopathies (DCM), 1 congenital heart disease and 1 heart transplantation]. Enddiastolic (EDV), endsystolic (ESV), stroke volumes (SV), cardiac output (CO), and ejection fraction (EF) were compared in MRI and Cath. EF was visually estimated in 2D Echo by an experienced observer. Results: In comparison to MRI, Cath overestimated EF by 8.4%, and Echo underestimated EF by 5.6%. The limits of agreement between MRI and Cath in EF were {+-}23.8%, between MRI and Echo {+-}18%, and between Echo and Cath {+-}19.4%. Significant differences were found between Cath and MRI in EDV, SV, and CO, but not for ESV. The best agreement in EF was found in the group with DCM, the worst in the group with VD. Conclusion: Important systemic and random errors were found in the comparison of MRI, Echo, and Cath. For therapy decision and follow-up, the methods should not be exchanged unscrupulously. (orig.) [German] Ziel: Methodenvergleich von schneller Magnetresonanztomographie (MRT), Echokardiographie (Echo) und Herzkatheter (HK) in der Bestimmung linksventrikulaerer globaler Funktionsparameter. Material und Methoden: Bei 62 Patienten (35 koronare Herzerkrankungen, 16 Herzklappenvitien (KV), 9 idiopathische dilatative Kardiomyopathien (DCM), 1 kongenitale Herzerkrankung und 1 Herzktransplantation) wurde ein Methodenvergleich zwischen schneller Cine MRT im Kurzachsenschnitt, biplanarem HK und 2D Echo durchgefuehrt. Verglichen wurden in MRT und HK linksventrikulaeres enddiastolisches (EDV) und endsystolisches Volumen (ESV), Schlagvolumen (SV), Herzzeitvolumen (HZV) und Ejektionsfraktion (EF). In der Echo wurde die EF visuell durch einen erfahrenen Untersucher bestimmt

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

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    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

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

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    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

  2. 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

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    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

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

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    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

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

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    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

  5. Functional MRI in schizophrenia. Diagnostics and therapy monitoring of cognitive deficits of schizophrenic patients by functional MRI; Funktionelle MRT bei Schizophreniepatienten. Diagnostik und Therapiemonitoring kognitiver Defizite schizophrener Patienten mittels funktioneller MRT

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    Furtner, J.; Prayer, D. [Medizinische Universitaet Wien, Univ.-Klinik fuer Radiodiagnostik, Wien (Austria); Sachs, G. [Medizinische Universitaet Wien, Univ.-Klinik fuer Psychiatrie und Psychotherapie, Wien (Austria)

    2010-02-15

    Cognitive impairments are core psychopathological components of the symptomatic of schizophrenic patients. These dysfunctions are generally related to attention, executive functions and memory. This report provides information on the importance of using functional magnetic resonance imaging (fMRI) for the diagnostics and therapy monitoring of the different subtypes of cognitive dysfunctions. Furthermore, it describes the typical differences in the activation of individual brain regions between schizophrenic patients and healthy control persons. This information should be helpful in identifying the deficit profile of each patient and create an individual therapy plan. (orig.) [German] Kognitive Defizite sind ein zentraler Bestandteil der Symptomatik schizophrener Patienten. Diese Defizite betreffen v. a. die Aufmerksamkeit, exekutive Funktionen sowie das Gedaechtnis. Der vorliegende Beitrag zeigt den Stellenwert der funktionellen Magnetresonanztomographie (fMRT) in Hinblick auf Diagnostik und Therapiemonitoring der unterschiedlichen kognitiven Teilbereiche auf. Darueber hinaus werden die Unterschiede in Bezug auf die Aktivierung der einzelnen Gehirnareale zwischen schizophrenen Patienten und gesunden Kontrollpersonen dargestellt. Diese Informationen sollen helfen, in der Praxis ein Profil der kognitiven Leistungsreduktionen sowie ein darauf angepasstes Therapiekonzept zu erstellen. (orig.)

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

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    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

  7. Imaging cervical myelo- and radiculopathy; Stellenwert von Myelographie, Myelo-CT und MRT in der Diagnostik der zervikalen Radikulo- und Myelopathie

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    Roth, C.; Papanagiotou, P.; Krick, C.; Reith, W.; Grunwald, I.Q. [Universitaetsklinikum des Saarlandes, Homburg (Germany). Abt. Neuroradiologie

    2006-11-15

    This article gives an overview of the diagnostic possibilities available in the diagnosis of cervical myelo- and radiculopathy. We compared conventional myelography, CTM, and MRI. Twenty-five patients with clinical evidence of cervical myelo- or radiculopathy were included. Sagittal and transverse T1-weighted (T1w) TSE and T2-weighted (T2w) TSE sequences were compared with myelography and CTM. Statistical analysis was performed using Wilcoxon's -test. Disc herniation could be depicted in CTM as well as in MRI. The extent of herniation did not differ between CTM and T1w. The extent of herniation seemed higher on T2w than on T1w (p <0.001). Foraminal encroachment was easier to diagnose in CTM. When regarding transverse T1w and T2w images simultaneously, a missing root in MRI corresponded to a missing root in CTM and conventional myelography and vice versa. Our data demonstrated the relative inability of MRI to determine whether the compression is by soft tissue or bony structures. The present study proposes that MRI, when available, should be the imaging method of first choice in patients with suspected radiculo- and myelopathy. (orig.) [German] Diese Arbeit zieht einen Vergleich zwischen zervikaler Myelographie, CT-Myelographie (CTM) und MRT. Es gilt herauszufinden, welchen Stellenwert jede der oben genannten Methoden in Bezug auf Diagnostik und nachfolgende Therapie hat. Bei insgesamt 25 Patienten mit klinischem Verdacht auf eine zervikale Myelo- oder Radikulopathie wurden sowohl eine MRT-Untersuchung der Halswirbelsaeule als auch eine Myelographie durchgefuehrt. Eine Einengung des Spinalkanals liess sich sowohl in der CTM als auch MRT darstellen. Bezueglich des Ausmasses der Spinalkanaleinengung bestand zwischen den T1w-axialen Bildern und den Postmyelo-CT-Bildern kein signifikanter Unterschied. Die MRT ist in der Diagnostik von Myelo- und Radikulopathien der CTM ebenbuertig. Die CT ist zwar in der Differenzierung von weicher und knoecherner Protrusion besser

  8. MRI in definition of bleeding source, lesion pattern and therapy in haemarthros of the knee; Die MRT beim Haemarthros des Kniegelenks: Bestimmung von Blutungsursachen, Verletzungsmustern und Therapie

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    Bachmann, G. [Abt. Diagnostische Radiologie, Klinikum der Justus-Liebig-Universitaet, Giessen (Germany); Juergensen, I. [Orthopaedische Klinik, Klinikum der Justus-Liebig-Universitaet, Giessen (Germany); Leier, S. [Orthopaedische Klinik, Klinikum der Justus-Liebig-Universitaet, Giessen (Germany); Rauber, K. [Abt. Diagnostische Radiologie, Klinikum der Justus-Liebig-Universitaet, Giessen (Germany)

    1996-09-01

    Patients with haemarthros of the knee were examined by MRI and arthroscopy to identify the bleeding source and to determine surgical or conservative therapy. A prospective study was performed on 120 patients who underwent MRI and arthroscopy, point lesions and bleeding sources were documented separately on a standardised form. Arthroscopy demonstrated a ruptured anterior cruciate ligament in 86%, meniscal tears in 55%, disruption of collateral ligaments in 17%, osteochondral lesions in 5% and tears of capsule or plicae in 13%. Disruption of cruciate ligaments caused haemorrhage in all but three cases. In contrast, only meniscal tears located very adjacent to the meniscal basement had bled. Those types of osteochondral lesions caused haemorrhage characterised on MRI by destruction of the subchondral plate and overlying cartilage. Severe lesions of the knee were diagnosed by MRI in 71% to 100%, slight lesions in 13% to 40% of the cases. Single, combined and bland lesions were accurately diagnosed in MRI which permitted a correct prediction of surgical and conservative therapy in 96% and 80%. Morphological criteria in MRI permit identification of bleeding sources in haemarthros of the knee. Different lesion patterns can be separated for the planning of therapy. (orig.) [Deutsch] Bei gesichertem Haemarthros des Knies wurde geprueft, ob mit der MRT Angaben zur Blutungsursache moeglich sind und die relevanten Verletzungsmuster fuer die folgende konservative oder operative Therapie exakt beschrieben werden koennen. In einer prospektiven Studie wurden 120 Patienten mit akutem Haemarthros des Knies nacheinander mit der MRT und der Arthroskopie untersucht. Alle Laesionen und Blutungsquellen wurden getrennt fuer beide Methoden auf standardisierten Erhebungsboegen fuer die Arthroskopie registriert. Arthroskopisch wurden Rupturen der vorderen Kreuzbaender in 86%, Meniskusrisse in 55%, Rupturen der Kollateralbaender in 17%, subchondrale Laesionen in 5% und Kapsel- bzw

  9. MRI in preoperative evaluation of chronic paranasal sinusitis - a comparison with CT; MRT in der praeoperativen Diagnostik der chronischen Sinusitis im Vergleich mit der CT

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    Weiss, F.; Habermann, C.R.; Welger, J.; Steiner, P.; Rozeh, B.; Buecheler, E. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Klinik und Poliklinik fuer Radiologie; Knaape, A.; Metternich, F. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenheilkunde; Schoder, V. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Inst. fuer Mathematik und Datenverarbeitung in der Medizin

    2001-04-01

    Purpose: To determine the value of MRI in the preoperative evaluation of chronic paranasal sinusitis and to compare the results with CT and intraoperative findings. Method/Materials: 42 patients with clinical signs of chronic paranasal sinusitis underwent MRI after CT evaluation on one day, with subsequent functional endoscopic sinus surgery on the next day. Coronary CT was obtained with 5-mm slices and table-feed in the prone position, while MRI was performed in the supine position with coronary T{sub 2}-TSE+pd and coronary and transverse HASTE, each with 5-mm slice thickness. Aquisition time in MRI was less than 8 minutes. Two radiologists reviewed the CT and MRI scans for signs of sinusitis and detection of anatomical landmarks. The results were correlated with the intraoperative findings. Results: MRI offered no artifacts of dental work and showed more often high quality pictures than CT. CT and MRI demonstrated a good correlation in the detection of mucosal pathologies ({kappa}=0.46-0.87) and anatomic variants ({kappa}=0.55-0.86). All important anatomical structures could be evaluated sufficiently with MRI for preoperative management. Both diagnostic tools showed an unsatisfactory correlation with intraoperative findings in the ethmoidal complex and maxillary sinus ({tau}=-0.08-0.3). (orig.) [German] Zielsetzung: Einschaetzung des Stellenwertes der MRT in der Beurteilung der praeoperativen Diagnostik der chronischen Sinusitis und Vergleich mit koronarer CT und intraoperativem Befund. Material und Methodik: 42 Patientinnen mit klinischen Zeichen einer chronischen Sinusitis wurden jeweils innerhalb eines Tages mittels CT und MRT untersucht. Am Folgetag wurde eine transnasale endoskopische Operation an den Nasennebenhoehlen durchgefuehrt. Die CT erfolgte in Bauchlage und koronarer Schichtfuehrung (5 mm Schichtdicke und Tischvorschub). Die MRT wurde an einem 1,5 T-Geraet in Rueckenlage mittels Kopfspule durchgefuehrt. Eingesetzt wurden koronare Protonen-w-, T

  10. 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.)

  11. Functional cine-MRI of the pelvic floor - normal anatomy and pathologic findings; Funktionelle MRT des Beckenbodens: normale Anatomie und pathologische Befunde

    Energy Technology Data Exchange (ETDEWEB)

    Sprenger, D.; Lienemann, A.; Reiser, M. [Klinikum Grosshadern, Muenchen (Germany). Inst. fuer Radiologische Diagnostik; Anthuber, C. [Klinikum Grosshadern, Muenchen (Germany). Frauenklinik

    2000-05-01

    Purpose. Functional MRI of the pelvic floor allows mapping and definition of different forms of pelvic floor dysfunction. Methods. We performed functional MRT of the pelvic floor in 39 healthy nulliparas and 324 patients. The diagnosis of a pathological organ descent was made if certain landmarks of the pelvic floor compartments descended below the pubococcygeal reference-line (PC-line). Results. If there was no organ descent below the PC-line on straining and if the pelvic floor muscles hardly changed position, a normal finding was diagnosed. 70% of organ prolapses came in the combined form. The generally gradual development of an organ descent led to a change of the main finding in 21,6%. The masking of a cystocele (48,6%) or of an enterocele (34,3%) by a rectocele was most frequent in these cases. Discussion. The use of functional MRI of the pelvic floor appears to be especially useful in young patients, in cases of divergent clinical and sonographic or radiological findings and if the presence of a predominant hernial sac with or without enterocele/rectocele is supposed. (orig.) [German] Ziel. Die funktionelle MRT des Beckenbodens ermoeglicht die Dokumentation und Definition der verschiedenen Manifestationsformen einer Beckenbodeninsuffizienz. Methodik. Es wurde bei 39 gesunden Nulliparen und 324 Patientinnen eine funktionelle MRT des Beckenbodens durchgefuehrt. Ein pathologischer Organdeszensus wurde dokumentiert, wenn bestimmte Kennstrukturen der Beckenbodenkompartimente unterhalb der pubokokygealen Referenzlinie (PC-Linie) zu liegen kamen. Ergebnisse. Beim Normalbefund zeigt sich unter Pressen kein Deszensus der Kennstrukturen unterhalb der PC-Linie und die Beckenbodenmuskulatur veraendert ihre Position kaum. In 70% fand sich die kombinierte Form eines Organdeszensus. Die meist stufenweise Entwicklung eines Organvorfalles fuehrte bei 21.6% zu einem Wechsel des Hauptbefundes. Am haeufigsten war hierbei die Maskierung einer Zystozele (48,6%) oder einer

  12. 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

  13. 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.)

  14. 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

  15. Comparison of noninvasive MRT-procedures for the temperature measurement for the application during medical thermal therapies; Vergleich nichtinvasiver MRT-Verfahren zur Temperaturmessung fuer den Einsatz bei medizinischen Thermotherapien

    Energy Technology Data Exchange (ETDEWEB)

    Rademaker, G.; Jenne, J.W.; Rastert, R.; Roeder, D.; Schad, L.R. [Deutsches Krebsforschungszentrum (DKFZ), Abt. Biophysik und Medizinische Strahlenphysik, Heidelberg (Germany)

    2003-07-01

    Novel methods for hyperthermia tumor therapy, such as high-intensity focused ultrasound (HIFU) or laser-induced thermotherapy (LITT), require accurate non-invasive temperature monitoring. Non-invasive temperature measurement using magnetic resonance imaging (MRI) is based on the analysis of changes in longitudinal relaxation time (T1), diffusion coefficient (D), or water proton resonance frequency (PRF). The purpose of this study was the development and comparative analysis of the three different approaches of MRI temperature monitoring (T1, D, and PRF). Measurements in phantoms (e.g., ultrasound gel) resulted in the following percent changes: T1-relaxation time: 1.98%/ C; diffusion coefficient: 2.22%/ C; and PRF: -0,0101 ppm/ C. All measurements were in good agreement with the literature. Temperature resolutions could also be measured from the inverse correlation of the data over the whole calibration range: T1: 2.1{+-}0.6 C; D: 0.93{+-}0.2 C; and PRF: 1.4{+-}0.3 C. The diffusion and PRF methods were not applicable in fatty tissue. The use of the diffusion method was restricted due to prolonged echo time and anisotropic diffusion in tissue. Initial tests with rabbit muscle tissue in vivo indicated that MR thermometry via T1 and PRF procedures is feasible to monitor the local heating process induced by HIFU. The ultrasound applicators in the MR scanner did not substantially interfere with image quality. (orig.) [German] Neue Hyperthermieverfahren zur Tumortherapie basieren auf hochenergetischem fokussiertem ultraschall (HIFU) oder laserinduzierter thermotherapie (LITT). Fuer diese Verfahren ist eine genaue nichtinvasive Temperaturkontrolle erforderlich. Die nichtinvasiven Temperaturdarstellungen mit der magnetresonanztomographie (MRT) basieren auf Aenderung der longitudinalen Relaxationszeit (T{sub 1}), des diffusionskoeffizienten (D) oder der protonenresonanzfrequenz (PRF). Das Ziel waren die Entwicklung und der Vergleich der drei unterschiedlichen Methoden (T

  16. Cryotherapy of malignant tumors: MR imaging in comparison with pathological changes in mice; Kryotherapie maligner Tumoren: Untersuchungen mittels MRT im Tierexperiment und Vergleich mit morphologischen Veraenderungen

    Energy Technology Data Exchange (ETDEWEB)

    Romaneehsen, B.; Anders, M.; Roehrl, B.; Hast, H.J.; Schiffer, I.; Neugebauer, B.; Teichmann, E.; Schreiber, W.G.; Thelen, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Hengstler, J.G. [Mainz Univ. (Germany). Inst. fuer Toxikologie

    2001-07-01

    Aim of our study was to investigate the efficacy of 7 F cryoprobes for percutaneous use morpho- and histologically, to examine the role of apoptosis after cryotherapy, and to compare contrast-enhanced MRI with histopathological findings at different time intervals in a tumor-mouse model. Methods: Percutaneous cryotherapy was performed in 15 immunocompromised nude mice with subcutaneously implanted tumors using the non-small-cell lung cancer cell line Lu 1. In group a) 7 mice were sacrificed after definite time intervals and histological examinations were done for evaluation of necrosis and apoptosis (HE; TUNEL assay); 2 mice are in long-term follow-up. In group b) in 6 mice tumor destruction and perfusion before and after freezing were investigated with native and contrast-enhanced MR imaging (T{sub 1}- and T{sub 2}-weighted spin-echo) and compared with histopathological findings. Histological control were done in 2 untreated mice. Results: We observed fast tumor-reduction within two weeks (ca. 50%). On long-term follow-up (> 6 months) no recurrence has been noticed so far. Tumors were well vascularized prior to treatment and did not-show contrast enhancement an any time after cryotherapy. A narrow contrast-enhanced zone was seen on the tumor border subcutaneously as a sign of peripheral hyperemia and central vascular stasis after cryotherapy. On histology there was evidence of both apoptosis and necrosis. (orig.) [German] Evaluierung der Durchfuehrbarkeit und Effizienz einer perkutanen Kryotherapie mittels 7-F-Kryosonde in Nacktmaeusen. Erheben des histopathologischen Befundes der Kryolaesion nach definierten Zeitintervallen und Ueberpruefung einer moeglichen Rolle der Apoptose nach Kryotherapie. Darstellung morphologischer Veraenderungen des Tumors und des angrenzenden Gewebes im Anschluss an die Kryotherapie mittels kontrastmittelunterstuetzter MRT. Methodik: Zweiminuetige Kryotherapie subkutan implantierter Tumoren eines nicht-kleinzelligen Bronchialkarzinoms

  17. Functional MRI of the pelvic floor: postpartum changes of primiparous women after spontaneous vaginal delivery; Funktionelle Magnetresonanztomographie (MRT) des Beckenbodens: Postpartale Veraenderungen bei Erstgebaerenden nach vaginaler Spontangeburt

    Energy Technology Data Exchange (ETDEWEB)

    Lienemann, A.; Fischer, T.; Reiser, M. [Inst. fuer Klinische Radiologie, Klinikum der Univ. Muenchen (Germany); Anthuber, C. [Klinik und Poliklinik fuer Geburtshilfe und Frauenheilkunde, Klinikum der Univ. Muenchen/Grosshadern (Germany)

    2003-08-01

    Purpose: Detection of morphological and functional changes of the pelvic floor with functional MRI in primiparous women after spontaneous vaginal delivery. Methods and Materials: The study comprises 26 primiparous women after vaginal delivery and a control group of 41 healthy asymptomatic nulliparous volunteers. MRI was performed on a 1.5 T system in supine position with vagina and rectum opacified with Sonogel. The static images consisted of sagittal and axial T{sub 2}-weighted SE sequences and functional images of true FISP sequences in midsagittal and axial planes acquired with the patient at rest, straining and during defecation. Evaluation of morphometric parameters included pelvimetry, thickness of the puborectal muscle and width of the urogenital hiatus as well as position and movement of the pelvic organs relative to the pubococcygeal reference line. Results: The configuration of the bony pelvis did not differ for both groups. The puborectal muscle was significantly thinner in the study group (0.8 cm vs 0.6 cm). The functional images showed no significant differences between both groups at rest but a significantly increased incidence in the descent of the bladder neck, vaginal fornix and anorectal junction in the study group during straining. In addition, the primiparous women had more prominent rectoceles (0.6 cm vs 1.5 cm). Conclusion: Static imaging alone fails to demonstrate relevant pelvic floor changes and a functional method is necessary to evaluate the interactions of the pelvic organs regarding organ descent. Functional MRI of the pelvic floor is an excellent method to reveal the significant changes of the pelvic floor after vaginal birth without exposing the uterus to radiation. (orig.) [German] Ziel: Darstellung von morphologischen und funktionellen Veraenderungen am Beckenboden bei Erstgebaerenden nach spontanvaginaler Entbindung mittels funktioneller MRT. Methodik: Funktionelle MRT des Beckenbodens von 26 Erstgebaerenden nach vaginaler

  18. Laser-induced thermotherapy for liver metastases in an open 0.2 T MR system; Laserinduzierte Thermotherapie (LITT) von Lebermetastasen in einem offenen 0,2 T MRT

    Energy Technology Data Exchange (ETDEWEB)

    Reither, K.; Wacker, F.; Wolf, K.J. [Freie Univ. Berlin (Germany). Abt. fuer Radiologie und Nuklearmedizin; Ritz, J.P.; Isbert, C.; Germer, C.T. [Freie Univ. Berlin (Germany). Chirurgische Klinik 1 fuer Visceral-, Gefaess- und Thoraxchirurgie; Roggan, A. [Freie Univ. Berlin (Germany). Inst. fuer Medizinische Physik und Lasermedizin; Wendt, M. [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Radiology

    2000-02-01

    Objective: To test the feasibility and safety of the laser-induced thermotherapy (LITT) for liver metastases in open MR imaging system operating at 0.2 Tesla. Method: Laser therapy using the Nd:YAG laser was performed on 25 patients with a total of 41 liver metastases. An open low-field MRI scanner was used for puncture, positioning of the laser applicator, and monitoring the therapy. A true FISP sequence was used to track the puncture in close to real-time. Localization diagnostics and temperature monitoring were aided by T{sub 1}-weighted gradient echo sequences in the breath-holding technique. In the first follow up after 24-48 hours, a contrast-enhanced T{sub 1}-weighted gradient-echo sequence was performed in an MRI scanner at 1.5 T. The pre-, intra- and post-interventional volumes of the liver metastases as well as the thermolesions and the thermonecroses were determined. Results: LITT in an open MRI system was technically feasible in all patients with no clinically relevant complications. The mean volumes of the thermolesions measured during intervention in low-field MRI were lower than the volumes of the thermonecroses measured after intervention in high-field MRI. Conclusion: The technique presented here of laser-induced thermotherapy for liver metastases in an open MRI system is technically feasible and safe. (orig.) [German] Ziel: Untersuchung der Praktikabilitaet und Sicherheit der laserinduzierten Thermotherapie (LITT) von Lebermetastasen in einem offenen 0,2 T MRT. Methode: Es wurde eine Lasertherapie mit einem Nd:YAG-Laser bei 25 Patienten mit insgesamt 41 Lebermetastasen durchgefuehrt. Punktion, Plazierung des Laserapplikators und Therapiekontrolle erfolgten in einem offenen Niederfeld-MRT. Zur echtzeitnahen Punktionskontrolle wurde eine True-FISP-Sequenz verwendet. Die Lokalisationsdiagnostik und das Thermomonitoring erfolgte mit Hilfe T{sub 1}-gewichteter Gradienten-Echo-Sequenzen in Atemanhaltetechnik. Zur ersten Verlaufskontrolle wurde nach 24

  19. In-vitro examinations and patient examinations by MR: Significance of metal implants. In-vitro- und Patientenuntersuchungen mittels MRT: Bedeutung metallischer Implantate

    Energy Technology Data Exchange (ETDEWEB)

    Grebmeier, J.; Roedl, W. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Zentrum Innere Medizin); Weikl, A. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Medizinische Klinik 2 mit Poliklinik); Glueckert, K. (Waldkrankenhaus St. Marien, Erlangen (Germany, F.R.). Orthopaedische Klinik mit Poliklinik); Hofmann-Preiss, K. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Chirurgische Klinik mit Poliklinik); Huk, W.J. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Kopfklinikum); Wolf, F. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Inst. und Poliklinik fuer Nuklearmedizin)

    1991-05-01

    This study presents the results of in-vitro and clinical experiences with metallic implants during MRT investigations. In-vitro temperature measurements of various implants showed little temperature rise depending on the shape and the orientation in the static magnetic field (max. 0.3deg C). Ferromagnetic forces could not be detected with these implants. In contrast, severe temperature increase (9.3deg C) was observed with an intratracheal spiral tube. Tubes of this type should not be used in MR imaging to avoid the risk of burning. 105 MR examinations were performed in patients with metallic implants (CNS shunts, aortocoronary bypass grafts, aortic-, mitral-prothesis, orthopedic implants, skin staples, shrapnels). Patients with vascular clips were accepted for MR imaging when the clips were non-ferromagnetic only. No adverse effects were observed in these patients. (orig.).

  20. How safe is magnetic resonance imaging in patients with contraceptive implants; Wie sicher ist die MRT bei Patientinnen mit kontrazeptiven Implantaten

    Energy Technology Data Exchange (ETDEWEB)

    Muehler, M.; Taupitz, M. [Charite - Universitaetsmedizin Berlin (Germany). Institut fuer Radiologie

    2006-07-15

    When patients with an implanted contraceptive device undergo MRI, it must be ensured that the examination involves no risk to the patient (MR safety) and that the diagnosis is not affected by artifacts or the function of the device compromised (MR compatibility). Two basic types of intrauterine devices can be distinguished: the metal-containing/metal-free intrauterine device (IUD) and the hormone-containing implant, the fully metal-free intrauterine system (IUS), as well as the ESSURE insert made of stainless steel, which has been approved for use in Europe since February 2001. The metal-containing and metal-free IUDs and ESSURE are MRI compatible up to a magnetic field strength of 1.5 T. They do not interact in any relevant way with the external magnetic or high-frequency field and the temperature increase is within the physiologic range. The implants merely produce a local signal void with a shape that depends on their orientation relative to the magnetic field lines. At 3 T, only the metal-free IUD and the IUS are MRI safe in terms of the material used. In contrast, metal-containing IUDs and the ESSURE have not yet been fully evaluated in the 3 T field, which is why they represent a contraindication to MRI. No data are available on the MRI compatibility at 3 T for any of these devices. (orig.) [German] Bei der Untersuchung von Patientinnen mit kontrazeptiven Implantaten im MRT muss gewaehrleistet sein, dass es weder zu einer Gesundheitsgefaehrdung der Patientin (MR-Sicherheit) noch zu befundrelevanten Artefakten oder einer Funktionsbeeintraechtigung des Implantats (MR-Kompatibilitaet) kommt. Unterschieden werden im wesentlichen 2 Systeme kontrazeptiver Implantate: Das metallhaltige/-lose Intrauterinpessar (IUP; engl. intrauterine device, IUD) sowie das bauaehnliche, hormontragende, vollstaendig metallfreie intrauterine System (IUS; engl. intrauterine system) und das seit Februar 2001 auf dem europaeischen Markt zugelassene, aus Edelstahl gefertigte ESSURE. Die

  1. 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

  2. Hydro-MRI in inflammatory bowel diseases: a comparison with colonoscopy and histopathology; Hydro-MRT bei entzuendlichen Darmerkrankungen - Eine koloskopisch-histologische Vergleichsstudie

    Energy Technology Data Exchange (ETDEWEB)

    Schunk, K.; Reiter, S.; Kern, A. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Orth, T.; Wanitschke, R. [Mainz Univ. (Germany). Medizinische Klinik und Poliklinik

    2001-08-01

    Purpose: To compare hydro-MRI with colonoscopy and biopsy specimen regarding the assessment of inflammatory activity and the differentiation of inflammatory bowel diseases. Material and methods: After an oral bowel opacification using 1000 ml of a 2.5% mannitol solution and a rectal bowel opacification using 250-500 ml of a 0.9% saline solution, axial and coronal breath-hold sequences {+-}Gd-DTPA (HASTE-['half-Fourier acquisition single-shot turbo spin echo'] and dynamic FLASH-['fast low angle shot']) were acquired in 27 patients with inflammatory bowel disease. The enhancement of the bowel wall as well as morphological MRI findings were correlated with colonoscopy and biopsy specimens. By means of the MRI findings, Crohn's disease (CD) and ulcerative colitis (UC) should be differentiated. Results: In CD, a significant correlation between the contrast enhancement of the inflamed bowel wall ({delta} SI) and the endoscopic/histopathologic indices could be established (r=0.52; p=0.02 and r=0.72; p=0.001). In UC, no correlations between {delta} SI and the endoscopic/histopathologic indices could be found. The correct diagnosis of CD and UC by MRI findings was possible in 22/27 patients (81%). Conclusion: Hydro-MRI with dynamic studies is suitable for the assessment of disease activity in CD, but unreliable in UC. Hydro-MRI provides useful information for the differentiation of CD and UC. (orig.) [German] Zielsetzung: Vergleich der Hydro-MRT mi Koloskopie und Histopathologie bezueglich der Beurteilung der entzuendlichen Aktivitaet und der Differenzierung entzuendlicher Darmerkrankungen. Patienten und Methodik: Bei 27 Patienten mit einer entzuendlichen Darmerkrankung wurden nach einer oralen Darmkontrastierung mit 1000 ml einer 2,5%igen Mannitolloesung und einer rektalen Darmkontrastierung mit 250-500 ml einer 0,9%igen NaCl-Loesung atemangehaltene transversale und koronare Sequenzen {+-} intravenoese Gd-DTPA-Applikation (HASTE

  3. 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.)

  4. 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

  5. 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

  6. Functional MRI of the pharynx in obstructive sleep apnea (OSA) with rapid 2-D flash sequences; Funktionelle MRT des Pharynx bei obstruktiver Schlafapnoe (OSA) mit schnellen 2D-FLASH-Sequenzen

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, L. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Guenther, E. [Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Gauger, J. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Nitz, W. [Siemens Medizintechnik, Erlangen (Germany); Kastenbauer, E. [Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Reiser, M. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany)

    1996-03-01

    Functional imaging of the pharynx used to be the domain of cineradiography, CT and ultrafast CT. The development of modern MRI techniques led to new access to functional disorders of the pharynx. The aim of this study was to implement a new MRI technique to examine oropharyngeal obstructive mechanisms in patients with obstructive sleep apnea (OSA). Sixteen patients suffering from OSA and 6 healthy volunteers were examined on a 1.5 T whole-body imager (`Vision`, Siemens, Erlangen Medical Engineering, Germany) using a circular polarized head coil. Imaging was performed with 2D flash sequences in midsagittal and axial planes. Patients and volunteers were asked to breathe normally through the nose and to simulate snoring and the Mueller maneuver during magnetic resonance imaging (MRI). Prior to MRI, all patients underwent an ear, nose and throat (ENT) examination, functional fiberoptic nasopharyngoscopy and polysomnography. A temporal resolution of 6 images/s and an in-plane resolution of 2.67x1.8 mm were achieved. The mobility of the tongue, soft palate and pharyngeal surface could be clearly delineated. The MRI findings correlated well with the clinical examinations. We propose ultrafast MRI as a reliable and non-invasive method of evaluating pharyngeal obstruction and their levels. (orig.) [Deutsch] Die funktionelle Bildgebung des Pharynx war bisher eine Domaene der Hochfrequenzroentgenkinematographie, der Computertomographie (CT) und der ultraschnellen Computertomographie. Die Entwicklung moderner Techniken in der Magnetresonanztomographie (MRT) fuehrte zu neuen Ansaetzen in der Diagnostik pharyngealer Dysfunktionen. Ziel der vorliegenden Studie war die Implementierung neuer schneller MR-Sequenzen, um Verschlussmechanismen entlang des Pharnyxschlauches bei Patienten mit obstruktiver Schlafapnoe (OSA) zu untersuchen. 16 Patienten mit OSA und 6 gesunde Probanden wurden an einem 1,5-T-Ganzkoerpermagnetresonanztomographen (`Vision`, Siemens Medizintechnik, Erlangen

  7. 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

  8. 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

  9. MRI of the cerebellopontine angle in patients with cleido-cranial dysostosis; MRT der Kleinhirnbrueckenwinkelregion bei Patienten mit Dysostosis cleido-cranialis

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, A.; Engelbrecht, V.; Nawatny, J.; Moedder, U. [Duesseldorf Univ. (Germany). Inst. fuer Diagnostische Radiologie; Messing-Juenger, M. [Duesseldorf Univ. (Germany). Neurochirurgische Klinik; Reifenberger, G. [Duesseldorf Univ. (Germany). Inst. fuer Neuropathologie

    2001-04-01

    Purpose: Cleidocranial dysostosis (CCD) is an autosomal dominant bone disorder in which deafness is common secondary to malformation of the middle ear structures. The study aimed at MRI evaluation of the cerebellopontine angle in 7 patients with a history of CCD - two generation spanned relatives. Material and methods: Cranial MRI in 7 patients with CCD (4 women/3 men aged between 8 and 46 years) was performed. In two patients hearing disorders were present. The examinations encompassed multi-planar spinecho sequences of the cerebellopontine angle in 3-mm slice thickness before and after administration of contrast medium. Results: The clinically most conspicuous female patient (hearing loss, ataxia, headache) showed a strongly contrast-enhancing tumor in MRI that was histologically proved to be an acoustic schwannoma. Concerning the other family members, no pathological findings were noted except for non-pneumatized mastoids. Conclusion: The first report of a patient with CCD and an acoustic schwannoma shows that in case of hearing loss in these patients also a retrocochlear cause must be considered. (orig.) [German] Ziel: Die Dysostosis cleido-cranialis (DCC) ist eine autosomal-dominant erbliche Knochenerkrankung, bei der aufgrund von Mittelohrmissbildungen gehaeuft Hoerstoerungen beobachtet werden. Wir ueberpruefen bei 7 von diesem Syndrom betroffenen Verwandten 1. und 2. Grades, ob sich kernspintomographisch Auffaelligkeiten der Kleinhirnbrueckenwinkelregion nachweisen lassen. Material und Methoden: MRT-Untersuchungen des Schaedels bei 7 Patienten mit DCC (4 Frauen, 3 Maenner im Alter zwischen 8 und 46 Jahren). Bei zwei Patienten lagen klinisch Hoerstoerungen vor. Die Bildgebung umfasste multiplanare Spin-Echo-Sequenzen und wurde im Bereich des Kleinhirnbrueckenwinkels in 3 mm Schichtdicke vor und nach Gadoliniumgabe durchgefuehrt. Ergebnisse: Die klinisch auffaelligste Patientin (progredienter Hoerverlust, Ataxie, Cephalgien) zeigte in der MRT einen kraeftig

  10. 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

  11. 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

  12. 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)

  13. 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.)

  14. 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

  15. MRI in Crohns disease after transduodenal contrast administration using negative oral MRI constrast media; MRT-Diagnostik des Morbus Crohn nach transduodenaler Fuellung mit negativem oralem MR-Kontrastmittel

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    Holzknecht, N.; Helmberger, T.; Herrmann, K.; Reiser, M. [Institut fuer Klinische Radiologie, Ludwig-Maximilians-Universitaet Muenchen (Germany); Ochsenkuehn, T.; Goeke, B. [Medizinische Klinik II, Ludwig-Maximilians-Universitaet Muenchen (Germany)

    2003-01-01

    To compare the efficacy and quality of conventional and MR enteroclysis with different filling methods regarding the assessment of extension and extraluminal manifestations in Crohn's disease.Material and Methods 190 patients with known Crohn's disease were studied following small bowel enteroclysis, after oral administration or direct transduodenal filling in the MRI-department.T1- and T2-weighted breathhold MRI-scans w/o spectral fat suppression w/o i.v.Gd-DTPA were applied using negative oral superparamagnetic contrast media. Typical findings were marked bowel wall thickening with laminated wall contrast enhancement.In 135 patients 98,2% of affected bowel segments, 97,5% of stenoses and all 16 fistulas were detected,when conventional enteroclysis was employed as standard of reference.Additional important extraluminal findings such as ileoileal (n = 18), ileosigmoidal adhesions (n = 12), extraluminal abscesses (n = 35) and pseudotumors (n = 8) were visualized in 73/135 patients. Concerning the distension of jejunum and ileum, oral filling was rated significantly inferior to transduodenal filling in all small bowel segments,whereas filling in the MRI-unit was rated superior to fluoroscopic, mostly due to a mean transport time of 20 min to the MRI-unit. No clinically important findings of enteroclysis were missed when using MRI. Therefore, in patients with Crohn's disease, conventional enteroclysis can be replaced by MRI.For optimal bowel distension oral contrast administration is inferior to transduodenal filling, if a larger time delay between filling and the MRI-scan can be avoided. (orig.) [German] Zielsetzung Vergleich der diagnostischen Effizienz und Qualitaet von konventionellem und MRT-Enteroklysma mit unterschiedlichen Fuellungsmethoden und negativem oralem KM bzgl.Ausdehnung und relevanter Zusatzinformationen bei Morbus Crohn.Material und Methoden 190 Patienten mit bekanntem Morbus Crohn wurden teils nach Enteroklysma, oraler KM-Gabe, oder

  16. Magnetic resonance imaging for the assessment of myocardial perfusion. Value of various semiquantitative perfusion parameters; MRT zur Beurteilung der Myokardperfusion. Aussagekraft verschiedener semiquantitativer Perfusionsparameter

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    Huber, Armin; Schweyer, M.; Bauner, K.; Theisen, D.; Rist, C.; Schoenberg, S.; Reiser, M. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Klinische Radiologie, Muenchen (Germany); Muehling, O.; Naebauer, M. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen, Medizinische Klinik I, Muenchen (Germany)

    2007-04-15

    The aim of this study was to determine the diagnostic accuracy of various semiquantitative perfusion parameters of the magnetic resonance perfusion examination of the myocardium compared to conventional coronary angiography. Twenty patients with suspicion of coronary artery disease who underwent coronary angiography were examined by MR imaging within 14 days before or after coronary angiography. A perfusion examination during adenosine application (140 {mu}g/kg/min) and at rest was performed using a saturation recovery turboFLASH sequence. The semi-quantitative parameters maximum signal intensity (SIM), time-to-peak (TTP), area under the curve (AUC) and upslope (US) were determined using dedicated software (Dynamic Signal Analysis, ARGUS, Siemens Medical Solutions) for the evaluation of the signal-intensity-time curves. In addition, the ratio of these parameters (MPRI: myocardial perfusion reserve index) were determined by dividing the values of the stress examination by the values of the rest examination. Accuracy was 78.4% (SIM), 64.9% (TTP), 64.2% (AUC) and 70.4% (US) for the evaluation of the stress examination. Accuracy for the MPRI of the semi-quantitative parameters was 72.2% (SIM), 50.9% (TTP), 72.2% (AUC) und 89.1% (US). A combined semi-quantitative evaluation of the MPRI values using the ratio of the upslope values of the stress and rest examination was shown to be the most accurate method. MPRI (US{sub Stress}/US{sub Rest}) is superior to an evaluation of the stress examination alone. (orig.) [German] Ziel der Studie war es, die diagnostische Aussagekraft verschiedener semiquantitativer Parameter der MRT-gestuetzten Perfusionsuntersuchung des Myokards im Vergleich zur Herzkatheteruntersuchung zu bestimmen. Zwanzig Patienten mit Verdacht auf koronare Herzerkrankung, bei denen eine Herzkatheteruntersuchung erfolgt war, wurden innerhalb von 14 Tagen vor oder nach der Katheteruntersuchung im MRT untersucht. Es wurde eine Perfusionsuntersuchung waehrend

  17. 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

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    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

  18. MRI assisted thermometry for regional hyperthermia and interstitial laser thermotherapy; MRT-gestuetzte Thermometrie in der regionalen Tiefenhyperthermie und interstitiellen Laserthermotherapie

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    Peller, M.; Reinl, H.; Reiser, M.F. [Inst. fuer Klinische Radiologie, Klinikum Grosshadern der Ludwig-Maximilians-Univ. Muenchen (Germany); Muacevic, A. [Neurochirurgische Klinik und Poliklinik, Klinikum der Ludwig-Maximilians-Univ. Muenchen (Germany); Sroka, R. [Laserforschungslabor der Urologischen Klinik, Klinikum der Ludwig-Maximilians-Univ. Muenchen (Germany); Abdel-Rahman, S.; Issels, R. [Inst. fuer Molekulare Immunologie, GSF-Forschungszentrum fuer Umwelt und Gesundheit Neuherberg, Muenchen (Germany); Medizinische Klinik, III, Klinikum der Ludwig-Maximilians Univ. Muenchen (Germany)

    2004-04-01

    Purpose. To demonstrate the potential of quantitative MRI-assisted thermometry for the treatment of tumor patients with regional hyperthermia (RHT) and interstitial laser thermotherapy (ILTT). Methods. Two patients and seven tissue samples were investigated using theT1-relaxation time and the chemical shift of the proton resonance frequency (PRF) as temperature sensitive MRI-parameters at 0.2 and 1.5 T. Thermotherapy was applied using either a dedicated MRI-hyperthermia hybrid system or a temperature controlled laser with 830 nm. Results. Both patients were treated successfully showing clinical benefit. T1 and PRF are depending on the applied thermotherapy method and on the MR-system suitable for MRI-assisted thermometry. The clinical application based on phantom results is not necessarily adequate. (orig.) [German] Fragestellung. Die Untersuchungen zeigen die Moeglichkeiten einer quantitativen MR-getuetzten Thermometrie bei der Behandlung von Tumorpatienten mit regionaler Tiefenhyperthermie (RHT) und interstitieller Laserthermotherapie (ILTT). Methodik. Bei 2 Tumorpatienten und 7 Gewebeproben wurden die chemische Verschiebung der Protonenresonanzfrequenz und die T1-Relaxationszeit als temperaturempfindliche MR-Parameter bei 0,2 bzw. 1,5 T untersucht. Die Thermotherapie erfolgte dabei mit einem speziellen MRT-Hyperthermie-Hybridsystem (RHT) bzw. einem temperaturgesteuerten Diodenlaser bei 830 nm (ILTT). Ergebnisse. Beide Patienten konnten klinisch erfolgreich behandelt werden. Die gewaehlten temperatursensitiven MR-Parameter sind, abhaengig vom therapeutischen Ansatz und den Eigenschaften des jeweiligen MR-Systems, fuer eine klinische MR-gestuetzte Thermometrie geeignet. Eine direkte Uebertragung der Ergebnisse aus Phantommessungen ist nicht ohne Einschraenkung moeglich. (orig.)

  19. 3D CISS, 3D MP-PAGE and 2D TSE for MRI prior to Cochlear implantation; 3D CISS, 3D MP-RAGE und 2D TSE fuer die praeoperative MRT vor Cochlea Implant

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    Seitz, J.; Held, P.; Voelk, M.; Lenhart, M.; Strotzer, M. [Klinikum der Univ. Regensburg (Germany). Inst. fuer Roentgendiagnostik; Waldeck, A. [Klinikum der Univ. Regensburg (Germany). Klinik und Poliklinik fuer Hals-Nasen-Ohrenheilkunde

    2000-03-01

    Purpose: The aim of this study was to determine the presurgical predictive value of high resolution MRI in patients scheduled for chochlear implantation. Method and material: The presurgical MRI (3D CISS, 3D MP-RAGE with and without i.v. contrast medium, 2D TSE) findings of 54 patients and the intraoperative situation reported by the surgeon were compared retrospectively. The surgical and functional success of the cochlear implantation was evaluated. Results: We found a high degree of correlation between MRI and intraoperative findings concerning the patency of the whole cochlea and anomalies as well as in the diagnosis of pathology of the cochlear, vestibular and facial nerves and in anomalies of the internal auditory canal. However, in four out of 54 patients there was a false negative prediction regarding the patency of the cochlea. The sensitivity was 50% (4/8), the specificity 100% (46/46). Concerning the surgical success the accuracy was 100%. In all patients MRI gave sufficient anatomical information to the surgeon concerning the jugular bulb and the facial nerve. Conclusion: A high-resolution MRI protocol consisting of coronal 2D T2w TSE, 3D T2*w transverse CISS; plain and contrast enhanced sagittal T1w 3D MP-RAGE is recommended for the evaluation of candidates scheduled for cochlear implantation. (orig.) [German] Ziel: Das Ziel dieser Studie war, den praeoperativen Vorhersagewert der hochaufloesenden MRT bei Patienten, welche fuer ein Cochlea Implant vorgesehen sind, zu ermitteln. Material und Methode: Die praeoperativen Befunde der MRT (3D CISS, 3D MP-RAGE vor und nach i.v. Gabe von Gadolinium, 2D TSE) von 54 Patienten und die vom Operateur vorgefundenen intraoperativen Verhaeltnisse wurden verglichen. Sowohl der chirurgische Erfolg der Implantation als auch die Funktion des Cochlea Implants wurden evaluiert. Ergebnisse: Es zeigte sich eine hohe Uebereinstimmung der MRT-Befunde sowie der intraoperativ vorgefundenen Situation bezueglich der Offenheit der

  20. Magnetic resonance imaging of hypertrophic cardiomyopathy. Evaluation of diastolic function; MRT-Bildgebung bei hypertropher Kardiomyopathie (HCM). Evaluation der diastolischen Funktion

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    Schwarz, F.; 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); Schwab, F. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Josef Lissner Laboratory for Biomedical Imaging, Institut fuer Klinische Radiologie, Muenchen (Germany); Beckmann, B.M.; Schuessler, F.; Kaeaeb, S. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Medizinische Klinik und Poliklinik I, Muenchen (Germany); Zinsser, D.; Goelz, T. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany)

    2013-01-15

    Hypertrophic cardiomyopathy (HCM) has a prevalence of approximately 0.2% and is clinically asymptomatic in many patients or presents with unspecific symptoms. This explains the importance of imaging for the diagnosis of HCM as well as for the assessment of the clinical course. The definitive finding in HCM is myocardial hypertrophy with thickening of the ventricular wall {>=} 15 mm. While echocardiography is an excellent screening tool magnetic resonance imaging (MRI) allows a comprehensive analysis of the heart in HCM. This includes a detailed analysis of the distribution and extent of myocardial hypertrophy, a thorough evaluation of systolic and diastolic cardiac function, the assessment of the presence and extent of dynamic outflow tract obstruction as well as the description of the systolic anterior motion (SAM) phenomenon of the mitral valve with secondary mitral insufficiency. When contrast material is administered, additional information about myocardial perfusion as well as the presence and extent of myocardial fibrosis can be obtained. This study compared systolic functional parameters as well as end systolic and end diastolic wall thickness of patients with and without diastolic dysfunction. (orig.) [German] Die hypertrophe Kardiomyopathie (HCM) hat eine Praevalenz von ca. 0,2% und verlaeuft in vielen Faellen zeitlebens klinisch asymptomatisch. Falls es zur Ausbildung von Symptomen kommt, sind diese oft unspezifisch. Dies erklaert den Stellenwert der Bildgebung bei der Erstdiagnose und Verlaufsbeurteilung der HCM. Leitbefund ist eine myokardiale Hypertrophie mit Wanddicken von {>=} 15 mm. Waehrend die Echokardiographie ein hervorragendes Screeningverfahren ist, erlaubt die MRT eine umfassende Feindiagnostik bei der HCM, zu der gezaehlt werden: eine genaue Darstellung des Verteilungsmusters und des Schweregrads der Hypertrophie, eine detaillierte Analyse der linksventrikulaeren systolischen und diastolischen Funktion, eine Beurteilung und Quantifizierung

  1. Inflammatory lesions of the spinal cord and the nerve roots in magnetic resonance imaging; Entzuendliche Erkrankungen des Rueckenmarks und der Nervenwurzeln in der MRT

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    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.)

  2. Cerebral and meningeal manifestations of AIDS: comparison of plain T2-weighted images and Gd-DTPA enhanced T1-weighted images in 105 patients; Zerebrale und meningeale Manifestationen des AIDS: Vergleich von nativer T2-gewichteter und Gd-DTPA unterstuetzter T1-gewichteter MRT (105 Patienten)

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    Jochens, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany); Henkes, H. [Klinik fuer Radiologische Diagnostik und Neuroradiologie, Alfried Krupp Krankenhaus, Essen (Germany); Steinkamp, H.J. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany); Terstegge, K. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany); Hosten, N. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Standort Wedding, Freie Univ. Berlin (Germany); Ruf, B. [II. Medizinische Klinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin, Standort Wedding (Germany); Schoerner, W. [Inst. fuer Roentgendiagnostik und Nuklearmedizin, Staedtisches Klinikum, Braunschweig (Germany)

    1994-12-31

    The purpose of the present study was to evaluate the potential of T1-weighted Gd-DTPA enhanced MR imaging in the diagnosis of cerebral manifestations of AIDS. 105 patients with AIDS were imaged with plain T2-weighted images as well as with Gd-DTPA enhanced T1-weighted pulse sequences. Our study revealed comparable sensitivities in the detection of morphological changes as shown on plain T2-weighted images and Gd-DTPA enhanced T1-weighted images in 55% of patients (normal and pathologic findings). Plain T2-weighted images were superior in 28.5% and provided significantly better results in 8.5% of patients. Gd-DTPA enhanced T1-weighted images were superior in only 5% cases and revealed significantly better results in 3%. T2-weighted plain images were superior in approximately 40% of patients concerning detection of morphologic changes. In almost 10% of patients with parechymal and meningeal lesions, Gd-DTPA enhanced T1-weighted images, however, were superior or even significantly better compared to T2-weighted plain images. The detection of morphologic changes in MR imaging can be further increased with Gd-DTPA. With regard to differential diagnosis and diesease activity, plain T2-weighted images and Gd-DTPA enhanced T1-weighted images revealed comparable results in 42% of patients (normal and pathologic findings). T2-weighted plain images were superior in 2% of cases whereas Gd-DTPA enhanced T1-weighted images were superior in as much as 56% of patient. MR imaging enhanced with Gd-DTPA yielded additional information on disease activity in 73% of patients with pathologic findings in the cerebral parechyma and the meninges. The surplus of information also refers to the etiology of cerebral pathology and differential diagnosis. Because of the frequency of cerebral manifestations in AIDS, early diagnosis for initiation of therapy and follow-up studies to monitor therapy are crucial. (orig./MG) [Deutsch] Den Stellenwert der T1-gewichteten Gd-DTPA unterstuetzten MRT im

  3. Low-field MRI of the ankle joint-first experience in the pediatric age group; Niederfeld-MRT des Springgelenkes - Erste Erfahrungen bei Kindern und Jugendlichen an einem offenen 0,2 T MR-System

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    Herber, S.; Kreitner, K.F.; Kalden, P.; Loew, R.; Thelen, M. (Klinik und Poliklinik fuer Radiologie); Berger, S. (Klinik und Poliklinik fuer Kinderchirurgie)

    2000-03-01

    Purpose: To evaluate the feasibility and diagnostic confidence of MRI with an open low field System (Magnetom open {sup trademark}, Siemens, Germany) in children with predominantly traumatic disorders. Material and methods: Conventional X-rays and MRI examinations have been evaluated in 55 children. MRI was performed at an open 0.2 T MR-unit. The study protocol comprised coronal STIR-sequence, an angulated T{sub 2} weighted TSE-sequence and T{sub 1} weighted SE-sequence. Results: MRI showed ligamental ruptur in 33/50 (60%) cases. Injuries of the ATFL were most frequent (27/33); osseous ligamental tears occurred in approx. 50% of all cases. Fractures of the distal tibia and fibula were diagnosed in 28/55 children. 15/28 cases showed an involvement of the epiphysis. We found occult fractures in 11/28 children. Fractures, diagnosed by conventional X-rays, were excluded in 6 cases. Therapy changed in 35/55 patients on the basis of MRI-findings. Conclusion: Low-field MRI of the ankle joint in children and adolescents is able to show numerous pathological conditions. We recommend low-field MRI of the ankle in children with persistent or unclear pain of the ankle joint and inconspicuous conventional X-ray. (orig.) [German] Zielsetzung: Bestimmung der Durchfuehrbarkeit und diagnostischen Aussagekraft (Magnetom Open, Siemens {sup trademark}) an Kindern und Jugendlichen mit vorwiegend traumatischen Laesionen des oberen Sprunggelenkes. Material und Methoden: 55 Patienten unterzogen sich zusaetzlich zur konventionellen Roentgendiagnostik einer MRT des oberen Sprunggelenkes. Das Untersuchungsprotokoll beinhaltete eine coronare STIR-Sequenz, T{sub 2}-gewichtete TSE-Sequenzen in anguliert-axialer sowie eine T{sub 1}-gewichtete SE-Sequenz in sagittaler Schnittfuehrung. Das Bildmaterial wurde von zwei Radiologen in Unkenntnis klinischer und/oder operativer Befunde im Konsens ausgewertet. Ergebnisse: Bandrupturen liessen sich in 33/55 (60%) Faellen nachweisen; knoecherne

  4. MR-guided laser-induced interstitial thermotherapy of liver tumors: Clinical experience and therapy control concept; MRT-gestuetzte laserinduzierte Thermoablation bei Lebertumoren - Klinische Aspekte und Konzept eines Ueberwachungssystems

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    Baer, N.K.; Schulz, T.; Puccini, S.; Kahn, T.; Busse, H. [Klinik und Poliklinik fuer Diagnostische Radiologie, Univ. Leipzig (Germany); Schirmer, T. [Applied Science Lab., GE Medical Systems Europe (Germany)

    2003-07-01

    Minimally-invasive, laser-induced interstitial thermotherapy (LITT) of solid tumors represents a valid alternative to surgical procedures such as tumor resections. Within the framework of a palliative study on 16 patients, a total of 25 metastases in the liver were treated in an open MR system (0.5 T). The intraoperative scanner design allows patient-based navigation, decisive for a safe applicator positioning, as well as temperature monitoring and direct inspection of the therapy result, without need for patient transfer or repositioning. Although the MR thermometry applied in the open scanner assisted LITT monitoring, the current accuracy of temperature data was not sufficient to serve automatic irradiation control. Therefore, an experimental monitoring and control system was developed in a closed MR scanner (1.5 T) featuring a calibrated MR thermometry. The system provides also an interface to the laser system, allowing the automatic off/on switching of the laser power according to preoperatively defined control criteria. The basic functionality of the automatic laser control was successfully demonstrated with laser ablation experiments of liver samples using irradiation parameters close to typical clinical values. (orig.) [German] Die laserinduzierte interstitielle Thermotherapie (LITT) solider Tumoren stellt als minimal-invasives Verfahren eine Alternative zur chirurgischen Operation, wie z. B. der Tumorresektion dar. Im Rahmen einer palliativen Studie wurden an 16 Patienten insgesamt 25 Lebermetastasen in einem offenen MRT-System (0,5 T) bestrahlt. Das intraoperative Konzept erlaubt sowohl eine patientenbasierte Navigation, entscheidend fuer eine sichere Applikatorplatzierung, als auch eine Temperaturueberwachung und direkte Therapiekontrolle, ohne dass der Patient umgelagert werden muss. Obwohl die am offenen MRT eingesetzte Thermometrie eine Bestrahlungskontrolle waehrend der LITT gewaehrleistete, reichte die Genauigkeit der gewonnenen Temperaturdaten nicht

  5. Signal changes of bone marrow in MRI under long-term treatment with granulocyte colony-stimulating factors; Veraenderungen des Knochenmarksignals in der MRT unter Langzeittherapie mit Granulozytenkolonie stimulierenden Faktoren

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    Scherer, A.; Engelbrecht, V.; May, P.; Moedder, U. [Duesseldorf Univ. (Germany). Inst. fuer Diagnostische Radiologie; Neises, G. [Duesseldorf Univ. (Germany). Klinik fuer Stoffwechselstoerungen und Ernaehrung; Wendel, U. [Duesseldorf Univ. (Germany). Klinik fuer Allgemeine Paediatrie

    2001-02-01

    Purpose: Recurrent infections in patients with glycogen storage disease (GSD) type lb resulting from an associated neutropenia are frequently treated with granulocyte colony-stimulating factors (G-CSF). The aim of this study was to evaluate the changes occurring in bone marrow by magnetic resonance imaging (MRI) in these patients. Material and Methods: The distal femoral and tibial bones of six patients with GSD lb were evaluated by MRI. Four of these patients were treated with G-CSF for at least 3.9 to a maximum of 8.2 years (mean 5.8 years). The imaging sequences encompassed spin-echo as well as short-time inversion recovery sequences. 4 of the 6 patients had bone marrow aspirations. Results: The patients who had undergone therapy with G-CSF showed a marked increase in signal strength in STIR sequences which encompassed the entire medullar cavity. In T{sub 1}-weighted images these areas were hypointense. Biopsies obtained from these patients showed a bone marrow hypercellularity. The patients without G-CSF therapy showed the same signal intensity changes but with a more discrete and localized pattern in the metaphyseal cavities. Conclusion: In subjects with GSD lb, an increased myelopoetic activity of the bone marrow which is intensified under long-term treatment with G-CSF can be demonstrated by MRI. (orig.) [German] Ziel: Patienten mit Glykogenspeichererkrankung (GSD) Typ lb werden aufgrund einer erhoehten Infektionsneigung bei Leukozytenfunktionsstoerung haeufig mit Granulozytenkolonie stimulierenden Faktoren (G-CSF) behandelt. Unser Ziel war es, bei diesen Patienten Veranderungen des Knochenmarksignals in der MRT zu evaluieren. Material und Methode: Die distalen Ober- und Unterschenkelknochen von 6 Patienten mit GSD lb wurden in der MRT untersucht. Vier dieser Patienten wurden durchschnittlich seit 5,8 Jahren mit G-CSF behandelt, zwei Patienten erhielten keine G-CSF-Therapie. Die Bildgebung umfasste Spin-Echo- sowie Short-time-inversion-recovery (STIR

  6. 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

  7. 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

  8. Influence of stimulus frequency, amplitude and blood pressure on signal change in fMRI; Einfluss von Reizfrequenz, Reizamplitude und Blutdruck auf die Signalantwort in der funktionellen MRT; Untersuchungen am Tiermodell

    Energy Technology Data Exchange (ETDEWEB)

    Hempel, E.; Reith, W.; Elste, V.; Heiland, S.; Sartor, K. [Universitaetsklinikum Heidelberg (Germany). Abt. Neuroradiologie

    1999-03-01

    Purpose: To examine the influence of frequency and amplitude of a stimulus and the effect of blood pressure on signal intensity changes in functional MRI. Methods: Somatosensory stimulation of five (normotonic/hypotonic) anesthetized rats was performed with different stimulus frequencies and amplitudes. Measurements were performed with a 2.4 Tesla experimental scanner using a gradient-echo (GE) echo-planar imaging (EPI) sequence. Results: The highest signal change was found at a frequency of 3 Hz and a stimulation amplitude of ten times the threshold value. A decrease of blood pressure to half the normotonic value gave rise to a decrease of the neuronal response of about 17%. Conclusion: Optimization of the stimulation frequency and stimulation amplitude maximizes signal changes in functional MRI of the somatosensory cortex. Even with a standardized paradigm, variations in measured neuronal activity may occur when blood pressure changes cannot be compensated by autoregulation. (orig.) [Deutsch] Ziel dieser Arbeit war es, die Auswirkungen von Frequenz und Amplitude des Reizimpulses sowie den Einfluss des Blutdrucks auf die Staerke der Signalantwort in der funktionellen MRT zu untersuchen. Methoden: Es wurden 5 narkotisierte Ratten (normotonisch/hypotonisch) mit unterschiedlichen Frequenzen und Reizstromstaerken somatosensorisch stimuliert. Die funktionellen MR-tomographischen Untersuchungen wurden an einem 2,4 Tesla-Experimentalscanner mit einer Gradienten-Echo (GE)-Echo-Planar-Imaging (EPI)-Sequenz durchgefuehrt. Ergebnisse: Die staerkste Signalantwort wurde bei einer Reizfrequenz von 3 Hz und einer Reizstaerke von 10fachem Schwellenwert beobachtet. Die Absenkung des Blutdrucks auf die Haelfte des Normalwertes fuehrte zu einer Signalreduktion um ca. 17%. Schlussfolgerungen: Die Optimierung der Reizintensitaet und Reizfrequenz ermoeglicht eine maximale Signalausbeute in der funktionellen MRT bei somatosensorischer Stimulation. Bei Blutdruckschwankungen am Rande des

  9. Clinical end points for drug treatment trials in BCR-ABL1-negative classic myeloproliferative neoplasms: consensus statements from European LeukemiaNET (ELN) and Internation Working Group-Myeloproliferative Neoplasms Research and Treatment (IWG-MRT).

    Science.gov (United States)

    Barosi, G; Tefferi, A; Besses, C; Birgegard, G; Cervantes, F; Finazzi, G; Gisslinger, H; Griesshammer, M; Harrison, C; Hehlmann, R; Hermouet, S; Kiladjian, J-J; Kröger, N; Mesa, R; Mc Mullin, M F; Pardanani, A; Passamonti, F; Samuelsson, J; Vannucchi, A M; Reiter, A; Silver, R T; Verstovsek, S; Tognoni, G; Barbui, T

    2015-01-01

    The discovery of somatic mutations, primarily JAK2V617F and CALR, in classic BCR-ABL1-negative myeloproliferative neoplasms (MPNs) has generated interest in the development of molecularly targeted therapies, whose accurate assessment requires a standardized framework. A working group, comprised of members from European LeukemiaNet (ELN) and International Working Group for MPN Research and Treatment (IWG-MRT), prepared consensus-based recommendations regarding trial design, patient selection and definition of relevant end points. Accordingly, a response able to capture the long-term effect of the drug should be selected as the end point of phase II trials aimed at developing new drugs for MPNs. A time-to-event, such as overall survival, or progression-free survival or both, as co-primary end points, should measure efficacy in phase III studies. New drugs should be tested for preventing disease progression in myelofibrosis patients with early disease in randomized studies, and a time to event, such as progression-free or event-free survival should be the primary end point. Phase III trials aimed at preventing vascular events in polycythemia vera and essential thrombocythemia should be based on a selection of the target population based on new prognostic factors, including JAK2 mutation. In conclusion, we recommended a format for clinical trials in MPNs that facilitates communication between academic investigators, regulatory agencies and drug companies.

  10. Underground storage with floating cover. An overview; Erdbeckenspeicher mit schwimmender Abdeckung. Eine Uebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Heller, A.; Maureschat, G.; Duer, K. [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Buildings and Energy

    1998-12-31

    A number of underground stores have been developed in recent years in Denmark. The development has been subsidised with funds of `Development program renewable energy` launched by the Danish Ministry for Environment and Energy. First experience reports on underground storage show that more emphasis must be put on the development of storage sealing and cover construction. Hence research works currently focuses on the investigation of liner material and further development of floating cover constructions. The target is the development of underground storage using solar energy for heating that can compete with conventional heating systems technically and economically. (orig.) [Deutsch] In Daenemark hat man in den letzten Jahren eine Reihe von Erdbeckenspeichern entwickelt. Die Entwicklung wird mit Mitteln aus dem `Entwicklungsprogramm Erneuerbare Energie` vom daenischen Umwelt- und Energieministerium finanziell gefoerdert. Die ersten Erfahrungen mit Erdbeckenspeichern haben gezeigt, dass ein verstaerkter Einsatz bei der Entwicklung von Abdichtungen des Speichers und von Deckelkonstruktionen gefordert ist. Deshalb wird in Daenemark aktuell mit der Untersuchung von Linermaterialien und der Weiterentwicklung von schwimmenden Deckelkonstruktionen gearbeitet. Das Ziel dieser Arbeit ist es, Erdbeckenspeicher zu entwickeln, die die Ausnutzung von Sonnenenergie zur Waermeversorgung im Vergleich mit herkoemmlicher Waermeversorgung sowohl technisch als auch oekonomisch konkurrenzfaehig macht. (orig.)

  11. Energy from wood - an overview; Holzenergie, Uebersicht - Energie du bois, apercu du bois

    Energy Technology Data Exchange (ETDEWEB)

    Nussbaumer, T. [Verenum, Zuerich (Switzerland)

    2000-07-01

    The present publication is the introduction to a series of papers on fundamentals and applications of wood energy. It summarizes figures and data of the actual situation of fuel wood utilization in Switzerland and its potential for the future. Further, the advantages of bio-energy are discussed and the possibilities of funding for bio-energy in Switzerland are described. Wood contributes with 2.5% to the total energy demand in Switzerland nowadays. However, the utilization of wood energy can be more than doubled, which is one of the targets of the Swiss energy policy. The supply chains for the different types of fuel wood are described and specifications and prices of log wood, forestry wood chips and wood residues are presented. The main applications of wood energy are residential heating with manually operated wood boilers and stoves, on the one hand, and heat production with automatic wood furnaces in industry and communities, on the other hand. Automatic furnaces have been promoted in the past ten years and hence they contribute nowadays with more than 50% to the energy supply from wood with a further growing share. As an assistance for further information, a list of institutions and addresses in the field of wood energy in Switzerland is given in the paper. (author)

  12. Environmental and human toxicology of nickel - a review; Umwelt- und Humantoxikologie von Nickel - eine aktuelle Uebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Beyersmann, D. [Fachbereich Biologie und Chemie, Univ. Bremen (Germany)

    2006-07-01

    Nickel is a relatively rare element, and its concentrations in ambient air, soils and waters are very low. Higher burdens of nickel are found in nickel industries and their proximity. The human uptake of nickel from the ambient air is neglectably low, except in industrial exposures. The main fraction of human nickel uptake is from food, nearly 50% stems from vegetables. Only about 2% of the oral uptake of nickel are resorbed and distributed over all organs investigated. The uptake of nickel compounds through the skin generally is very low. However, chronic skin contact with nickel and nickel compounds causes a specific contact allergy. This disease was observed after occupational exposure but also frequently in the general population. The number of new cases has dropped considerably due to reinforced prevention. Epidemiological studies with workers of nickel smelting and refining plants have demonstrated increased risks of nose and lung cancer. Human data are supported by results from animal experiments which have shown that inhalation of various nickel compounds caused lung cancer. Furthermore, animal experiments have yielded evidence that oral and inhalative exposure to nickel compounds impair reproduction. National and international agencies have classified various nickel compounds as carcinogenic to humans. The unit cancer risk attributed to life-long inhalation of 1 {mu}g Ni/m{sup 3} air is estimated to be between 2 x 10{sup -4} and 7 x 10{sup -4}. Occupational exposure limits in Germany have been the Technical Guidance Values of 0.5 mg/m{sup 3} for nickel and weakly soluble nickel compounds and of 0.05 mg/m{sup 3} for inhalable droplets of soluble nickel salts. The German limit value for ambient immission is 0.015 mg Ni/m{sup 2}. d, and for emission 0,5 mg Ni/m{sup 3}. Limit values for nickel in air are to be taken not as safe thresholds but as guidance values for the delimitation of the cancer risk. (orig.)

  13. Significance of mercury in environmental health - an overview; Bedeutung von Quecksilber in der Umweltmedizin - eine Uebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Schweinsberg, F. [Chemisches Labor, Institut fuer Allgemeine Hygiene und Umwelthygiene, Tuebingen (Germany)

    2002-07-01

    In addition to occupational exposure to mercury, dental amalgam fillings and fish consumption are the most important sources of mercury body burden in environmental medicine. The principle signs of chronic diseases of the nervous system caused by inorganic mercury are tremor, ataxia, impaired vision and emotional agitation. In the kidneys, tubular necrosis may develop. In patients with severe kidney dysfunction, no amalgam fillings should by inserted. In rare cases, amalgam fillings may cause allergic reactions of the delayed type IV sensitivity and oral lichenoid reactions. Subclinical effects caused by amalgam fillings and their impact on human health is still a topic of controversial discussion. In scientific terms it is not possible to demonstrate a correlation between unspecific symptoms and exposure of mercury released by amalgam fillings. Chronic toxicology of the nervous system caused by organic mercury is characterized by paresthesia, ataxia, dysarthria, constriction of the visual field and hearing impairment. Possible adverse effects on the fetus as a result of the uptake of organic mercury in fish consumption during pregnancy must be critically assessed. The evaluation of adverse health effects brought about by exposure to mercury is assessed in Germany by the definition of human biological monitoring (HBM) values. In long-term exposure to inorganic mercury above the HMB-II value of mercury in urine of 25 {mu}g/L, adverse health effects can arise. The corresponding HMB-II value in blood brought about by organic mercury is 15 {mu}g/L, which is approximately equal to a mercury content of 5 {mu}g/kg in hair. (orig.) [German] Neben dem Arbeitsplatz sind heute im Umweltbereich Amalgamfuellungen und Fischkonsum die wichtigsten Expositionsquellen mit Quecksilber. Leitsymptome einer chronischen Erkrankung des Nervensystems durch anorganisches Quecksilber sind Tremor, Koordinationsstoerungen von Bewegungsablaeufen, Sehstoerungen und Ueberregbarkeit. In den Nieren werden tubulaere Nekrosen gesehen. Bei Patienten mit schwerer Nierenfunktionsstoerung sollte auf Amalgamfuellungen verzichtet werden. Durch Amalgamfuellungen koennen in seltenen Faellen allergische Reaktionen (Spaettyp-IV) und intraorale lichenoide Reaktionen (oraler Lichen ruber planus) ausgeloest werden. Der Nachweis subklinischer Effekte durch Amalgamfuellungen und deren gesundheitliche Bedeutung sind noch immer Gegenstand kontroverser Diskussionen. Die Zuordnung unspezifischer Symptome zu einer Quecksilberbelastung aus Amalgamfuellungen ist wissenschaftlich nicht fundiert moeglich. Eine chronische Erkrankung des Nervensystems durch organisches Quecksilber fuehrt zu Paraesthesie, Ataxie, Dysarthrie, Einschraenkung des Sehfeldes und zu Hoerverlusten. Die Belastung mit Quecksilber waehrend der Schwangerschaft, speziell aus Fischkonsum, ist besonders kritisch zu bewerten. Die gesundheitliche Bewertung von Quecksilberbelastungen erfolgt durch Ableitung von Human-Biomonitoring-Werten (HBM): Bei langzeitiger Exposition mit anorganischem Quecksilber ist ab dem HBM-II-Wert fuer Quecksilber im Urin von 25 {mu}g/l eine gesundheitliche Beeintraechtigung moeglich. Der entsprechende HBM-II-Wert fuer organisches Quecksilber im Blut liegt bei 15{mu}g/l, das entspricht einem Quecksilbergehalt in den Haaren von ca. 5 mg/kg. (orig.)

  14. Pre- and postoperative assessment of hemodynamics in patients with chronic thromboembolic pulmonary hypertension by MR techniques; Erfassung haemodynamischer Parameter bei Patienten mit chronischer thromboembolischer pulmonaler Hypertonie mittels MRT vor und nach Thrombendarteriektomie

    Energy Technology Data Exchange (ETDEWEB)

    Ley, S.; Kauczor, H.U. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Deutsches Krebsforschungszentrum, Heidelberg (Germany). Inst. fuer Radiologie und Pathophysiologie; Kramm, T.; Mayer, E. [Mainz Univ. (Germany). Klinik fuer Herz- Thorax- und Gefaesschirurgie; Heussel, C.P.; Thelen, M.; Kreitner, K.F. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie

    2003-12-01

    -up studies MRI could be considered the modality of choice. (orig.) [German] Ziel: Ziel der Studie war die Beurteilung der prae- und postoperativen funktionellen kardialen Beeintraechtigung und der pulmonalen Hypertension bei Patienten mit chronisch thromboembolischer pulmonaler Hypertonie (CTEPH) mittels MRT im Vergleich zum Rechtsherzkatheter. Material und Methoden: 35 Patienten mit CTEPH wurden vor und nach pulmonaler Thrombendarteriektomie (PTE) untersucht. Haemodynamische Parameter wurden mit Phasenkontrastmessungen in den Pulmonalarterien und der Aorta ascendens (Spitzengeschwindigkeit, Flussvolumen) und Kurzachsen-Cine-Untersuchungen (Ejektionsfraktion (EF)) erfasst. Die Werte von 10 Probanden dienten als Referenzwerte. Die Flussmessungen wurden mit dem im Rechtsherzkatheter bestimmten mittleren pulmonalarteriellen Druck (MPAP) und dem Gefaesswiderstand (PVR) verglichen. Ergebnisse: Patienten mit CTEPH zeigten signifikant reduzierte rechtsventrikulaere EF und pulmonalarterielle Spitzengeschwindigkeiten bei signifikant dilatierten Pulmonalarterien (p<0,001). Nach PTE war der Gefaessdurchmesser signifikant verringert und die Spitzengeschwindigkeit gestiegen (p<0,001). Der Anstieg der Spitzengeschwindigkeit zeigte eine Korrelation von r=0,5 mit der Reduktion des PVR und von r=0,6 mit der Reduktion des MPAP. Die EF des rechten Ventrikels korrelierte linear mit dem PVR (r=0,6) und dem MPAP (r=0,7). Die postoperative Abnahme des MPAP korrelierte mit der Zunahme der EF des rechten Ventrikels (r=0,8). Alle Patienten zeigten praeoperativ eine paradoxe Septumbeweglichkeit. Diese normalisierte sich postoperativ bei 68% der Patienten. Schlussfolgerung: Mittels MR-Techniken ist eine nicht-invasive Abschaetzung der Haemodynamik bei Patienten mit CTEPH moeglich. Fuer postoperative Kontrollen kann die MRT als Modalitaet der Wahl angesehen werden. (orig.)

  15. Multimodal imaging analysis of single-photon emission computed tomography and magnetic resonance tomography for improving diagnosis of Parkinson's disease; Multimodale SPECT- und MRT-Bilddatenanalyse zur Verbesserung der Diagnostik des idiopathischen Parkinson-Syndroms

    Energy Technology Data Exchange (ETDEWEB)

    Barthel, H.; Georgi, P. [Leipzig Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Mueller, U.; Waechter, T.; Murai, T. [Max-Planck-Inst. fuer Neuropsychologische Forschung, Leipzig (Germany); Slomka, P. [Universitaet West-Ontario, London (Canada). Abt. fuer Nuklearmedizin; Dannenberg, C.; Kahn, T. [Leipzig Univ. (Germany). Klinik und Poliklinik fuer Diagnostische Radiologie

    2000-10-01

    impact of [{sup 123}I]{beta}-CIT SPECT for diagnosing PD is affected by the method used to analyze the SPECT images. The described multimodal approach, which is based on coregistration of SPECT and morphological imaging data, leads to improved determination of the degree of this dopaminergic disorder. (orig.) [German] Die dem idiopathischen Parkinson-Syndrom (IPS) zugrunde liegende Degeneration nigrostriataler dopaminerger Neurone kann mit [{sup 123}I]{beta}-CIT und der Single-Photonen-Emissions-Computer-Tomographie (SPECT) erfasst werden. Dabei ist die Qualitaet der bei der Auswertung der SPECT-Studien angewandten Regions-of-Interest-(ROI-)Technik durch die begrenzte anatomische Information in den Szintigrammen limitiert. Die vorliegende Studie wurde durchgefuehrt, um zu testen, ob die Diagnostik des IPS durch eine Koregistrierung der funktionell orientierten SPECT-Bilddaten mit morphologisch orientierten Bilddaten der MRT/CT verbessert werden kann. Dazu wurden im Rahmen einer neurokognitiven Studie 27 Patienten (8 m, 19 w; Alter: 55{+-}13 Jahre) mit IPS (Hoehn-und-Yahr-Stadium 2,1{+-}0,8 [MW{+-}SD]) mittels hochaufloesender [{sup 123}I]{beta}-CIT-SPECT (185-200 MBq, Ceraspect-Kamera) untersucht. Die Spect-Analyse erfolgte durch 2 verschiedene ROI-Techniken: 1. Unimodale Technik - ROIs direkt in den SPECT-Studien definiert; 2. multimodale Technik - ROIs in individuellen MRT/CT-Studien definiert und nach interaktiver Koregistrierung von SPECT- und MRT/CT-Studien auf die SPECT-Studien transformiert. Es wurden [{sup 123}I]{beta}-CIT-Anreicherungsquotienten (Referenz=Zerebellum) fuer die Caudatuskoepfe (CA), Putamina (PU) und fuer die gesamten Corpora striata gewonnen und mit klinischen Parametern verglichen. Im Vergleich zur unimodalen ROI-Technik waren im Falle der multimodalen Technik die Differenzen zwischen den kontra- und ipsilateralen (in Relation zur klinisch dominierenden Halbseite) [{sup 123}I]{beta}-CIT-Anreicherungsquotienten signifikant groesser (z.B. fuer PU

  16. Preoperative functional magnetic resonance tomography (fMRI) in patients with rolandic brain tumors: indication, investigation strategy, possibilities and limitations of clinical application; Praechirurgische funktionelle Magnetresonanztomographie (fMRT) bei Patienten mit rolandischen Hirntumoren: Indikation, Untersuchungsstrategie, Moeglichkeiten und Grenzen der klinischen Anwendung

    Energy Technology Data Exchange (ETDEWEB)

    Stippich, C.; Kress, B.; Ochmann, H.; Sartor, K. [Abt. Neuroradiologie, Neurologische Klinik (Germany); Tronnier, V. [Neurochirurgische Klinik, Universitaetsklinikum Heidelberg (Germany)

    2003-08-01

    Preoperative functional magnetic resonance imaging (fMRI) localizes the primary motor and somatosensory cortex in relation to rolandic brain tumors and determines plastic cortical reorganization. Functional landmarks help to assess the indication for surgery and to plan for safer surgical procedures that protect the functional cortex during resection even when morphologic landmarks are no longer identifiable on anatomic images. Despite its successful application, preoperative fMRI has not yet reached the status of an established clinical diagnostic procedure since special stimulation systems, standardized fMRI protocols and medically approved software are still lacking. Following a brief review of the image display of the functional and morphologic anatomy, the different indications for preoperative fMRI in patients with rolandic brain tumors are presented. A robust preoperative protocol enables clinical MR units with magnetic field strengths of 1.0 Tesla or higher to perform reliable fMRI during contralateral hand movements. Optimized investigation strategies and stimulation modalities are proposed for patients with rolandic tumors distant from the cortical hand representation, for patients with preexisting sensorimotor deficits and for patients with poor compliance. Representative cases illustrate the clinical application. Possibilities and limitations of preoperative fMRI are presented and discussed. (orig.) [German] Die praechirurgische funktionelle Magnetresonanztomographie (fMRT) bildet motorische und somatosensible Hirnaktivierung nicht invasiv in Relation zu rolandischen Tumoren ab und erfasst plastische Veraenderungen. Funktionelle Landmarken ermoeglichen die Pruefung der Operationsindikation sowie die Planung und Durchfuehrung funktionsschonender Resektionen, selbst wenn morphologische Landmarken tumorbedingt nicht mehr identifizierbar sind. Derzeit kann die fMRT noch nicht als klinisch etabliertes diagnostisches Verfahren angesehen werden, da praktikable

  17. New aspects of MRI for diagnostics of large vessel vasculitis and primary angiitis of the central nervous system; Neue Aspekte der MRT-Bildgebung zur Diagnostik der Grossgefaessvaskulitiden sowie der primaeren Angiitis des zentralen Nervensystems

    Energy Technology Data Exchange (ETDEWEB)

    Saam, T.; Habs, M.; Cyran, C.C.; Grimm, J.; Reiser, M.F.; Nikolaou, K. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Pfefferkorn, T. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Klinik und Poliklinik fuer Neurologie, Muenchen (Germany); Schueller, U. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Zentrum fuer Neuropathologie, Muenchen (Germany)

    2010-10-15

    der Gefaesswand zu, allerdings sind nur ausgewaehlte extrakranielle Gefaesse mit ausreichender Aufloesung schallbar. Da den Vaskulitiden primaer Veraenderungen der Gefaesswand zugrunde liegen und die gefundenen luminalen Veraenderungen in der Regel unspezifisch sind und auch bei anderen Erkrankungen auftreten koennen, sind die gebraeuchlichen Verfahren in ihrer Aussagekraft oft limitiert. Mit der hochaufgeloesten MRT der zervikalen und intrakraniellen Gefaesse steht eine viel versprechende neue Methode zur Verfuegung, die die entzuendlich veraenderte Gefaesswand nichtinvasiv und ohne Verwendung ionisierender Strahlen im Detail zu visualisieren vermag. In diesem Beitrag sollen die verwendeten Untersuchungsprotokolle vorgestellt und klinische Bildbeispiele gezeigt werden. Dabei sollen insbesondere die Grossgefaessvaskulitiden und die Vaskulitiden des ZNS behandelt werden. Zudem werden die haeufigsten radiologischen Differenzialdiagnosen demonstriert und andere bildgebende Methoden, wie PET/CT und Ultraschall, die ebenfalls zur Diagnostik der Vaskulitiden eingesetzt werden, diskutiert. (orig.)

  18. MRT fuel element inspection at Dounreay

    International Nuclear Information System (INIS)

    Gibson, J.

    1997-01-01

    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

  19. Malignoma versus infectious spondylodiscitis in a case of progressive paraplegia: the value of an emergency MRI of the spine for the differential diagnosis; Malignom versus bakterielle Spondylodiszitis: Bedeutung der spinalen MRT fuer die Differentialdiagnose in der Notfallsituation. Beschreibung einer akuten Querschnittssymptomatik

    Energy Technology Data Exchange (ETDEWEB)

    Bremer, M.; Karstens, J.H. [Medizinische Hochschule Hannover (Germany). Abt. fuer Strahlentherapie und Spezielle Onkologie; Herzog, T. [Medizinische Hochschule Hannover (Germany). Abt. fuer Neuroradiologie

    1997-12-01

    Patient and Method: A case of an elderly diabetic patient with acute onset of a progressive neurologic deficit is reported. No malignancy was known so far. The CT of the spine showed a destruction of the 7th and 8th toracic vertebral body with compression of the spinal cord. The patient was referred to the radiotherapist for radiation of a presumed malignant spinal process. Result: For differential diagnosis a magnetic resonance imaging (MRI) of the spine was performed and could lead to the correct diagnosis of an infectious spondylodiscitis. Conclusion: The MRI of the spine has a potential role for correct differentiation between benign and malignant spinal lesions and may thereby assist the radiotherapist in the dicision making in an emergency situation. (orig./MG) [Deutsch] Patient und Methode: Vorgestellt wird eine 70jaehrige Patientin mit akut aufgetretener, progredienter Paraparese beider Beine. Anamnestisch fand sich neben einem Diabetes und einer Osteoporose kein Hinweis auf eine Tumorerkrankung. Aufgrund der im spinalen CT imponierenden ossaeren Destruktion des siebten und achten Brustwirbelkoerpers mit Einengung des Spinalkanals erfolgte unter der Annahme eines Malignoms die Vorstellung beim Strahlentherapeuten. Ergebnis: Erst die vom Radioonkologen im Notfalldienst veranlasste spinale Kernspintomographie (MRT) konnte ein Malignom ausschliessen und ergab die Diagnose einer infektioesen Spondylodiszitis. Schlussfolgerungen: Die spinale MRT kann in einer Situation mit aktuer Querschnittssymptomatik unklarer Aetiologie die entscheidenden differentialdiagnostischen Hinweise liefern und damit im Notfalldienst zur Absicherung einer Bestrahlungsindikation beitragen. (orig./MG)

  20. Comparison of high resolution whole-body MRI using parallel imaging and PET-CT. First experiences with a 32-channel MRI system; Hochaufloesendes Ganzkoerpertumorstaging unter Verwendung paralleler Bildgebung im Vergleich zur PET-CT. Erste Erfahrungen auf einem 32-Kanal-MRT-System

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, G.P.; Baur-Melnyk, A.; Reiser, M.F.; Schoenberg, S.O. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Klinische Radiologie (Germany); Tiling, R.; Hahn, K. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen, Klinik und Poliklinik fuer Nuklearmedizin (Germany)

    2004-09-01

    technique in the detection of primary tumor and metastatic disease. Sensitivity in the assessment of lymph node metastases seems to be limited. With the use of parallel imaging (iPAT), dedicated high-resolution whole-body MRI is possible within acceptable scanning times. (orig.) [German] Vergleich der Genauigkeit eines hochaufloesenden Ganzkoerper-MRT-Tumorstagings unter Verwendung paralleler Bildgebung mit den Ergebnissen der PET-CT. Es werden erste Ergebnisse einer Interimsanalyse aus einer prospektiven, geblindeten Studie vorgestellt, in der an 20 Patienten (Durchschnittsalter 59 Jahre, Range 27-77 Jahre) mit unterschiedlichen onkologischen Erkrankungen im Rahmen der klinischen Diagnostik eine Tumor- oder Metastasensuche mit der Ganzkoerper-FDG-PET-CT durchgefuehrt wurde. Bei allen Patienten erfolgte zusaetzlich eine Ganzkoerper-MRT-Bildgebung mit Einsatz der parallelen Bildgebungstechnik (iPAT). Angewendet wurden hochaufloesende koronare T1-gewichtete- und STIR-Sequenzen von 5 Koerperregionen mit einer Matrix von 512 x 512 mm, axiale T2-gewichtete Turbospinechosequenzen (HASTE) der Lunge und des Abdomens sowie kontrastverstaerkte dynamische und statische T1-gewichtete Sequenzen von Leber, Gehirn, Abdomen und Becken. Bei Verwendung eines 32-Kanal-Systems (Magnetom Avanto, Siemens Medical Solutions) mit einem gesamten field of view von 205 cm und freier Tischbewegung konnten alle Patienten in einem Untersuchungsgang vollstaendig von Kopf bis zu den Fuessen gescannt werden. Dabei wurde eine hohe raeumliche Aufloesung erzielt. Die Messzeit betrug ca. 55 min. Zwei erfahrene Radiologen werteten die MRT-Untersuchung, ein Radiologe und ein Nuklearmediziner die PET-CT-Untersuchung, jeweils im Konsensus, aus. Es wurden der Nachweis und das Stadium des Primaertumors oder des Tumorrezidivs sowie von Lymphknoten- und Fernmetastasen bewertet. Als Referenzmethode wurde das durch die PET-CT identifizierte TNM-Stadium herangezogen. Es wurden Metastasen von gastrointestinalen Tumoren (25

  1. Use of SPIO-enhanced T{sub 1} and T{sub 2}-weighted images for the differentation of liver lesions: an ROC analysis; Differenzierung von Leberlaesionen mit SPIO-gestuetzten T{sub 1}-w und T{sub 2}-w MRT Aufnahmen: Eine ROC-Analyse

    Energy Technology Data Exchange (ETDEWEB)

    Stroszcynski, C.; Gaffke, G.; Gebauer, B.; Felix, R. [Virchow Klinikum, Berlin (Germany). Klinik und Poliklinik fuer Strahlenheilkunde; Charite Campus Buch, Berlin (Germany). Klinik und Poliklink fuer Strahlenheilkunde; Gretschel, S.; Hohenberger, P. [Charite Campus Buch, Berlin (Germany). Klinik fuer Chirurgie und Chirurgische Onkologie; Rambow, A.; Jost, D.; Schlecht, I. [Charite Campus Buch, Berlin (Germany). Klinik und Poliklink fuer Strahlenheilkunde; Schneider, U. [Charite Campus Buch, Berlin (Germany). Inst. fuer Pathologie; Schicke, B. [Tumorzentrum Berlin Buch, Berlin (Germany). Statistik und Informatik

    2003-10-01

    Purpose: The superparamagnetic iron oxide (SPIO) Resovist {sup trademark} is a contrast media with shortening of both T{sub 1} and T{sub 2} relaxation time. This study evaluates the impact of SPIO-enhanced T{sub 1}- and T{sub 2} weighted images for the differentiation of liver lesions. Materials and methods: SPIO-enhanced MRI examinations (1.5 T, Symphony Quantum) of 61 patients were analyzed. Thirty-seven patients had malignant liver lesions (metastases n=32, HCC n=5) proven by biopsy or laparotomy, 11 patients had benign liver lesions (FNH n=2, hemangiomas n=4, benign cysts n=5, normal liver on laparoscopy n=13). After unenhanced T{sub 1}- and T{sub 2}-weighted imaging, a bolus injection of 1.4 ml SPIO (Resovist {sup trademark}) was given, followed by T{sub 1}-weighed imaging at 20s, 60s, and 5 min and T{sub 2}-weighted imaging at 10 min post injection. A score from 1 (benign) to 5 (malignant) was used by three blinded radiologists for the ROC analysis of the unenhanced T{sub 1}/T{sub 2}-weighted images (set 1) and of the combination of unenhanced T{sub 1}/T{sub 2}-weighted and SPIO T1-weighted images (set 2), unenhanced T{sub 1}/T{sub 2} and SPIO T{sub 2}-weighted images (set 3) and all images (set 4). Results: The accuracy of plain MRI (set 1: 56%) was increased by SPIO-enhanced T{sub 1}-weighted images (set 2: 81%) and SPIO-enhanced T{sub 2}-weighted images (set 3: 90%). Best results were obtained using unenhanced T{sub 1}-weighted, unenhanced T{sub 2}-weighted and both SPIO T{sub 1}-weighted and T{sub 2}-weighted images (set 4: 93%). The accuracy of predicting histopathologic diagnosis was 91%. (orig.) [German] Ziel: Resovist {sup trademark} ist ein superparamagnetische Eisenoxid (SPIO) mit T{sub 1} und T{sub 2} Effekten. Ziel dieser Studie war die Evaluation des Einflusses SPIO-unterstuetzter T{sub 1}-w und T{sub 2}-w Aufnahmen auf die Differenzierung von Leberlaesionen. Methode: Es wurden 61 Patienten mit einer SPIO-unterstuetzten MRT (1,5 T) der Leber

  2. Biomass based energy. A review on raw materials and processing methods; Energie aus Biomasse. Eine Uebersicht ueber Rohstoffe und Verfahren

    Energy Technology Data Exchange (ETDEWEB)

    Woellauer, P.

    2007-07-01

    The book reviews the variety of biogenic raw materials and the technologically important biomass conversion techniques. The chapter on the different kinds of biomass includes a) wood from forestry, landscape culturing and saw mills, bark and old wood; b) plants (corn, miscanthus, cannabis, wheat, rye, sugar beets, grass, rape, etc.), residuals and wastes (straw, liquid manure, slaughthouse wastes, kitchen wastes, sewage sludge, others). The chapter on biomass conversion processing discusses combustion, oxidation in spercritical water, gasification and reforming, fermentation, extrusion or extraction, and downstream processes. The chapter on biomass based electricity and mechanical energy includes refrigeration engineering, direct utilization: Otto engines, Diesel engines, microgas turbine fuel cells, and heat processing: Striling engine, vapour turbine, ORC turbine, externally fired gas turbine, and the Kalina process.

  3. Endovascular brachytherapy to prevent restenosis after angioplasty; Endovaskulaere Brachytherapie in der Restenoseprophylaxe nach Angioplastie und Stentimplantation: Eine Uebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgemuth, W.A.; Bohndorf, K. [Klinikum Augsburg (Germany). Klinik fuer Diagnostische Radiologie und Neuroradiologie

    2003-02-01

    Endovascular radiotherapy is the first effective prophylaxis of restenosis after percutaneous transluminal angioplasty (PTA) and stenting. The FDA recently approved two devices for the delivery of intracoronary radiation following coronary artery stenting. Published multicenter, double-blind, randomized trials of intracoronary radiation therapy report good results for preventing in-stent restenosis, while the data for the peripheral circulation are still inconclusive. Beta-emitters are easier applicable and probably also safer, whereas gamma-emitters have been more extensively evaluated clinically so far. Primary indication for endovascular brachytherapy are patients at high risk for restenosis, such as previous restenoses, in-stent hyperplasia, long stented segment, long PTA lesion, narrow residual vascular lumen and diabetes. Data from coronary circulation suggest a safety margin of at least 4 to 10 mm at both ends of the angioplastic segment to avoid edge restenosis. To prevent late thrombosis of the treated coronary segment, antiplatelet therapy with clopidogrel and aspirin are recommended for at least 6 months after PTA and for 12 months after a newly implanted stent. An established medication regimen after radiotherapy of peripheral arteries is still lacking. (orig.) [German] Die endovaskulaere Radiotherapie stellt das erste erfolgreiche Therapiekonzept in der Restenoseprophylaxe nach PTA und Stentimplantation dar. Am 3.11.2000 hat die amerikanische Food and Drug Administration erstmalig zwei Brachytherapiegeraete zur Restenoseprophylaxe nach Koronararterien-Stenting zugelassen. Grosse multizentrische, kontrollierte Studien wurden fuer das koronare Stromgebiet mit positiven Ergebnissen publiziert, die Datenlage im peripheren Stromgebiet ist noch ungenuegend. Beta-Strahler bieten Vorteile in der Anwendung, moeglicherweise auch in der Sicherheit, Gamma-Strahler dagegen sind besser klinisch evaluiert. Die primaere Indikation zur endovaskulaeren Brachytherapie besteht bei Patienten mit erhoehtem Risiko eine Restenose wie beispielsweise einer Rezidivstenose, einer In-Stent-Hyperplasie, langen ueberstenteten Laesionen, einer langen PTA-Strecke, kleinen Restlumina und Patienten mit Diabetes mellitus. Daten aus dem koronaren Stromgebiet legen nahe, dass waehrend der Bestrahlung ein Sicherheitsabstand von mindestens 4-10 mm beidseits der durch PTA traumatisierten Gefaessstrecke eingehalten werden sollte, um Restenosen an den Bestrahlungsraendern zu vermeiden. Zur Prophylaxe einer Spaetthrombosierung nach Bestrahlung wird im koronaren Stromgebiet eine medikamentoese Begleittherapie mit ASS 100 mg und Clopidogrel 75 mg taeglich ueber mindestens 6 Monate nach PTA und 12 Monate nach Stentneumimplantation empfohlen, gesicherte Erkenntnisse fuer periphere Arterien existieren noch nicht. (orig.)

  4. MRI of the hip joint; MRT des Hueftgelenks

    Energy Technology Data Exchange (ETDEWEB)

    Czerny, C.; Noebauer-Huhmann, I.M.; Imhof, H. [Universitaetsklinik fuer Radiodiagnostik, Medizinische Univ. Wien (Austria)

    2005-12-01

    Magnetic resonance imaging (MRI) is performed to diagnose many pathologic conditions affecting the hip joint. Either conventional MRI (without contrast enhancement of the joint cavity) or MR arthrography is used to detect and most accurately differentiate hip joint pathologies. Conventional MRI is performed in cases of bone marrow edema, necrosis, arthrosis and especially the so-called ''activated arthrosis'', as well as in inflammatory and tumorous entities. MR arthography, which has only recently become available for use, is excellently suited for diagnosing lesions of the acetabular labrum, cartilage lesions, and free articular bodies. This article provides an overview about MRI characteristics and their accuracy of hip joint diseases and the impact on the therapeutic procedure. (orig.)

  5. Dental magnetic resonance imaging; MRT der Zaehne und des Zahnhalteapparats

    Energy Technology Data Exchange (ETDEWEB)

    Hilgenfeld, Tim; Bendszus, Martin; Haehnel, Stefan [Universitaetsklinikum Heidelberg (Germany). Abt. fuer Neuroradiologie

    2016-03-15

    Growing distribution and utilization of digital volume tomography (DVT) extend the spectrum of clinical dental imaging. Additional diagnostic value, however, comes along with an increasing amount of radiation. In contrast, magnetic resonance imaging is a radiation free imaging technique. Furthermore, it offers a high soft tissue contrast. Morphological and numerical dental anomalies, differentiation of periapical lesions and exclusion of complications of dental diseases are field of applications for dental MRI. In addition, detection of caries and periodontal lesions and injury of inferior alveolar nerve are promising application areas in the future.

  6. Essentials of clinical MRI; Essentials der klinischen MRT

    Energy Technology Data Exchange (ETDEWEB)

    Attenberger, Ulrike I.; Schoenberg, Stefan O. (eds.) [Heidelberg Univ. Universitaetsmedizin Mannheim (Germany). Inst. fuer Klinische Radiologie und Nuklearmedizin; Runge, Val M. [Univ. of Texas Medical Branch (UTMB), Galveston, TX (United States). Dept. of Radiology; Morelli, John N. [Texas A and M Univ., Temple, TX (United States). Dept. of Radiology

    2011-07-01

    The text book on practical magnetic resonance imaging includes the following chapters: brain; cervical spine; thoracic spine; lumbar spine; head and neck; heart and thorax; mammary glands; abdomen and pelvis; musculoskeletal system; MRI contrast media; magnetic resonance angiography.

  7. Whole body MRI in children; Ganzkoerper-MRT bei Kindern

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, Juergen F.; Tsiflikas, Ilias [Tuebingen Univ. (Germany). Bereich Kinderradiologie

    2014-09-15

    In pediatric patients whole body MRI has a relevant impact on both, diagnostic work-up and treatment. Using adapted sequence protocols comprehensive imaging without radiation exposure is possible avoiding additional examinations in many cases. Especially in bone marrow the differentiation between normal and abnormal finding can be difficult, therefore the knowledge of normal maturing of organs is important. Whole body diffusion weighted imaging particularly in neuroblastomas or sarcomas improves the low specificity of conventional MR-protocols. Technical prerequisites, examination protocol and strategies, image interpretation, indications and clinical relevance as well as advantages and disadvantages of whole body MRI will be discussed on the basis of application-oriented cases and the literature.

  8. MR imaging of bone marrow edema. Knochenmarkoedem in der MRT

    Energy Technology Data Exchange (ETDEWEB)

    Vahlensieck, M.; Reiser, M. (Bonn Univ. (Germany). Radiologische Klinik)

    1992-10-01

    Like other vascularized organs, bone can react with increasing interstitial fluid to disturbances in permeability caused by various noxae. Signs of bone marrow edema recognizable in magnetic resonance imaging are described for conditions such as trauma, stress, reflex sympathetic dystrophy, ischemia, and infection. A bone marrow edema may by an early or the only sign of a disease entity visible solely on MR images. We made a retrospective study of musculoskeletal MR examinations conducted over a period of 3 months to estimate the incidence of bone marrow edema. (orig.).

  9. Molecular imaging in cardiovascular diseases; Molekulare kardiovaskulaere MRT-Bildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Botnar, R.M. [King' s College London (United Kingdom). Imaging Sciences; St. Thomas' NHS Foundation Trust, London (United Kingdom); Ebersberger, H. [Heart Center Munich-Bogenhausen, Munich (Germany). Dept. of Cardiology and Intensive Care Medicine; Noerenberg, D. [Charite, Berlin (Germany). Inst. for Radiology; and others

    2015-02-15

    Cardiovascular diseases remain the leading cause of morbidity and mortality in industrialized and developing countries. In clinical practice, the in-vivo identification of atherosclerotic lesions, which can lead to complications such as heart attack or stroke, remains difficult. Imaging techniques provide the reference standard for the detection of clinically significant atherosclerotic changes in the coronary and carotid arteries. The assessment of the luminal narrowing is feasible, while the differentiation of stable and potentially unstable or vulnerable atherosclerotic plaques is currently not possible using non-invasive imaging. With high spatial resolution and high soft tissue contrast, magnetic resonance imaging (MRI) is a suitable method for the evaluation of the thin arterial wall. In clinical practice, native MRI of the vessel wall already allows the differentiation and characterization of components of atherosclerotic plaques in the carotid arteries and the aorta. Additional diagnostic information can be gained by the use of non-specific MRI contrast agents. With the development of targeted molecular probes, that highlight specific molecules or cells, pathological processes can be visualized at a molecular level with high spatial resolution. In this review article, the development of pathophysiological changes leading to the development of the arterial wall are introduced and discussed. Additionally, principles of contrast enhanced imaging with non-specific contrast agents and molecular probes will be discussed and latest developments in the field of molecular imaging of the vascular wall will be introduced.

  10. Transmyocardial laser revascularization - first experiences of imaging in MRT

    International Nuclear Information System (INIS)

    Weber, C.; Maas, R.; Steiner, P.; Beese, M.; Hvalic, M.; Buecheler, E.; Stubbe, M.

    1998-01-01

    Purpose: Imaging of myocardial signal alteration and perfusion differences after transmyocardial laser revascularization (TMLR). Methods and Material: 5 patients suffering from coronary vessel disease underwent MRI (0.5 T) pre- and 4-7 d post-TMLR. T 1 -weighted spin echo sequences were acquired ECG-triggered native and after injection of gadolinium. Qualitative analysis was performed on both native and contrast-enhanced images. Myocardial signal alterations and wall changes were evaluated. Qualitative and quantitative analyses of contrast-enhanced images were performed with regard of post therapeutic perfusion differences. Analysis was based on contrast-to-noise (C/N) data obtained from operator defined 'regions of interest'. Results: Visualization of laser-induced channels was not possible. Native scans obtained before and after TMLR revealed no significant change with regard to the qualitative analysis. Both qualitative and quantitative analyses demonstrated a posttherapeutic increase of C/N in both the left ventricular myocardium (64.4 pre-TMLR; 89.1 post-TMLR; p=0.06) and the septum in the majority of cases. No significant difference between laser-treated left myocardium and untreated septum was observed (p>0.05). Discussion: Single myocardial laser channels could not be visualized with a 0.5-T MRI. However, visualization of increased myocardial contrast enhancement in laser-treated left ventricular myocardium was evident in the majority of cases on the basis of qualitative and quantitative analyses. Conclusions: The MRI technique used enabled a first, limited depiction of TMLR-induced myocardial changes. The clinical value and impact still have to be defined. (orig.) [de

  11. Diagnostic radiology of osteo-articular lesions; Radiologie der Knochen- und Gelenkerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Heuck, A. [ed.

    1997-07-01

    The textbook teaches the fundamentals as well as the ins and outs of diagnostic image analysis and hence may also serve as a reference book, e.g. for information on lesions of rare occurrence. It offers easy and rapid access to the systematically arranged material covering all relevant methods and findings. (orig./CB) [German] Gerade Anfaenger werden gerne an den 'Knochenplatz' gesetzt - und stellen dann fest, wie schwierig die exakte Analyse der konventionellen Bilder und wie gross die Zahl der Differentialdiagnosen ist. Dieses Buch lehrt die Grundlagen und Feinheiten der Bildanalyse und kann auch als konzentriertes Nachschlagewerk, z.B. zu seltenen Erkrankungen, genutzt werden. Durch CT und MRT ist die radiologische Beurteilung der Knochen- und Gelenkerkrankungen in vieler Hinsicht verbessert, fuer den einzelnen aber auch noch unueberschaubarer geworden. Dieses Buch bringt Uebersicht und Systematik in die Vielfalt der Methoden und Befunde. (orig.)

  12. Comparison of left and right ventricular ejection and filling parameters by fast cine MR imaging in breath-hold technique: clinical study of 42 patients with cardiomyopathy and coronary heart disease; Vergleich links- und rechtsventrikulaerer Auswurf- und Fuellungsparameter des Herzens mittels Cine MRT in Atemanhaltetechnik: klinische Studie an 42 Patienten mit Kardiomyopathie und koronarer Herzerkrankung

    Energy Technology Data Exchange (ETDEWEB)

    Rominger, M.B.; Bachmann, G.F.; Geuer, M.; Puzik, M.; Rau, W.S. [Giessen Univ. (Germany). Diagnostische Radiologie; Ricken, W.W. [Kerckhoff-Klinik GmbH, Bad Nauheim (Germany). Abt. Kardiologie

    1999-06-01

    )/s) der Zeitpunkt der MAR und MFR (Z-MAR, ZMFR ms) und der Zeitpunkt der Endsystole (Z-SYS in % RR-Intervall) berechnet wurden. Ergebnisse: Innerhalb und zwischen den verschiedenen Gruppen gab es signifikante regionaere und seitenbezogene Unterschiede der Auswurf- und Fuellparameter der Ventrikel. Bei der DCM ist die MFR linksventrikulaer eingeschraenkt (DCM 3,1 EDV/s; Probanden: 4,9 EDV/s) und die Z-SYS verlaengert (DCM 50,1%; Probanden 35,4%). In der KHK-Gruppe ergaben sich regional eingeschraenkte maximale Fuellraten im Vergleich zum Probandenkollektiv (linksventrikulaer: Basis: 2,9 versus 4,2 EDV/s, Spitze: 4,4 vs. 6,3 EDV/s; rechtsventrikulaer 3,6 vs. 5,7 EDV/s). Typisch fuer die HCM war eine verlaengerte isovolumetrische Endsystole. Schlussfolgerungen: Die kardiale Cine MRT in Atemanhaltetechnik ist geeignet, Stoerungen der Kontraktion und Relaxation beider Ventrikel bei regionalen und diffusen Erkrankungen des Myokards anhand von verschiedenen Auswurf- und Fuellparametern quantitativ zu erfassen. (orig.)

  13. Overview on available animal models for application in leukemia research; Uebersicht ueber vorhandene Tiermodelle, die fuer die Leukaemieforschung angewandt werden koennten

    Energy Technology Data Exchange (ETDEWEB)

    Borkhardt, A.; Sanchez-Garcia, I.; Cobaleda, C.; Hauer, J.

    2015-01-15

    The term ''leukemia'' encompasses a group of diseases with a variable clinical and pathological presentation. Its cellular origin, its biology and the underlying molecular genetic alterations determine the very variable and individual disease phenotype. The focus of this review is to discuss the most important guidelines to be taken into account when we aim at developing an ''ideal'' animal model to study leukemia. The animal model should mimic all the clinical, histological and molecular genetic characteristics of the human phenotype and should be applicable as a clinically predictive model. It should achieve all the requirements to be used as a standardized model adaptive to basic research as well as to pharmaceutical practice. Furthermore it should fulfill all the criteria to investigate environmental risk factors, the role of genomic mutations and be applicable for therapeutic testing. These constraints limit the usefulness of some existing animal models, which are however very valuable for basic research. Hence in this review we will primarily focus on genetically engineered mouse models (GEMMs) to study the most frequent types of childhood leukemia. GEMMs are robust models with relatively low site specific variability and which can, with the help of the latest gene modulating tools be adapted to individual clinical and research questions. Moreover they offer the possibility to restrict oncogene expression to a defined target population and regulate its expression level as well as its timely activity. Until recently it was only possible in individual cases to develop a murin model, which fulfills the above mentioned requirements. Hence the development of new regulatory elements to control targeted oncogene expression should be priority. Tightly controlled and cell specific oncogene expression can then be combined with a knock-in approach and will depict a robust murine model, which enables almost physiologic oncogene expression, subsequently mimics the human phenotype in detail and hence fulfills the requirements of an ''ideal'' animal model.

  14. Occurrence, use and protection of thermal water and mineral water in Aargau - An overview; Vorkommen, Nutzung und Schutz von Thermalwaessern und Mineralwaessern im Kanton Aargau: eine Uebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Burger, H. [Departement Bau, Verkehr und Umwelt des Kantons Aargau, Abteilung fuer Umwelt, Aarau (Switzerland)

    2009-07-01

    This article in the Swiss Bulletin for Practical Geology takes a look at the occurrence, use and protection of thermal water and mineral water in the Canton of Aargau in Switzerland. The author notes that this Swiss canton is rich in mineral water resources and spas. The article presents an overview of the most important resources and takes a look at possible conflicts of goals and trade-offs concerning the use and protection of these resources. Measurements made concerning various factors such as trace gases, medicinal properties and other, physical characteristics of the mineral waters are discussed. Thermal waters in the Baden, Zurzach and Schinznach areas are discussed in more detail, as are artesian springs in the upper Rhine valley. Springs in shell-limestone areas and in the gravel beds of central Switzerland are also commented on. Finally, protection measures are discussed.

  15. Review of preliminary results of the project `Co-cracking of plastics and petroleum residues`; Uebersicht zu den ersten Ergebnissen des Projektes Cocracking von Kunststoffen und Erdoelrueckstand

    Energy Technology Data Exchange (ETDEWEB)

    Uhmann, R.; Koepsel, R.F.; Kuchling, T.; Simanjenkov, V. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Energieverfahrenstechnik und Chemieingenieurwesen

    1998-09-01

    Coprocessing of petroleum residues and plastics is a promising technology, although some problems concerning waste plastics must be clarified prior to its implementation. In general, it can be stated that with a careful choice of operating parameter combinations, oil yields will be higher than for thermal treatment of petroleum residues alone (e.g. a 35% yield increase is achieved by adding 25% of plastics, which is a disproportionately high increase). Waste plastics thus become a valuable material for processing. (orig.) [Deutsch] Das untersuchte Coprocessing von VR und Kunststoffen ist ein erfolgversprechender Weg der Kunststoffverwertung und des tiefen Crackens von Erdoelrueckstand. Die Klaerung der mit Altkunststoffen verbundenen Fragen bedarf weiterer Untersuchungen. Allgemein kann festgestellt werden, dass bei entsprechenden Parameterkombinationen bessere Oelausbeuten erzielt werden als bei der thermischen Behandlung von reinem VR. Ein Beispiel dafuer ist in der Abbildung 10 dargestellt. Durch eine 25%-ige Erhoehung der Einsatzstoffmasse durch Kunststoffzugabe wird eine im Vergleich zu reinem VR um ca. 36% hoehere Oelausbeute erzielt, was einer ueberproportionalen Erhoehung entspricht. Altkunststoff wird bei diesem Prozess unter Nutzung des Wasserstoff-potentials von Polymeren zu einem wertvollen Einsatzstoff. (orig.)

  16. Magnetic resonance imaging of complex congenital heart disease in aduits; Magnetresonanztomographie komplexer kongenitaler Herzerkrankungen beim Erwachsenen

    Energy Technology Data Exchange (ETDEWEB)

    Bremerich, J. [San Francisco Univ, CA (United States). Dept. of Radiology]|[Universitaetsklinik Basel (Switzerland). Abt. fuer Medizinische Radiologie; Wyttenbach, R.; Higgins, C.B. [San Francisco Univ, CA (United States). Dept. of Radiology; Buser, P. [Universitaetsklinik Basel (Switzerland). Abt. fuer Kardiologie; Steinbrich, W. [Universitaetsklinik Basel (Switzerland). Abt. fuer Medizinische Radiologie

    1999-04-01

    An increasing number of patients with complex congenital heart disease reaches adulthood, because treatment and patient outcome have improved considerably in recent years. Monitoring of these patients requires both definition of cardiac anatomy and assessment of function with good reproducibility. Complications after surgical repair such as restenoses of pulmonary arteries after surgical repair of Tetralogy of Fallot, ventricular hypertrophy, stenoses or leakage of baffles, or stenosis and aneurysms of anastomoses have to be detected at an early stage. Magnetic Resonance Imaging (MRI) is an excellent tool to monitor these patients because of its noninvasive nature, its good interstudy and interobserver reproducibility, and because it allows assessment of both cardiac anatomy and function. This paper reviews the current applications of MRI in complex congenital heart disease in adults. (orig.) [Deutsch] Durch Verbesserungen in der Diagnose und Therapie komplexer kongenitaler Herzerkrankungen kann eine zunehmende Anzahl von betroffenen Patienten das Erwachsenenalter erreichen. Diese Patienten benoetigen regelmaessige postoperative Verlaufskontrollen, um Komplikationen wie z.B. Restenosen der grossen Arterien, Stenosen, Lecks und Aneurysmata von Anastomosen, Ventrikelhypertrophie und -dilatation oder Klappendysfunktionen fruehzeitig zu erkennen und zu behandeln. Fuer nichtinvasive regelmaessige Verlaufskontrollen bietet sich die Magnetresonanztomographie (MRT) des Herzens an, da sie eine umfassende Untersuchung sowohl der Morphologie als auch der Funktion des Herzens mit guter Reproduzierbarkeit erlaubt. Die gegenwaertigen klinischen Anwendungen der MRT bei komplexen kongenitalen Herzerkrankungen beim Erwachsenen werden in dieser Uebersicht beschrieben. (orig.)

  17. Primary liver tumors. Hepatocellular versus intrahepatic cholangiocellular carcinoma; Primaere Lebertumoren. Hepatozellulaeres vs. intrahepatisches cholangiozellulaeres Karzinom

    Energy Technology Data Exchange (ETDEWEB)

    Wengert, G.J.; Bickel, H.; Breitenseher, J.; Ba-Ssalamah, A. [Medizinische Universitaet Wien, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Allgemeines Krankenhaus, Wien (Austria)

    2015-01-01

    Epidemiologie, Aetiologie, Risikofaktoren und charakteristische Merkmale der radiologischen Methodik (MRT, Multidetektor-CT) und Bildmorphologie sowie Screeningaspekte vorgestellt und diskutiert. Weiter wird auf das Karzinogenesemodell beider Tumoren, mit dem Ursprung aus einer pluripotenten Stammzelle, eingegangen. Durch innovative Weiterentwicklung moderner multiparametrischer Schnittbildverfahren, insbesondere der MRT in Kombination mit diffusionsgewichteten Sequenzen und Applikation hepatobiliaerer Kontrastmittel, werden eine nichtinvasive Frueherkennung, genaue Differenzierung und das Staging von HCC und ICC, also auch ein Therapieansprechen ermoeglicht. In diesem Artikel werden moderne, multiparametrische bildgebende Verfahren diskutiert, mit denen beide Tumoren sicher und zuverlaessig diagnostiziert werden koennen. Die kontrastverstaerkte MRT mit Verwendung hepatozytenspezifischer Kontrastmittel stellt derzeit das treffsicherste nichtinvasive Verfahren zur Diagnostik und Therapieevalution von HCC und ICC dar. (orig.)

  18. Completion Report for MRT 3243 TLCC Clusters in Production at LLNL

    Energy Technology Data Exchange (ETDEWEB)

    Cupps, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2009-01-12

    This report provides documentation and evidence for the completion of the deployment of LLNL’s Tri-Lab Capacity Computing (TLCC) clusters juno and eos on the classified network at LLNL. The deployment of these clusters is an L2 Milestone in the ASC FY09-10 Implementation Plan due at the end of Quarter 1 in FY09.

  19. MRT of scaphoid pseudo-arthrosis using Gd-DTPA. Staging and clinical correlation

    International Nuclear Information System (INIS)

    Vogl, T.J.; Beutel, F.; Wilhelm, K.; Tempka, A.; Schedel, H.; Haas, R.; Felix, R.

    1994-01-01

    During a period of two years, 134 patients with pseudo-arthrosis of the scaphoid were examined by conventional radiography and by MRI in the course of a prospective study. The aim of the study was to define radiological staging using contrast enhanced MRI in order to improve the prognostic criteria. All MRI examinations were carried out with a 1.5 Tesla scanner (SP63) using a surface coil and T 1 weighted spin echo sequences in sagittal and frontal projection and frontal FLASH T 2 -sequences and axial spin echo T 2 sequences. The T 1 weighted SE sequences in frontal projection were carried out before and after iv contrast (0.1 mmol Gd-DTPA/kg KG). All sequences were compared with conventional radiographs and the operative findings. Eight patients in stage 0 showed high signal intensity of both fragments in T 1 weighted SE sequences and at surgery there was good vascularisation. In 22 cases there was reduced signal intensity in at least one fragment (stage I). 45 patients with scaphoid pseudo-arthrosis showed complete signal loss but marked contrast uptake with still vital nuclei at surgery (stage II). In 22 patients, there was no increase in signal intensity after contrast and complete loss of vitality of the fragments at surgery. Staging was not possible in 37 patients because of previous operative intervention. The use of contrast enhanced MRI provides additional information compared with conventional radiography or plain MRI. (orig.) [de

  20. MRT measurements of the CSF spaces in HIV associated cerebral atrophy

    International Nuclear Information System (INIS)

    Handwerker, M.; Krahe, T.; Klinker, H.; Schindler, R.

    1992-01-01

    The CSF volume of 45 patients with HIV infection was measured at various clinical stages and the results compared with 24 normals. 60% of all patients showed increased CSF spaces as an indication of cerebral atrophy. Serial measurements were particularly valuable during the early stages of atrophy since there is marked variation in the normal CSF volume. Conventional measurements, with the exception of the width of the third ventricle, were much less sensitive than these quantitative measurements. Classification of HIF infection according to the clinical stage was useful since CSF volume and volume increase correlated with the stage of HIV infection. (orig.) [de

  1. [Fat-suppressing STIR sequences with and without contrast media in the MRT of ENT tumors].

    Science.gov (United States)

    Brüning, R; Heuck, A; Naegele, M; Seelos, K; Vahlensieck, M; Reiser, M

    1994-05-01

    Fat-suppressed STIR (short TI inversion recovery) sequences were compared to plain and contrast-enhanced T1-weighted SE sequences of head and neck tumors. 19 patients underwent MR imaging on a 0.5 Telsa system (T5-II, Philips). STIR imaging parameters: TR/TE = 1000/20 ms, inversion pulse 100 ms. All films were read by four radiologists. The image quality was graded: score from 0 to 5, by means that grade 5 = optimal quality. Sensitivity was 89% in STIR, 96% in SE sequences. Tumor delineation was graded good in the enhanced T1-weighted and enhanced fat suppression images. The unenhanced imaging was superior in STIR (STIR/T1 = 2.8/2.43). The tumor contrast was best in contrast enhanced and plain STIR sequences (STIR contrast = 3.41), and in the contrast enhanced T1-weighted SE (3.33). STIR almost equaled T1 post-contrast in respect of tumour conspicuity, but the sensitivity was lower. STIR can be a supplement to SE, but cannot substitute T1 postcontrast. The combined use is expected to have the highest assessment value.

  2. Management of breast lesions detectable only on MRI; Abklaerung ausschliesslich MRT-detektierbarer Mammalaesionen

    Energy Technology Data Exchange (ETDEWEB)

    Siegmann-Luz, K.C.; Bahrs, S.D.; Preibsch, H.; Hattermann, V.; Claussen, C.D. [Universitaetsklinikum Tuebingen (Germany). Abt. Diagnostische und Interventionelle Radiologie

    2014-01-15

    Breast MR imaging has become established as the most sensitive imaging method for diagnosing breast cancer. As a result of the increasing examination volume and improved image quality, the number of breast lesions detected only on MRI and requiring further clarification has risen in recent years. According to the S3-guideline 'Diagnosis, Therapy, and Follow-Up of Breast Cancer' as revised in July 2012, institutions performing breast MRI should provide the option of an MRI-guided intervention for clarification. This review describes the indications, methods and results of MRI-guided interventions for the clarification of breast lesions only visible on MRI. Recent guidelines and study results are also addressed and alternative methods and pitfalls are presented. (orig.)

  3. Removal, Separation, and Recovery of Heavy Metals from Industrial Wastestreams Using Molecular Recognition Technology (MRT)

    Science.gov (United States)

    2003-01-01

    15,210 Filter Cake/ Brine Storage $5,000 Belt Filter Press $117,000 Pre-Treatment Debris Removal $20,000 Post-Treatment Sand Filters $30,000...ref. 5) investigated 1) ion exchange/ electrolysis and 2) ion exchange/electrodialysis as potential chromium recovery/recycle systems. For the first...system, ion exchange/ electrolysis used both cationic and anionic columns for the Cr (VI) and Cr (III) ions, respectively, with electrolysis to recover

  4. Functional MRI and neurophysiological aspects of obesity; Funktionelle MRT und neurophysiologische Aspekte der Adipositas

    Energy Technology Data Exchange (ETDEWEB)

    Sztrokay, A.; Reiser, M.; Meindl, T. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Gutyrchik, E. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Medizinische Psychologie, Muenchen (Germany)

    2011-05-15

    Functional magnetic resonance imaging studies have revealed that metabolic signals and food stimuli activate the mesocorticolimbic neural network involved in processing the reward system. Activation is influenced by obesity and hunger and many recent brain imaging studies have detected that food and drug stimuli activate many of the same reward circuits. These findings have implications for obesity prevention and therapy. Educational efforts need to be directed towards those at increased risk of becoming obese and the food industry has to be involved in providing and promoting healthier food options. Given that visual food stimuli are potent triggers of desire, seductive advertising of high calorie foods directed towards children should be curtailed. The application of non-invasive brain imaging methodologies to the study of hedonic and homeostatic eating behavior represents a novel and important experimental approach. Further advances in imaging technology and improved experimental designs will provide new and important insights into human ingestive behavior that may lead to new developments in behavioral and pharmacological therapies. (orig.) [German] Bildgebende Studien zeigen, dass Nahrungsreize und metabolische Stimuli das mesokortikolimbische System und somit das Belohnungssystem aktivieren. Die Aktivierung dieses Systems wird sowohl von Hunger als auch Uebergewicht beeinflusst. In bildgebenden Studien wurde nachgewiesen, dass Reize in Form von Essen aehnlich wie Suchtmittel den Belohnungskreislauf aktivieren. Diese Erkenntnis hat Auswirkungen auf die Praevention und Therapie der Adipositas. Die Nahrungsmittelindustrie ist gefordert, gesuenderes Essen zu produzieren und entsprechend zu bewerben. Vor dem Hintergrund, dass die visuelle Stimulation durch Nahrungsmittel ein potenzieller Trigger fuer das Verlangen nach Essen ist, sollte die direkt auf Kinder ausgerichtete Bewerbung hochkalorischer Nahrungsmittel reduziert werden. Die Anwendung nichtinvasiver bildgebender Verfahren fuer die Erforschung von gesundem, homoeostatischem und im Gegensatz dazu hedonischem Essensverhalten repraesentiert einen neuen und wichtigen wissenschaftlichen Ansatz. Weitere Fortschritte auf dem Gebiet der bildgebenden Verfahren und eine Verbesserung des experimentellen Designs koennen neue und bedeutende Erkenntnisse hinsichtlich des menschlichen Essverhaltens liefern. Diese koennten zu neuen Entwicklungen in der Pharmako- und Verhaltenstherapie der Adipositas fuehren. (orig.)

  5. MRT letter: Contrast-enhanced computed tomographic imaging of soft callus formation in fracture healing.

    Science.gov (United States)

    Hayward, Lauren Nicole Miller; de Bakker, Chantal Marie-Jeanne; Lusic, Hrvoje; Gerstenfeld, Louis Charles; Grinstaff, Mark W; Morgan, Elise Feng-I

    2012-01-01

    Formation of a cartilaginous soft callus at the site of a bone fracture is a pivotal stage in the healing process. Noninvasive, or even nondestructive, imaging of soft callus formation can be an important tool in experimental and pre-clinical studies of fracture repair. However, the low X-ray attenuation of cartilage renders the soft callus nearly invisible in radiographs. This study utilized a recently developed, cationic, iodinated contrast agent in conjunction with micro-computed tomography to identify cartilage in fracture calluses in the femora of C57BL/6J and C3H/HeJ mice. Fracture calluses were scanned before and after incubation in the contrast agent. The set of pre-incubation images was registered against and then subtracted from the set of post-incubation images, resulting in a three-dimensional map of the locations of cartilage in the callus, as labeled by the contrast agent. This map was then compared to histology from a previous study. The results showed that the locations where the contrast agent collected in relatively high concentrations were similar to those of the cartilage. The contrast agent also identified a significant difference between the two strains of mice in the percentage of the callus occupied by cartilage, indicating that this method of contrast-enhanced computed tomography may be an effective technique for nondestructive, early evaluation of fracture healing. Copyright © 2011 Wiley Periodicals, Inc.

  6. NMR of the rotator cuff. An update; MRT der Rotatorenmanschette. Ein Update

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, Karl-Friedrich; Maehringer-Kunz, Aline [Universitaetsmedizin Mainz (Germany). Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie

    2016-03-15

    The rotator cuff consists of the tendons of the supscapularis, supraspinatus, infraspinatus and teres minor muscles. This group of muscles performs multiple functions and is often stressed during various activities. This explains, why rotator cuff disease is common and the most often cause of shoulder pain and dysfunction in adults. MR imaging still is the most important imaging modality in assessment of rotator cuff disease. It enables the radiologist to make an accurate diagnosis, the basis for an appropriate management. In this article, current concepts with regard to anatomy and imaging diagnosis will be reviewed. The discussion of the complex anatomy is followed by normal and pathologic MR imaging appearances of the rotator cuff including tendinopathy and tearing, and concluding with a review of the postoperative cuff.

  7. Anterior cruciate ligament tears: MRI versus arthroscopy. Vordere Kreuzbandruptur: MRT versus Arthroskopie

    Energy Technology Data Exchange (ETDEWEB)

    Tosch, U.; Felix, R. (Strahlenklinik und Poliklinik, Universitaetsklinik Rudolf Virchow, Berlin (Germany)); Schauwecker, W.; Dreithaler, B. (Chirurgische Klinik und Poliklinik, Universitaetsklinik Rudolf Virchow, Berlin (Germany))

    1992-05-01

    Because of suspected rupture of the anterior cruciate ligament sixteen acute traumatised patients were investigated by MR and arthroscopy. The MR diagnosis of a lesion of the anterior cruciate ligament proved to be correct by arthroscopy in fifteen of sixteen cases. Diagnostic criteria for lesions of the anterior cruciate ligament were: increased signal intensity in T[sub 1]- and T[sub 2] weighted images, increased volume and discontinuity of ligamentous structures. Additional MR findings of meniscal tears were correct in three of four cases laterally and in four of four cases medially. Femoral cartilage lesions were correctly identified by MR in three cases. MR normal findings proved to be correct by arthroscopy in another five cases. (orig.).

  8. NMR imaging of the liver. Diagnostics, differential diagnostics, therapeutic approaches; MRT der Leber. Diagnostik, Differenzialdiagnostik, Therapieansaetze

    Energy Technology Data Exchange (ETDEWEB)

    Fischbach, Frank; Fischbach, Katharina [Universitaetsklinikum Magdeburg A.oe.R. (Germany). Klinik fuer Radiologie und Nuklearmedizin

    2017-03-01

    The book on NMR imaging of the liver covers the following issues: Fundamentals of NMR imaging, T1-weighted imaging; T2-weighted imaging, diffusion-weighted imaging, cavernous hemangioma, focal nodular hyperplasy; hepatocellular adenoma, hepatocellulas carcinoma, cholangiocellular carcinoma, hepatic metastases.

  9. MRt in the recurrent retinal detachment diagnosis after intraocular tamponade media injection: state of the art

    International Nuclear Information System (INIS)

    Manfre, L.; Midiri, M.; Casto, A.; Angileri, T.; Cardinale, A.

    1994-01-01

    Inraocular Silicon (SO), Fluorosilicon (FSO) oil or Perfluorocarbon fluid (PFCL) injection is a new succesfull surgical technique in the treatment detachment. After personal casu istic review, we report our experience in 37 patients, who underwent pars plana vitrectomy with intraocular SO, FSO or PFCL in injection for retinal detachment, monitored with Magnetic Resonance Imaging controls. MRI, showing no significant oil-related artifcats, revealed as a confident, non-invasive imaging modality in evaluating patient undergone tamponade media intraocular injection

  10. Management of intracranial incidental findings on brain MRI; Management intrakranieller Zufallsbefunde in der MRT-Bildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Langner, S.; Buelow, R.; Kirsch, M. [University Medicine Greifswald (Germany). Inst. for Diagnostic Radiology and Neuroradiology; Fleck, S. [University Medicine Greifswald (Germany). Dept. of Neurosurgery; Angermaier, A. [University Medicine Greifswald (Germany). Dept. of Neurology

    2016-12-15

    The wider use of MRI for imaging of the head in both research and clinical practice has led to an increasing number of intracranial incidental findings. Most of these findings have no immediate medical consequences. Nevertheless, knowledge of common intracranial incidental findings and their clinical relevance is necessary to adequately discuss the findings with the patient. Based on the author's experiences from a large population-based study, the most common incidental MR findings in the brain will be presented, discussing their clinical relevance and giving recommendations for management according to the current literature and guidelines.

  11. MRT letter: light sheet based imaging flow cytometry on a microfluidic platform.

    Science.gov (United States)

    Regmi, Raju; Mohan, Kavya; Mondal, Partha P

    2013-11-01

    We propose a light sheet based imaging flow cytometry technique for simultaneous counting and imaging of cells on a microfluidic platform. Light sheet covers the entire microfluidic channel and thus omits the necessity of flow focusing and point scanning based technology. Another advantage lies in the orthogonal detection geometry that totally cuts-off the incident light, thereby substantially reducing the background in the detection. Compared to the existing state-of-art techniques the proposed technique shows marked improvement. Using fluorescently-coated Saccharomyces cerevisiae cells we have recorded cell counting with throughput as high as 2,090 cells/min in the low flow rate regime and were able to image the individual cells on-the-go. Overall, the proposed system is cost-effective and simple in channel geometry with the advantage of efficient counting in operational regime of low laminar flow. This technique may advance the emerging field of microfluidic based cytometry for applications in nanomedicine and point of care diagnostics. Copyright © 2013 Wiley Periodicals, Inc.

  12. Detection and characterization of left Ventricular Thrombi by MRT compared to Transthoracic Echocardiography

    International Nuclear Information System (INIS)

    Bruder, O.; Jochims, M.; Sabin, G.V.; Waltering, K.U.; Hunhold, P.; Narin, B.; Barkhausen, J.

    2005-01-01

    Purpose: Transthoracic echocardiography is the routine diagnostic procedure in assessing patients with left ventricular thrombi, but is limited by the acoustic window and poor contrast between thrombus and adjacent myocardium. This study evaluates the role of cardiac MRI in the detection of left ventricular thrombi in patients with chronic myocardial infarction compared to standard transthoracic echocardiography. Materials and Methods: In 82 patients (55 men and 27 women, age 36 to 79 years, median 59±11 years) who suffered a myocardial infarction more than 6 months earlier, transthoracic echocardiography and MRI were performed. The MRI protocol included steady state cine imaging (true FISP: TR 3.0 ms, TE 1.5 ms, FA 65 ) in standard long and short axis orientation and contrast-enhanced imaging using a 3D IR-FLASH sequence with long inversion time (TR 4 ms; TE 1.43 ms, FA 10 , TI 300 ms) early, and a 2D IR-FLASH sequence with optimized inversion time (TR 8 ms, TE 4.3 ms, FA 20 , TI 180-280 ms) late after administration of gadolinium. Results: Transthoracic echocardiography depicted 12 thrombi. Contrast-enhanced MRI confirmed these 12 thrombi and detected 23 additional thrombi. With the exception of 2 very small apical thrombi only visible on contrast-enhanced MRI images, spherical thrombi were diagnosed by both techiques, whereas only contrast-enhanced MRI was able to visualize mural thrombi. Left ventricular thrombi were more frequently diagnosed in patients with moderate to severe impairment of the left ventricular systolic function, 32/42 (76%), or in patients with left ventricular aneurysms, 21/24 (84%). Conclusion: Contrast-enhanced MRI is mostly superior to transthoracic echocardiography in diagnosing mural left ventricular thrombi in patients who had suffered a myocardial infarction. Intracavitray thrombi are mor frequently found in patients with impaired regional and global left ventricular function. (orig.)

  13. Core decompression in osteonecrosis of the knee. Follow-up and therapy control by MRT

    International Nuclear Information System (INIS)

    Forst, J.; Forst, R.; Heller, K.D.; Adam, G.B.

    1994-01-01

    Clinically suspected spontaneous osteonecrosis of the knee (Ahlbaeck's disease) was confirmed by MR imaging and subsequent histology in 4 male patients with sudden onset of severe knee pain. The first typical radiological sign for osteonecrosis - flattening of the affected femoral condyle - was seen in no case. All patients were treated surgically by extraarticular drilling for core decompression and were delivered from the complained severe knee pain immediately after surgery. The healing process of these early osteonecroses could be confirmed by the normalisation of bone marrow signal in MR imaging (3 to 15 months) follow-up). Core decompression seems to be an effective treatment in early osteonecrosis of femoral condyles. MR imaging is the most sensitive method for early diagnosis of osteonecrosis and for preoperative planning as well as a helpful tool for a non-invasive postoperative follow-up. (orig.) [de

  14. Cardiovascular hybrid imaging using PET/MRI; Kardiovaskulaere Hybridbildgebung mit PET/MRT

    Energy Technology Data Exchange (ETDEWEB)

    Nensa, Felix; Schlosser, Thomas [Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie

    2014-12-15

    The following overview provides a summary of the state of the art and research as well as potential clinical applications of cardiovascular PET/MR imaging. PET/MRI systems have been clinically available for a few years, and their use in cardiac imaging has been successfully demonstrated. At this period in time, some of the technical difficulties that arose at the beginning have been solved; in particular with respect to MRI-based attenuation correction, caution should be exercised with PET quantification. In addition, many promising technical options are still in the developmental stage, such as MRI-based motion correction of PET data resulting from simultaneous MR acquisition, and are not yet available for cardiovascular imaging. On the other hand, PET/MRI has been used to demonstrate significant pathologies such as acute and chronic myocardial infarction, myocarditis or cardiac sarcoidosis; future applications in clinical routine or within studies appear to be possible. In coming years additional studies will have to be performed to prove diagnostic gain at a reasonable cost-benefit ratio before valid conclusions are possible regarding the clinical utility and future of cardiovascular PET/MR imaging.

  15. Metabolic disorders with typical alterations in MRI; Stoffwechselstoerungen mit typischen Veraenderungen im MRT

    Energy Technology Data Exchange (ETDEWEB)

    Warmuth-Metz, M. [Klinikum der Universitaet Wuerzburg, Abteilung fuer Neuroradiologie, Wuerzburg (Germany)

    2010-09-15

    The classification of metabolic disorders according to the etiology is not practical for neuroradiological purposes because the underlying defect does not uniformly transform into morphological characteristics. Therefore typical MR and clinical features of some easily identifiable metabolic disorders are presented. Canavan disease, Pelizaeus-Merzbacher disease, Alexander disease, X-chromosomal adrenoleukodystrophy and adrenomyeloneuropathy, mitochondrial disorders, such as MELAS (mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes) and Leigh syndrome as well as L-2-hydroxyglutaric aciduria are presented. (orig.) [German] Die Einteilung von Stoffwechselstoerungen nach ihrer Aetiologie ist fuer den diagnostischen Neuroradiologen nicht sinnvoll, da sich aus der zugrunde liegenden Stoerung keine Rueckschluesse auf die zu erwartende MR-Morphologie ziehen lassen. Deshalb sollen anhand typischer bildmorphologischer Veraenderungen in Zusammenschau mit den jeweiligen klinischen Charakteristika einige leicht einzuordnende Stoffwechselstoerungen dargestellt werden. Es handelt sich um den Morbus Canavan, Morbus Pelizaeus-Merzbacher, Morbus Alexander, die X-chromosomal vererbte Adrenoleukodystrophie und Adrenomyeloneuropathie, die mitochondrialen Stoerungen MELAS (mitochondriale Enzephalomyopathie, Laktazidose und Stroke-like-Episoden) und Leigh-Syndrom sowie die L-2-Hydroxyglutarazidurie. (orig.)

  16. TOD Versus MRT When Evaluating Thermal Imagers that Exhibit Dynamic Performance

    National Research Council Canada - National Science Library

    Kostrzewa, Joseph; Long, John; Graff, John; Vincent, John D

    2003-01-01

    .... The Triangle Orientation Discrimination (TOD) metric proposed by Bijl and Valeton, because of its short observation window, provides better capability for evaluating sensors that exhibit non-negligible uniformity...

  17. Differential diagnosis of focal lesions of the kidney in CT and MRT

    International Nuclear Information System (INIS)

    Heckmann, M.; Heinrich, M.; Bautz, W.; Uder, M.; Humke, U.

    2008-01-01

    The great majority of renal masses are found incidentally as a result of the use of ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI). If ultrasonography is not diagnostic CT or MRI should be initiated to differentiate lesions of the kidney that need surgical intervention from those that do not and from those that need follow-up examinations. Cystic renal masses are characterized by using the Bosniak classification, including category IIF. In solid lesions of the kidney first non-surgical lesions as well as lymphoma, renal infarction and nephritis should be excluded. Identifying fatty components in renal lesions is very important because in angiomyolipoma they are almost always present. CT and MRI are excellent for tumor detection. Careful evaluation of imaging finding combined with the patient's history should assist the radiologist in making the proper diagnosis or recommending the appropriate treatment in most cases. This article provides a review about renal masses, the imaging methods for their evaluation and their characteristic features at CT and MR imaging. Different lesions are demonstrated like xantogranulomatous pyelonephritis, acute pyelonephritis, renal infarction, lymphoma, angiomyolipoma, renal oncocytoma, cystic lesion and polycystic disease the kidney, echinococcosis, renal cystadenoma, metastases, renal cell carcinoma (RCC), and multiple bilateral RCC in patients with Hippel-Lindau-Syndrome. This article should help to differentiate complex cystic lesions of the kidney by using the Bosniak-classification, especially Bosniak Category IIF. Solid masses should be characterized and the major question to be answered is whether the mass represents a surgical or nonsurgical lesion or if follow-up studies are necessary. (orig.)

  18. Imaging of postarthroscopic complications after knee injuries; Bildgebung postarthroskopischer Komplikationen nach Knieverletzungen

    Energy Technology Data Exchange (ETDEWEB)

    Schueller-Weidekamm, C. [Medizinische Universitaet Wien, Abteilung fuer Neuroradiologie und muskuloskelettale Radiologie, Klinik fuer Radiodiagnostik, Wien (Austria); Skrbensky, G. von [Medizinische Universitaet Wien, Klinik fuer Orthopaedie, Wien (Austria)

    2012-11-15

    The most common joint injuries in professional and recreational sports participants and also in the total population are knee injuries. Arthroscopy is indicated if this modality will improve the patient outcome and potential long-term complications can be avoided. Although uncommon, complications following arthroscopy are mostly evaluated by magnetic resonance imaging (MRI). For planning further therapy strategies following postarthroscopic complications, e.g. if anterior cruciate ligament (ACL) reconstruction is required, digital radiographs and computed tomography (CT) are helpful. This article provides an overview of the different procedures for surgical treatment which are a prerequisite for the analysis of postarthroscopic images. In addition typical complications after treatment of meniscal and chondral injuries as well as after ACL reconstruction are described and typical signs in MRI, radiography and CT are explained in detail. (orig.) [German] Kniegelenkverletzungen sind nicht nur bei Profisportlern, sondern auch in der Gesamtbevoelkerung die haeufigsten Gelenkverletzungen. Die Indikation zur arthroskopischen Operation wird gestellt, wenn im Vergleich zur konservativen Therapie ein besseres Ergebnis postarthroskopisch zu erwarten ist und potenzielle Spaetkomplikationen verhindert werden koennten. Die selten aber dennoch auftretenden postarthroskopischen Komplikationen werden zumeist mit der Magnetresonanztomographie (MRT) abgeklaert. Zur weiteren Therapieplanung nach Komplikationen, z. B. wenn eine Kreuzbandrevision notwendig ist, sind die digitale Projektionsradiographie und die Computertomographie (CT) hilfreich. Dieser Artikel bietet eine kurze Uebersicht ueber die unterschiedlichen Operationstechniken, die eine Voraussetzung fuer das Verstaendnis der bildgebenden postoperativen Veraenderungen sind. Weiter wird auf die haeufigsten Komplikationen nach Meniskus- und Knorpeloperationen sowie nach vorderer Kreuzbandrekonstruktion und den damit

  19. Clinical or radiological diagnosis of impingement; Klinische oder radiologische Diagnose des Impingements

    Energy Technology Data Exchange (ETDEWEB)

    Kloth, J.K.; Weber, M.A. [Universitaetsklinikum Heidelberg, Klinik fuer diagnostische und interventionelle Radiologie, Heidelberg (Germany); Zeifang, F. [Universitaetsklinikum Heidelberg, Zentrum fuer Orthopaedie, Unfallchirurgie und Paraplegiologie, Heidelberg (Germany)

    2015-03-01

    Shoulder impingement syndrome is a clinically common entity involving trapping of tendons or bursa with typical clinical findings. Important radiological procedures are ultrasound, magnetic resonance imaging (MRI) and MR arthrography. Projection radiography and computed tomography (CT) are ideal to identify bony changes and CT arthrography also serves as an alternative method in cases of contraindications for MRI. These modalities support the clinically suspected diagnosis of impingement syndrome and may identify its cause in primary diagnosis. In addition, effects of impingement are determined by imaging. Therapy decisions are based on a synopsis of radiological and clinical findings. The sensitivity and specificity of these imaging modalities with regard to the diagnostics of a clinically evident impingement syndrome are given in this review article. Orthopedic and trauma surgeons express the suspicion of an impingement syndrome based on patient history and physical examination and radiologists confirm structural changes and damage of intra-articular structures using dedicated imaging techniques. (orig.) [German] Das Impingementsyndrom der Schulter ist ein haeufiges Einklemmungsphaenomen von Sehnen oder Bursen mit typischem klinischem Befund. Wichtige radiologische Verfahren sind Sonographie, MRT und MR-Arthrographie. Projektionsradiographie und CT sind ideal, um knoecherne Veraenderungen aufzuzeigen. Die CT-Arthrographie dient zudem als Ersatzverfahren bei Kontraindikationen fuer die MRT. Diese genannten Modalitaeten koennen in der Primaerdiagnostik die Diagnose eines Impingementsyndroms stuetzen und dessen Ursache aufzeigen. Zudem werden bildgebend Folgen der Einklemmung festgestellt und in Zusammenschau von klinischer Symptomatik und radiologischem Befund Therapieentscheidungen getroffen. Die Sensitivitaet und Spezifitaet der zuvor genannten bildgebenden Verfahren in Bezug auf die diagnostische Aufarbeitung einer klinisch evidenten Impingementsymptomatik

  20. Emission-reduced rapeseed-technology. Project-part 2: expelling of dehulled rapeseed. Final report; Biologisch abbaubare Schmierstoffe - Emissionsarme Rapssaatverarbeitung. Teilvorhaben 2: Trennpressen geschaelter Rapssaat als wissenschaftlich-technische Begleitung. Berichtsteil 1: Schlussbericht als Uebersicht. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, F.H.

    2002-04-01

    Within the technical oil-production the lipids are released by compression and extraction with hexan. Characteristical for rapeseed is the enormous hexan-retention in meal and the delayed release of hexan in the surrounding area. Cause: the lipids, which are locked in the very compact hulls. - The environmental protection integrated in the process of production requires a reduction/avoidance of hexan-emission. The solution: partial detachment of the hulls as an head-end-operation. A process to dehull rapeseed is known since 1979. In the opinion of oil millers dehulled rapeseed is not continuously pressable due to the lack of stability of compressed solid. The aim of the project is to furnish proof of the possibility to press rapeseed. Therefore two experimental ways are necessary: To find out the characteristics of the material under an axial compression and the variation of material- end compression-parameter, research of the screw-press process with a constant stream of compressed material and an ejection of a stable expeller with a variation of the geometric-, process- and material-parameter. Results: (A) dehulled rapeseed (hulls reduced to 1/4) can be pressed in a screw-press (40 kg/h) continuously; after upscaling the press to a semitechnical press an emission-reduced rapeseed-technology is possible. (B) When rapeseed is pressed, friction and therefore a heat-up is clearly reduced; the oil leaves the press with 40 C; a gentle production of oil is possible; user: Teutoburger Oelmuehle, Ibbenbueren. (orig.) [German] Bei technischer Oelgewinnung werden die Lipide durch Pressen und Extrahieren mit Hexan freigesetzt. Spezielles Merkmal von Raps ist die starke Hexanretention im Schrot und verzoegerte Hexanfreisetzung in die Umgebung. Verursacher: die in den kompakten Huellen eingeschlossenen Lipide. - Produktionsintegrierter Umweltschutz erfordert Minderung / Vermeidung der Hexanemissionen. Der Weg: partielles Abtrennen der Huellen als Head-end-Prozessstufe. Ein Schaelverfahren fuer Rapssaat ist seit 1979 bekannt. Bei Oelmuellern gilt geschaelter Raps wegen mangelnder Komprimat-Stabilitaet als kontinuierlich nicht pressbar. - Vorhabensziel ist der Nachweis der kontinuierlichen Pressbarkeit von Schaelraps. - Erforderlich sind zwei experimentelle Arbeitswege: (1) Ermittlung der Merkmale unter axialer Kompression bei Variation der Material- und Kompressions-Parameter, (2) Studium der Seiher-Schneckenpresse bei konstantem Komprimatstrom und Auswurf eines stabilen Schilfers bei Variation der Geometrie-, Betriebs- und Material-Parameter. - Ergebnisse: (A) Schaelraps (Huellen reduziert auf 1/4) ist auf einer Schneckenpresse (40 kg/h) kontinuierlich pressbar; nach Upscaling der Presse in den (halb-)technischen Massstab ist emissionsarme Rapssaatverarbeitung moeglich. (B) Bei Schaelrapspressung ist Reibung und folglich Erwaermung deutlich verringert; das Produktoel verlaesst die Presse mit 40 C; schonende Oelgewinnung ist moeglich. Anwendung: Teutoburger Oelmuehle, Ibbenbueren. (orig.)

  1. Neuroradiological aspects of multiple sclerosis; Neuroradiologische Aspekte bei Encephalitis disseminata

    Energy Technology Data Exchange (ETDEWEB)

    Reiche, W.; Reith, W. [Universitaet des Saarlandes, Homburg/Saar (Germany). Abt. fuer Neuroradiologie; Merkelbach, S. [Universitaet des Saarlandes, Homburg/Saar (Germany). Neurologische Klinik

    2000-11-01

    in normal appearing white matter. (orig.) [German] Die Magnetresonanztomographie (MRT) hat sich zu einer der wichtigsten Untersuchungsmethoden bei Encephalitis disseminata (ED) entwickelt. Die MRT ist sehr sensitiv im Nachweis von ED-Laesionen, jedoch ist ihre Spezifitaet begrenzt. Ziel der vorliegenden Uebersicht ist, die MRT-Charakteristika von ED-Laesionen aufzuzeigen, Empfehlungen fuer standardisierte MRT-Untersuchungsprotokolle fuer die radiologische Routinediagnostik abzuleiten und neue MRT-Entwicklungen zu diskutieren. In der akuten Entzuendungsphase mit Blut-Hirn-Schrankenstoerung zeigen ED-Herde eine Gadolinium-DTPA-Aufnahme und sind, bedingt durch ein Oedem, auf T2-gewichteten Aufnahmen hyperintens. Der weitere Verlauf wird in eine Reparations-/Remylinisationsphase, eine Gliosephase und ein Defektstadium eingeteilt. MR-tomographisch stellen sich ED-Herde in der Reparations- und Gliosephase auf T2-gewichteten Scans hyperintens dar. Die chronische ED-Laesion ist neben einer T2-Hyperintensitaet zusaetzlich durch eine T1-Hypointensitaet als Ausdruck eines Axonenverlusts und Defektes gekennzeichnet. ED-Laesionen weisen ein relativ typisches Verteilungsmuster auf. Sie werden periventrikulaer, im Balken und kallososeptalen Uebergang, kortiko-subkortikal und infratentoriell gefunden. Die wichtigsten prognostischen MR-Kriterien, um eine Entwicklung von einem Verdacht auf eine ED zu einer klinisch sicheren ED vorhersagen zu koennen, sind eine Kontrastmittelaufnahme und eine juxtakortikale Lokalisation, gefolgt von den Parametern periventrikulaere und infratentorielle Lage. (orig.)

  2. Environmental behaviour und ecotoxiology of gadolinium-containing MRT contrast media; Umweltverhalten und Oekotoxikologie von gadoliniumhaltigen Magnetresonanztomographie-Kontrastmitteln

    Energy Technology Data Exchange (ETDEWEB)

    Neubert, Claudia

    2008-07-08

    Magnetic resonance imaging (MRI) is an essential tool in noninvasive diagnostics. In order to improve the sensitivity and specificity of diagnoses, several contrast enhancing agents have been developed in the last few decades by various pharmaceutical manufacturers. Gadolinium (Gd), a lanthanide, is the most widely used metal in MRI contrast agents. Its ion has paramagnetic properties (seven unpaired electrons) and a very long electronic relaxation time. Due to the toxicity of free Gd, clinical use is only possible in a complexed form. Commonly used chelating agents are polyamino-polycarboxylic ligands such as DTPA. Due to the exceptional stability of these highly hydrophilic chelates and the lack of human metabolism, the contrast media are quantitatively excreted unchanged after the administration, and are subsequently emitted into the aquatic environment. Several studies have shown notable increases in Gd concentrations in surface or groundwaters receiving sewage effluents, an observation which has been termed ''Gd anomaly''. The Gd anomaly results from the use of MRI contrast agents for which the most significant entry route is the effluent from wastewater treatment works. Relatively little information on the aquatic toxicity of Gd or Gd-chelates has been published up to 2006. Therefore, in a first step, the acute aquatic toxicity of several MRI contrast agents was investigated in fish, daphnia and algae at high concentrations. Furthermore, chronic toxicity tests on fish and daphnia were conducted. The results showed that contrast enhancing agents containing Gd have no toxic effects on the tested organisms at concentrations being of relevance to the environment. At high concentrations growth inhibition of green algae was observed. The environmental fate and the biological degradation of the contrast media was studied in a model wastewater treatment plant and in aquatic sediment systems. The test compounds were neither biodegradable in the treatment plants nor in the sediment. Additionally, the contrast agents did not accumulate in the sediment. Flocculation with FeCl{sub 3} caused a loss of stability of the Gd-complexes. In a study on the bioaccumulation of the contrast agents marginal concentrations of Gd were detected in fish. To further investigate the toxic potential and the environmental fate of free Gd, studies on the aquatic toxicity, the bioaccumulation potential and the distribution in aquatic sediment systems were performed with GdCl{sub 3} x 6 H{sub 2}O and GdCl{sub 3} x H{sub 2}O, respectively. Gd caused adverse effects in daphnia and algae but was not toxic to fish. Accumulation was observed in fish and sediment. Furthermore, the little water solubility of the lanthanide in natural water was confirmed. (orig.)

  3. Bowel imaging: a reassessment. Pt. 2. CT and MRI; Bildgebende Diagnostik des Darms - eine Neubewertung. T. 2. CT und MRT

    Energy Technology Data Exchange (ETDEWEB)

    Hohl, C.; Muehlenbruch, G.; Schmidt, T.; Guenther, R.W. [Universitaetsklinikum RWTH Aachen (Germany). Klinik fuer Radiologische Diagnostik; Haage, P. [Universitaetsklinik Witten/Herdecke (Germany). HELIOS Klinikum Wuppertal, Klinik fuer Diagnostische und Interventionelle Radiologie

    2007-07-15

    This is the second part of a review of bowel imaging. While the first part addressed conventional X-ray techniques and ultrasonography, the second part discusses the diagnostic features of computed tomography (CT) and magnetic resonance imaging (MRI) including virtual colonography and PET-CT in the diagnosis of bowel disorders. Indications, performance and the diagnostic impact of the different methods are presented and discussed in the context of competitive methods such as (capsule-)endoscopy. (orig.)

  4. fMRI and DTI in delayed development of number processing; fMRT und DTI bei Entwicklungsverzoegerung der Zahlenverarbeitung

    Energy Technology Data Exchange (ETDEWEB)

    Krick, C.M.; Neuhaus, A.; Klewin, C.; Woerner, T.; Kreis, S.; Reith, W. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany)

    2015-09-15

    The neuronal correlate of the current cultural performance arose from developmental processes that can be observed by functional and anatomical magnetic resonance imaging. The velocity of these maturation processes occurs differently between adolescents, causing implications for both school career and academic performance. Regarding spatial-numerical cognition the myelinization of the superior longitudinal bundle appears to be crucial because this fiber connection intermediates between the linguistic nature of number words and conception of their spatial-numerical magnitude. The neuroscientific observation of anatomical brain maturation and its influence on school-relevant number processing may be helpful for educational purposes as well as for school psychology. (orig.) [German] Das neuronale Fundament unserer Kulturleistungen ist einem Entwicklungsprozess unterworfen, der ueber funktionelle und anatomische Magnetresonanzbildgebung beobachtet werden kann. Diese Reifungsprozesse verlaufen bei verschiedenen Jugendlichen unterschiedlich rasch, sodass sich darueber auch Wechselwirkungen mit der Schullaufbahn und schulischen Leistungen ergeben. Im Fall der raeumlich-numerischen Kognition spielt u. a. die Myelinisierung des Fasciculus longitudinalis superior eine entscheidende Rolle, weil diese Faserverbindung fuer das Vermitteln zwischen sprachlichem Zahlenkode und numerischer Groessenvorstellung relevant ist. Die neurowissenschaftliche Darstellung anatomischer Reifeprozesse und deren Einfluss auf die schulrelevanten Prozesse der Zahlenverarbeitung koennen im Lichte paedagogischer oder schulpsychologischer Ueberlegungen dienlich erscheinen. (orig.)

  5. 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.

  6. 3 telsa MRI: successful results with higher field strengths; 3 Tesla-MRT: Der Erfolg hoeherer Feldstaerken

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, F.; Grosu, D.; Purdy, D.; Salem, K.; Scott, K.T.; Stoeckel, B. [Siemens Medical Solutions, Malvern (United States); Mohr, C. [Siemens Medical Solutions, Erlangen (Germany)

    2004-01-01

    The recent development of 3Telsa MRI (3T MRI) has been fueled by the promise of increased signal-to-noise ratio (SNR). Many are excited about the opportunity to no only use the increased SNR for clearer images, but also the change to exchange it for better resolution or faster scans. These possibilities have caused a rapid increase in the market for 3T MRI, where the faster scanning tips an already advantageous economic outlook in favor of the user. As a result, the global market for 3T has grown from a research only market just a few years ago to an ever-increasing clinically oriented customer base. There are, however, significant obstacles to 3T MRI presented by the physics at higher field strength. For example the T1 relaxation times are prolongued with increasing magnet field strength. Further, the increased RF-energy deposition (ASR), the larger chemical shift and the stronger susceptibility effect have to be considered as challenges. It is critical that one looks at both the advantages and disadvantages of using 3T. While there are many issues to address and a number of different methods for doing so, to properly tackle each of these concerns will take time and effort on the part of researchers and clinicians. The optimization of 3T MRI scanning will have to be combined effort, though much work has already been done. The most active area of work to date has been in neuroimaging. Multiple applications have been explored in addition to clinical anatomical imaging, where resolutions is improved showing structure in the brain never before seen in human MRI.

  7. Cardiac magnetic resonance imaging in patients with congenital heart disease; Kardiale MRT bei Patienten mit angeborenen Herzfehlern

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, Karl-Friedrich [Mainz Univ. Universitaetsmedizin Mainz (Germany). Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie; Kaufmann, Lilly [Mainz Univ. (Germany); Sorantin, Erich [Univ.-Klinik fuer Radiologie, Graz (Austria). Klinische Abt. fuer Kinderradiologie

    2015-06-15

    The prevalence of congenital heart disease (CHD) is around 10 per 1000 live births in Germany. More than 90 % of these patients will survive into adulthood due to improvements in therapy. The classification of CHD may be based according to the anatomic structures involved, to the presence of an intracardiac shunt, the presence of a cyanosis and the intensity of therapy and complexity of the disease. Nearly half of all patients with CHD suffer from an intracardiac shunt, whereas complex cases such as patients with a tetralogy of Fallot or transposition of the great arteries are much more rare. Cardiac magnetic resonance imaging plays an important role in the work-up and follow-up of patients with CHD, especially after infancy and childhood. Depending on the abnormality in question, a multiparametric examination protocol is mandatory. Knowledge of operative procedures and findings of other imaging modalities help to optimize examination and time needed for it.

  8. MR imaging of the knee following cruciate ligament reconstruction and meniscal surgery; MRT des Kniegelenks nach Kreuzband- und Meniskusoperationen

    Energy Technology Data Exchange (ETDEWEB)

    Woertler, K. [Technische Univ. Muenchen, Klinikum rechts der Isar (Germany). Inst. fuer Roentgendiagnostik

    2009-03-15

    Due to the increasing number of surgical procedures performed on the knee, MR imaging of the postoperative knee has gained more and more importance. For the evaluation of anterior cruciate ligament grafts and postoperative menisci, basic knowledge of surgical techniques is essential in order to differentiate normal postoperative findings from transplant failure, retears, and complications. This article reviews technical aspects of MR imaging following knee surgery, basic principles of operative techniques for anterior cruciate ligament reconstruction and therapy of meniscal tears, normal postoperative findings, MR imaging criteria for recurrent lesions, and findings with typical complications. (orig.)

  9. MRT of experimental liver abscesses - comparison of a new blood pool contrast agent with gadolinium-DTPA

    International Nuclear Information System (INIS)

    Dick, A.; Adam, G.; Spuentrup, E.; Prescher, A.; Muehler, A.; Guenther, R.W.

    1996-01-01

    Purpose: In an experimental pyogenic liver abscess model, the signal intensities were compared intraindividually and interindividually after the application of a new blood pool contrast agent, 24-gadolinium-DTPA (diethylenetriamine-pentaacetic acid) cascade polymer, and after the application of gadopentetate dimeglumine. Methods: In 20 rabbits with experimentally induced liver abscesses, the relative signal intensities of the liver, abscess centre, abscess wall and portal vein were assessed before and between 30 seconds and 60 minutes after injection of a 25 μmol/kg dose of gadolinium polymer and of 100 μmol/kg of gadolinium-DTPA, respectively. Measurements were performed at 1.5 Tesla, using a head coil and a Flash-2-D sequence. Results: The interindividual comparison (unpaired T-test, p [de

  10. MRI of injuries of the lateral ankle ligaments; MRT bei Verletzungen der lateralen und angrenzenden Baender des Sprunggelenks

    Energy Technology Data Exchange (ETDEWEB)

    Breitenseher, Martin [Landesklinikum Waldviertel Horn, Horn (Austria). Inst. fuer Radiologie und Interventionelle Radiologie

    2011-09-15

    The most frequent sport injury of the ankle is located in the lateral ankle ligaments. The diagnosis of lateral collateral ankle ligament trauma is based on patient history, clinical examination, and stress radiography, allowing a fair diagnosis for the daily routine. For the direct visualization and precise diagnosis of the lateral ankle ligaments MRI provides the best answer. MRI is used with controlled positioning of the foot, correct angulation of sequenzes, and distinct analysis of MR findings. Sinus tarsi ligaments and ligaments of the distal syndesmosis should be included to the report. In selected patients MRI allows the best evaluation of the extent of the lateral ankle ligaments. MRI is the method of choice for combined osteochondral injuries and soft tissue lesions too. (orig.)

  11. Fielding the magnetically applied pressure-shear technique on the Z accelerator (completion report for MRT 4519).

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, C. Scott; Haill, Thomas A.; Dalton, Devon Gardner; Rovang, Dean Curtis; Lamppa, Derek C.

    2013-09-01

    The recently developed Magnetically Applied Pressure-Shear (MAPS) experimental technique to measure material shear strength at high pressures on magneto-hydrodynamic (MHD) drive pulsed power platforms was fielded on August 16, 2013 on shot Z2544 utilizing hardware set A0283A. Several technical and engineering challenges were overcome in the process leading to the attempt to measure the dynamic strength of NNSA Ta at 50 GPa. The MAPS technique relies on the ability to apply an external magnetic field properly aligned and time correlated with the MHD pulse. The load design had to be modified to accommodate the external field coils and additional support was required to manage stresses from the pulsed magnets. Further, this represents the first time transverse velocity interferometry has been applied to diagnose a shot at Z. All subsystems performed well with only minor issues related to the new feed design which can be easily addressed by modifying the current pulse shape. Despite the success of each new component, the experiment failed to measure strength in the samples due to spallation failure, most likely in the diamond anvils. To address this issue, hydrocode simulations are being used to evaluate a modified design using LiF windows to minimize tension in the diamond and prevent spall. Another option to eliminate the diamond material from the experiment is also being investigated.

  12. Sudeck's atrophy - MRI as a new diagnostic procedure. Morbus Sudeck - MRT als neues diagnostisches Verfahren

    Energy Technology Data Exchange (ETDEWEB)

    Schimmerl, S.; Imhof, H. (Vienna Univ. (Austria). MR-Institut); Schurawitzki, H.; Canigiani, G.; Kramer, J. (Vienna Univ. (Austria). Klinik fuer Radiodiagnostik Ludwig-Boltzmann-Institut fuer Radiologisch-Physikalische Tumordiagnostik, Vienna (Austria)); Fialka, V. (Vienna Univ. (Austria). Klinik fuer Physikalische Medizin)

    1991-06-01

    20 patients with clinical diagnosis of reflex sympathetic dystrophy syndrome (RSDS) and positiv results in radiogram and three-phase radionuclide bone scanning were examined by MR, using T{sub 1}- and T{sub 2}-weighted images before and after Gadolinium-DTPA i.v. Soft tissue and bone signal intensity changes can be classified in our diagnostic-therapeutic scheme and proven by histopathological changes. The differentiation between clinical stages is possible and allows an evalution of course and therapy. (orig./GDG).

  13. MRT letter: Two-photon excitation-based 2pi light-sheet system for nano-lithography.

    Science.gov (United States)

    Mohan, Kavya; Mondal, Partha Pratim

    2015-01-01

    We propose two-photon excitation-based light-sheet technique for nano-lithography. The system consists of 2π-configured cylindrical lens system with a common geometrical focus. Upon superposition, the phase-matched counter-propagating light-sheets result in the generation of identical and equi spaced nano-bump pattern. Study shows a feature size of as small as few tens of nanometers with a inter-bump distance of few hundred nanometers. This technique overcomes some of the limitations of existing nano-lithography techniques, thereby, may pave the way for mass-production of nano-structures. Potential applications can also be found in optical microscopy, plasmonics, and nano-electronics. © 2014 Wiley Periodicals, Inc.

  14. Angiogenesis of cancer of the cervix. Contrast-enhanced dynamic MRT, histological quantification of capillary density and lymph system infiltration

    International Nuclear Information System (INIS)

    Hawighorst, H.; Knoop, M.V.; Zuna, I.; Schoenberg, S.O.; Essig, M.; Hoffmann, U.; Brix, G.; Kaick, G. van; Knapstein, P.G.; Weikel, W.; Schaeffer, U.

    1998-01-01

    Purpose: It was the aim of this project to examine (i) the relationships between contrastenhanced dynamic MR imaging derived characteristics and histologic microvessel density counts - a recognized surrogate of tumor angiogenesis - from tumors in patients with primary or recurrent cancer of the uterine cervix, and (ii) to correlate these parameters with lymphatic involvement (i.e. lymphatic channels) to assess tumorbiological aggressiveness in terms of lymphatic spread. Results: Pharmacokinetic MR imaging derived parameters (A, k 21 ) showed a weak but signifikant (p 21 compared with histologic microvessel density, resulting in a significantly (p [de

  15. Clinical neuroanatomy - cranial MRI and CT. 4. rev. and enl. ed.; Klinische Neuroanatomie - kranielle MRT und CT

    Energy Technology Data Exchange (ETDEWEB)

    Lanfermann, Heinrich; Raab, Peter [Medizinische Hochschule Hannover (MHH) (Germany). Inst. fuer Diagnostische und Interventionelle Neuroradiologie; Kretschmann, Hans-Joachim; Weinrich, Wolfgang

    2015-07-01

    The book on clinical neuroanatomy - cranial MRI and CT covers the following issues: layered imaging diagnostics and reference structures; frontal layer, sagittal layers, transverse layers, brainstem, skull topography and the intracranial spaces and structures, facial skull topography, head-neck topography; neurofunctional systems, neurotransmitter and neuromodulators, surveillance material and techniques.

  16. MRI of the prostate. Recommendations on patient preparation and scanning protocol; MRT der Prostata. Empfehlungen zur Vorbereitung und Durchfuehrung

    Energy Technology Data Exchange (ETDEWEB)

    Franiel, Tobias [University Hospital Jena (Germany). Dept. of Diagnostic and Interventional Radiology; Quentin, Michael; Schimmoeller, Lars [University Hospital Duesseldorf (Germany). Dept. of Diagnostic and Interventional Radiology; Mueller-Lisse, Ullrich Gerd [Munich Univ. (Germany). Dept. of Radiology; Asbach, Patrick [Charite Universitaetsmedizin Berlin (Germany). Dept. of Radiology; Roedel, Stefan [Staedtisches Klinikum Dresden Friedrichstadt (Germany). Radiology; Willinek, Winfried [Bonn Univ. (Germany). Radiology; Hueper, Katja [Hannover Medical School (Germany). Inst. for Diagnostic and Interventional Radiology; Beyersdorff, Dirk [University Hospital Hamburg-Eppendorf, Hamburg (Germany). Dept. of Diagnostic and Interventional Radiology; Roethke, Matthias [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Radiology

    2017-01-15

    The Working Group Uroradiology and Urogenital Diagnosis of the German Roentgen Society has developed uniform recommendations for the preparation and implementation of prostate MRI. In the first part detailed recommendations are given in tabular form regarding 1. anamnestic data before prostate MRI, 2. termination of examinations and preparation of examinations, 3. examination protocol and 4. MRI-guided in-bore biopsy. In the second part, the recommendations are discussed in detail and relevant background information is provided.

  17. Spondylolysis in adolescents: the diagnostic value of MRI; Die Spondylolyse im Stadium der Entstehung: Diagnostischer Beitrag der MRT

    Energy Technology Data Exchange (ETDEWEB)

    Staebler, A.; Steinborn, M.; Matzko, M.; Reiser, M. [Klinikum Grosshadern, Muenchen (Germany). Inst. fuer Radiologische Diagnostik; Paulus, R.; Bosch, R. [Muenchen Univ. (Germany). Orthopaedische Klinik

    2000-01-01

    Purpose: To assess the value of MR imaging in demonstrating ongoing spondylolysis in adolescents. Methods: MRI was performed in 9 juvenile patients (3 female, 6 male aged 8-16 years; mean 12.5 y) with pain during hyperextension. In 6 patients a CT scan and in 5 a plain film was available. Results: In all patients bone marrow edema was found in the pars interarticularis and the pedicle, which was bilateral in 4 patients. In 7/9 cases the L5 vertebra was affected, in 2/9 cases spondylolysis was found in L4. In 3 cases the edema reached the middle third of the vertebral body and a tumor was suspected. In all CT scans a bilateral incomplete or complete cleft in the pars interarticularis was found. In 4/6 CT-scans a sclerosis was seen in the area of the bone marrow edema. Only in 1/5 pain films was there a suspicion for a spondylolysis, four examinations were completely normal. Conclusions: To eliminate underlying causal conditions of spondylolysis and to install specific therapy, early diagnosis is mandatory. MR imaging should be the first and only imaging modality in young patients with low back pain during and after exercise and pain with hyperextension. Bone scans and CT scans should be avoided due to irradiation, plain films usually do not reveal pathological findings in developing spondylolysis. (orig.) [German] Ziel: Darstellung der Wertigkeit der MR-Tomographie in der Diagnostik der Spondylolyse im Stadium der Entstehung. Methoden: 9 sportlich, aktive jugendliche Patienten im Alter von 8-16 Jahren (Durchschnitt 12,5 Jahre) mit Rueckenschmerzen bei der Hyperextension wurden MR-tomographisch untersucht. In 6 Faellen lag eine CT, in 5 Faellen Roentgenaufnahmen vor. Ergebnisse: Bei den 9 Jugendlichen wurden Knochenmarkoedeme in der Pars interarticularis und den Bogenwurzeln nachgewiesen, die in 4 Patienten beidseitig vorhanden waren. In 7/9 Faellen war LWK 5 betroffen, in 2/9 LWK 4. In 3 Faellen reichte das Oedem in die Wirbelkoerper, bei 2 Patienten bestand Verdacht auf einen Tumor. Alle CT-Aufnahmen zeigten beidseits inkomplette oder komplette Spaltbildungen der Pars interarticularis, in 4/6 Faellen bestand eine Sklerose in dem Bereich, der MR-tomographisch ein Knochenmarkoedem aufwies. Nur auf einer von fuenf Roentgenaufnahmen bestand der Verdacht auf eine Spondylolyse. Schlussfolgerung: Um ausloesende Ursachen beseitigen und eine spezifische Therapie durchfuehren zu koennen, ist die moeglichst fruehzeitige Diagnose einer drohenden Spondylolyse erforderlich. Die MR-Tomographie sollte die erste und einzige Untersuchungsmethode sein, wenn jugendliche Patienten nach Belastungen und bei Hyperextension ueber Rueckenschmerzen klagen. Die Skelettszintigraphie und die CT sollten wegen der Anwendung ionisierender Strahlung vermieden werden, Roentgenuebersichtsaufnahmen sind gewoehnlich ohne Befund, wenn eine Spondylolyse im Stadium der Entwicklung vorliegt. (orig.)

  18. Neuroimaging of cerebral vasculitis; Bildgebung zerebraler Vaskulitiden

    Energy Technology Data Exchange (ETDEWEB)

    Wengenroth, M. [Universitaetsklinikum Schleswig-Holstein, Campus Luebeck, Institut fuer Neuroradiologie, Luebeck (Germany); Klinikum der Ludwig-Maximilians-Universitaet, Institut fuer klinische Radiologie, Muenchen (Germany); Saam, T. [Klinikum der Ludwig-Maximilians-Universitaet, Institut fuer klinische Radiologie, Muenchen (Germany); Haehnel, S. [Universitaetsklinikum Heidelberg, Abteilung Neuroradiologie, Heidelberg (Germany)

    2016-01-15

    Cerebral vasculitis can have a variety of origins. Furthermore, there are no vasculitis-specific symptoms or imaging signs and vasculitis of the CNS can mimic many other neurological diseases, which require different treatment approaches. Thus, the clinical and radiological diagnosis of cerebral vasculitis is challenging. Magnetic resonance imaging (MRI) and MR angiography (MRA) should be the radiological imaging methods of choice to assess the degree of parenchymal damage and to detect vessel wall changes. If the results are unclear digital subtraction angiography (DSA) should be pursued in order to also detect changes in medium sized vessels. Vasculitis of small vessels cannot be detected by vascular imaging and requires brain or leptomeningeal biopsy. In this review we present the current diagnostic approach and a variety of imaging findings in cerebral vasculitis and discuss the main radiological differential diagnoses. (orig.) [German] Die zerebrale Vaskulitis kann viele Ursachen haben. Daher ist die klinische und radiologische Diagnose schwierig, auch weil es etliche vaskulitistypische Symptome und MR-Befunde bei anderen Erkrankungen gibt. Die ZNS-Vaskulitis kann zahlreiche andere neurologische Erkrankungen imitieren, die unterschiedlicher Therapie beduerfen. MRT und MR-Angiographie (MRA) sind die Verfahren der Wahl, mit denen die radiologische Diagnostik begonnen werden sollte, um den Parenchymschaden und den Gefaessbefall zu beurteilen. Bei unklaren Befunden kann eine digitale Subtraktionsangiographie (DSA) ergaenzt werden, um auch mittelgrosse Gefaesse beurteilen zu koennen. Der Befall kleiner Gefaesse kann nur bioptisch nachgewiesen werden. In der folgenden Uebersicht stellen wir das diagnostische Herangehen bei zerebraler Vaskulitis vor, praesentieren zahlreiche Befunde und diskutieren die wichtigsten radiologischen Differenzialdiagnosen. (orig.)

  19. 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

  20. MRI of the hand and wrist joint of climbers. Imaging of lesions and overstrain injury. Die MRT von Hand und Handgelenk bei Sportkletterern. Darstellung von Verletzungen und Ueberlastungsfolgen

    Energy Technology Data Exchange (ETDEWEB)

    Heuck, A. (Technische Univ. Muenchen (Germany). Inst. und Poliklinik fuer Strahlentherapie und Radiologische Onkologie); Hochholzer, T.; Keinath, C. (Technische Univ. Muenchen (Germany). Klinik und Poliklinik fuer Sportverletzungen)

    1992-05-01

    The hands and wrists of 20 top-level rock climbers with sports injuries and overstress abnormalities were compared with the hands and wrists of 10 normal volunteers. They were all studied with MR imaging at 1.5 T. The imaging protocol included spin-echo and gradient-echo sequences with 1- to 5-mm-thick contiguous slices in the axial, coronal and/or sagittal planes, depending on the location and nature of the suspected injury. Typical hand and wrist lesions depicted with MRI in climbers consisted of annular ligament tears, lesions of the flexor tendons, tenosynovitis, ganglion cysts, joint effusion and functional carpal tunnel syndrome. The MRI findings on these abnormalities were compared to normal findings and those with ultrasound and plain films. In addition, hypertrophic changes in the muscles, tendons, ligaments, and bones of top-level rock climbers were assessed morphometrically. MRI proved to be the superior imaging modality in the diagnosis of sports injuries and overstress abnormalities of the hand the wrist in rock-climbing athletes. (orig.).

  1. Bone scintigraphy compared to MRI and ultrasound in the early diagnosis of arthritis; Skelettszintigraphie im Vergleich mit MRT und Sonographie beim Fruehnachweis der Arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Sandrock, D. [Klinikum Chemnitz gGmbH, Klinik fuer Nuklearmedizin, Chemnitz (Germany)

    2006-12-15

    Chronic inflammatory arthritis is recognized specifically by bone erosions, caused by characteristic pannus tissue. In the finger joints dynamic low-Tesla MRI is nearly double but not completely sensitive in the detection of erosions than conventional radiography, sonography takes an intermediate position. Less specific signs of synovitis and tenosynovitis are shown with high sensitivity by both 3(2)-phase bone scintigraphy and ultrasound, MRI is less sensitive in this respect. However, standard situation of inflammation in bone scintigraphy - positive finding in early as well as late phase - is of surprisingly low sensitivity, any singular finding in the early or late phase has to be regarded as positive. Specificity of these singular findings is nevertheless sufficiently high, acute inflammatory joint changes and even erosions are also seen with MRI in obviously healthy persons. Only 2-phase bone scintigraphy is easily able to present a simultaneous survey of all joints of the body. For this reason 2-phase bone scintigraphy is most suitable for exclusion but also for primary diagnosis of disease, specification must be done afterwards by other imaging modalities or by laboratory findings. (orig.)

  2. Experimental early detection of acute mesenteric ischemia with functional MRI (DWI) and parallel imaging; Experimentelle Fruehdiagnostik der akuten mesenterialen Ischaemie mittels diffusionsgewichteter MRT (DWI) und paralleler Bildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, C.A.; Haage, P. [HELIOS Klinikum Wuppertal, Klinikum der Privaten Univ. Witten/Herdecke (Germany). Klinik fuer Diagnostische und Interventionelle Radiologie; Hohl, C. [HELIOS Klinikum Siegburg (Germany). Klinik fuer Diagnostische und Interventionelle Radiologie

    2012-06-15

    Purpose: To evaluate the feasibility of diagnosing in statu nascendi mesenteric ischemia using diffusion-weighted imaging (DWI) in a porcine model. All experiments were approved by the animal care committee at the district administration. Materials and Methods: Mesenteric blood supply was studied in ten healthy female pigs (weight {proportional_to}50 kg) with artificially induced mesenteric ischemia. In the DSA technique a branch of the superior mesenteric artery was embolized with tissue glue or small particles. DWI was performed using a 1.5 T MR scanner before embolization and 30 and 60 minutes after embolization using a 32-channel receiver coil. ADC maps were calculated for all animals. The findings were correlated to angiographic and autoptic findings. The image quality of DWI was assessed by means of SNR measurements and diagnostic impact by CNR measurements. Results: Embolization of the mesenteric branches was technically successful in all cases. DWI of the bowel was feasible with the applied sequences. In all animals, DWI displayed distinct cytotoxic edema as the earliest sign of ischemia thirty minutes after induction of ischemia. Furthermore, DWI yielded a distinct reduction in the water diffusion coefficient in all animals. Variance analysis showed good correlation between CNR measurements and infarction areas. Autoptic findings could confirm the detected infarction areas by DWI. Conclusion: DWI using parallel imaging techniques is feasible for the early detection of acute mesenteric ischemia. The presented DWI results offer encouraging prospects regarding more rapid disease diagnosis. (orig.)

  3. MRT letter: Human bloodstains on antique aboriginal weapons: a guiding low-vacuum SEM study of erythrocytes in experimental samples on ethnographically documented biological raw materials.

    Science.gov (United States)

    Hortolà, Policarp

    2012-08-01

    The aboriginal use of reed and bone as raw materials for knives and daggers, respectively, has been well-documented ethnographically in some geographical areas of Melanesia. Because of the significant role that these weapons played in inter- and intra-ethnic aggression, they can potentially have retained smears from the contact with human blood. To carry out a guiding low-vacuum scanning electron microscopy (SEM) study of specific interest to ethnography, the outsides of a fragment of stalk of giant cane (Arundo donax) and tibial diaphysis of domestic sheep (Ovis aries) were smeared with peripheral human blood. No biological specimen preparation was applied to the samples. After just over 1 month, bloodstain boundaries and their neighboring inner areas were examined via secondary electrons by a variable-pressure SEM (VP-SEM) working in low-vacuum mode. On both substrates, bloodstains exhibited micro-scales. No janocyte (erythrocyte negative replica) was observed in the examined areas. However, erythrocytes were seen crowded together as grain-shaped corpuscles in the smear on reed, and several hecatocytes (moon-like shaped erythrocytes) were evidenced in the smear on bone. The results of this study suggest that a VP-SEM working in low-vacuum mode can be used fruitfully to detect blood remains in medium-sized reed and bone antique aboriginal artifacts. This procedure can prospectively help to ethnographic museum curators and aboriginal-art surveyors as an easy guiding test in the valuation of antique traditional weapons prior to acquisition, when the real use of a piece has been claimed by the supplier. Copyright © 2012 Wiley Periodicals, Inc.

  4. Clinical indications for high-resolution MRI diagnostics of the peripheral nervous system; Klinische Indikationen hochaufloesender MRT-Diagnostik des peripheren Nervensystems

    Energy Technology Data Exchange (ETDEWEB)

    Godel, T. [Universitaetsklinikum Heidelberg, Abteilung fuer Neuroradiologie, Heidelberg (Germany); Weiler, M. [Universitaetsklinikum Heidelberg, Neurologische Klinik, Heidelberg (Germany)

    2017-03-15

    Peripheral neuropathies are common and diagnostically often challenging disorders. Difficulties particularly exist in lesion localization and recognition of complex spatial lesion patterns. Medical history taking, neurological examination, neurophysiological tests and nerve ultrasonography represent the gold standard in the diagnosis of peripheral nerve lesions but have known methodical limitations. The use of 3 Tesla magnetic resonance neurography (MRN) is an additional diagnostic imaging tool recently developed for the high-resolution visualization of long segments of peripheral nerves. Reasonable clinical indications for MRN are exemplarily presented. Using MRN a direct visualization and thus precise localization of focal and non-focal peripheral nerve lesions of various origins can be achieved with high spatial resolution down to the anatomical level of nerve fascicles. Using MRN large anatomical areas of the peripheral nervous system (PNS) can be covered in a single examination session, spatial nerve lesion patterns can be evaluated and the underlying causes can often be detected. The MRN is a valuable supplement to the diagnostic work-up of the PNS, especially in cases that cannot be clarified with standard diagnostic methods. Evaluation of the spatial nerve lesion pattern gives additional information on the origin of the underlying disease. Reasonable indications for MRN are the assessment of proximal nerve structures including the brachial and lumbosacral nerve plexi, the clarification of inconclusive diagnostic results, preoperative, postoperative and posttraumatic assessments, the identification of fascicular nerve lesions and the differential diagnosis of an alleged somatoform disorder. (orig.) [German] Periphere Neuropathien sind haeufige und diagnostisch mitunter anspruchsvolle Erkrankungen. Schwierigkeiten bestehen v. a. bei der Laesionslokalisation und Erkennung komplexer Laesionsmuster. Anamnese, klinisch-neurologische Untersuchung, elektrophysiologische Funktionsdiagnostik und Nervensonographie stellen den bisherigen Goldstandard der Diagnostik peripherer Nervenlaesionen dar, haben aber methodisch bedingte Limitationen. Mit der 3 Tesla Magnetresonanzneurographie (MRN) steht seit einigen Jahren ein zusaetzliches bildgebendes Verfahren zur hochaufloesenden und langstreckigen Darstellung peripherer Nervenstrukturen zur Verfuegung. Sinnvolle klinische Indikationen fuer eine MRN werden exemplarisch vorgestellt. Die MRN kann fokale und nichtfokale Nervenlaesionen verschiedenster Genese bis auf Faszikelniveau genau direkt visualisieren und damit praezise lokalisieren. Mithilfe der MRN koennen in einem Untersuchungsgang weitraeumige Regionen des peripheren Nervensystems (PNS) erfasst, raeumliche Nervenlaesionsmuster erkannt und z. T. zugrunde liegende Ursachen aufgedeckt werden. Die MRN stellt eine wertvolle Ergaenzung der Diagnostik des PNS dar, insbesondere in den Faellen, die mit den diagnostischen Standardverfahren nicht eindeutig zu klaeren sind. Anhand des Verteilungsmusters der Laesionen sind Rueckschluesse auf die Genese der Erkrankung moeglich. Sinnvolle Indikationen fuer eine MRN sind die Beurteilung proximaler Nervenstrukturen, insbesondere der Arm- und Beinplexus sowie die Abklaerung bei inkonklusiven Vorbefunden, vor Operationen, nach Traumata oder unzufrieden stellenden Operationsergebnissen, zudem die Identifizierung faszikulaerer Nervenlaesionen und die Differenzialdiagnose einer vermeintlich ''somatoformen Stoerung''. (orig.)

  5. Pharmacokinetic analysis of Gd-DTPA enhancement in dynamic MR of breast carcinoma. Pharmakokinetische Analyse der Gd-DTPA-Anreicherung in der MRT beim Mammakarzinom

    Energy Technology Data Exchange (ETDEWEB)

    Hess, T. (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie); Knopp, M.V. (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie); Hoffmann, U. (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie); Brix, G. (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie); Junkermann, H. (Heidelberg Univ. (Germany). Abteilung fuer Gynaekologische Radiologie); Zuna, I. (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie); Fournier, D. von (Heidelberg Univ. (Germany). Abteilung fuer Gynaekologische Radiologie); Kaick, G. van (Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie)

    1994-06-01

    Dynamic Gd-DTPA enhanced MR of the breast was performed in one single slice in 27 patients with suspicious nodular lesions. The results could be histologically verified in all cases. A rapid spin-echo sequence with a time resolution of 8.75 s was used for the dynamic examination. The signal changes were analysed using a pharmacokinetic model which allowed parametrization of the contrast enhancement and transformation of the data into colour coded parameter images. The parameters allowed reliable distinction of 9 benign from 18 malignant lesions (p<0.05 for ''amplitude'', p<0.001 for ''k[sub 21]''). One fibroadenoma could not be distinguished from the carcinomas. Lymph node metastases and the pharmacokinetic parameter amplitude correlated significantly (p<0.05). (orig.)

  6. Qualitative risk analysis in the process of treatment in radiation oncology for the steps performed by the technician/technologist in intensity modulated radiotherapy (lMRT)

    International Nuclear Information System (INIS)

    Teixeira, Flavia C.S.; Faria, Alessandra L.; Pereira, Danielle P.S.; Silva, Fabiana M.I.

    2013-01-01

    The efficacy of radiation therapy is to eradicate the tumor while preserving the integrity of normal tissues. Technological advances have allowed to develop techniques capable of modulating doses delivered to the target volume, providing more effective treatments. However, the operational complexity of these techniques makes the benefits offered are directly proportional to the chances of occurrences of serious errors. The objective of this work is to analyze the steps performed by the technician/technologist in Intensity Modulated Radiotherapy (IMRT), to detect possible errors in order to determine ways to mitigate them. After literature regarding errors in the radiation therapy, a prospective analysis was performed in the first half of 2012 in a radiation clinic located in the city of Rio de Janeiro, in which 11 technicians/technologists contributed to the survey data analysis. The method of risk analysis Failure Mode and Effects Analysis was used for prospective analysis of accidents/incidents, with respect to a qualitative assessment . The method allowed mapping 16 steps performed by technicians/technologists in the treatments with IMRT, identifying possible failures and their causes allowing to find ways to avoid possible errors. This analysis helped to confirm that the qualification and continuing education of technicians/technologists, allied to implement quality assurance programs and a computerized management can make a tool capable of IMRT to achieve the greatest challenge of radiotherapy. (author)

  7. Effect of the positioning of the blades in MRT treatments; Efecto del posicionamiento de las laminas en los tratamientos de IMRT

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz de Zarate Vivanco, R.; Perez Azorin, J. F.; Casquero Ocio, F.; Trueba Garayo, I.

    2013-07-01

    The attenuation of the beams of radiation that cross the treatment table is a verifiable fact that should be incorporated into the planning of the radiation treatments, especially in advanced techniques. (Author)

  8. Normal myelination of the child brain on MRI - a meta-analysis; Die normale Myelinisierung des kindlichen Gehirns in der MRT - eine Metaanalyse

    Energy Technology Data Exchange (ETDEWEB)

    Staudt, M.; Grodd, W. [Tuebingen Univ. (Germany). Abt. fuer Neuroradiologie; Kraegeloh-Mann, I. [Tuebingen Univ. (Germany). Abt. Entwicklungsneurologie und Neuropaediatrie

    2000-10-01

    Purpose: To establish age limits for the assessment of normal myelination of the brain on T{sub 1}-weighted (T{sub 1}w) and T{sub 2}-weighted (T{sub 2}w) images. Method: Comparison of previous publications (Barkovich et al. 1988, Grodd 1993, Hayakawa et al. 1990, Hittmair et al. 1994, Martin et al. 1988/1990/1991, Nakagawa et al. 1998, Staudt et al. 1993/1994, Stricker et al. 1990). Results: Despite technical and methodological differences, these studies principally agreed on the timing of myelination for most regions of the brain. Thus, a common timetable could be established: At 1 month, myelin is visible on both T{sub 1}w and T{sub 2}w in the medulla oblongata, tegmentum pontis, cerebellar peduncles and vermis, quadrigeminal plate, decussation of superior cerebellar peduncles, thalamus, posterior limb of internal capsule, optic radiation, corona radiata. Thereafter, the myelin-typical signal in the different regions of the brain should be present at the following ages (M=months): Anterior limb of internal capsule (2 M: T{sub 1}w; 7 M: T{sub 2}w), splenium of corpus callosum (4 M: T{sub 1}w; 6 M: T{sub 2}w), genu of corpus callosum (6 M: T{sub 1}w; 8 M: T{sub 2}w), centrum semiovale (2 M: T{sub 1}w; 7 M: T{sub 2}w). Branching of myelin into the gyri of the telencephalon (=arborization) appears at the latest at: occipital lobe (5 M: T{sub 1}w; 12 M: T{sub 2}w) and frontal lobe (7 M: T{sub 1}w; 14 M: T{sub 2}w). Conclusion: These extracted age limits can be used for a more reliable assessment of myelination than the time-tables from a single study. (orig.) [German] Ziel: Ermittlung von Altersgrenzen fuer die MR-tomographisch erfassbare Myelinisierung des kindlichen Gehirns in T{sub 1}- und T{sub 2}-gewichteten Aufnahmen (T{sub 1}w, T{sub 2}w). Methode: Vergleich bisher publizierter Zeitangaben (Barkovich et al 1988, Grodd 1993, Hayakawa et al 1990, Hittmair et al 1994, Martin et al 1988/1990/1991, Nakagawa et al 1998, Staudt et al 1993/1994, Stricker et al 1990). Ergebnisse: Trotz deutlicher technischer und methodischer Unterschiede zwischen den einzelnen Studien konnten fuer die meisten Hirnregionen weitgehend uebereinstimmende Zeitangaben gefunden werden. Demnach muessen im Alter von einem Monat bereits folgende Regionen in T{sub 1}w und T{sub 2}w myelintypisches Signal aufweisen: Medulla oblongata, Tegmentum pontis, Pedunculi cerebellares, Vermis cerebelli, Tectum mesencephali, Decussatio pedunculorum cerebelli superiorum, Thalamus, Crus posterius capsulae internae, Radiatio optica, Corona radiata. Danach sollte myelintypisches Signal in den einzelnen Hirnregionen zu folgenden Zeitpunkten erkennbar sein (M=Lebensalter in Monaten): Vorderschenkel der Capsula interna (2 M: T{sub 1}w; 7 M: T{sub 2}w), Splenium corporis callosi (4 M: T{sub 1}w; 6 M: T{sub 2}w), Genu corporis callosi (6 M: T{sub 1}w; 8 M: T{sub 2}w), Centrum semiovale (2 M: T{sub 1}w; 7 M: T{sub 2}w). Im Grosshirn wird eine Aufzweigung des myelintypischen Signals in die einzelnen Gyri (=Arborisation) spaetestens zu folgenden Zeitpunkten sichtbar: Okzipitallappen (5 M: T{sub 1}w; 12 M: T{sub 2}w) und Frontallappen (7 M: T{sub 1}w; 14 M: T{sub 2}w). Schlussfolgerung: Retardierungen der Myelinisierung koennen mit diesen uebereinstimmenden Zeitpunkten aus mehreren Arbeiten mit hoeherer Sicherheit als pathologisch gewertet werden als mit Angaben aus Einzelarbeiten. (orig.)

  9. PI-RADS classification. Structured reporting for MRI of the prostate; PI-RADS-Klassifikation. Strukturiertes Befundungsschema fuer die MRT der Prostata

    Energy Technology Data Exchange (ETDEWEB)

    Roethke, Matthias; Schlemmer, H.P. [Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Abt. fuer Radiologie; Blondin, D. [Universitaetsklinikum Duesseldorf (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie; Franiel, T. [Charite - Universitaetsmedizin Berlin, Campus Mitte (Germany). Inst. fuer Radiologie

    2013-03-15

    Purpose: To flesh out the ESUR guidelines for the standardized interpretation of multiparametric magnetic resonance imaging (mMRI) for the detection of prostate cancer and to present a graphic reporting scheme for improved communication of findings to urologists. Materials and Methods: The ESUR has recently published a structured reporting system for mMRI of the prostate (PI-RADS). This system involves the use of 5-point Likert scales for grading the findings obtained with different MRI techniques. The mMRI includes T2-weighted MRI, diffusion-weighted imaging, dynamic contrast-enhanced MRI, and MR spectroscopy. In a first step, the fundamentals of technical implementation were determined by consensus, taking into account in particular the German-speaking community. Then, representative images were selected by consensus on the basis of examinations of the three institutions. In addition, scoring intervals for an aggregated PI-RADS score were determined in consensus. Results: The multiparametric methods were discussed critically with regard to implementation and the current status. Criteria used for grading mMRI findings with the PI-RADS classification were concretized by succinct examples. Using the consensus table for aggregated scoring in a clinical setting, a diagnosis of suspected prostate cancer should be made if the PI-RADS score is 4 or higher ({>=} 10 points if 3 techniques are used or {>=} 13 points if 4 techniques are used). Finally, a graphic scheme was developed for communicating mMRI prostate findings. Conclusion: Structured reporting according to the ESUR guidelines contributes to quality assurance by standardizing prostate mMRI, and it facilities the communication of findings to urologists. (orig.)

  10. Value of pelvic MRI in the preoperative diagnosis of endometriosis; Wertigkeit der Magnetresonanztomographie (MRT) des Beckens in der praeoperativen Diagnostik der Endometriose

    Energy Technology Data Exchange (ETDEWEB)

    Hauth, E.A.M.; Antoch, G.; Ruehm, S.G.; Forsting, M. [Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie; Boeing, C.; Kimmig, R. [Universitaetsklinikum Essen (Germany). Klinik fuer Frauenheilkunde und Geburtshilfe

    2004-09-01

    Purpose: To determine the value of magnetic resonance imaging (MRI) of the pelvis in the preoperative diagnosis of endometriosis. Materials and Methods: Over a period of 8 months, preoperative MRI of the pelvis were obtained in 13 patients with suspected endometriosis (mean patient age 34.6 years; range 25-47 years). Results: In 9 of 13 patients (69%), the diagnosis of endometriosis was made by MRI and confirmed by laparoscopy in 8 cases. In 2 of 13 patients, endometriotic lesions were detectable by laparoscopy only. In the remaining 2 patients, no endometriosis was visible on MRI or by laparoscopy. MRI was able to visualize a total of 19 endometriotic lesions, with 14 (74%) confirmed by histopathologic examination following laparoscopy. Five of these 19 lesions (26%) visible on MRI were not seen by laparoscopy. Using laparoscopy and subsequent histopathologic examination, 27 endometriotic lesions were diagnosed, with 13 (48%) not seen on the preoperative MRI. Conclusion: MRI and laparoscopy are complementary diagnostic tools that will best document the full extent of endometriosis when combined. MRI can visualize additional lesions inaccessible to laparoscopy. Thus, MRI of the pelvis should used preoperatively for surgical treatment planning. (orig.)

  11. Uterine adenomyosis in infertile patients: MR imaging findings and clinical conclusions; MRT der uterinen Adenomyose bei infertilen Patientinnen: Ergebnisse und klinische Rueckschluesse

    Energy Technology Data Exchange (ETDEWEB)

    Zangos, S.; Eichler, K.; Herzog, C.; Marquardt, F.; Peters, J.; Jacobi, V.; Mack, M.G.; Vogl, T.J. [Inst. fuer Diagnostische und Interventionelle Radiologie, J.W. Goethe-Univ. Frankfurt (Germany); Kissler, S.; Mueller, A.; Siebzehnruebl, E.; Kaufmann, M. [Klinik fuer Gynaekologie und Geburtshilfe, J. W. Goethe-Univ. Frankfurt (Germany); Hamscho, N.; Gruenwald, F. [Klinik fuer Nuklearmedizin, J. W. Goethe-Univ. Frankfurt (Germany)

    2004-11-01

    Purpose: To evaluate the clinical value of magnetic resonance imaging (MRI) of the uterus and the pelvis in infertile female with symptomatic endometriosis for the assessment of uterine morphology and function. Materials and Methods: Forty-one infertile women (mean age: 33.2 years) with symptomatic endometriosis documented by laparoscopy were evaluated with highfield MRI (Sonata, Siemens) using T2- and T1-weighted sequences. In addition, the patients underwent hysterosalpingoscintigraphy (HSSG) for evaluation of the uterotubal transport capacity. Pathologic findings of the uterine junction zone were correlated with the laparoscopic results, clinical symptoms and uterotubal transport capacity. Results: Adenomyosis was diagnosed on T2-weighted MR-images in 35 (85.4%) patients (focal adenomatosis in 26 patients and diffuse adenomatosis in 9). Patients showing signs of adenomyosis tended to be older than patients without adenomyosis (mean age 34.1 years vs. 30.1 years) and showed a longer history of symptomatic endometriosis. A positive transport capacity in HSSG was observed in 73.1% (19/26) of the patients with focal adenomyosis and only 22.2% (2/9) of patients with diffuse adenomyosis. In 83.3% (5/6) of the patients without signs of adenomyosis, a positive uterotubal transport was documented. Conclusion: MRI of the uterus is a helpful diagnostic tool for the diagnosis of adenomyosis and for planning further therapies. Patients with the diagnosis of adenomyosis showed a reduced uterotubal transport capacity that depended on the severity of adenomyotic changes and might be a possible cause of infertility. (orig.)

  12. Functional imaging of submandibular glands: diffusion-weighted echo-planar MRI before and after stimulation; Diffusionsgewichtete MRT zur Funktionsdiagnostik der Glandula submandibularis

    Energy Technology Data Exchange (ETDEWEB)

    Arndt, C.; Cramer, M.C.; Weiss, F.; Kaul, M.G.; Adam, G.; Habermann, C.R. [Zentrum fuer Bildgebende Diagnostik und Intervention, Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Universitaetsklinikum Hamburg-Eppendorf (Germany); Graessner, J. [Siemens Medical Solutions (Germany); Petersen, K. [Zentrum fuer Psychosoziale Medizin, Klinik und Poliklinik fuer Psychiatrie und Psychotherapie, Universitaetsklinikum Hamburg-Eppendorf (Germany); Reitmeier, F.; Jaehne, M. [Kopf und Hautzentrum, Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenheilkunde, Universitaetsklinikum Hamburg Eppendorf (Germany)

    2006-09-15

    Purpose: To investigate the feasibility of diffusion-weighted (DWI) echo-planar imaging (EPI) to depict the submandibular glands and to measure different functional conditions. Materials and Methods: Twenty-seven healthy volunteers were examined. Diffusion weighted sequence was performed prior to stimulation. Exactly 30 seconds after a commercially available lemon juice was given orally, the diffusion weighted sequence was repeated. All examinations were performed by using a 1.5-T superconducting system with a 30 mT/m maximum gradient capability and maximum slew rate of 125 mT/m/sec (Magnetom Symphony, Siemens, Erlangen, Germany). The lower part of the circularly polarized (CP) head coil and a standard two-element CP neck array coil were used. The flexibility of the neck array coil allowed positioning the N1 element (upper part of the coil) right next to the submandibular gland. The axial diffusion-weighted EPI (echo planar imaging) sequence was performed using a matrix of 119 x 128, a field of view of 250 x 250 mm (pixel size 2.1 x 1.95 mm), a section thickness of 5 mm with an interslice gap of 1 mm. The b factors used were 0 sec/mm{sup 2}, 500 sec/mm{sup 2} and 1000 sec/mm{sup 2}. Apparent diffusion coefficient (ADC) maps were digitally transferred to MRIcro (Chris Rorden, University of Nottingham, Great Britain). After detecting the submandibular glands a region of interest (ROI) was placed manually exactly within the boarder of both submandibular glands, excluding the external carotid artery on ADC maps. These procedures were performed on all ADC slices the submandibular glands could be differentiated in before and after oral stimulation. For statistical comparison of results, a student's t-test was performed with an overall two-tailed significance level of p=0.05. Results: The visualization of the submandibular glands using the diffusion-weighted EPI sequence was possible in all of the 27 volunteers. Prior to oral stimulation an ADC of 1.31 x 10{sup -3} mm{sup 2}/sec (95% CI, 1.39 x 10{sup -3} mm{sup 2}/sec, 144. x 10{sup -3} mm{sup 2}/sec) was calculated which increased to 1.41 x 10{sup -3} mm{sup 2}/sec (95% KI, 1.39 x 10{sup -3} mm{sup 2}/sec, 1.44 x 10{sup -3} mm{sup 2}/sec) 30 seconds after stimulation. This increase proved to be significant (p<0.001). Conclusion: Diffusion-weighted echo-planar MR imaging allows non-invasive quantification of functional changes in the submandibular gland. (orig.)

  13. MRI in patients with pacemakers? First global consensus recommendations from radiologists and cardiologists; Mit Schrittmacher ins MRT? Weltweit erste konsentierte Handlungsempfehlung von Radiologen und Kardiologen

    Energy Technology Data Exchange (ETDEWEB)

    Heindel, Walter; Kugel, Harald [University Hospital Muenster (Germany). Dept. of Clinical Radiology

    2017-03-15

    Under the title ''MR Imaging in Patients with Cardiac Pacemakers and Implantable Cardioverter Defibrillators'', this issue of Roefo - simultaneously with the journal of the German Cardiac Society ''Der Kardiologe'' - presents a consensus paper of the German Roentgen Society and the German Cardiac Society [1] [2] that was jointly written by the authors in radiology and cardiology but does not exclusively address cardiac MRI. This publication relates to MR imaging of all regions of the body. In Germany and internationally the number of MRI examinations is increasing: 1,008,944 examinations were performed on patients receiving inpatient treatment in 2005 while 1,767,005 examinations were performed in 2013 (DRG hospitals). This development can be attributed to our aging population as well as to new indications for MRI including: Analyses of tissue composition and function, for example in the liver [3] [4] and the heart [5] [6]; multiparametric analyses of MR perfusion, e.g. in treated brain tumors [7]; new organs such as the lung [8]; dedicated examinations for intervention planning and operation monitoring [9] [10] [11]; as well as MRI-guided interventions [12] [13] [14] [15] [16]. Implants must always be considered in all of these MRI examinations even if the reason for the examination request is not related to an implant. The involvement of cardiology in this case is not based on the medical issue but rather on the type of implant. Expertise in cardiology is required when dealing with cardiac pacemakers (PM) and implantable cardioverter defibrillators (ICD).

  14. Morphologische Veränderung des Beckenbodens und klinisches Outcome nach Resektionsrektopexie bei Beckenbodeninsuffizienz : Eine explorative, deskriptive Studie anhand der dynamischen Beckenboden-MRT

    OpenAIRE

    Busse, Anika

    2013-01-01

    Der Beckenboden und insbesondere die Beckenbodeninsuffizienz mit ihren Folgeerkrankungen wie anale Inkontinenz und Obstipationen sind nach wie vor ein Tabuthema. Aufgrund der steigenden Prävalenz, der damit verbundenen steigenden Kosten für das Gesundheitssystem und aufgrund der deutlichen Beeinflussung der Lebensqualität ist es wichtig effektive diagnostische Möglichkeiten und Therapien zu besitzen. Ziel dieser vorliegenden Studie sollte es somit sein das Outcome nach Resektionsrektopexie be...

  15. Magnetic resonance imaging of the pelvis in patients with polycystic ovary syndrome; Magnetresonanztomografie (MRT) des Beckens bei Patientinnen mit polyzystischem Ovarsyndrom

    Energy Technology Data Exchange (ETDEWEB)

    Hauth, E.A.; Umutlu, L.; Libera, H.; Forsting, M. [Inst. fuer diagnostische und interventionelle Radiologie und Neuroradiologie, Universitaetsklinikum Essen (Germany); Kimmig, R. [Klinik fuer Frauenheilkunde und Geburtshilfe, Universitaetsklinikum Essen (Germany)

    2009-06-15

    Introduction: MRI evaluation of parameters of the ovaries for the diagnosis of polycystic ovaries in patients with polycystic ovary syndrome (PCOS). Materials and methods: an MRI of the pelvis was performed in 51 patients with PCOS and 50 healthy volunteers. The volume and maximum diameter of the bigger ovary, the number of follicles, and the maximum diameter and volume of the biggest follicle of the bigger ovary were determined in relation to patient age and were statistically compared. ROC analysis was performed to evaluate the prognostic quality of the parameters of the ovaries regarding the diagnosis of PCOS. Results: in a cohort aged 21 - 30 a significant difference between patients with PCOS and healthy volunteers was able to be determined for all 5 parameters (p < 0.001). In the cohort aged 31 - 40 neither one of the parameters showed a significant difference. In the group of 21 - 30 year-olds the AUC was significantly different from 0.5 in all parameters. The maximum diameter, the volume and the number of follicles of the bigger ovary presented the highest AUC. The parameters needed to diagnose PCOS in MRI in a group of women aged 21 - 30 are a maximum diameter of an ovary of 30 mm, an ovarian volume of 5.6 cm{sup 3} and at least 12 follicles. In regard to these parameters a diagnostic sensitivity of 90.32%, 90.32% und 80.65% and a specificity of 68.42%, 63.16% und 86.42% can be reached. (orig.)

  16. Magnet discolation - An increasing and serious complication following MRI in patients with chochlear implants; Magnetdiskolation - eine zunehmende und folgenreiche Komplikation nach MRT bei Patienten mit Cochlea Implantat

    Energy Technology Data Exchange (ETDEWEB)

    Hassepass, F.; Staubenau, V.; Arndt, S.; Beck, R.; Grauvogel, T.; Aschendorff, A. [Univ. Medical Center Freiburg (Germany). Dept. of Otorhinolaryngology-Head and Neck Surgery; Bulla, S. [Univ. Medical Center Freiburg (Germany). Dept. of Diagnostic Radiology

    2014-07-15

    Cochlear implantation (CI) represents the gold standard in the treatment of children born deaf and postlingually deafened adults. Initial magnetic resonance imaging (MRI) was contraindicated in CI users. Meanwhile, there are specific recommendations concerning MRI compatibility depending on the type of CI system and the device manufacturer. Some CI systems are even approved for MRI with the internal magnet left in place. The aim of this study was to analyze all magnet revision surgeries in CI patients at one CI center and the relationship to MRI scans over time. Between 2000 and 2013, a total of 2027 CIs were implanted. The number of magnet dislocation (MD) surgeries and their causes was assessed retrospectively. In total 12 cases of MD resulting from an MRI scan (0.59 %) were observed, accounting for 52.2 % of all magnetic revision surgeries. As per the labeling, it was considered safe to leave the internal magnet in place during MRI while following specific manufacturer recommendations: MRI intensity of 1.5 Tesla (T) and compression head bandage during examination. A compression head bandage in a 1.5 T MRI unit does not safely prevent MD and the related serious complications in CI recipients. We recommend a Stenvers view radiograph after MRI with the internal magnet in place for early identification of MD, at least in the case of pain during or after MRI examination. MRI in CI patients should be indicated with restraint and patients should be explicitly informed about the possible risks. Recommendations regarding MRI compatibility and the handling of CI patients issued with MRI for the most common CI systems are summarized.

  17. Physical interactions in MRI. Some rules of thumb for their reduction; Physikalische Wechselwirkungen in der MRT. Einige Daumenregeln zu ihrer Reduktion

    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. [Medizinische Universitaet Wien, Exzellenzzentrum Hochfeld-Magnetresonanz, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria)

    2015-08-15

    Magnetic resonance imaging (MRI) is one of the most powerful and at the same time gentlest clinical imaging techniques at the present time; however, the enormous physical complexity as well as simple inattentiveness (projectile effect) implicate a significant risk potential and place high demands on the MR operator to ensure a safe workflow. A sound knowledge of the potential MR interactions is the foundation for a safe and profitable operation for all parties. The first part of this article deals with the three most important sources of physical interaction, i.e. static magnetic field, gradient and high-frequency (HF) fields. The paper discusses the differences between each type of field with respect to the impact on human beings, the interactions with magnetic and electrically conducting objects/implants and the relevant safety standards. Each section is followed by simple rules of thumb to minimize potentially unwanted physical MRI interactions. (orig.) [German] Die Magnetresonanztomographie ist eines der leistungsfaehigsten und zugleich schonendsten klinischen bildgebenden Verfahren der heutigen Zeit. Allerdings bergen ihre enorme physikalische Komplexitaet, aber auch einfache Unaufmerksamkeiten (''Projektileffekt'') ein signifikantes Risikopotenzial in sich und stellen hohe Anforderungen an die MR-Bediener, um einen sicheren Betrieb zu gewaehrleisten. Ein solides Wissen um die potenziellen MR-Wechselwirkungen ist die Grundlage fuer einen sicheren und fuer alle Seiten gewinnbringenden Betrieb. Der erste Teil der Arbeit behandelt die 3 zentralen Quellen fuer physikalische Wechselwirkungen in der Magnetresonanztomographie (statisches Magnetfeld, geschaltete Gradienten- und HF-Felder). Es werden fuer jede Feldart die Auswirkungen auf den Menschen, Wechselwirkungen mit magnetischen und elektrisch leitenden Objekten/Implantaten und relevante Sicherheitsstandards besprochen. Daran angeschlossen ist jeweils ein Abschnitt mit einfachen ''Daumenregeln'', um potenziell unerwuenschte physikalische MR-Wechselwirkungen zu minimieren. (orig.)

  18. International Working Group-Myeloproliferative Neoplasms Research and Treatment (IWG-MRT) & European Competence Network on Mastocytosis (ECNM) consensus response criteria in advanced systemic mastocytosis

    NARCIS (Netherlands)

    Gotlib, Jason; Pardanani, Animesh; Akin, Cem; Reiter, Andreas; George, Tracy; Hermine, Olivier; Kluin-Nelemans, Hanneke; Hartmann, Karin; Sperr, Wolfgang R.; Brockow, Knut; Schwartz, Lawrence B.; Orfao, Alberto; DeAngelo, Daniel J.; Arock, Michel; Sotlar, Karl; Horny, Hans-Peter; Metcalfe, Dean D.; Escribano, Luis; Verstovsek, Srdan; Tefferi, Ayalew; Valent, Peter

    2013-01-01

    Systemic mastocytosis (SM) is characterized by accumulation of neoplastic mast cells and is classified into indolent and aggressive forms. The latter include aggressive SM (ASM), mast cell leukemia (MCL), and SM associated with a myeloid neoplasm wherein 1 or both disease compartments exhibit

  19. Indications and contraindications for contrast-enhanced MRI and CT during pregnancy; Indikationen und Kontraindikationen kontrastmittelverstaerkter MRT- und CT-Untersuchungen in der Schwangerschaft

    Energy Technology Data Exchange (ETDEWEB)

    Junkermann, H. [Universitaetsfrauenklinik Heidelberg, Sektion Senologische Diagnostik, Heidelberg (Germany)

    2007-09-15

    There are no reports about negative effects on the fetus of the application of gadolinium-containing contrast media to pregnant mothers. Iodine-containing contrast media may lead to a transient hypothyroidism in the newborn. This will be detected with certainty by the neonatal TSH screening. Iodine- or gadolinium-containing contrast media may be used in pregnant women if indispensable. In the gut of breastfed children less than 1% of the recommended pediatric doses of contrast media are found after both types of contrast media have been given to their mothers. Therefore there are no reasons against the use of contrast media during the nursing period. (orig.) [German] Fuer gadoliniumhaltige Kontrastmittel liegen keine Beobachtungen ueber schaedigende Wirkungen auf den Fetus vor. Jodhaltige Kontrastmittel koennen u. U. eine voruebergehende Hypothyreose beim Neugeborenen hervorrufen, die durch das Hypothyreosescreening sicher erkannt wird. Bei strenger Indikationsstellung koennen sowohl jodhaltige als auch gadoliniumhaltige Kontrastmittel in der Schwangerschaft angewendet werden. Bei stillenden Muettern wird bei beiden Arten von Kontrastmitteln weniger als 1% der fuer die Untersuchung von Neugeborenen empfohlenen Dosis im Darm des Saeuglings gefunden, sodass gegen einen Einsatz waehrend der Stillperiode keine Einwaende bestehen. (orig.)

  20. Characterization of an experimental venous thrombus model with MRI, phlebography and histology; Charakterisierung eines experimentellen venoesen Thrombosemodels mittels MRT, Phlebographie und Histologie

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, S.A. [Klinik und Hochschulambulanz fuer Radiologie und Nuklearmedizin, Charite - Universitaetsmedizin Berlin (Germany); Imaging Sciences Dept., Hammersmith Hospital, Faculty of Medicine, Imperial College London (United Kingdom); Schiffler, S.; Gust, R.; Winterhalter, S.; Wolf, K.J. [Klinik und Hochschulambulanz fuer Radiologie und Nuklearmedizin, Charite - Universitaetsmedizin Berlin (Germany); Coupland, S.E. [Institut fuer Pathologie, Charite - Universitaetsmedizin Berlin (Germany)

    2005-03-01

    Introduction: Several magnetic resonance (MR) techniques designed to demonstrate the characteristic signal intensity of blood degeneration products of thrombi have been suggested, but the effect of thrombus organization on the MR display, in particular with regard to its temporal evolution, remains to be determined. It is the purpose of this study to develop a stagnation thrombus model in rabbits and to characterize thrombus at different ages with two (MR) imaging techniques, phlebography and histology. Materials and Methods: Venous stagnation thrombi were induced in the external jugular veins of rabbits using a minimally invasive radiological technique to produce artificial embolic vascular occlusion and hypercoagulability. Twenty-five animals were divided into 5 groups of 5 animals, and each group underwent 1.5 T MR imaging at 1, 3, 5, 7 and 9 days after thrombus induction using a T1-weighted magnetization-prepared rapid gradient-echo sequence (MP-RAGE: TR 10.4 msec, TE 4.0 msec, FA 15 ) and a T2-weighted fast low-angle shot sequence (FLASH: TR 54 msec, TE 18 msec, FA15 ). The thrombus length was measured on the T1-weighted images. Thrombus conspicuity, signal intensity, and heterogeneity on T2* weighted images were described using visual scales. Radiographic venography and histology served as reference methods. Results: Thrombi were successfully induced in all animals. The overall thrombus length decreased from 43{+-}9 (day 1 after induction) to 23{+-}4 mm (day 9). On 3D-reconstructions of the T1-weighted images, the visible portion of the true thrombus length relative to the overall thrombus length was 0.16{+-}0.3 (day 1), 0.24{+-}0.3 (day 3),0.38{+-}0.5 (day 5), 0.06{+-}0.1 (day 7) and 0.00 (day 9). Sixteen of 25 thrombi were detectable with the T2*-weighted technique. The overall thrombus signal intensity decreased with the age of the thrombus from day 1 to day 9. The histological evaluation showed that the rabbit thrombi closely resemble human thrombi morphologically. (orig.)

  1. Arterial spin labelling in imaging of renal diseases and renal allograft pathology; MRT-Perfusionsmessung mit Arterial Spin Labelling. Anwendung fuer die Niere und Transplantatniere

    Energy Technology Data Exchange (ETDEWEB)

    Hueper, Katja; Gutberlet, Marcel [Medizinische Hochschule Hannover (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie; Kuehn, Bernd [Siemens AG/Siemens Healthcare GmbH, Erlangen (Germany)

    2016-06-15

    Arterial Spin Labelling (ASL) is a technique for non-invasive and contrast-free assessment of perfusion with MRI. Renal ASL allows examination of renal pathophysiology, evaluation of the course of renal disease and therapy effects by longitudinal measurements as well as characterization of renal tumors. In this article, techniques of ASL will be explained and challenges of renal ASL will be emphasized. In addition, examples for clinical application of ASL for diagnosis of renal disease and renal allograft pathology will be given.

  2. Striated nephrogram as an incidental finding in MRI examination of children; Streifiges Nephrogramm als Zufallsbefund nach Kontrastmittelgabe bei Kindern in der MRT

    Energy Technology Data Exchange (ETDEWEB)

    Strocka, S.; Sorge, I.; Ritter, L.; Hirsch, F.W. [Leipzig Univ. (Germany). Dept. of Pediatric Radiology

    2016-01-15

    A highly striated contrast pattern of the kidneys occasionally appears in abdominal MRI examinations of children following the administration of gadolinium. As this phenomenon is well known but has not yet been explicitly described in literature, we investigated how frequently and in which clinical context this occurred. 855 abdominal MRI examinations with contrast media of 362 children between 2006 and 2014 were analysed retrospectively. A striated renal parenchyma was found in a total of nine children and eleven examinations (1.3 % of examinations) and did only occur at a field strength of 3 Tesla. Of these children, seven had previously had tumors and chemotherapy. In two children there was no evidence of a previously serious condition with medications or a kidney disease. All of them had a normal renal function. A noticeably striated nephrogram in the later phase of an MRI examination following administration of gadolinium may appear as an incidental finding in examinations at 3 Tesla without pathological relevance.

  3. Qualitative risk analysis in the process of treatment in radiation oncology for the steps performed by the technician/technologist in intensity modulated radiotherapy (lMRT); Analise qualitativa do risco no processo de tratamento em radioterapia para as etapas executadas pelo tecnico/tecnologo na radioterapia de intensidade modulada (lMRT)

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Flavia C.S., E-mail: flavia@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil); Faria, Alessandra L.; Pereira, Danielle P.S.; Silva, Fabiana M.I. [Universidade UNIGRANRIO, Duque de Caxias, RJ (Brazil)

    2013-10-01

    The efficacy of radiation therapy is to eradicate the tumor while preserving the integrity of normal tissues. Technological advances have allowed to develop techniques capable of modulating doses delivered to the target volume, providing more effective treatments. However, the operational complexity of these techniques makes the benefits offered are directly proportional to the chances of occurrences of serious errors. The objective of this work is to analyze the steps performed by the technician/technologist in Intensity Modulated Radiotherapy (IMRT), to detect possible errors in order to determine ways to mitigate them. After literature regarding errors in the radiation therapy, a prospective analysis was performed in the first half of 2012 in a radiation clinic located in the city of Rio de Janeiro, in which 11 technicians/technologists contributed to the survey data analysis. The method of risk analysis Failure Mode and Effects Analysis was used for prospective analysis of accidents/incidents, with respect to a qualitative assessment . The method allowed mapping 16 steps performed by technicians/technologists in the treatments with IMRT, identifying possible failures and their causes allowing to find ways to avoid possible errors. This analysis helped to confirm that the qualification and continuing education of technicians/technologists, allied to implement quality assurance programs and a computerized management can make a tool capable of IMRT to achieve the greatest challenge of radiotherapy. (author)

  4. 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.

  5. Clinical applications of single photon emission tomography in neuromedicine. Pt. 2. Dementia, psychotic disorders, inflammation, trauma; Klinische Anwendungen der Single-Photon-Emissionstomographie in der Neuromedizin. T. 2. Dementielle Erkrankungen, Psychosen, Entzuendungen, Schaedelhirntrauma

    Energy Technology Data Exchange (ETDEWEB)

    Bartenstein, P.; Gruenwald, F.; Kuwert, T.; Tatsch, K.; Sabri, O.; Benkert, O.; Fahlbusch, R.; Gruender, G.; Herholz, K.; Weiller, C. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    2000-12-01

    This article gives in his second part a critical review of the clinical applications of SPECT with perfusion markers and receptor ligands in dementing disorders and psychosis. In addition this review discusses clinical applications of SPECT investigations with perfusion markers in inflammatory diseases of the central nervous system and in brain trauma. (orig.) [German] Die vorliegende Arbeit vermittelt in ihrem zweiten Teil eine kritisch wertende Uebersicht ueber die klinischen Anwendungsmoeglichkeiten von SPECT-Untersuchungen mit Perfusionsmarkern und Rezeptorliganden bei dementiellen Erkrankungen sowie affektiven und schizophrenen Psychosen. Darueber hinaus werden in dieser Uebersicht Anwendungen von SPECT-Untersuchungen mit Perfusionsmarkern bei Fragestellungen im Rahmen von Entzuendungen des zentralen Nervensystems und bei Schaedelhirntraumata diskutiert. (orig.)

  6. Natural gas: Supply safety and Geopolicy of the European Union; Erdgas: EU-Versorgungssicherheit und Geopolitik

    Energy Technology Data Exchange (ETDEWEB)

    Linde, Coby van der [Clingendael International Energy Programme, The Hague (Netherlands)

    2004-12-01

    A presentation of a global overview on gas markets, possible consequences for a long-term supply safety and political options to control possible risks. (GL) [German] Eine Uebersicht der Entwicklungen auf Gasmaerkten weltweit, der moeglichen Konsequenzen fuer die langfristige Versorgungssicherheit Europas sowie der Politikoptionen, um moegliche Risiken zu kontrollieren, wird im Folgenden vorgestellt. (orig.)

  7. Cerebral and spinal MRI examination in patients with clinically isolated syndrome and definite multiple sclerosis; Zerebrale und spinale MRT-Untersuchung bei Patienten mit klinisch isoliertem Syndrom oder gesicherter Multipler Sklerose

    Energy Technology Data Exchange (ETDEWEB)

    Sailer, M.; Fazekas, F.; Gass, A.; Kappos, L.; Radue, E.W.; Rieckmann, P.; Toyka, K.; Wiendl, H.; Bendszus, M. [Neurologische Universitaetsklinik, Otto-von-Guericke Univ., Magdeburg (Germany)

    2008-11-15

    Purpose: magnetic resonance imaging (MRI) has become a valuable tool for diagnosing and monitoring multiple sclerosis (MS). The high sensitivity for the detection of hyperintense lesions in T2-weighted scans contributes substantially to diagnosis. The initial lesion number or lesion volume stands for an increased probability of further accumulation of lesion burden, an earlier conversion to clinically definite MS and progression of disability in the next 5-15 years. This diagnostic and prognostic information gained from MRI early in the disease course lead in 2001 to a revision of the diagnostic criteria. Materials and methods: for the first time MRI criteria were defined in addition to the clinical and paraclinical criteria using the clinical terms for dissemination with respect to space and time. In particular, the defined MRI criteria are based on lesion number and location, the appearance of new lesions and lesion enhancement using contrast agent. Results: reliable detection and description of older and new lesions in the disease course by MRI represents subclinical disease activity which can substitute the clinical confirmation of a relapse leading to an earlier diagnosis. This places importance on the assessment of the subclinical disease activity in sequential MR scans requiring a standardized and reproducible approach to minimize variability despite different MR scanners. (orig.)

  8. Signal/time-relation of benign and malignant lesions in dynamic 2D-MR imaging of the breast. Signalverhalten maligner und benigner Laesionen in der dynamischen 2D-MRT der Mamma

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, U. (Abteilung Roentgendiagnostik 1, Univ. Goettingen (Germany)); Heyden, D. v. (Abteilung Roentgendiagnostik 1, Univ. Goettingen (Germany)); Vosshenrich, R. (Abteilung Roentgendiagnostik 1, Univ. Goettingen (Germany)); Vieweg, I. (Abteilung Roentgendiagnostik 1, Univ. Goettingen (Germany)); Grabbe, E. (Abteilung Roentgendiagnostik 1, Univ. Goettingen (Germany))

    1993-04-01

    In a retrospective study of 400 dynamic MR examinations of the breast the signal/time ratio of 62 histopathologically correlated lesions (19 benign, 42 malignant) was evaluated. Points of evaluations were initial signal enhancement (1st and 2nd minute), post-initial signal apperance (2nd to 5th minute) and signal distribution (homogeneous, marginal). Based on these criteria, a point system was defined to help in the assessment of lesions in dynamic breast-MR imaging. The overall sensitivity of this method was 95.3%, the specificity to 89.5% and the accuracy to 93.5%. Pitfalls resulted in two cases of non-invasive carcinoma and in two patients with fibroadenoma. (orig.)

  9. The whole spectrum of alcohol-related changes in the CNS. Practical MR and CT imaging guidelines for daily clinical use; Alkoholinduzierte ZNS-Veraenderungen in der bildgebenden Diagnostik. Ein CT- und MRT-Leitfaden fuer die klinische Praxis

    Energy Technology Data Exchange (ETDEWEB)

    Keil, V.C.; Greschus, S.; Hadizadeh, D.R.; Schild, H.H. [University Hospital Bonn (Germany). Dept. of Radiology; Schneider, C. [University Hospital Bonn (Germany). Dept. of Neurology

    2015-12-15

    Alcohol addiction is the most common drug addiction. Alcohol passes both the placenta as well as the blood-brain barrier and is in multiple ways neurotoxic. Liver diseases and other systemic alcohol-related diseases cause secondary damage to the CNS. Especially in adolescents, even a single episode of severe alcohol intoxication (''binge drinking'') may result in life-threatening neurological consequences. Alcohol-related brain and spinal cord diseases derive from multiple causes including impairment of the cellular metabolism, often aggravated by hypovitaminosis, altered neurotransmission, myelination and synaptogenesis as well as alterations in gene expression. Modern radiological diagnostics, MRI in particular, can detect the resulting alterations in the CNS with a high sensitivity. Morphological aspects often strongly correlate with clinical symptoms of the patient. It is less commonly known that many diseases considered as ''typically alcohol-related'', such as Wernicke's encephalopathy, are to a large extent not alcohol-induced. Visible CNS alterations are thus non-pathognomonic and demand careful evaluation of differential diagnoses. This review article elucidates the pathogenesis, clinical aspects and radiological image features of the most common alcohol-related CNS diseases and their differential diagnoses.

  10. Combined bilateral idiopathic necrosis of the humerus and femur heads: Bone scan, X-ray, CT, and MRI findings. Kombinierte beidseitige idiopathische Nekrose der Humerus- und Femurkoepfe: Skelettszintigraphie, Roentgen-, CT- und MRT-Befunde

    Energy Technology Data Exchange (ETDEWEB)

    Piepenburg, R.; Hahn, K. (Mainz Univ. (Germany). Klinik fuer Nuklearmedizin); Doll, G. (Mainz Univ. (Germany). Klinik fuer Roentgendiagnostik); Grimm, J. (Mainz Univ. (Germany). Orthopaedische Klinik)

    1992-12-01

    Untreated aseptic bone necroses close to a joint commonly leads to severe secondary arthrosis and destruction of the joint within a short time. Therefore, only a diagnosis in an early stage of the disease offers the chance of a successful joint- preserving therapy. In cases of clinically suspected aseptic bone necrosis but still negative or doubtful X-ray findings, bone scans or MRI are reliable methods of verifying the diagnosis. (orig./MG).

  11. Vaikų galvos smegenų navikų MRT tyrimo diagnostinės vertės nustatytamas prognozuojant histologinį naviko tipą

    OpenAIRE

    Montvila, Antanas

    2016-01-01

    Objective. To determine the diagnostic value of magnetic resonance imaging examination in predicting children's brain tumor histological type on patients who underwent treatment in the Lithuanian University of Health Sciences hospital Kaunas clinics (LSMUL KK) in the last five years (2011-2016) and evaluate tumor-specific radiological features. Research tasks. 1) To compare the results of MRI with histological pediatric brain tumors examination results. 2) To evaluate the diagnosti...

  12. MRI-based flow measurements in the main pulmonary artery to detect pulmonary arterial hypertension in patients with cystic fibrosis; MRT-basierte Flussmessungen im Truncus pulmonalis zur Detektion einer pulmonal-arteriellen Hypertonie in Patienten mit zystischer Fibrose

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    Wolf, T.; Anjorin, A.; Abolmaali, N. [TU Dresden (Germany). OncoRay, Biologisches und Molekulares Imaging; Posselt, H. [Frankfurt Univ. (Germany). Klinik fuer Paediatrie I, Muskoviszidoseambulanz; Smaczny, C. [Frankfurt Univ. (Germany). Medizinische Klinik I, Pneumologie und Allergologie; Vogl, T.J. [Frankfurt Univ. (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie

    2009-02-15

    Development of pulmonary arterial hypertension (PH) is a common problem in the course of patients suffering from cystic fibrosis (CF). This study was performed to evaluate MRI based flow measurements (MR{sub venc}; Velocity ENCoding) to detect signs of an evolving PH in patients suffering from CF. 48 patients (median age: 16 years, range: 10 - 40 years, 25 female) suffering from CF of different severity (mean FEV1: 74 % {+-} 23, mean Shwachman-score: 63 {+-} 10) were examined using MRI based flow measurements of the main pulmonary artery (MPA). Phase-contrast flash sequences (TR: 9.6 ms, TE: 2.5 ms, bandwidth: 1395 Hertz/Pixel) were utilized. Results were compared to an age- and sex-matched group of 48 healthy subjects. Analyzed flow data where: heart frequency (HF), cardiac output (HZV), acceleration time (AT), proportional acceleration time related to heart rate (ATr), mean systolic blood velocity (MFG), peak velocity (Peak), maximum flow (Fluss{sub max}), mean flow (Fluss{sub mitt}) and distensibility (Dist). The comparison of means revealed significant differences only for MFG, Fluss{sub max} and Dist, but overlap was marked. However, using a scatter-plot of AT versus MFG, it was possible to identify five CF-patients demonstrating definite signs of PH: AT = 81 ms {+-} 14, MFG = 46 {+-} 11 cm/s, Dist = 41 % {+-} 7. These CF-patients where the most severely affected in the investigated group, two of them were listed for complete heart and lung transplantation. The comparison of this subgroup and the remaining CF-patients revealed a highly significant difference for the AT (p = 0.000001) without overlap. Screening of CF-patients for the development of PH using MR{sub venc} of the MPA is not possible. In later stages of disease, the quantification of AT, MFG and Dist in the MPA may be useful for the detection, follow-up and control of therapy of PH. MR{sub venc} of the MPA completes the MRI-based follow-up of lung parenchyma damage in patients suffering from CF. (orig.)

  13. 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.)

  14. Cerebral and meningeal manifestations of AIDS: Sensitivity of CT and T sub 2 -weighted MR (129 patients). Zerebrale und meningeale Manifestation des AIDS: Sensitivitaet von CT und T sub 2 -gewichteter MRT (129 Patienten)

    Energy Technology Data Exchange (ETDEWEB)

    Henkes, H.; Schoerner, W.; Jochens, R.; Lang, P.; Felix, R. (Klinikum Rudolf Virchow, Berlin (Germany, F.R.). Radiologische Klinik mit Poliklinik); Ruf, B. (Klinikum Rudolf Virchow, Berlin (Germany, F.R.). 2. Medizinische Klinik); Heise, W. (Auguste Viktoria Krankenhaus, Berlin (Germany, F.R.). 2. Medizinische Klinik); Trautmann, M. (Klinikum Rudolf Virchow, Berlin (Germany, F.R.). Abt. fuer Innere Medizin mit Schwerpunkt Infektionskrankheiten)

    1990-09-01

    We studied 129 AIDS patients with suspected or proved intracranial manifestations of the disease. The purpose of this study was to compare the diagnostic sensitivity of unenhanced and contrast enhanced CT and unenhanced T{sub 2}-weighted MR. Thus, in 20% of our patients MR but not CT was diagnostic. In another 20% MR provided additional diagnostic information. In conclusion, MR is recommended as the imaging modality of choice in AIDS patients with non-conclusive cranial CT. (orig./GDG).

  15. Mystery of alar ligament rupture: Value of MRI in whiplash injuries - biomechanical, anatomical and clinical studies; Mysterium Ligamentum alare Ruptur: Stellenwert der MRT-Diagnostik des Schleudertraumas - biomechanische, anatomische und klinische Studien

    Energy Technology Data Exchange (ETDEWEB)

    Bitterling, H.; Brueckmann, H. [Abt. fuer Neuroradiologie, Klinikum der LMU, Muenchen (Germany); Staebler, A. [Radiologische Praxis, Radiologie in Muenchen, Harlaching (Germany)

    2007-11-15

    Purpose: Whiplash injury of the cervical spine is a frequent issue in medical expertise and causes enormous consequential costs for motor insurance companies. Some authors accuse posttraumatic changes of alar ligaments to be causative for consequential disturbances. Materials and methods: Review of recent studies on biomechanics, anatomical and clinical MR imaging. Results: Biomechanical experiments can not induce according injuries of alar ligaments. Although MRI provides excellent visualization of alar ligaments, the range of normal variants is high. (orig.)

  16. 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.; Chukhraev, N.V.; Shimkov, G.E.; Bitson, A.V.

    1999-01-01

    EHF-therapy method is a principally new method of treatment which is based on the peculiarities in perception by human organism the magnetic radiation of millimeter energy range. Practical use of this method has shown its high therapeutic efficiency at influencing on acupuncture points. This monography is completely devoted to description of EHF-therapy effects on acupuncture points with account of the Chinese reflexotherapy. Apparats of 'MIT' and 'Eleknronika-EHF' series do not provoke any damages in biological structures and refer to the safe class. The proposed scientific and practical materials on the use of physical factors in clinical and health resort practice are edited in addition to the previous monograph under the same title. These materials are of use for physicians of different specializations and listeners of medical advanced courses

  17. MRT measurements of diastolic relaxation of the hypertrophied left ventricle using a single-slice multi-phase technique. MR-tomographische Messungen der diastolischen Relaxation hypertrophierter linker Ventrikel mit Single-slice-multi-phase-Technik

    Energy Technology Data Exchange (ETDEWEB)

    Pitton, M.B. (Klinik und Poliklinik fuer Radiologie, Mainz Univ. (Germany)); Just, M. (Klinik und Poliklinik fuer Radiologie, Mainz Univ. (Germany)); Himmelsbach, F. (1. Medizinische Klinik und Poliklinik, Mainz Univ. (Germany)); Thelen, M. (Klinik und Poliklinik fuer Radiologie, Mainz Univ. (Germany))

    1993-11-01

    In order to assess diastolic ventricular function in hypertensive patients, a single-slice multiphase sequence was used in order to measure contraction and early diastolic relaxation. There was no difference in the contraction velocity between hyperintensives and normals (Vsys.n.r.=56.1[+-]13.8% LVEDV/s vs. 51.7[+-]8.6% LVEDV/s, stat.n.sign.). Early disatolic relaxation velocity in hyperintensives was reduced as compared with the control group (Vdiast.l.n.r.=37.9[+-]13.1% LVEDV/s vs. 47.1[+-]9.6% LVEDV/s, p<0.05). There was no linear relation between abnormal relaxation and the extent of myocardial hypertrophy. Hyperintensives with myocardial hypertrophy frequently had reduced early distolic relaxation velocity. Regression analysis for estimating left ventricular volumes derived from single-slice measurements were confirmed by additional multislice measurements. The calculated LVED correlated at r=0.956 with multi-slice measurements and tended to show lower values (LVEDV n.r.=104.6[+-]30.8 ml vs. LVEDV=102.1[+-]28.8 ml, r=0.956, p<0.05). The LVESV was overestimated by the multi-slice technique, the calculated regression volume averaged 23% lower, realistic values (LVESV n.r.=28.5[+-]15.3 ml vs. LVESV=37.1[+-]15.6 ml, r=0.887, p<0.001). (orig.)

  18. MRI with fat suppression improves visualization of arterial wall hematoma in spontaneous dissection of the internal carotid artery; MRT mit Fettsuppression zur Darstellung des Wandhaematoms bei spontaner Dissektion der A. carotis interna

    Energy Technology Data Exchange (ETDEWEB)

    Fiebach, J.; Knauth, M.; Jansen, O. [Heidelberg Univ. (Germany). Abt. fuer Neuroradiologie; Brandt, T. [Heidelberg Univ. (Germany). Abt. fuer Neurologie

    1999-10-01

    Purpose: Comparison of different MR-examination techniques for the diagnosis of acute spontaneous internal carotid artery dissection. Patients and methods: 13 patients (age range 23-59 years) with symptomatic spontaneous dissection of the internal carotid artery were examined. The MRI protocol contained a transverse spin echo sequence, a time-of-flight MR-angiography and a coronal fat suppressed T{sub 1}-weighted sequence. The earliest examination was performed three days after symptom onset. Follow-up extended up to 30 months. We compared the three different sequences to find out the one that demonstrated the hematoma best. Results: MR-angiography shows a narrowing of the vessel diameter in early examinations. During the subacute stage methemoglobin can obscure this finding. From the third day on fat suppressed T{sub 1}-weighted images showed a hyperintense hematoma that strongly contrasted to the surrounding fatty tissue. Fat suppressed images showed a hyperintense hematoma up to 10 months after symptom onset while MRA and spin echo sequences did not. Conclusions: Fat suppressed T{sub 1}-weighted images are superior in showing vessel wall hematoma and should thus be used in the standard MR-protocol for spontaneous internal carotid artery dissection. (orig.) [German] Zielsetzung: Untersuchung zur Wertigkeit einer fettsupprimierten T{sub 1}-gewichteten Sequenz in der MR-Diagnostik bei spontanen Dissektionen der extrakraniellen Arteria carotis interna. Material und Methoden: 13 Patienten im Alter von 23-59 Jahren mit symptomatischer spontaner Karotisdissektion wurden mit transversalen T{sub 2}-gewichteten SE-Sequenzen, MR-Angiographie (TOF) und koronaren fettsupprimierenden T{sub 1}-gewichteten Sequenzen untersucht. Die frueheste MR-Untersuchung fand 3 Tage nach Symptombeginn, die letzte Verlaufsuntersuchung nach 30 Monaten statt. Bestimmt wurde, welche der drei Sequenzen das Wandhaematom bei Dissektion am deutlichsten erfasst. Ergebnisse: In der Fruehphase der Dissektion zeigt die MR-Angiographie eine Einengung des Gefaesslumens durch das Wandhaematom, das im weiteren Verlauf wegen der Entwicklung von Methaemoglobin die Stenose verdecken kann. Mit fettsupprimierten T{sub 1}-gewichteten Sequenzen konnte ab dem dritten Tag ein deutlich hyperintenses Wandhaematom mit hohem Kontrast zum signalunterdrueckten perivaskulaeren Fettgewebe nachgewiesen werden. Im Vergleich zu MRA und SE-Sequenzen war mit der fettsupprimierten T{sub 1}-gewichteten Sequenz das Haematom bis zu 10 Monaten nach Erkrankungsbeginn nachweisbar. Schlussfolgerung: Mit koronaren fettsupprimierten T{sub 1}-Sequenzen koennen Gefaesswandhaematome der extrakraniellen Arteria carotis interna besser dargestellt werden. Diese Untersuchungstechnik sollte daher bei der Frage nach Karotisdissektion in das MR-Protokoll aufgenommen werden. (orig.)

  19. White paper. Interventional MRI. Current status and potential for development considering economic perspectives. Pt. 1. General application; White Paper. Interventionelle MRT. Status Quo und Entwicklungspotenzial unter oekonomischen Perspektiven. T. 1. Generelle Anwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Barkhausen, Joerg [Univ. Hospital Schleswig Holstein, Luebeck (Germany). Dept. of Radiology and Nuclear Medicine; Kahn, Thomas [Clinic and Policlinic for Diagnostic and Interventional Radiology, Leipzig (Germany); Krombach, Gabriele A. [Univ. Hospital Giessen (Germany). Dept. of Radiology; Kuhl, Christiane K. [Univ. Hospital RWTH Aachen (Germany). Dept. of Diagnostic and Interventional Radiology; Lotz, Joachim [Univ. Goettingen (Germany). Inst. for Diagnostic and Interventional Radiology; Maintz, David [Univ. Hospital Cologne (Germany). Dept. of Radiology; Ricke, Jens [Univ. Hospital Magdeburg (Germany). Dept. of Radiology and Nuclear Medicine; Schoenberg, Stefan O. [Heidelberg Univ. - Univ. Medical Center Mannheim (Germany). Inst. of Clinical Radiology and Nuclear Medicine; Vogl, Thomas J. [Univ. Hospital Frankfurt (Germany). Dept. of Diagnostic and Interventional Radiology; Wacker, Frank K. [Hannover Medical School (Germany). Dept. for Diagnostic and Interventional Radiology

    2017-07-15

    MRI is attractive for the guiding and monitoring of interventional procedures due to its high intrinsic soft tissue contrast and the possibility to measure physiologic parameters like flow and cardiac function. The current status of interventional MRI for the clinical routine was analyzed. The effort needed for the development of MR-safe monitoring systems and instruments initially resulted in the application of interventional MRI only for procedures that could not be performed by other means. Accordingly, biopsy of lesions in the breast, which are not detectable by other modalities, has been performed under MRI guidance for decades. Currently, biopsies of the prostate under MRI guidance are established in a similar fashion. At many sites blind biopsy has already been replaced by MR-guided biopsy or at least by the fusion of MR images with ultrasound. Cardiovascular interventions are performed at several centers for ablation as a treatment for atrial fibrillation. Interventional MRI has been established in the clinical routine for a variety of indications. Broader application can be expected in the clinical routine in the future owing to the multiple advantages compared to other techniques.

  20. Whole-body MR imaging in children with suspected osteonecrosis after intensive chemotherapy: preliminary results; Ganzkoerper-MRT bei Kindern mit Verdacht auf Osteonekrose nach intensiver Chemotherapie: Erste Ergebnisse

    Energy Technology Data Exchange (ETDEWEB)

    Beer, M.; Stenzel, M.; Darge, K. [Universitaetsklinikum Wuerzburg (Germany). Inst. fuer Roentgendiagnostik; Girschick, H.; Schlegel, P.G. [Universitaetsklinikum Wuerzburg (Germany). Kinderklinik

    2008-03-15

    Purpose: use of multidrug chemotherapy poses the risk of avascular osseous necroses in children. Depiction of the whole body, including clinically non-apparent sites is mandatory for starting early and proper treatment, including surgical approaches in lesions near the joints. We analyzed the value of whole-body MRI in the detection of osteonecrosis, (1) in relation to conventional X-ray imaging and clinical symptoms, (2) using different MRI sequences, (3) with follow-up examinations. Materials and methods: 5 patients suffering from an oncological disease, 13 to 16 years old (3 x ALL, 1 x medulloblastoma, 1 x CML), and recently developing bone pain were examined with X-ray imaging of the particular region and a whole-body MRI (T2w TIRM, T1w TSE sequences, pre- and post-contrast GD-DTPA, including fat suppression techniques). Neck/thorax/abdomen/pelvis, and upper and lower extremities were acquired in the coronal plane, and the feet in sagittal orientation. 4 of 5 patients had at least one follow-up examination (in the mean after 10 {+-} 4 months). Results: none of the initial X-ray images revealed an abnormal finding. The whole-body MRI showed in 4 of 5 children bone marrow lesions compatible with osteonecrosis. The locations were around the knee joints (n = 3) and the tibiae/ankle joints (n = 4). In addition to the symptomatic sites, MRI revealed additional lesions at the following sites: humerus (n = 5), hip joints (n = 4), knee joints (n = 6), ankle joints (n = 4). The size varied from small focal lesions to lesions measuring 90% of the whole transverse diameter of the bone. The lesions were able to be detected most easily with heavily T2-weighted (TIRM) sequences, and the diagnosis was most easily established using the non-enhanced TSE T1-weighted sequences. As a consequence of the results of the whole-body MRI, all patients with lesions compatible with osteonecrosis received symptomatic (n = 2) or specific (n = 2) therapy. In the follow-up examinations, a higher number of patients showed no changes in the lesions as to size and distribution. 2 patients showed partial resolution of the osteonecroses. (orig.)

  1. Differential diagnosis of intraconal orbital masses using high-resolution MRI with surface coils in 78 patients; Differenzialdiagnostik intrakonaler orbitaler Raumforderungen unter Verwendung der hochaufloesenden MRT mit Oberflaechenspulen anhand von 78 Patienten

    Energy Technology Data Exchange (ETDEWEB)

    Lemke, A.-J.; Kazi, I.; Felix, R. [Universitaetsklinikum Charite, Berlin (Germany). Klinik fuer Strahlenheilkunde; Landeck, L.M. [Universitaetsklinikum Charite, Berlin (Germany). Venerologie und Allergologie; Zaspel, U. [Universitaetsklinikum Charite, Berlin (Germany). Institut fuer Radiologie; Hosten, N. [Universitaet Greifswald (Germany). Institut fuer Diagnostische Radiologie

    2004-10-01

    Purpose: Over the last decade, MRI has become the standard procedure for the diagnosis of orbital masses. Purpose of the study was to evaluate criteria for differential diagnosis for intraconal masses on MRI in a large patient group. Material and Methods: In a retrospective study, MR examinations of 78 patients with intraconal masses were evaluated. All examinations were performed using surface coils for high spatial resolution. Signal behavior on T2-WI and T1-WI before and after contrast application as well as further tumor characteristics (i.e., shape, size, position, delineation and infiltration) were evaluated. Every diagnosis was proven by histopathological results from extirpation (n=18) or biopsy (n=22), or confirmed by other imaging modalities (n=13) or clinical course (n=25). Results: Different tumor characteristics are helpful in the differentiation between cavernous hemangioma, lymphangioma, varices, AV malformations and solid tumors. Due to overlapping in the imaging appearance, the differentiation between inflammatory pseudotumor, lymphoma and orbital metastasis was more difficult. (orig.)

  2. Cerebral lesions in acute arterial hypertension: the characteristic MRI in hypertensive encephalopathy; Zerebrale Veraenderungen bei krisenhafter arterieller Hypertonie: MRT-Befunde der hypertensiven Enzephalopathie sind wegweisend fuer Diagnose und Therapie

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, J.P.; Krohmer, S. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Abt. Neuroradiologie, Universitaetsklinikum Leipzig AoeR (Germany); Guenther, A. [Klinik und Poliklinik fuer Neurologie, Universitaetsklinikum Leipzig AoeR (Germany); Zimmer, C. [Abt. fuer Neuroradiologie, Klinikum rechts der Isar der TU Muenchen (Germany)

    2006-06-15

    Purpose: in the nine years since the posterior reversible (leuc) encephalopathy syndrome (PRES) was first described, a number of causes have been under discussion. These not only include arterial hypertension, i. e. hypertensive crises, but also various toxic substances, i. e. immunosuppressive or chemotherapeutic agents, that are responsible for the formation of the symptoms and characteristic MR tomographic brain findings. Materials and methods: initial and follow-up MRI examinations of 8 patients were analyzed. All patients had acute neurological symptoms (headaches, seizures, visual disorders and vigilance disturbances) together with a detectable hypertensive crisis. Results: MRI disclosed increased signal intensity in subcortical and some cortical lesions in all patient FLAIR sequences. These changes were particularly extensive in the posterior circulation (occipital, cerebellum and brain stem) although they were also detected in brain areas supplied by the carotid artery. However, a cytotoxic genesis of the changes was ruled out in each patient by means of a normal DWI. Furthermore, when the blood pressure was normalized, reversibility of the lesions as proof of the diagnosis was detectable. (orig.)

  3. Interventional MRI. Current status and potential for development considering economic perspectives. Pt. 2. Liver and other applications in oncology; Interventionelle MRT. Status Quo und Entwicklungspotenzial unter oekonomischen Perspektiven. T. 2. Therapeutische und onkologische Anwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Barkhausen, Joerg [Univ. Hospital Schleswig Holstein, Luebeck (Germany). Dept. of Radiology and Nuclear Medicine; Kahn, Thomas [Clinic and Policlinic for Diagnostic and Interventional Radiology, Leipzig (Germany); Krombach, Gabriele A. [Univ. Hospital Giessen (Germany). Dept. of Radiology; Kuhl, Christiane K. [Univ. Hospital RWTH Aachen (Germany). Dept. of Diagnostic and Interventional Radiology; Lotz, Joachim [Goettingen Univ. (Germany). Inst. for Diagnostic and Interventional Radiology; Maintz, David [Univ. Hospital Cologne (Germany). Dept. of Radiology; Ricke, Jens [Univ. Hospital Magdeburg (Germany). Dept. of Radiology and Nuclear Medicine; Schoenberg, Stefan O. [Univ. Medical Center Mannheim, Heidelberg Univ., Mannheim (Germany). Inst. of Clinical Radiology and Nuclear Medicine; Vogl, Thomas J. [Frankfurt Univ. Hospital (Germany). Dept. of Diagnostic and Interventional Radiology; Wacker, Frank K. [Hannover Medical School (Germany). Dept. for Diagnostic and Interventional Radiology

    2017-11-15

    MRI is attractive for guiding and monitoring interventional procedures due to its high intrinsic soft tissue contrast and the possibility to measure flow and cardiac function. Technical solutions have been developed for all procedural steps including imaging guidance, MR-safe catheters and instruments and patient monitoring. This has led to widening of the clinical applications. Interventional MRI is becoming increasingly important for the treatment of patients suffering from malignant diseases. The detectability of masses and consequently their accessibility for biopsy is higher, compared to other modalities, due to the high intrinsic soft tissue contrast of MRI. Temperature-dependent sequences allow for minimally invasive and tissue-sparing ablation (A-0 ablation). Interventional MRI has become established in the clinical routine for a variety of indications, including biopsies and tumor ablation. Since the economic requirement of covering costs by reimbursement is met and interventional MRI decreases the mortality and morbidity of interventional procedures, broader application of interventional MRI can be expected in the clinical routine in the future.

  4. Effects of MRI-assayed microvascular permeability on the accumulation of vinorelbine in xenograft tumors; Einfluss der mittels MRT bestimmten mikrovaskulaeren Permeabilitaet auf die Akkumulation von Vinorelbine in experimentellen Xenograft-Tumoren

    Energy Technology Data Exchange (ETDEWEB)

    Raatschen, H.J. [Klinik und Hochschulambulanz fuer Radiologie, Charite Universitaetsmedizin Berlin (Germany); Center for Pharmaceutical and Molecular Imaging, Dept. of Radiology, Univ. of California, San Francisco, CA (United States); Fu, Y.; Rogut, V.; Brasch, R.C. [Center for Pharmaceutical and Molecular Imaging, Dept. of Radiology, Univ. of California, San Francisco, CA (United States); Simon, G.H. [Center for Pharmaceutical and Molecular Imaging, Dept. of Radiology, Univ. of California, San Francisco, CA (United States); Abt. fuer Diagnostische und Interventionelle Radiologie, Nuklearmedizin, Klinikum Garmisch-Partenkirchen (Germany); Sennino, B. [Cardiovascular Research Inst., Comprehensive Cancer Center, Univ. of California, San Francisco, CA (United States); Wolf, K.J. [Klinik und Hochschulambulanz fuer Radiologie, Charite Universitaetsmedizin Berlin (Germany)

    2010-02-15

    Purpose: To determine the effects of MRI-assayed vascular leakiness on the delivery of macro-molecular therapeutics to tumors. Materials and Methods: MDA-MB 435 tumors, subcutaneously implanted into nude rats were treated with a single dose of bevacizumab at levels of 0.1 mg (n = 5) or 1.0 mg (n = 10) or received saline (control animals, n = 8). After 24 hours, albumin-(Gd-DTPA){sub 30}-enhanced MRI was performed. Just prior to MRI, the cytotoxic drug vinorelbine was administered intravenously. Upon completion of the MR experiment, tumor vinorelbine concentrations were quantified by high performance liquid chromatography (HPLC). Vascular leakiness (K{sup PS}) was calculated based on the MRI data using a pharmacokinetic model. Results: K{sup PS} was calculated as 3.70 {+-} 1.12 (control tumors), 1.95 {+-} 0.70 (0.1 mg group) and 0.75 {+-} 0.46 {mu}l min{sup -1}cm{sup -3} (1.0 mg group). K{sup PS} was significantly higher in the control group compared to the 1.0 mg bevacizumab group. Vinorelbine concentrations were measured as 409.4 {+-} 109.7 (control tumors), 387.5 {+-} 47.5 (0.1 mg group) and 250.7 {+-} 71.9 (1.0 mg group). These differences were not significant. A moderate and significant correlation was found between K{sup PS} and Vinorelbine concentrations in tumors (r = 0.49, p < 0.05). Conclusion: MRI-assayed K{sup PS} based on dynamic MRI enhanced by albumin-(Gd-DTPA){sub 30} correlated significantly with vinorelbine accumulation in experimental xenograft tumors under angiogenesis inhibition. Thus, the MRI technique applied in our study could potentially help to predict accumulation of macromolecular cytotoxic drugs and to optimize individual therapeutic regimes in tumors. (orig.)

  5. Coronary artery anomalies. Diagnosis and classification based on cardiac CT and MRI (CMR) - from ALCAPA to anomalies of termination; Koronararterienanomalien. Diagnostik und Klassifikation auf Basis der CT und MRT des Herzens - von ALCAPA bis Terminationsanomalie

    Energy Technology Data Exchange (ETDEWEB)

    Heermann, Philipp; Heindel, Walter; Schuelke, Christoph [University Hospital Muenster (UKM) (Germany). Dept. of Clinical Radiology

    2017-01-15

    Coronary artery anomalies encompass a clinically and anatomically variable spectrum including physiological variants and pathophysiologically relevant anomalies. The majority of the variants has no hemodynamic relevance and is often detected accidentally. The recognition of the rare and relevant anomalies that cause either relevant shunt volumes leading to myocardial ischemia or ventricular tachyarrhythmias with the risk of sudden cardiac death is of major importance. This review is based on a literature search in PubMed conducted using the key words ''coronary artery'' and/or ''anomaly'' and/or ''anomalous origin'' and/or ''myocardial bridging'' and/or ''coronary artery fistula'' and/or ''Bland-White-Garland'' and/or ''ALCAPA''. Coronary artery anomalies can be anatomically subdivided into anomalies of origin, course and termination. The method of choice for anatomical imaging is ECG-triggered or gated multislice CT (MSCT) that provides high spatial resolution and the capability of multiplanar reconstructions. It facilitates the delineation of the precise course of all three coronary arteries and thus allows for correct classification in the anatomical classification system of coronary artery anomalies. The strengths of cardiac magnetic resonance imaging (CMR) are the evaluation of cardiac morphology, myocardial tissue properties and myocardial function. Basic methods are the analysis of myocardial contraction and perfusion with and without pharmacologic stress. Furthermore, potential shunt volumes could be quantified by phase contrast imaging or volumetry.

  6. Multiple cerebral cavernous malformations: typical pattern on MR imaging and appearance of a new lesion in the follow-up MRI; Multiple zerebrale kavernoese Angiome - Klassischer MRT-Befund mit Nachweis einer de-novo Gefaessmalformation im Verlauf

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, J.; Bewermeyer, H. [Neurologische Klinik, Kliniken der Stadt Koeln, Krankenhaus Merheim (Germany); Knitelius, H.O. [Radiologische Klinik, Kliniken der Stadt Koeln, Krankenhaus Merheim (Germany)

    2004-07-01

    Cerebral cavernous malformations (CCM) are common, mostly benign vascular anomalies of the CNS. Clinical features are seizures, headache and focal neurological signs. Often they are asymptomatic. Apart from sporadically cases CCM occur as an autosomal dominant condition. Familial cases are associated with a high frequency of multiple lesions. MRI is most sensitive in the detection of cavernous malformations. The MRI findings of CCM are variable, depending on hemorrhage and calcifications. The typical appearance of CCM are heterogenous ''popcorn-like'' lesions of different size with a mixed signal core and a hypointense hemosiderin rim. Our report concerns a 22 year old man with multiple cerebral cavernous malformations whose follow-up MRI of brain showed the appearance of a new lesion. (orig.)

  7. Retrospective 5-year analysis of MR-guided biopsies in a low-field MR system; Retrospektive Analyse der 5-jahres-Ergebnisse von MRT-gesteuerten Biopsien im Niederfeldsystem

    Energy Technology Data Exchange (ETDEWEB)

    Zangos, Stephan; Mueller, C.; Mayer, F.; Naguib, N.N.; Nour-Eldin, N.E.A.; Herzog, C.; Hammerstingl, R.M.; Thalhammer, A.; Mack, M.G.; Vogl, T.J.; Eichler, K. [Inst. fuer Diagnostische und Interventionelle Radiologie, J.-W.-Goethe-Univ. Frankfurt (Germany); Hansmann, M.L. [Senckenbergisches Inst. fuer Pathologie, J.-W.-Goethe-Univ. Frankfurt (Germany)

    2009-07-15

    Purpose: The purpose of this study was to evaluate the safety and clinical value of MR-guided biopsies in an open 0.2 T low-field system. Materials and methods: A total of 322 patients with suspicious lesions of different body regions were biopsied in a low-field MRI system (0.2 T, Concerto, Siemens). The procedures were guided using T1-weighted Flash sequences (TR/TE = 100/9; 70 ). The lesions were repeatedly biopsied using the coaxial technique with a 15-gauge (diameter 2 mm) puncture needle. Complications and biopsy findings were analyzed retrospectively. Results: In all cases the biopsy procedures were successfully performed with MR guidance. In 298 patients diagnosis was able to be confirmed on the basis of the probes. The clinical follow-up showed that in 24 patients the lesions were missed by MR-guided biopsy. From this a sensitivity of 86%, a specificity of 87% and an accuracy of 93% were calculated. In two patients major complications were observed (morbidity rate 0.6%). Conclusion: MR-guided biopsy can be performed safely and precisely in a low-field MR system and are a supplement to US or CT-guided biopsies. (orig.)

  8. MRI in the early stage of spinal cord injury: does it have clinical relevance? An experimental study; Hat die MRT in der Fruehphase des spinalen Traumas klinische Relevanz? Eine experimentelle Studie

    Energy Technology Data Exchange (ETDEWEB)

    Hannmann, T.T. [Universitaetsklinikum Heidelberg (Germany). Abt. fuer Neuroradiologie; Freund, M. [Klinikum Aschaffenburg (Germany). Inst. fuer Radiologie und Neuroradiologie

    2007-05-15

    Purpose: An experimental technique for producing a ventral spinal trauma which imitates a slipped intervertebral disc or a fractured vertebra was evaluated using magnetic resonance imaging and histology. The results were evaluated with respect to their clinical importance. Materials and Methods: A total of 69 Wistar rats were used for this study. An inflatable angioplasty balloon device was placed dorsally or ventrally to the spinal cord in order to produce a spinal trauma. 30 rats were used to compare neurological pathologies between ventral and dorsal trauma. 30 animals underwent graded ventral spinal cord compression. Magnetic resonance imaging was performed and the results were compared to histology. Results: Using this technique, the balloon device can be placed ventrally to the spinal cord. The compression time had a direct effect on changes on magnetic resonance images and edema in histology, but a longer compression time did not produce increased bleeding. The T2-weighted MRI scans showed hyperintense changes immediately after spinal compression. Therefore, they are the appropriate way for diagnosing acute spinal injuries. Although the T1-weighted MRI scans did not change after spinal compression, they are important for diagnosing epidural hematomas. (orig.)

  9. Noninvasive MRI-based liver iron quantification. Methodic approaches, practical applicability and significance; Nicht invasive MRT-basierte Bestimmung des Leber-Eisen-Gehalts. Methodische Ansaetze, Anwendbarkeit in der Praxis und Aussagekraft

    Energy Technology Data Exchange (ETDEWEB)

    Wunderlich, A.P. [Universitaetsklinikum Ulm (Germany). Section for Experimental Radiology; Universitaetsklinikum Ulm (Germany). Clinic for Diagnostic and Interventional Radiology; Cario, H. [Universitaetsklinikum Ulm (Germany). Dept. of Pediatrics and Adolescent Medicine; Juchems, M.S. [Konstanz Hospital (Germany). Diagnostic and Interventional Radiology; Beer, M.; Schmidt, S.A. [Universitaetsklinikum Ulm (Germany). Clinic for Diagnostic and Interventional Radiology

    2016-11-15

    Due to the dependence of transverse relaxation times T{sub 2} and T{sub 2}* on tissue iron content, MRI offers different options for the determination of iron concentration. These are the time-consuming spin-echo sequence as well as the gradient-echo sequence. For the latter, several data analysis approaches have been proposed, with different requirements for acquisition and post-processing: the mathematically challenging R{sub 2}* analysis and the signal-intensity ratio method with its high demand on the signal homogeneity of MR images. Furthermore, special procedures currently under evaluation are presented as future prospects: quantitative susceptibility imaging, as a third approach for analyzing gradient echo data, and multi-contrast spin-echo using repeated refocusing pulses. MR theory, as far as needed for understanding the methods, is briefly depicted.

  10. Pituitary gland tumors; Hypophysentumoren

    Energy Technology Data Exchange (ETDEWEB)

    Jesser, J.; Schlamp, K.; Bendszus, M. [Radiologische Klinik, Universitaetsklinikum Heidelberg, Abteilung fuer Neuroradiologie, Heidelberg (Germany)

    2014-10-15

    This article gives an overview of the most common tumors of the pituitary gland and the differential diagnostics with special emphasis on radiological diagnostic criteria. A selective search of the literature in PubMed was carried out. Pituitary adenomas constitute 10-15 % of all intracranial tumors and are the most common tumors of the sellar region. Tumors smaller than 1 cm in diameter are called microadenomas while those larger than 1 cm in diameter are called macroadenomas. Approximately 65 % of pituitary gland adenomas secrete hormones whereby approximately 50 % secrete prolactin, 10 % secrete growth hormone (somatotropin) and 6 % secrete corticotropin. Other tumors located in the sella turcica can also cause endocrinological symptoms, such as an oversecretion of pituitary hormone or pituitary insufficiency by impinging on the pituitary gland or its stalk. When tumors spread into the space cranial to the sella turcica, they can impinge on the optic chiasm and cause visual disorders. A common differential diagnosis of a sellar tumor is a craniopharyngeoma. In children up to 10 % of all intracranial tumors are craniopharyngeomas. Other differential diagnoses for sellar tumors are metastases, meningiomas, epidermoids and in rare cases astrocytomas, germinomas or Rathke cleft cysts As these tumors are located in an anatomically complex region of the skull base and are often very small, a highly focused imaging protocol is required. The currently favored modality is magnetic resonance imaging (MRI) with the administration of a contrast agent. The sellar region should be mapped in thin slices. In cases of suspected microadenoma the imaging protocol should also contain a sequence with dynamic contrast administration in order to assess the specific enhancement characteristics of the tumor and the pituitary gland. (orig.) [German] Diese Arbeit ist eine Uebersicht ueber die haeufigsten Hypophysentumoren und deren Differenzialdiagnosen mit Augenmerk auf die

  11. Two Readiness Measures As Predictors Of First- And Third-Grade Reading Achievement

    Science.gov (United States)

    Randel, Mildred A.; And Others

    1977-01-01

    Multiple-regression procedures were used to assess effectiveness of the ABC Inventory and the Metropolitan Readiness Test (MRT) in predicting first- and third-grade reading achievement. MRT performance accounted for 11 percent of the variance in first-grade SRA reading scores. In predicting third-grade reading, the MRT accounted for 26 percent of…

  12. Differential diagnoses of spinal tumors; Differenzialdiagnose spinaler Tumoren

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, U. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany)

    2011-12-15

    A wide variety of degenerative, inflammatory and vascular diseases can resemble the clinical presentation and imaging findings of spinal tumors. This article provides an overview of the most frequent diseases which are important to recognize for diagnostic imaging of the spine. (orig.) [German] Eine Vielzahl degenerativer, entzuendlicher und vaskulaerer Erkrankungen kann das klinische Bild und radiologische Befunde spinaler Tumoren imitieren. Dieser Artikel dient der Uebersicht ueber die haeufigsten dieser Erkrankungen, deren Kenntnis wichtig fuer die spinale Bildgebung ist. (orig.)

  13. Ideas on how to explain differences in radiation sensitivity; Vorstellungen zur Erklaerung der Unterschiede in der individuellen Strahlenempfindlichkeit

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, W.U. [Essen Univ. (Gesamthochschule) (Germany). Inst. fuer Medizinische Strahlenbiologie

    2001-07-01

    At present there is only fragmentary knowledge on the mechanisms underlying individual radiation sensitivity. This paper endeavours to clarify some principles and put forward ideas on this issue. The synopsis it provides deals exclusively with ionising radiation. [German] Die der individuellen Strahlenempfindlichkeit zugrunde liegenden Mechanismen sind derzeit nur bruchstueckhaft bekannt. Deshalb wird versucht, einige Prinzipien deutlich zu machen und Denkanstoesse zu liefern. In der Uebersicht geht es ausschliesslich um die Empfindlichkeit gegenueber ionisierender Strahlung. (orig.)

  14. Estimating the accuracy of muscle response testing: two randomised-order blinded studies.

    Science.gov (United States)

    Jensen, Anne M; Stevens, Richard J; Burls, Amanda J

    2016-11-30

    Manual muscle testing (MMT) is a non-invasive assessment tool used by a variety of health care providers to evaluate neuromusculoskeletal integrity, and muscular strength in particular. In one form of MMT called muscle response testing (MRT), muscles are said to be tested, not to evaluate muscular strength, but neural control. One established, but insufficiently validated, application of MRT is to assess a patient's response to semantic stimuli (e.g. spoken lies) during a therapy session. Our primary aim was to estimate the accuracy of MRT to distinguish false from true spoken statements, in randomised and blinded experiments. A secondary aim was to compare MRT accuracy to the accuracy when practitioners used only their intuition to differentiate false from true spoken statements. Two prospective studies of diagnostic test accuracy using MRT to detect lies are presented. A true positive MRT test was one that resulted in a subjective weakening of the muscle following a lie, and a true negative was one that did not result in a subjective weakening of the muscle following a truth. Experiment 2 replicated Experiment 1 using a simplified methodology. In Experiment 1, 48 practitioners were paired with 48 MRT-naïve test patients, forming unique practitioner-test patient pairs. Practitioners were enrolled with any amount of MRT experience. In Experiment 2, 20 unique pairs were enrolled, with test patients being a mix of MRT-naïve and not-MRT-naïve. The primary index test was MRT. A secondary index test was also enacted in which the practitioners made intuitive guesses ("intuition"), without using MRT. The actual verity of the spoken statement was compared to the outcome of both index tests (MRT and Intuition) and their mean overall fractions correct were calculated and reported as mean accuracies. In Experiment 1, MRT accuracy, 0.659 (95% CI 0.623 - 0.695), was found to be significantly different (p Experiment 2 replicated the findings of Experiment 1. Testing for

  15. 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...

  16. High resolution 3D dosimetry for microbeam radiation therapy using optical CT

    OpenAIRE

    McErlean, C.; Braeuer-Krisch, E.; Adamovics, J.; Leach, M. O.; Doran, S. J.

    2014-01-01

    International audience; Optical Computed Tomography (CT) is a promising technique for dosimetry of Microbeam Radiation Therapy (MRT), providing high resolution 3D dose maps. Here different MRT irradiation geometries are visualised showing the potential of Optical CT as a tool for future MRT trials. The Peak-to-Valley dose ratio (PVDR) is calculated to be 7 at a depth of 3mm in the radiochromic dosimeter PRESAGE (R). This is significantly lower than predicted values and possible reasons for th...

  17. 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

  18. 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.

  19. 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.

  20. 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.)

  1. Assessment of Valvular Disorders in Survivors of Hodgkin's Lymphoma Treated by Mediastinal Radiotherapy ± Chemotherapy.

    Science.gov (United States)

    Bijl, Jesse M; Roos, Marleen M; van Leeuwen-Segarceanu, Elena M; Vos, Josephine M; Bos, Willem-Jan W; Biesma, Douwe H; Post, Marco C

    2016-02-15

    As the number of Hodgkin's lymphoma (HL) survivors grows, understanding long-term complications becomes more important. Mediastinal radiotherapy (MRT) seems to cause valvular disease, and the prevalence might increase during follow-up. In this cross-sectional study 82 HL survivors participated (52% men, mean age 47.8 years, 50 treated with MRT). Valvular disease was diagnosed by transthoracic echocardiography and compared between HL survivors treated with and without MRT. Univariate and multivariate logistic regression analysis was used to identify predictors for valvular disease. During a median follow-up of 13.4 years (range 2 to 39 years), ≥ mild valvular disease was present in 61.2% of HL survivors with MRT (n = 30), compared with 31.0% of HL survivors without MRT (n = 9; odds ratio [OR] 3.51, 95% CI 1.32 to 9.30, p = 0.01). In multivariate analysis, only current age remained predictive for ≥ mild valvular disease (OR 1.08 per year, 95% CI 1.01 to 1.14, p = 0.023). Aortic regurgitation (AR) was most prevalent and irradiated patients had significantly more ≥ mild AR (38.2% vs 6.8%, p = 0.007). Within the MRT subgroup, time after radiation of >15 years was associated with AR (OR 4.70, 95% CI 1.05 to 21.03, p = 0.043), after adjusting for current age and hypertension. Severe valvular disease was present in 24.5% of HL survivors with MRT compared with 3.4% without MRT (p = 0.016). Valvular surgery was performed in 9 HL survivors (18.0%) with MRT and in none without MRT. In conclusion, the prevalence of valvular disease in HL survivors treated with MRT is high and increases with time after irradiation. Long-time screening for valvular disease by transthoracic echocardiography might be worthwhile. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. 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

  3. Dynamic MR imaging: Follow-up study after femoral head core decompression and rhBMP-2 instillation in patients with avascular necrosis of the femoral head; Dynamische Magnetresonanztomographie (MRT): Verlaufsbeobachtung nach Femurkerndekompression und Auffuellung mit rekombinantem, humanem Bone morphogenetic Protein-2 (rhBMP-2) bei avaskulaerer Femurkopfnekrose

    Energy Technology Data Exchange (ETDEWEB)

    Schedel, H. [Klinik Prof. Schedel, Kellberg (Germany); Schneller, A. [Humboldt-Universitaet, Berlin (Germany). Klinik fuer Allgemein- und Transplantationschirurgie; Vogl, T.; Mueller, H.F.; Maeurer, J.; Felix, R. [Humboldt-Universitaet, Berlin (Germany). Strahlenklinik und Poliklinik; Suedkamp, N. [Humboldt-Universitaet, Berlin (Germany). Unfall- und Wiederherstellungschirurgie; Eisenschenk, A. [Freie Univ. Berlin (Germany). Orthopaedische Klinik und Poliklinik

    2000-07-01

    Material and Methods: Six patients with avascular necrosis of the femoral head ARCO-stage I- or II-lesions were treated surgically by femoral head core decompression. Three of these patients were additionally treated with rhBMP-2-instillation. The progression or regression could be confirmed by T1- and T2-weighted spinecho-sequences (zero, four, ten, sixteen weeks and 24 months follow up). Results: Corresponding ARCO-classification with partly more sensitive measurement of vitality signs in comparison to the optical X-ray classification. The objective, quantitative measurement of signalintensity post contrast medium reduces the influence of experience and level of education. The dynamic sequences results are reproducable. (orig.) [German] Material und Methoden: Sechs Patienten mit avaskulaerer Nekrose des Femurkopfes des Stadiums I oder II nach ARCO wurden einer Femurkerndekompression unterzogen. Drei dieser Patienten erhielten zusaetzlich eine rhBMP-2-Auffuellung. Zum Zeitpunkt null, vier, zehn, sechszehn Wochen und 24 Monaten post OP erfolgte die kernspintomographische Untersuchung mit T1- und T2-gewichteten Sequenzen unter besonderer Beruecksichtigung der dynamischen Untersuchungssequenz nach Gabe von Gd-DTPA (Gadopentetsaeure, Dimegluminsalz; Magnevist {sup trademark}) zur Dokumentation der Signalintensitaetssteigerung pro Zeiteinheit in der Nekroseregion. Ergebnisse: Uebereinstimmende Stadienklassifikation nach ARCO mit zum Teil empfindlicherer Messung von Vitalitaetszeichen im Vergleich zu rein visuellen roentgenologischen Einteilung. Die objektive, quantitative Messung des Signalintensitaetssteigerungsverhaltens nach Kontrastmittelgabe im Bereich der Femurkopfnekrose kann den Einfluss von subjektiven Eigenschaften des Untersuchers (Erfahrung, Ausbildungsstand) reduzieren, wobei die Ergebnisse der Dynamiksequenzen objektiv reproduzierbar sind. (orig.)

  4. Does the individual adaption of standardized speech paradigmas for clinical functional Magnetic Resonance Imaging (fMRI) effect the localization of the language-dominant hemisphere and of Broca's and Wernicke's areas; Beeinflusst die individuelle Anpassung standardisierter Sprachparadigmen fuer die klinische funktionelle Magnetresonanztomographie (fMRT) die Lokalisation der sprachdominanten Hemisphaere, des Broca- und des Wernicke-Sprachzentrums?

    Energy Technology Data Exchange (ETDEWEB)

    Konrad, F.; Nennig, E.; Kress, B.; Sartor, K.; Stippich, C. [Abteilung Neuroradiologie, Neurologische Klinik, Universitaetsklinikum Heidelberg (Germany); Ochmann, H. [Neurochirurgische Klinik, Universitaetsklinikum Heidelberg (Germany)

    2005-03-01

    Purpose: Functional magnetic resonance imaging (fMRI) localizes Broca's area (B) and Wernicke's area (W) and the hemisphere dominant for language. In clinical fMRI, adapting the stimulation paradigms to each patient's individual cognitive capacity is crucial for diagnostic success. To interpret clinical fMRI findings correctly, we studied the effect of varying frequency and number of stimuli on functional localization, determination of language dominance and BOLD signals. Materials and Methods: Ten volunteers (VP) were investigated at 1.5 Tesla during visually triggered sentence generation using a standardized block design. In four different measurements, the stimuli were presented to each VP with frequencies of (1/1)s, (1/2)s,(1/3)s and (1/6)s. Results: The functional localizations and the correlations of the measured BOLD signals to the applied hemodynamic reference function (r) were almost independent from frequency and number of the stimuli in both hemispheres, whereas the relative BOLD signal changes ({delta}S) in B and W increased with the stimulation rate, which also changed the lateralization indices. The strongest BOLD activations were achieved with the highest stimulation rate or with the maximum language production task, respectively. Conclusion: The adaptation of language paradigms necessary in clinical fMRI does not alter the functional localizations but changes the BOLD signals and language lateralization which should not be attributed to the underlying brain pathology. (orig.)

  5. Master Resilience Training in the U.S. Army

    Science.gov (United States)

    Reivich, Karen J.; Seligman, Martin E. P.; McBride, Sharon

    2011-01-01

    The U.S. Army Master Resilience Trainer (MRT) course, which provides face-to-face resilience training, is one of the foundational pillars of the Comprehensive Soldier Fitness program. The 10-day MRT course is the foundation for training resilience skills to sergeants and for teaching sergeants how to teach these skills to their soldiers. The…

  6. 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)

  7. Temperature dependence of the magnetic volume susceptibility of human breast fat tissue: an NMR study

    NARCIS (Netherlands)

    Sprinkhuizen, S.M.; Bakker, C.J.G.; Ippel, J.H.; Boelens, R.; Viergever, M.A.; Bartels, L.W.

    2012-01-01

    Object Proton resonance frequency shift (PRFS)-based MR thermometry (MRT) is hampered by heat-induced susceptibility changes when applied in tissues containing fat, e.g., the human breast. In order to assess the impact of fat susceptibility changes on PRFS-based MRT during thermal therapy in the

  8. 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…

  9. Learning anatomy enhances spatial ability.

    NARCIS (Netherlands)

    Vorstenbosch, M.A.T.M.; Klaassen, T.P.; Donders, A.R.T.; Kooloos, J.G.M.; Bolhuis, S.M.; Laan, R.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

  10. 76 FR 45594 - Mortgagee Review Board: Administrative Actions

    Science.gov (United States)

    2011-07-29

    .... Orbit Mortgage Company, Coral Springs, FL. 88. Origen Financial, LLC, Southfield, MI. 89. Pacific... Mortgage Banking Center, Inc., Yonkers, NY. 101. Rapid Mortgage Co., Inc., Edinburg, TX. 102. Reaching... Mortgage, LLC, Grand Rapids, MI, 10-1740-MRT. 42. Home Mortgage Corporation, Atlanta, GA, 09-9850-MRT. 43...

  11. 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

  12. 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

  13. 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

  14. 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.)

  15. 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.

  16. Fast electron accumulation and its mechanism in a harmonic trap under ultrahigh vacuum conditions

    International Nuclear Information System (INIS)

    Mohamed, T.; Imao, H.; Mohri, A.; Oshima, N.; Yamazaki, Y.

    2011-01-01

    We present here a fast and efficient electron accumulation in a multiring trap (MRT) in a superconducting solenoid of 5 T. More than 10 10 electrons were accumulated within a fraction of a second for an electron beam in the range of 10 -7 A. The MRT was installed in a cryogenic bore tube cooled down to ∼10 K. Electron accumulation as a function of various parameters such as the beam intensity, the MRT depth, and the MRT length was studied. We succeeded in extracting a consistent picture of the electron accumulation mechanisms, which consist of interactions of the incoming electron beam with the reflected beam and with the electrons trapped in the MRT.

  17. Study protocol: a hybrid effectiveness-implementation trial of Moral Reconation Therapy in the US Veterans Health Administration.

    Science.gov (United States)

    Blonigen, Daniel M; Cucciare, Michael A; Timko, Christine; Smith, Jennifer S; Harnish, Autumn; Kemp, Lakiesha; Rosenthal, Joel; Smelson, David

    2018-03-07

    Moral Reconation Therapy (MRT) is a cognitive-behavioral intervention aimed at reducing risk for criminal recidivism by restructuring antisocial attitudes and cognitions (i.e., "criminogenic thinking"). MRT has empirical support for reducing risk for criminal recidivism among civilian offenders. Recently, a version of MRT was developed for military veterans; however, no randomized controlled trials (RCT) have been conducted with the veteran-specific protocol, and the effectiveness and implementation potential of MRT outside of correctional settings has not been established. Using a Hybrid Type 1 RCT design, this study will test the effectiveness of MRT to reduce risk for criminal recidivism and improve health-related outcomes among justice-involved veterans entering mental health residential treatment at three US Veterans Health Administration (VHA) Medical Centers. Upon admission to the treatment program, justice-involved veterans will complete a baseline assessment, be randomized to usual care (UC) or UC + MRT, and be followed 6 and 12 months post-baseline. A process evaluation will also be conducted to identify barriers and facilitators to implementation of MRT in residential treatment. The primary aim of this study is to evaluate the effectiveness of MRT with justice-involved veterans. If MRT proves effective in this trial, the findings can provide large healthcare systems that serve veterans with an evidence-based intervention for addressing criminogenic thinking among justice-involved adults, as well as guidance on how to facilitate future implementation of MRT in non-correctional settings. This trial is funded by the VA Health Services Research & Development Program (IIR 14-081) and is registered with ClinicalTrials.gov (ID: NCT02524171 ).

  18. 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.

  19. Validation of the mean radiant temperature simulated by the RayMan software in urban environments.

    Science.gov (United States)

    Lee, Hyunjung; Mayer, Helmut

    2016-11-01

    The RayMan software is worldwide applied in investigations on different issues in human-biometeorology. However, only the simulated mean radiant temperature (T mrt ) has been validated so far in a few case studies. They are based on T mrt values, which were experimentally determined in urban environments by use of a globe thermometer or applying the six-directional method. This study analyses previous T mrt validations in a comparative manner. Their results are extended by a recent validation of T mrt in an urban micro-environment in Freiburg (southwest Germany), which can be regarded as relatively heterogeneous due to different shading intensities by tree crowns. In addition, a validation of the physiologically equivalent temperature (PET) simulated by RayMan is conducted for the first time. The validations are based on experimentally determined T mrt and PET values, which were calculated from measured meteorological variables in the daytime of a clear-sky summer day. In total, the validation results show that RayMan is capable of simulating T mrt satisfactorily under relatively homogeneous site conditions. However, the inaccuracy of simulated T mrt is increasing with lower sun elevation and growing heterogeneity of the simulation site. As T mrt represents the meteorological variable that mostly governs PET in the daytime of clear-sky summer days, the accuracy of simulated T mrt is mainly responsible for the accuracy of simulated PET. The T mrt validations result in some recommendations, which concern an update of physical principles applied in the RayMan software to simulate the short- and long-wave radiant flux densities, especially from vertical building walls and tree crowns.

  20. Validation of the mean radiant temperature simulated by the RayMan software in urban environments

    Science.gov (United States)

    Lee, Hyunjung; Mayer, Helmut

    2016-11-01

    The RayMan software is worldwide applied in investigations on different issues in human-biometeorology. However, only the simulated mean radiant temperature ( T mrt) has been validated so far in a few case studies. They are based on T mrt values, which were experimentally determined in urban environments by use of a globe thermometer or applying the six-directional method. This study analyses previous T mrt validations in a comparative manner. Their results are extended by a recent validation of T mrt in an urban micro-environment in Freiburg (southwest Germany), which can be regarded as relatively heterogeneous due to different shading intensities by tree crowns. In addition, a validation of the physiologically equivalent temperature (PET) simulated by RayMan is conducted for the first time. The validations are based on experimentally determined T mrt and PET values, which were calculated from measured meteorological variables in the daytime of a clear-sky summer day. In total, the validation results show that RayMan is capable of simulating T mrt satisfactorily under relatively homogeneous site conditions. However, the inaccuracy of simulated T mrt is increasing with lower sun elevation and growing heterogeneity of the simulation site. As T mrt represents the meteorological variable that mostly governs PET in the daytime of clear-sky summer days, the accuracy of simulated T mrt is mainly responsible for the accuracy of simulated PET. The T mrt validations result in some recommendations, which concern an update of physical principles applied in the RayMan software to simulate the short- and long-wave radiant flux densities, especially from vertical building walls and tree crowns.

  1. 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.

  2. Black coal. Annual report 2002; Steinkohle. Jahresbericht 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-10-01

    An overview is given of the situation of the world energy industry with regard to all energy carriers. Then energy-political conclusions are drawn for German black coal and the resulting prospects are detailed. Finally, some socio-political aspects are considered with regard to German black-coal mining. [German] Es wird eine Uebersicht ueber die Situation der Welt-Energiewirtschaft unter Beruecksichtigung aller Energietraeger gegeben. Anschliessend werden die energiepolitischen Folgerungen fuer die deutsche Steinkohle gezogen, und es werden die resultierenden Perspektiven erlaeutert. Abschliessend werden einige sozialpolitische Aspekte bezueglich des deutschen Steinkohlenbergbaus behandelt.

  3. Processes, spheres of use and importance of sewage sludge disintegration; Verfahren, Einsatzgebiete und Bedeutung der Klaerschlammdesintegration

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, J. [Technische Univ. Braunschweig (Germany). Inst. fuer Siedlungswasserwirtschaft; Technische Univ. Braunschweig (Germany). Inst. fuer Mechanische Verfahrenstechnik

    1999-07-01

    The paper gives an overview of results attained by means of mechanical sludge disintegration methods and compares them with thermal and ozone treatment. The objective is to describe in scientific as well as application-oriented terms the opportunities held and limits to this process step of sludge treatment. (orig.) [German] Im Rahmen des Beitrags wird eine Uebersicht ueber die mit mechanischen Verfahren der Schlammdesintegration erreichten Ergebnisse und ein Vergleich mit der Waerme- und der Ozonbehandlung gegeben. Ziel des Beitrages ist es, die Moeglichkeiten und Grenzen dieses Prozessschrittes der Schlammbehandlung aus wissenschaftlicher wie aus anwendungsorientierter Sicht darzustellen. (orig.)

  4. 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

  5. Effects of first-pass metabolism on metabolite mean residence time determination after oral administration of parent drug.

    Science.gov (United States)

    Chan, K K; Gibaldi, M

    1990-01-01

    Metabolite kinetics after oral drug administration can be determined, without separate metabolite administration, using the concepts of mean residence time (MRT). The MRT of parent drug and metabolite after oral administration of the parent drug, MRTp,p(oral) and MRTm,p(oral), can be calculated directly from the drug and metabolite profiles. The difference between MRTm,p(oral) and MRTp,p(oral), termed Delta MRT, yields an estimate of MRT of metabolite when the metabolite is given as an iv bolus, MRTm,m(iv). The calculation is simple for drugs that are known to undergo, negligible first-pass metabolism. Correction can also be made when extent of first-pass metabolism is known. Ambiguity is encountered, however, when the degree of first-pass metabolism is unknown. When the delta MRT is negative, then first-pass metabolism must be considered. A positive value of delta MRT, on the other hand, is not a definitive indication of the absence of first-pass metabolism. It may occur in the presence or absence of first-pass metabolism. Ignoring the possibility of first-pass metabolism when a positive value of delta MRT occurs may lead to an incorrect estimate of MRTm,m(iv). The estimation error is relatively small, however, when MRTm,m(iv) much greater than MRTp,p(iv), even when first-pass metabolism is extensive. This situation may apply to the administration of a prodrug.

  6. 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.

  7. Manual Resistance versus Conventional Resistance Training: Impact on Strength and Muscular Endurance in Recreationally Trained Men.

    Science.gov (United States)

    Chulvi-Medrano, Iván; Rial, Tamara; Cortell-Tormo, Juan M; Alakhdar, Yasser; La Scala Teixeira, Caue V; Masiá-Tortosa, Laura; Dorgo, Sandor

    2017-09-01

    Manual resistance training (MRT) has been widely used in the field of physical therapy. It has also been used as a strength training method due to the accommodating resistance nature of this modality. The aim of the present study was to compare the effects of an 8-week MRT program on maximum strength and muscular endurance in comparison to conventional resistance training in recreationally trained men. Twenty healthy recreationally trained male subjects were recruited and divided into a MRT training group and a conventional training (CT) group. CT group performed bench press and lat pull-down exercises, and the MRT group performed similar movements with resistance provided by a personal trainer. Both groups completed similar training protocol and training load: 2 training sessions weekly for 3 sets of 8 repetitions at an intensity of 8 to 10 on the perceived exertion scale of 0-10. Initial maximum strength differences were not significant between the groups. Neither group showed significant changes in muscular strength or endurance. Despite the statistically non-significant pre- to post differences, a trend for improvement was observed and effect size (ES) calculations indicated greater magnitude of effects for strength and endurance changes in the MRT group in lat pulldown (g=0.84) compared to CT group. Effectiveness of MRT is similar to CT for improving muscular strength and endurance. MRT can be used as a supplemental or alternative strength training modality for recreationally trained subjects, or be considered by personal trainers especially in low equipped facility conditions.

  8. Present and projected future mean radiant temperature for three European cities

    OpenAIRE

    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

    2017-01-01

    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...

  9. Magnetic resonance tomography of superior vena caval obstruction

    International Nuclear Information System (INIS)

    Weiss, T.; Loddenkemper, R.; Bittner, R.; Sander, B.; Husen-Weiss, E.; Mitsch, E.; Trempenau, B.; Kaiser, D.; Krankenhaus Zehlendorf, Berlin

    1987-01-01

    The potential of magnetic resonance tomography (MRT) to demonstrate the mediastinal veins was evaluated retrospectively in 6 patients with superior vena caval ostruction. In each instance, MRT provided detailed information about the extent of venous obstruction and the precise site of the causative oncological pathology. Transaxial images most clearly and unequivocally depicted obstructed superior vena cavas. MRT was also able to indicate some secondary effects of superior vena cavals obstruction such as slow intravenous flow the latter could be demonstrated by a significant increase of signal intensity within venous structures proximal to the obstruction. Peripheral venous collaterals in the chest wall were better seen with contrast enhanced computed tomography scans. (orig.) [de

  10. The development of material X10CrNiMoTiB 15 15 as structural material for fuel elements; Entwicklung des Werkstoffs X10CrNiMoTiB 15 15 als Strukturmaterial fuer Brennelemente

    Energy Technology Data Exchange (ETDEWEB)

    Bergmann, H.J.; Dietz, W. [Interatom/Siemens-KWU, Bergisch Gladbach (Germany); Ehrlich, K.; Muehling, G.; Schirra, M. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Materialforschung]|[Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Programm Nukleare Sicherheitsforschung

    2003-06-01

    The following report will give a comprehensive assessment of all the results gained during the development of this material. It contains a description of the separate steps for the development, a rather extensive documentation of the examined properties and the most substantial items necessary for a technological application of the material. It also includes a summary of the irradiation experiments and performance tests. With regard to knowledge preservation, the report also wants to give a survey of all the research work for this type of structural material, which might thus be used for general application in reactor technology and also for future studies for advanced reactor systems. (orig.) [German] Ziel des vorliegenden Berichtes war es, eine zusammenfassende Bewertung aller gewonnenen Ergebnisse bei der Entwicklung dieses Werkstoffes vorzunehmen. Sie umfasst eine Darstellung der Entwicklungsschritte, eine eingehende Dokumentation der untersuchten Eigenschaften, die wesentlichen Schwerpunkte bei der Entwicklung geeigneter Werkstofftechnologien und gibt eine Uebersicht ueber die durchgefuehrten Bestrahlungsexperimente und Performancetests. Der Bericht soll im Sinne einer Kompetenzerhaltung eine Uebersicht ueber das Werkstoffkonzept und die erreichten Forschungsergebnisse geben und ihr Anwendung sowohl im Bereich der allgemeinen Kraftwerkstechnik als auch bei moeglichen zukuenftigen Studien ueber fortgeschrittene Reaktorsysteme ermoeglichen. (orig.)

  11. Heterogeneity of Monosymptomatic Resting Tremor in a Prospective Study: Clinical Features, Electrophysiological Test, and Dopamine Transporter Positron Emission Tomography

    Directory of Open Access Journals (Sweden)

    Hua-Guang Zheng

    2015-01-01

    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.

  12. 78 FR 21618 - Mortgagee Review Board: Administrative Actions

    Science.gov (United States)

    2013-04-11

    ... misrepresentative or misleading advertisement or business solicitation to the public. 9. First National Bank of.... Medallion Mortgage Corporation, Arlington, TX [Docket No. 13-1414- MRT] 81. Mercury, Inc., Fairfield, NJ...

  13. Anisotropy and Feedthrough in Magneto-Rayleigh-Taylor Instabilities

    Science.gov (United States)

    Weis, Matthew; Rittersdorf, Ian; Lau, Yue Ying; Zhang, Peng; Gilgenbach, Ronald; Zier, Jacob

    2011-10-01

    The magneto-Rayleigh-Taylor instability (MRT) in a finite slab is studied analytically using the ideal MHD model. The slab may be accelerated by an arbitrary combination of magnetic pressure and fluid pressure, thus allowing an arbitrary degree of anisotropy intrinsic to the acceleration mechanism. The magnetic field in different regions may assume arbitrary magnitude and direction tangential to the interface. In general, MRT retains robust growth if it exists. However, feedthrough may be substantially reduced if there are magnetic fields on both sides of the slab, and if the MRT mode invokes bending of the magnetic field lines. The analytically tractable eigenmode solutions allow an evaluation of the temporal evolution of MRT from random initial surface roughness. Work supported by DoE award DE-SC0002590, NSF award PHY 0903340, and by DoE through Sandia National Lab awards 240985 and 76822 to U. of Michigan. JCZ was supported by an NPSC fellowship through Sandia.

  14. 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...

  15. MR-tomography of the breast - additional informations in chosen cases

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, M.; Semmler, W.

    1987-04-01

    Magnetic resonance tomography (MRT), as the newest imaging procedure in breast diagnosis, has to be compared with the combined use of conventional imaging methods. Many advantages of MRT, which have been emphasized in comparison with mammography, are not superior to the complementary use of mammography and sonography. Additional diagnostic information through MRT is yielded only in the following cases: - differentiation between fibrous fibroadenoma of the elderly woman and circumscribed carcinoma with similar mammographic and sonographic appearances - distinction of stellated fibrous scar tissue from the scirrhotic configuration of the more vascular tumour fibrosis around a carcinoma by using contrast medium MRT - differentiation of periductal fibrosis from inflammatory or carcinomatous ductal and periductal infiltration - better delineation of fat or silicon implants. Finally, a significant advantage of mammography over all other imaging methods should be pointed out: the detailed visualization of microcalcifications for the early diagnosis of breast carcinoma.

  16. 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.

  17. 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)

  18. Characteristics of the mean radiant temperature in high latitude cities--implications for sensitive climate planning applications.

    Science.gov (United States)

    Lindberg, Fredrik; Holmer, Björn; Thorsson, Sofia; Rayner, David

    2014-07-01

    Knowledge of how the mean radiant temperature (T mrt ) is affected by factors such as location, climate and urban setting contributes to the practice of climate sensitive planning. This paper examines how T mrt varies within an urban setting and how it is influenced by cloudiness. In addition, variations of T mrt in three high latitude cities are investigated in order to analyse the impact of geographical context and climate conditions. Results showed large spatial variations between sunlit and shaded areas during clear weather conditions, with the highest values of T mrt close to sunlit walls and the lowest values in the areas shaded by buildings and vegetation. As cloudiness increases, the spatial pattern is altered and the differences are reduced. The highest T mrt under cloudy conditions is instead found in open areas where the proportion of shortwave diffuse radiation from the sky vault is high. A regional comparison between three Swedish coastal cities showed that T mrt during summer is similar regardless of latitudinal location. On the other hand, large differences in T mrt during winter were found. Shadows, both from buildings and vegetation are the most effective measure to reduce extreme values of T mrt. However, extensive areas of shadow are usually not desired within outdoor urban environments at high latitude cities. One solution is to create diverse outdoor urban spaces in terms of shadow and also ventilation. This would provide individuals with access to a choice of thermal environments which they can use to assist their thermal regulation, based on personal needs and desires.

  19. Immersive virtual reality platform for medical training: a "killer-application".

    Science.gov (United States)

    2000-01-01

    The Medical Readiness Trainer (MRT) integrates fully immersive Virtual Reality (VR), highly advanced medical simulation technologies, and medical data to enable unprecedented medical education and training. The flexibility offered by the MRT environment serves as a practical teaching tool today and in the near future the will serve as an ideal vehicle for facilitating the transition to the next level of medical practice, i.e., telepresence and next generation Internet-based collaborative learning.

  20. 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)

  1. The Effect of Visual-Spatial Ability on the Learning of Robot-Assisted Surgical Skills.

    Science.gov (United States)

    Abe, Takashige; Raison, Nicholas; Shinohara, Nobuo; Shamim Khan, M; Ahmed, Kamran; Dasgupta, Prokar

    The aim of this study was to determine the correlation of visual-spatial ability with progression along the learning curve for robotic surgical skills training. A total of 21 novice participants were recruited. All participants completed a training program consisting of 5 training sessions of 30 minutes of virtual reality (VR) simulation and 30 minutes of dry laboratory training. The VR simulation part was the subject of the present study. During VR simulation training, participants performed the basic skill exercises of Camera Targeting 1, Pick and Place, and Peg Board 1 followed by advanced skill exercises of Suture Sponge 1 and Thread the Rings. The visual-spatial ability was assessed using a mental rotation test (MRT). Pearson correlation coefficients were used to assess the relationship between the MRT score and simulator score for the aforementioned 5 tasks. Student t test was used to compare the simulator score between high- and low-MRT score groups. A median MRT score of 26/40 (range: 13-38) was observed. Approximately 19 participants completed the full curriculum but 2 did not complete "Thread the Rings" during the study period. A significant correlation was observed between the MRT score and simulator score only in "Suture Sponge 1" over the first 3 attempts (first: r = 0.584, p = 0.0054; second: r = 0.443, p = 0.0443; third: r = 0.4458, p = 0.0428). After the third attempt, this significant correlation was lost. Comparison of the score for "Suture Sponge 1" between the high-MRT and low-MRT scoring participants divided by a median MRT score of 26 also showed a significant difference in the score until the third trial. Our observations suggest that the spatial cognitive ability influences the initial learning of robotic suturing skills. Further studies are necessary to verify the usefulness of an individual's spatial ability to tailor the surgical training program. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Medical training therapy in lumbar syndromes.

    Science.gov (United States)

    Broll-Zeitvogel, E; Grifka, J; Bauer, J; Roths, P H; Degryse, P

    1999-11-01

    Chronic low back pain can be considered to be one of the most frequently treated and most costly diseases in modern industrial societies. Dysfunctions and imbalances of the spine-supporting muscles increase the risk of low back pain. Consequently preventive treatment and rehabilitation have to aim at preserving and restoring the full capacity of the spine-supporting muscles as well as training coordination and spine-friendly behaviour. In addition to various measures of pain therapy, physiotherapeutic treatment including neuro-physiotherapy, physical treatment (eg electrotherapy), balneotherapy and supportive behavioural training, medical rehabilitation therapy (MRT) ranks among the most effective ways of treating low back pain. MRT applies guidelines and methods of exercise methodology within medically indicated programmes of preventive treatment and rehabilitation. Various objectives of MRT are outlined with special regard to the stages of MRT treatment, emphasizing positive adaptation of the neuro-muscular system in the course of rehabilitation. Physicians are responsible for MRT diagnosis and control. Taking into account the base disorder and the progress of therapy physiotherapists and the physicians in charge determine MRT objectives and treatment strategies.

  3. [Medical training therapy in lumbar syndromes].

    Science.gov (United States)

    Broll-Zeitvogel, E; Grifka, J; Bauer, J; Roths, P H; Degryse, P

    1999-11-01

    Chronic low back pain can be considered to be one of the most frequently treated and most costly diseases in modern industrial societies. Dysfunctions and imbalances of the spine-supporting muscles increase the risk of low back pain. Consequently preventive treatment and rehabilitation have to aim at preserving and restoring the full capacity of the spine-supporting muscles as well as training coordination and spine-friendly behaviour. In addition to various measures of pain therapy, physiotherapeutic treatment including neuro-physiotherapy, physical treatment (eg electrotherapy), balneotherapy and supportive behavioural training, medical rehabilitation therapy (MRT) ranks among the most effective ways of treating low back pain. MRT applies guidelines and methods of exercise methodology within medically indicated programmes of preventive treatment and rehabilitation. Various objectives of MRT are outlined with special regard to the stages of MRT treatment, emphasizing positive adaptation of the neuro-muscular system in the course of rehabilitation. Physicians are responsible for MRT diagnosis and control. Taking into account the base disorder and the progress of therapy physiotherapists and the physicians in charge determine MRT objectives and treatment strategies.

  4. Validation of MR thermometry: method for temperature probe sensor registration accuracy in head and neck phantoms.

    Science.gov (United States)

    Tarasek, Matthew R; Pellicer, Ruben; Hofstetter, Lorne W; Numan, Wouter C M; Bakker, Jurriaan F; Kotek, Gyula; Togni, Paolo; Verhaart, René F; Fiveland, Eric W; Houston, Gavin C; van Rhoon, Gerard C; Paulides, Margarethus Marius; Yeo, Desmond Teck Beng

    2014-03-01

    Magnetic resonance thermometry (MRT) is an attractive means to non-invasively monitor in vivo temperature during head and neck hyperthermia treatments because it can provide multi-dimensional temperature information with high spatial resolution over large regions of interest. However, validation of MRT measurements in a head and neck clinical set-up is crucial to ensure the temperature maps are accurate. Here we demonstrate a unique approach for temperature probe sensor localisation in head and neck hyperthermia test phantoms. We characterise the proton resonance frequency shift temperature coefficient and validate MRT measurements in an oil-gel phantom by applying a combination of MR imaging and 3D spline fitting for accurate probe localisation. We also investigate how uncertainties in both the probe localisation and the proton resonance frequency shift (PRFS) thermal coefficient affect the registration of fibre-optic reference temperature probe and MRT readings. The method provides a two-fold advantage of sensor localisation and PRFS thermal coefficient calibration. We provide experimental data for two distinct head and neck phantoms showing the significance of this method as it mitigates temperature probe localisation errors and thereby increases accuracy of MRT validation results. The techniques presented here may be used to simplify calibration experiments that use an interstitial heating device, or any heating method that provides rapid and spatially localised heat distributions. Overall, the experimental verification of the data registration and PRFS thermal coefficient calibration technique provides a useful benchmarking method to maximise MRT accuracy in any similar context.

  5. 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.

  6. 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.

  7. Multiple-relaxation-time lattice Boltzmann simulation for flow, mass transfer, and adsorption in porous media

    Science.gov (United States)

    Ma, Qiang; Chen, Zhenqian; Liu, Hao

    2017-07-01

    In this paper, to predict the dynamics behaviors of flow and mass transfer with adsorption phenomena in porous media at the representative elementary volume (REV) scale, a multiple-relaxation-time (MRT) lattice Boltzmann (LB) model for the convection-diffusion equation is developed to solve the transfer problem with an unsteady source term in porous media. Utilizing the Chapman-Enskog analysis, the modified MRT-LB model can recover the macroscopic governing equations at the REV scale. The coupled MRT-LB model for momentum and mass transfer is validated by comparing with the finite-difference method and the analytical solution. Moreover, using the MRT-LB method coupled with the linear driving force model, the fluid transfer and adsorption behaviors of the carbon dioxide in a porous fixed bed are explored. The breakthrough curve of adsorption from MRT-LB simulation is compared with the experimental data and the finite-element solution, and the transient concentration distributions of the carbon dioxide along the porous fixed bed are elaborated upon in detail. In addition, the MRT-LB simulation results show that the appearance time of the breakthrough point in the breakthrough curve is advanced as the mass transfer resistance in the linear driving force model increases; however, the saturation point is prolonged inversely.

  8. Magnetic resonance therapy for knee osteoarthritis: a randomized, double blind placebo controlled trial.

    Science.gov (United States)

    Gökşen, Nurgül; Çaliş, Mustafa; Doğan, Serap; Çaliş, Havva T; Özgöçmen, Salih

    2016-08-01

    Therapeutic nuclear magnetic resonance therapy (MRT) works based on the electromagnetic fields. To investigate efficacy of MRT in knee osteoarthritis (OA). Prospective, randomized, double-blind, placebo controlled trial. Outpatient clinic, university hospital. Patients who had mild to moderate knee OA at a single knee joint and between 30-75-years-old were randomized by blinded chip cards (1:1). The treatment group received ten sessions of one hour daily MRT, controls received placebo MRT. All patients underwent clinical examination at baseline, after 2 weeks, and 12 weeks. Imaging included blindly assessed ultrasonography and magnetic resonance (MR) of the knee. Ninety-seven patients completed the study. Both groups improved significantly but the average change from baseline in outcome parameters was similar in MRT group (on VAS-pain,-2.6; WOMAC-pain, -2.09; WOMAC-stiffness, -1.81; WOMAC-physical, -1.96) compared to placebo after two weeks (VAS-pain,-1.6; WOMAC-pain, -1.91; WOMAC-stiffness, -1.27; WOMAC-physical, -1.54). Also changes were quite similar at the 12th week after the treatment. SF-36 components at 12th week improved but changes were not significant. Imaging arm also failed to show significant differences between groups in terms of cartilage thickness on US and MR scores. No adverse events were recorded. MRT is safe, but not superior to placebo in terms of improvement in clinical or imaging parameters after a 10-day course of treatment in mild to moderate knee OA. The present study does not promote use of a 10-day course of MRT in mild to moderate knee OA.

  9. 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.

  10. 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.

  11. Efficiencies of different flue gas purification systems in waste incinerators. Experimental report; Untersuchungen zur Effizienz von unterschiedlichen Systemen zur Rauchgasreinigung bei Muellverbrennungsanlagen. Untersuchungsbericht

    Energy Technology Data Exchange (ETDEWEB)

    Berghoff, R. (comp.)

    2001-07-01

    This investigation was carried out on behalf of the Environmental Office of the state of Nordrhein-Westfalen. Apart from the current and projected exhaust purification systems, also three exemplary systems were analyzed from the ecological and economic point of view. Effects on pollutant freights were established in consideration of energy consumption and the specific cost of waste treatment for each technology. [German] Das konkrete Ziel dieser vom Landesumweltamt NRW vergebenen Untersuchung war es, neben einer Uebersicht ueber die zzt. eingesetzten und auch geplanten Abgasreinigungssysteme (RGR) bei Muellverbrennungsanlagen, die Vor- und die Nachteile von 3 beispielhaft ausgewaehlten Systemen in einem oekologischen und oekonomischen Vergleich knapp und begrenzt darstellen zu lassen. Als Ergebnis wurden die Auswirkungen der unterschiedlichen Verfahren auf die Frachten der emittierten Schadstoffe unter Beruecksichtigung der unterschiedlichen Energieverbraeuche ermittelt und dargestellt. Darueber hinaus wurden die spezifischen Muellbehandlungskosten bei den jeweiligen Gasreinigungstechniken errechnet. (orig.)

  12. Contrast media-associated nephrotoxicity - pathogenenesis and prevention; Kontrastmittelnephropathie - Pathogenese und Praevention

    Energy Technology Data Exchange (ETDEWEB)

    Erley, C.M. [Abt. Innere Medizin III, Sektion Nieren- und Hochdruckkrankheiten, Tuebingen Univ. (Germany); Duda, S.H. [Tuebingen Univ. (Germany). Abt. fuer Radiologische Diagnostik

    1997-07-01

    Contrast media-associated nephrotoxicity continues to be a relevant cause of acute renal failure, especially in patients with pre-existing renal insufficiency. Alterations in renal hemodynamics and direct tubular toxicity by contrast media are the primary factors believed to be responsible for contrast media-associated nephrotoxicity. We review recent insights into the pathogenesis of this complication and summarize prophylactic strategies focussing on hydration, vasoactive pharmacological agents, and prophylactic hemodialysis`. (orig.) [Deutsch] Die Kontrastmittelnephropathie (KMN) stellt insbesondere bei Patienten mit eingeschraenkter Nierenfunktion ein erhebliches medizinisches Problem dar. Die Genese der KMN ist nach wie vor nicht eindeutig geklaert. Neben haemodynamischen Veraenderungen durch die Kontrastmittel spielen tubulotoxische Schaeden eine grosse Rolle. Die vorliegende Uebersicht beschreibt die zur Zeit bekannten pathophysiologischen Vorgaenge bei der KMN und die zur Zeit angewendeten Praeventivmassnahmen. (orig.)

  13. Status report 1993-1997 on solar energy research; Statusbericht 1993-1997 Schwerpunkt `Solarenergieforschung`

    Energy Technology Data Exchange (ETDEWEB)

    Fuhs, W.; Lux-Steiner, M.; Tributsch, H.; Willig, F.

    1998-09-01

    Solar energy research at the Berlin Hahn-Meitner-Institut (HMI) comprises the following subjects: (a) Silicon thin film solar cells; (b) High-absorption intermediate semiconductors; (c) Photoelectrochemistry and photocatalysis; (d) Injection-type solar cells; (e) Interdisciplinary projects, accompanying materials research and basic research. The 1993 - 1997 status report presents a detailed outline of the projects. [Deutsch] Im Zentrum der Solarenergieforschung des Hahn-Meitner-Instituts (HMI) stehen die folgenden Vorhaben: (a) Duennschichtsolarzellen aus Silizium; (b) Hochabsorbierende Verbindungsleiter; (c) Photoelectrochemie und Photokatalyse; (d) Injektionssolarzellen; (e) Querschnittsaufgaben, begleitende Material- und Grundlagenforschung. Diese Vorhaben werden von Projekten verschiedener Abteilungen getragen. Der vorliegende Statusbericht 1993-1997 gibt eine detaillierte Uebersicht ueber die oben genannten Projekte. (AKF)

  14. Measurements of vertical displacement of power station buildings using an automatic stationary hydrostatic measuring system; Anwendung des automatisierten stationaeren hydrostatischen Messsystems fuer die Aufnahme der Vertikalverschiebungen an den Objekten der Kern- und Waermekraftwerke

    Energy Technology Data Exchange (ETDEWEB)

    Lechner, J. [Forschungsinstitut fuer Geodaesie, Topographie und Kartographie, Zdiby (Czechoslovakia)

    1996-12-31

    The contribution describes hydrostatic stationary measuring systems for measurements of height variations of a turbine unit. The measuring system developed at the research institute and the algorithms for calibration, measurement and evaluation are presented. Measurements were made on a 500 MW turbogenerator unit at different states of operation. (orig.) [Deutsch] Der Beitrag enthaelt eine kurze Uebersicht ueber die hydrostatischen stationaeren Messsysteme fuer das Gebiet der Messung der Hoehenaenderung eines Grossturbinentisches. Es wird das automatische stationaere hydrostatische Messsystem, das im Forschungsinstitut entwickelt wurde, der Algorithmus der Kalibrierung, der Messung und der Auswertung der Messergebnisse vorgestellt. Es wird das Messergebnis der Vertikalverschiebungen der Konstruktion des Turbogenerators mit der Leistung 500 Megawatt bei seinem verschiedenen Betriebszustand angefuehrt. (orig.)

  15. Security and supervision in the telecommunications sector; Sicherheit und Ueberwachung in der Telekommunikation

    Energy Technology Data Exchange (ETDEWEB)

    Fiebig, T.H. [HanseNet Telekommunikation GmbH, Hamburg (Germany)

    1998-03-09

    The contribution summarizes and interprets the laws and regulatory provisions relating to the telecommunications sector in Germany and intended to warrant security and surveillance of installations and services, addressing both technical aspects and legal requirements, which might become of interest in connection with transmission services that might be offered in future by electric power network operators, as a possible, new operational area and expansion of scope of services. (CB) [Deutsch] Der Beitrag gibt eine zusammenfassende und interpretierende Uebersicht ueber die derzeit gueltigen Gesetze und untergeordneten Regelungen, die Sicherheit und Ueberwachungskompetenzen im Telekommunikations-Sektor in Deutschland gewaehrleisten sollen. Es geht um technische Schutzmassnahmen und rechtliche Sicherheitsanforderungen, die im Hinblick auf zur Zeit diskutierte und moegliche kuenftige Dienstleistungen in diesem Bereich seitens der Betreiber von Netzen fuer die Stromuebertragung von Interesse sein koennen. (CB)

  16. Black coal. Annual report 1996; Steinkohle. Jahresbericht 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    An overview is given of the situation of the world energy industry with regard to all energy carriers. Then energy-political conclusions are drawn for German black coal and the resulting prospects are detailed. Finally, some socio-political aspects are considered with regard to German black-coal mining: Workforce policy, tariff policy, social security and social safeguards for the adaptation process. (orig.) [Deutsch] Es wird eine Uebersicht ueber die Situation der Welt-Energiewirtschaft unter Beruecksichtigung aller Energietraeger gegeben. Anschliessend werden die energiepolitischen Folgerungen fuer die deutsche Steinkohle gezogen, und es werden die resultierenden Perspektiven erlaeutert. Abschliessend werden einige sozialpolitische Aspekte bezueglich des deutschen Steinkohlenbergbaus behandelt: Belegschaftspolitik, Tarifpolitik, soziale Sicherheit und soziale Absicherung des Anpassungsprozesses. (orig.)

  17. 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

  18. 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

  19. The application of matrix rhythm therapy as a new clinical modality in burn physiotherapy programmes.

    Science.gov (United States)

    Sarı, Zübeyir; Polat, Mine Gülden; Özgül, Bahar; Aydoğdu, Onur; Camcıoğlu, Burcu; Acar, Ahmet Hakan; Yurdalan, Saadet Ufuk

    2014-08-01

    The aim of the present study was to investigate the use of matrix rhythm therapy (MRT) as one of the electrotherapeutic modalities in clinics. This study was carried out in the Burn and Wound Treatment Department of Dr. Lütfi Kırdar Kartal Education and Research Hospital in Istanbul between October 2010 and August 2011. A treatment protocol including whirlpool, MRT and exercise was applied to a group of patients who had burn injury of upper extremity. The evaluation of each patient included assessment of pain, range of motion, muscle strength, skin flexibility and sensory function at pre- and post-treatment. There was no significant difference in values of pain, muscle strength and flexibility between pre- and post-treatment assessments (p>0.05). A significant increase was found in the range of motion and sensory function at pre-treatment according to post-treatment (p<0.01). The usage of MRT in order to maintain and improve the range of motion and to minimise the development of scar tissue was investigated in this study. We suggest conducting randomised controlled studies that carry out a comparison of the MRT with other treatment modalities with more cases and investigate the long-term effects of MRT. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  20. Developing a methodology for estimating the drag in front-crawl swimming at various velocities.

    Science.gov (United States)

    Narita, Kenzo; Nakashima, Motomu; Takagi, Hideki

    2017-03-21

    We aimed to develop a new method for evaluating the drag in front-crawl swimming at various velocities and at full stroke. In this study, we introduce the basic principle and apparatus for the new method, which estimates the drag in swimming using measured values of residual thrust (MRT). Furthermore, we applied the MRT to evaluate the active drag (Da) and compared it with the passive drag (Dp) measured for the same swimmers. Da was estimated in five-stages for velocities ranging from 1.0 to 1.4ms -1 ; Dp was measured at flow velocities ranging from 0.9 to 1.5ms -1 at intervals of 0.1ms -1 . The variability in the values of Da at MRT was also investigated for two swimmers. According to the results, Da (Da=32.3 v 3.3 , N=30, R 2 =0.90) was larger than Dp (Dp=23.5 v 2.0 , N=42, R 2 =0.89) and the variability in Da for the two swimmers was 6.5% and 3.0%. MRT can be used to evaluate Da at various velocities and is special in that it can be applied to various swimming styles. Therefore, the evaluation of drag in swimming using MRT is expected to play a role in establishing the fundamental data for swimming. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. 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 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.

  2. '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

  3. 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.

  4. Prevalence of Bovine Brucellosis in Organized Dairy Farms, Using Milk ELISA, in Quetta City, Balochistan, Pakistan

    Directory of Open Access Journals (Sweden)

    Muhammad Shafee

    2011-01-01

    Full Text Available A total of 200 milk samples from cattle (=86 and buffalo (=114 were evaluated using milk ring test (MRT and indirect enzyme-linked immunosorbent assay (i-ELISA. The overall prevalence was found to be 3% and 8.5% in cattle and buffaloes using MRT and i-ELISA, respectively. The prevalence was 4.6% and 1.7% in cattle and buffalo using MRT, respectively, while i-ELISA exhibited 20% and 0% in cattle and buffalo, respectively. The prevalence was higher in government dairy farm, compared to privately owned dairy farm. This paper points out an alarming situation in the target area with respect to the public health significance.

  5. Calculations of first passage time of delayed tree-like networks

    Science.gov (United States)

    Wang, Shuai; Sun, Weigang; Zheng, Song

    2015-10-01

    In this paper, we study random walks in a family of delayed tree-like networks controlled by two network parameters, where an immobile trap is located at the initial node. The novel feature of this family of networks is that the existing nodes have a time delay to give birth to new nodes. By the self-similar network structure, we obtain exact solutions of three types of first passage time (FPT) measuring the efficiency of random walks, which includes the mean receiving time (MRT), mean sending time (MST) and mean first passage time (MFPT). The obtained results show that the MRT, MST and MFPT increase with the network parameters. We further show that the values of MRT, MST and MFPT are much shorter than the nondelayed counterpart, implying that the efficiency of random walks in delayed trees is much higher.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. DNA damage and repair kinetics after microbeam radiation therapy emulation in living cells using monoenergetic synchrotron X-ray microbeams.

    Science.gov (United States)

    Sprung, Carl N; Cholewa, Marian; Usami, Noriko; Kobayashi, Katsumi; Crosbie, Jeffrey C

    2011-07-01

    A novel synchrotron-based approach, known as microbeam radiation therapy (MRT), currently shows considerable promise in increased tumour control and reduced normal tissue damage compared with conventional radiotherapy. Different microbeam widths and separations were investigated using a controlled cell culture system and monoenergetic (5.35 keV) synchrotron X-rays in order to gain further insight into the underlying cellular response to MRT. DNA damage and repair was measured using fluorescent antibodies against phosphorylated histone H2AX, which also allowed us to verify the exact location of the microbeam path. Beam dimensions that reproduced promising MRT strategies were used to identify useful methods to study the underpinnings of MRT. These studies include the investigation of different spatial configurations on bystander effects. γH2AX foci number were robustly induced in directly hit cells and considerable DNA double-strand break repair occurred by 12 h post-10 Gy irradiation; however, many cells had some γH2AX foci at the 12 h time point. γH2AX foci at later time points did not directly correspond with the targeted regions suggesting cell movement or bystander effects as a potential mechanism for MRT effectiveness. Partial irradiation of single nuclei was also investigated and in most cases γH2AX foci were not observed outside the field of irradiation within 1 h after irradiation indicating very little chromatin movement in this time frame. These studies contribute to the understanding of the fundamental radiation biology relating to the MRT response, a potential new therapy for cancer patients.

  12. Diagnostic possibilities following implantation of carbon-fibre-reinforced plastic (CFRP) total hip arthroplasty; Moeglichkeiten der bildgebenden Darstellung eines Hueftendoprothesenschaftes aus Kohlenstofffaserverbundwerkstoff (CFK)

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, T.; Reichel, H.; Birke, A.; Hein, W. [Univ. Halle-Wittenberg (Germany). Klinik und Poliklinik fuer Orthopaedie; Alter, C.; Spielmann, R.P. [Univ. Halle-Wittenberg (Germany). Klinik fuer Diagnostische Radiologie

    1998-03-01

    Introduction: There are many problems in the radiological diagnosis of aseptic loosening in total hip arthroplasty. Computed tomography (CT) and magnetic resonance tomography (MRT) are not usable for metallic implants (stainless steel, cobalt alloy, titanium alloy). Material and Methods: From April 1993 to December 1993 15 CFRP non-cemented hip prostheses have been implanted. In a prospective clinical study plane radiographs, CT and MRT have been analysed. Results: Three stems were revised (1 femoral fracture, 1 severe thigh pain, 1 aseptic loosening). CFRP are not visible in plane radiographs. There was a complete (two-third of the cases) or nearly complete (one-third of the cases) small sclerotic interface between the prosthesis and the bone, these were apparent in CT and MRT in stable implant cases and did not have any clinical correlations. Discussion: The small sclerotic interface is quite different in comparison to so called `Reactive lines`. In one case of aseptic loosening there was an interposition of soft tissue between prothesis and bone in MRT and CT. CFRP inaugurates new diagnostic possibilities in aseptic loosening of hip prosthesis and in tumour surgery too. (orig.) [Deutsch] Einleitung: Die Diagnostik der aseptischen Endoprothesenlockerung bereitet mitunter im Routineroentgenbild erhebliche Probleme. Bei den zumeist verwendeten Implantaten (Material: rostfreier Stahl, Titan- oder Kobaltbasislegierungen) sind Magnetresonanztomographie (MRT) und Computertomographie (CT) wegen grenzschichtnaher Artefakte nicht einsetzbar. Material und Methode: Im Rahmen einer klinischen Studie wurden zwischen April 1993 und Dezember 1993 15 Hueftendoprothesenschaefte aus Kohlenstofffaserverbundwerkstoff (CFK) zementfrei implantiert und prospektiv klinisch, radiologisch und mit MRT/CT untersucht. Ergebnisse: Drei Schaefte mussten im Untersuchungszeitraum entfernt werden (1 Femurfraktur, 1 Oberschenkelschmerz, 1 aseptische Lockerung). Radiologisch imponiert die

  13. Comparison of different methods of estimating the mean radiant temperature in outdoor thermal comfort studies.

    Science.gov (United States)

    Krüger, E L; Minella, F O; Matzarakis, A

    2014-10-01

    Correlations between outdoor thermal indices and the calculated or measured mean radiant temperature T(mrt) are in general of high importance because of the combined effect on human energy balance in outdoor spaces. The most accurate way to determine T(mrt) is by means of integral radiation measurements, i.e. measuring the short- and long-wave radiation from six directions using pyranometers and pyrgeometers, an expensive and not always an easily available procedure. Some studies use globe thermometers combined with air temperature and wind speed sensors. An alternative way to determine T(mrt) is based on output from the RayMan model from measured data of incoming global radiation and morphological features of the monitoring site in particular sky view factor (SVF) data. The purpose of this paper is to compare different methods to assess the mean radiant temperature T(mrt) in terms of differences to a reference condition (T(mrt) calculated from field measurements) and to resulting outdoor comfort levels expressed as PET and UTCI values. The T(mrt) obtained from field measurements is a combination of air temperature, wind speed and globe temperature data according to the forced ventilation formula of ISO 7726 for data collected in Glasgow, UK. Four different methods were used in the RayMan model for T(mrt) calculations: input data consisting exclusively of data measured at urban sites; urban data excluding solar radiation, estimated SVF data and solar radiation data measured at a rural site; urban data excluding solar radiation with SVF data for each site; urban data excluding solar radiation and including solar radiation at the rural site taking no account of SVF information. Results show that all methods overestimate T(mrt) when compared to ISO calculations. Correlations were found to be significant for the first method and lower for the other three. Results in terms of comfort (PET, UTCI) suggest that reasonable estimates could be made based on global radiation

  14. Revisiting the Effectiveness of African Economic Integration. A Meta-Analytic Review and Comparative Estimation Methods

    DEFF Research Database (Denmark)

    Afesorgbor, Sylvanus Kwaku

    , these studies failed to account for multilateral resistance term (MRT). The omission of the MRT contributes to biased estimates for standard variables in the gravity model. This bias is reflected in parameters of these previous studies. Secondly, there is significant proportion of zero flows in developing...... to Poisson Pseudo Maximum Likelihood (PPML). Using panel data on trade flows from 1980 to 2006 for 47 African countries, we estimate the gravity model for the five major RTAs on the Africa continent. We find that although there is general positive impact of African RTAs, impacts are highly sensitive...

  15. 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.)

  16. 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.

  17. 'n ope brief aan Dorian Gray en 'n peiling van die Afrikaanse ...

    African Journals Online (AJOL)

    19 Mrt. 2018 ... kritieser lesers (nie net vriende, Instagram-ondersteuners en kollegas nie) en 'n in- tensiewer ontginning van beskikbare toetsterreine. Het hy ooit gedigte voorgelê vir. NB-Uitgewers se Nuwe stemme-reeks? Sterk debutante soos Ilse van Staden, Bernard. Odendaal, Ronelda Kamfer, Loftus Marais, Hennie ...

  18. Christo Beyers-Sy Tydgenote en Geskrifte

    African Journals Online (AJOL)

    9 Mrt. 1974 ... leagues in Johannesburg honoured the memory of this great surgeon by naming the medical branch of the faculty of medicine of the South African Academy ..... Hy skryf: 'The graft took perfectly, the ram was re- juvenated and could be used again by the farmer'. Die feit dat Beyers en sy ou skoolvriend, J. J. ...

  19. 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.

  20. Influence of ground surface characteristics on the mean radiant temperature in urban areas.

    Science.gov (United States)

    Lindberg, Fredrik; Onomura, Shiho; Grimmond, C S B

    2016-09-01

    The effect of variations in land cover on mean radiant temperature (T mrt ) is explored through a simple scheme developed within the radiation model SOLWEIG. Outgoing longwave radiation is parameterised using surface temperature observations on a grass and an asphalt surface, whereas outgoing shortwave radiation is modelled through variations in albedo for the different surfaces. The influence of ground surface materials on T mrt is small compared to the effects of shadowing. Nevertheless, altering ground surface materials could contribute to a reduction in T mrt to reduce the radiant load during heat-wave episodes in locations where shadowing is not an option. Evaluation of the new scheme suggests that despite its simplicity it can simulate the outgoing fluxes well, especially during sunny conditions. However, it underestimates at night and in shadowed locations. One grass surface used to develop the parameterisation, with very different characteristics compared to an evaluation grass site, caused T mrt to be underestimated. The implications of using high temporal resolution (e.g. 15 minutes) meteorological forcing data under partly cloudy conditions are demonstrated even for fairly proximal sites.

  1. A statistical downscaling algorithm for thermal comfort applications

    Science.gov (United States)

    Rayner, David; Lindberg, Fredrik; Thorsson, Sofia; Holmer, Björn

    2015-11-01

    We describe a new two-step modeling framework for investigating the impact of climate change on human comfort in outdoor urban environments. In the first step, climate change scenarios for air temperature and solar radiation (global, diffuse, direct components) are created using a change-factor algorithm. The change factors are calculated by comparing ranked daily regional climate model outputs for a future-period and a present-day period, and then changes consistent with these daily change factors are applied to historical hourly climate observations. In the second step, the mean-radiant-temperature ( T mrt) is calculated using the SOLWEIG (SOlar and LongWave Environmental Irradiance Geometry) model. T mrt, which describes the radiant heat exchange between a person and their surroundings, is one of the most important meteorologically derived parameters governing human energy balance and outdoor thermal comfort, especially during warm and sunny days. We demonstrate that change factors can be applied independently to maximum air temperature and daily global solar radiation, and show that the outputs from the algorithm, when aggregated to daily values, are consistent with the driving regional climate model. Finally, we demonstrate how to obtain quantitative information from the scenarios regarding the potential impact of climate change on outdoor thermal comfort, by calculating changes in the distribution of hourly summer day-time T mrt and changes in the number of hours with T mrt >55 °C.

  2. 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.

  3. Is Longpunksie-aspirasie''n Onskuldige Prosedure?

    African Journals Online (AJOL)

    23 Mrt. 1974 ... kan gebruik word vir uitkenning van Klebsiella pneu- moniae en H. influenzae tipe-b; (iv) die teenwoordigheid van onvermoede pleuraalvog kan soms vasgesteI word; en. (v) ongewone siekteverwekkers soos fungi, parasiete en seldsame mikroorganismes, waarvoor spesifieke behande- ling benodig word ...

  4. RESENSIES / REVIEWS

    African Journals Online (AJOL)

    19 Mrt. 2018 ... die boek Spreuke, die Samaritaanse vrou uit die Johannes-evangelie; vroue uit die literatuur soos Dulcinea uit Don Quijote;. 'n vrou as lewensmaat, ook 'n moeder en 'n dogter. Verder word die tema van ouderdom en sterwe in hierdie afdeling. 16_Resensies Reviews.indd 210. 2018/03/19 02:31:04 PM ...

  5. Rhabdomyolysis in DOMS

    International Nuclear Information System (INIS)

    Martinez Carsi, C.; Ruiz Hernandez, G.; Sanchez Marchori, C.; Munoz Moliner, J.

    1999-01-01

    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.) [de

  6. Tienie du Plessis: maker van boeke

    African Journals Online (AJOL)

    28 Mrt. 2016 ... huldeblyk. Na 'n heupoperasie sterf hy aan 'n hartaanval op. Vrydagoggend 9 Oktober 2015 in die Little Company of Mary Hospitaal in Pretoria. Ons het mekaar leer ken deur sy betrokkenheid by die uitgewery Taurus en. Stet, die kortstondige little magazine van die 1980's. Hy het Taurus se boeke ontwerp.

  7. Pretest and Posttest Results of the First KEEP Program Year. Technical Report #5.

    Science.gov (United States)

    Gallimore, Ronald; And Others

    This report presents a pre- and posttest evaluation of the first program year of the Kamehameha Early Education Program (KEEP). Each of the 28 children in the KEEP kindergarten class received three tests: the Wechsler Preschool and Primary Scale of Intelligence (WPPSI), the Metropolitan Readiness Test (MRT), and the Standard English Repetition…

  8. Pre- and Post-Test Results of KEEP Class 2: 1973-74. Technical Report #40.

    Science.gov (United States)

    Fox, Candy

    This report presents the pre-and posttest results for the kindergarten year of the Kamehameha Early Education Program (KEEP) Class 2, 1973-1974. Results are presented for the Wechsler Preschool and Primary Scale of Intelligence (WPPSI), the Metropolitan Readiness Test (MRT), and the Standard English Repetition Test (SERT). Comparisons are made…

  9. An Evaluation of Standardized Tests as Tools for the Measurement of Language Development.

    Science.gov (United States)

    Roberts, Elsa

    Four tests--PPVT, ITPA, MRT, WPPSI--commonly used to measure language development in young children are evaluated by four criteria: (1) what development aspects do they claim to tap; (2) what do they actually tap; (3) what linguistic knowledge is presupposed; (4) what special problems face a non-standard English speaker. These tests are considered…

  10. 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.)

  11. 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

  12. Magnetic resonance thermometry at 7T for real-time monitoring and correction of ultrasound induced mild hyperthermia.

    Directory of Open Access Journals (Sweden)

    Brett Z Fite

    Full Text Available While Magnetic Resonance Thermometry (MRT has been extensively utilized for non-invasive temperature measurement, there is limited data on the use of high field (≥7T scanners for this purpose. MR-guided Focused Ultrasound (MRgFUS is a promising non-invasive method for localized hyperthermia and drug delivery. MRT based on the temperature sensitivity of the proton resonance frequency (PRF has been implemented in both a tissue phantom and in vivo in a mouse Met-1 tumor model, using partial parallel imaging (PPI to speed acquisition. An MRgFUS system capable of delivering a controlled 3D acoustic dose during real time MRT with proportional, integral, and derivative (PID feedback control was developed and validated. Real-time MRT was validated in a tofu phantom with fluoroptic temperature measurements, and acoustic heating simulations were in good agreement with MR temperature maps. In an in vivo Met-1 mouse tumor, the real-time PID feedback control is capable of maintaining the desired temperature with high accuracy. We found that real time MR control of hyperthermia is feasible at high field, and k-space based PPI techniques may be implemented for increasing temporal resolution while maintaining temperature accuracy on the order of 1°C.

  13. Synchrotron Radiation Therapy from a Medical Physics point of view

    Science.gov (United States)

    Prezado, Y.; Adam, J. F.; Berkvens, P.; Martinez-Rovira, I.; Fois, G.; Thengumpallil, S.; Edouard, M.; Vautrin, M.; Deman, P.; Bräuer-Krisch, E.; Renier, M.; Elleaume, H.; Estève, F.; Bravin, A.

    2010-07-01

    Synchrotron radiation (SR) therapy is a promising alternative to treat brain tumors, whose management is limited due to the high morbidity of the surrounding healthy tissues. Several approaches are being explored by using SR at the European Synchrotron Radiation Facility (ESRF), where three techniques are under development Synchrotron Stereotactic Radiation Therapy (SSRT), Microbeam Radiation Therapy (MRT) and Minibeam Radiation Therapy (MBRT). The sucess of the preclinical studies on SSRT and MRT has paved the way to clinical trials currently in preparation at the ESRF. With this aim, different dosimetric aspects from both theoretical and experimental points of view have been assessed. In particular, the definition of safe irradiation protocols, the beam energy providing the best balance between tumor treatment and healthy tissue sparing in MRT and MBRT, the special dosimetric considerations for small field dosimetry, etc will be described. In addition, for the clinical trials, the definition of appropiate dosimetry protocols for patients according to the well established European Medical Physics recommendations will be discussed. Finally, the state of the art of the MBRT technical developments at the ESRF will be presented. In 2006 A. Dilmanian and collaborators proposed the use of thicker microbeams (0.36-0.68 mm). This new type of radiotherapy is the most recently implemented technique at the ESRF and it has been called MBRT. The main advantage of MBRT with respect to MRT is that it does not require high dose rates. Therefore it can be more easily applied and extended outside synchrotron sources in the future.

  14. Diagnostic possibilities following implantation of carbon-fibre-reinforced plastic (CFRP) total hip arthroplasty

    International Nuclear Information System (INIS)

    Krueger, T.; Reichel, H.; Birke, A.; Hein, W.; Alter, C.; Spielmann, R.P.

    1998-01-01

    Introduction: There are many problems in the radiological diagnosis of aseptic loosening in total hip arthroplasty. Computed tomography (CT) and magnetic resonance tomography (MRT) are not usable for metallic implants (stainless steel, cobalt alloy, titanium alloy). Material and Methods: From April 1993 to December 1993 15 CFRP non-cemented hip prostheses have been implanted. In a prospective clinical study plane radiographs, CT and MRT have been analysed. Results: Three stems were revised (1 femoral fracture, 1 severe thigh pain, 1 aseptic loosening). CFRP are not visible in plane radiographs. There was a complete (two-third of the cases) or nearly complete (one-third of the cases) small sclerotic interface between the prosthesis and the bone, these were apparent in CT and MRT in stable implant cases and did not have any clinical correlations. Discussion: The small sclerotic interface is quite different in comparison to so called 'Reactive lines'. In one case of aseptic loosening there was an interposition of soft tissue between prothesis and bone in MRT and CT. CFRP inaugurates new diagnostic possibilities in aseptic loosening of hip prosthesis and in tumour surgery too. (orig.) [de

  15. Leaf-level nitrogen use efficiency: definition and importance.

    Science.gov (United States)

    Hirose, Tadaki

    2012-07-01

    Nitrogen use efficiency (NUE) has been widely used to study the relationship between nitrogen uptake and dry mass production in the plant. As a subsystem of plant nitrogen use efficiency (NUE), I have defined leaf-level NUE as the surplus production (gross production minus leaf respiration) per unit amount of nitrogen allocated to the leaf, with factorization into leaf nitrogen productivity (NP) and mean residence time of leaf nitrogen (MRT). These concepts were applied to two herbaceous stands: a perennial Solidago altissima stand and an annual Amaranthus patulus stand. S. altissima had more than three times higher leaf NUE than A. patulus due to nearly three times longer MRT of leaf N. In both species, NUE and NP were higher at the leaf level than at the plant level, because most leaf N is involved directly in the photosynthetic activity and because leaf surplus production is higher than the plant net production. MRT was longer at the plant level. The more than twice as long MRT at the plant level as at the leaf level in S. altissima was due to a large contribution of nitrogen storage belowground in the winter in this species. Thus, comparisons between a perennial and an annual system and between plant- and leaf-level NUE with their components revealed the importance of N allocation, storage, recycling, and turnover of organs for leaf photosynthetic production and plant dry mass growth.

  16. Milk Hygiene in Commercial Dairy Farms in South Eastern Botswana

    African Journals Online (AJOL)

    NVL) on somatic cell counts (SCC), milk ring test (MRT), resazurin test (RST), coliform test (CFT) and Escherichia coli tect (ECT). In general, farms where machine-milking was used recorded the highest SCC, CFT and ECT counts than where ...

  17. 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 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.

  18. Mental Rotational Ability Is Correlated with Spatial but Not Verbal Working Memory Performance and P300 Amplitude in Males

    Science.gov (United States)

    Christie, Gregory J.; Cook, Charles M.; Ward, Brian J.; Tata, Matthew S.; Sutherland, Janice; Sutherland, Robert J.; Saucier, Deborah M.

    2013-01-01

    This study investigated how both sex and individual differences in a mental rotation test (MRT) influence performance on working memory (WM). To identify the neural substrate supporting these differences, brain electrical activity was measured using the event-related potential technique. No significant sex differences were observed in a test of verbal WM, however males were significantly faster than females to respond to probe stimuli in a test of spatial WM. This difference was no longer significant after controlling for differences in MRT score, suggesting that rotational ability mediates performance in the spatial memory task for both sexes. A posterior P300 was observed in both tasks as participants encoded information into memory, however the amplitude of the P300 correlated with RT in the spatial task but not in the verbal task. Individual differences in the MRT also correlated with RT and with the amplitude of the P300, but again only in the spatial task. After splitting the analysis by sex, partial correlations controlling for MRT revealed that for males, individual differences in rotational ability completely mediated the correlation between the P300 and RT in the spatial task. This mediating effect was not observed for the female participants. The results therefore suggest a relatively stronger association in males between innate mental rotational ability, spatial memory performance, and brain electrophysiological processes supporting spatial memory. PMID:23437381

  19. SOLWEIG 1.0--modelling spatial variations of 3D radiant fluxes and mean radiant temperature in complex urban settings.

    Science.gov (United States)

    Lindberg, Fredrik; Holmer, Björn; Thorsson, Sofia

    2008-09-01

    The mean radiant temperature, T(mrt), which sums up all shortwave and longwave radiation fluxes (both direct and reflected) to which the human body is exposed is one of the key meteorological parameters governing human energy balance and the thermal comfort of man. In this paper, a new radiation model (SOLWEIG 1.0), which simulates spatial variations of 3D radiation fluxes and T(mrt) in complex urban settings, is presented. The T(mrt) is derived by modelling shortwave and longwave radiation fluxes in six directions (upward, downward and from the four cardinal points) and angular factors. The model requires a limited number of inputs, such as direct, diffuse and global shortwave radiation, air temperature, relative humidity, urban geometry and geographical information (latitude, longitude and elevation). The model was evaluated using 7 days of integral radiation measurements at two sites with different building geometries--a large square and a small courtyard in Göteborg, Sweden (57 degrees N)--across different seasons and in various weather conditions. The evaluation reveals good agreement between modelled and measured values of T(mrt), with an overall good correspondence of R (2) = 0.94, (p < 0.01, RMSE = 4.8 K). SOLWEIG 1.0 is still under development. Future work will incorporate a vegetation scheme, as well as an improvement of the estimation of fluxes from the four cardinal points.

  20. 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

  1. Gender-Specific Effects of Artificially Induced Gender Beliefs in Mental Rotation

    Science.gov (United States)

    Heil, Martin; Jansen, Petra; Quaiser-Pohl, Claudia; Neuburger, Sarah

    2012-01-01

    Men outperform women in the Mental Rotation Test (MRT) by about one standard deviation. The present study replicated a gender belief account [Moe, A., & Pazzaglia, F. (2006). Following the instructions! Effects of gender beliefs in mental rotation. Learning and Individual Differences, 16, 369-377.] for (part of) this effect. A sample of 300…

  2. Vinnige identifikasiemetodes van giste tydens fungemie

    African Journals Online (AJOL)

    16 Mrt. 1991 ... vinnige sifting om C. albicans van ander gisspesies te onderskei. In gevalie waar dit bekend is dat antifungusmiddels aan pasiente toegedien word, moet in ag geneem word dat vals- negatiewe resultate kan voorkom. Vir die fmale diagnose van die kiembuis-afwesige giste is die gewysigde SDM gebruik.

  3. Radiotracer investigations for tracing catalyst phase in a Fluid Catalytic Cracking Unit (FCCU) in a petroleum refinery

    International Nuclear Information System (INIS)

    Pant, H.J.; Singh, Gursharan; Nair, A.G.C.; Tomar, B.S.

    2006-01-01

    This paper describes characterization, production and application of lanthanum-140 as a radiotracer for evaluation of radial mixing, measurement of mean residence time (MRT) and estimation of degree of axial mixing of catalyst phase in an FCCU in a petroleum refinery

  4. Keorapetse Kgotsitsile (1938–2018)

    African Journals Online (AJOL)

    19 Mrt. 2018 ... Ek het Keorapetse Kgotsitsile die eerste keer ont- moet tydens die Culture & Resistance-konferensie in Gaborone, Botswana in Julie 1982. Ek onthou die kort, maer mannetjie goed. Hy was vir die duur van die konferensie, altyd op 'n draf stappie besig om met bondels papiere onder die arm kruis en dwars.

  5. Effect of rotation bump on removal torque of orthodontic mini-implants.

    Science.gov (United States)

    Gansukh, Odontuya; Jeong, Jong-Wha; Kim, Jong-Wan; Kim, Young-Kyun; Lee, Jong-Ho; Kim, Tae-Woo

    2013-12-01

    This study is designed to evaluate the mechanical stability of orthodontic mini-implants with vertical grooves in rabbits. This study was done from March 2011 to February 2012 in Dental Research Institute of Seoul National University. Thirty-two mini-implants in the control group and 32 in the rotation bump (RB) group were inserted in the tibias of 16 rabbits and were removed after two weeks and four weeks, respectively. The maximum insertion torque (MIT), maximum removal torque (MRT), torque ratio (TR) of MRT to MIT and removal angular momentum (RAM) were all measured at the time of removal. There were no significant differences between the two groups in MIT and MRT at two weeks or four weeks. However, TR and RAM at four weeks in the RB group were significantly higher than in the control group (P<0.05). TR of the RB group was significantly increased at four weeks (P<0.05). In both groups, RAM at four weeks was significantly higher than at two weeks (P<0.05). These results suggest that RB of the mini-implant could provide resistance to the removal rotation, although it did not increase the MRT.

  6. 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.

  7. Efesiërs 1:14 en 1:22, 23 as 'n skriftuurlike maksimum-minimum vir ...

    African Journals Online (AJOL)

    24 Mrt. 2017 ... ontstaan om ekklesiologie te diversifiseer asof daar sprake is van verskillende ekklesiologiese paradigmas (binne Bybelse konteks). In die hedendaagse debat word ook gewag gemaak van missionale ekklesiologie wat gegrond is in die missionale paradigma:1 that the church find its identity in God's ...

  8. TxDOT wildland fire management training.

    Science.gov (United States)

    2014-06-01

    In 2011, the Texas Tech Center for Multidisciplinary Research in Transportation (TechMRT) was contracted by the Texas Department of Transportation (TxDOT) to analyze best practices for the department in responding to wildfires. This project (0-6735) ...

  9. 286 HOMOSISTINURIE: BESKRYWING VAN 'N GEVAL*

    African Journals Online (AJOL)

    13 Mrt. 1971 ... ment verhouding. 'n Hoe verhemelte, pectus excavatum, skoliose, kifose, genu valgum en pes planus kan ook teen- woordig wees. AIgemene osteoporose is radiologies baie kenmerkend met tipiese viswerwels, 'n mate van werwel-. kolIaps en soms patologiese frakture. Kardiovaskulere en hemopoetiese ...

  10. 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.

  11. Restless Mind, Restless Body

    Science.gov (United States)

    Seli, Paul; Carriere, Jonathan S. A.; Thomson, David R.; Cheyne, James Allan; Martens, Kaylena A. Ehgoetz; Smilek, Daniel

    2014-01-01

    In the present work, we investigate the hypothesis that failures of task-related executive control that occur during episodes of mind wandering are associated with an increase in extraneous movements (fidgeting). In 2 studies, we assessed mind wandering using thought probes while participants performed the metronome response task (MRT), which…

  12. Imaging diagnosis of cardial chloroma; Bildgebung kardialer Chlorome

    Energy Technology Data Exchange (ETDEWEB)

    Esser, M.; Doerfel, D.; Mueller, I.; Horger, M.

    2016-06-15

    Cardiac chloroma are a seldom extramedullary manifestation of myeloproliferant and dysplastic diseases. An adequate imaging based on multimodal approaches is of importance for diagnosis. Perfusion CT allows identification of the extent of myocardial chlorome infiltration. The reliability of the method seems to be more efficient than cardiac MRT. For validation histological tests are unavoidable.

  13. On the Foundational Equations of the Classical Theory of ...

    Indian Academy of Sciences (India)

    IAS Admin

    1 Strictly speaking, this notion of an inertial observer is no longer valid, because distant stars and ... the French Systµeme international d'unit¶es) is used throughout this article. Electromagnetic (EM) phenom- ..... and M(r,t), in the sense that, mathematically speak- ing, these functions can have arbitrary values at various.

  14. Media Richness Perspective of Social Media Usage for Learning: Perception of Cocoa Researchers in Ghana

    DEFF Research Database (Denmark)

    Gyamfi, Albert

    2018-01-01

    (MRT). This framework was used to investigate the Ghana Cocoa Board (COCBOD) to investigate which social media platform used by this organization was effective for organizational learning. Data was gathered and analysed using surveys and hierarchical second-order structural equation modeling (SEM...

  15. The RTD measurement of two stage anaerobic digester using radiotracer in WWTP

    International Nuclear Information System (INIS)

    Jin-Seop, Kim; Jong-Bum, Kim; Sung-Hee, Jung

    2006-01-01

    The aims of this study are to assess the existence and location of the stagnant zone by estimating the MRT (mean residence time) on the two stage anaerobic digester, with the results to be used as informative clue for its better operation

  16. Diverse artikelen in Gay Amsterdam News

    NARCIS (Netherlands)

    Hekma, G.

    2002-01-01

    Vernedering, in: Gay Amsterdam News 125 (jan 2002), pp. 20-21; Webseks, zaad, zweetseks, in: Gay Amsterdam News 126 (feb 2002), pp. 30-31; Wurgseks, in: Gay Amsterdam News 127 (mrt 2002), pp. 30-31; Wijnandus Johannes Sengers (1927-2002), in: Gay Amsterdam News 133 (sept 2002), pp. 49.

  17. Rehabilitation of aphasia: application of melodic-rhythmic therapy to Italian language.

    Science.gov (United States)

    Cortese, Maria Daniela; Riganello, Francesco; Arcuri, Francesco; Pignataro, Luigina Maria; Buglione, Iolanda

    2015-01-01

    Aphasia is a complex disorder, frequent after stroke (with an incidence of 38%), with a detailed pathophysiological characterization. Effective approaches are crucial for devising 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, including amongst those with a neurobehavioral approach the Melodic Intonation Therapy (MIT). Van Eeckhout's adaptation of MIT to French language (Melodic-Rhythmic Therapy: MRT) has implemented the training strategy by adding a rhythmic structure reproducing French prosody. The purpose of this study was to adapt MRT rehabilitation procedures to Italian language and to verify its efficacy in a group of six chronic patients (five males) with severe non-fluent aphasia and without specific aphasic treatments during the previous 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 (AAT) 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.

  18. Resilience Training for Healthcare Staff (RTHS) Implementation Evaluation Phase 1

    Science.gov (United States)

    2017-01-05

    05-01-2017 2. REPORT TYPE Technical Report 3. DATES COVERED (From - To) JUN 2016 - JAN 2017 4. TITLE AND SUBTITLE Resilience Training for...DISTRIBUTION/AVAILABILITY STATEMENT Approved for public release: distribution unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT The Master Resilience ...Training (MRT) Medical Program includes a 2-hour Resilience Training for Healthcare Staff (RTHS) aimed to bolster resilience by preventing

  19. 'n ope brief aan Dorian Gray en 'n peiling van die Afrikaanse ...

    African Journals Online (AJOL)

    19 Mrt. 2018 ... “Reviewing Irish books: the good, the bad and the ugly truth.” Daar is 'n aantal redes waarom ek na hierdie artikel verwys. Eerstens vertoon die Ierse en Afrikaanse sisteme 'n aantal ooreenkomste. Beide sisteme is relatief klein en 'n beperkte aantal rolspelers is by resensering betrokke. Dit veroorsaak dat.

  20. 48. Annual meeting of the Deutsche Gesellschaft fuer Neuroradiologie. Joint annual meeting of the DGNR and OeGNR. Abstracts; 48. Jahrestagung der Deutschen Gesellschaft fuer Neuroradiologie. Gemeinsame Jahrestagung der DGNR und OeGNR. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-09-15

    The conference proceedings of the 48. Annual meeting of the Deutsche Gesellschaft fuer Neuroradiologie contain abstracts on the following issues: neuro-oncological imaging, multimodal imaging concepts, subcranial imaging, spinal codes, interventional neuroradiology, innovative techniques like high-field MRT and hybrid imaging methods, inflammable and metabolic central nervous system diseases and epilepsy.

  1. [Stress fracture of the ulna in a table tennis player].

    Science.gov (United States)

    Dufek, P; Ostendorf, U; Thormählen, F

    1999-06-01

    This case report describes a stress fracture of the ulna in a 26-year-old professional table-tennis player. X-ray films remained negative so that the diagnostic is based on MRT. This stress fracture is caused by changing the intensity of training and changing the table-tennis-racket.

  2. UNISWA Research Journal of Agriculture, Science and Technology

    African Journals Online (AJOL)

    NVL) on somatic cell counts (SCC), milk ring test (MRT), resazurin test (RST), coliform test (CFT) and Escherichia coli tect (ECT). In general, farms where machine-milking was used recorded the highest SCC, CFT and ECT counts than where ...

  3. 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.

  4. 01 Bosman

    African Journals Online (AJOL)

    Tom

    11 Mrt. 2004 ... het die daaglikse brood geword van studente, dosente, biblioteka- resse, skrywers en van sy bitterste aanvallers. (…) [Dikwels] word daar (…) onderskei tussen 'n hoë en 'n lae wetenskap. (…) By ons, soos elders, is so 'n onderskeiding eerder 'n bewys van snobisme as van vermoë, want oor die algemeen ...

  5. 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.

  6. 77 FR 55492 - Mortgagee Review Board: Administrative Actions

    Science.gov (United States)

    2012-09-10

    ... of Pennsylvania; failed to ensure that only principal owners or corporate officers submit the annual... statements to HUD that were not in conformity with Generally Accepted Accounting Principles due to the... Mortgage, Inc., Jonesboro, AR [Docket No. 12-1642- MRT]. 2. HCL Finance Inc., San Jose, CA . 3. Ikon...

  7. Variable temperature sensitivity of soil organic carbon in North American forests

    Science.gov (United States)

    Cinzia Fissore; Christian P. Giardina; Christopher W. Swanston; Gary M. King; Randall K. Kolka

    2009-01-01

    We investigated mean residence time (MRT) for soil organic carbon (SOC) sampled from paired hardwood and pine forests located along a 22 °C mean annual temperature (MAT) gradient in North America. We used acid hydrolysis fractionation, radiocarbon analyses, long-term laboratory incubations (525-d), and a three-pool model to describe the size and kinetics of...

  8. Bone Conduction Systems for Full-Face Respirators: Speech Intelligibility Analysis

    Science.gov (United States)

    2014-04-01

    vocabularies representative of operational military communications (ANSI/ASA S3.2-2009). The MRT consists of 300 monosyllabic consonant- vowel -consonant (CVC...Biological, Radiological, Nuclear, and Explosive CVC consonant- vowel -consonant dBA decibels (A-weighted) EAR Environment for Auditory Research FoS

  9. R. E. van der Ross (1921–2017)

    African Journals Online (AJOL)

    19 Mrt. 2018 ... Sedert sy jeug het Richard Ernest van der Ross. (1921–2017) 'n belangrike rol in die breë Kaapse ge- meenskap gespeel. Hy het hom onderskei as 'n anti- apartheidsaktivis, 'n opvoedkundige, 'n geskied- skrywer en openbare intellektueel, 'n vakbondmens,. 'n gemeenskapsbouer, 'n maatskappydirekteur ...

  10. Individual Differences in the Mental Rotation Skills of Turkish Prospective Teachers

    Science.gov (United States)

    Turgut, Melih

    2015-01-01

    This study investigated the effects of gender, academic performance and preschool education on mental rotation skills among Turkish prospective teachers. A total of 525 undergraduate students (364 female) from a government university located in western Turkey completed the Mental Rotation Test (MRT). A three-way [2 (gender) × 5 (academic…

  11. Importance of 3-D radiant flux densities for outdoor human thermal comfort on clear-sky summer days in Freiburg, Southwest Germany

    Directory of Open Access Journals (Sweden)

    Hyunjung Lee

    2014-09-01

    Full Text Available This study concerns the role of short- and long-wave radiant flux densities from different directions in complex urban settings for human thermal comfort on clear-sky summer days. The aims of the investigation are to quantify the importance of the sky view factor as an urban design-dependent variable for the 3-D radiant flux densities absorbed by the standardized human-biometeorological reference person and to analyze the varying impact of the absorbed 3-D short- and long-wave radiant flux densities on the mean radiant temperature (Tmrt$T_{\\text{mrt}}$, near-surface air temperature (Ta$T_{\\text{a}}$ and physiologically equivalent temperature (PET.The results obtained by measuring campaigns and numerical simulations point to the different importance of the absorbed 3-D radiant flux densities for human thermal comfort characterized by Ta$T_{\\text{a}}$, Tmrt$T_{\\text{mrt}}$ and PET. The magnitude of Tmrt$T_{\\text{mrt}}$ is mainly determined by the total of the absorbed 3-D long-wave radiant flux densities. However, the fluctuations of Tmrt$T_{\\text{mrt}}$ are mainly governed by the total of the absorbed 3-D short-wave radiant flux densities. Their variance can be well explained by the variance of the sky view factor related to the southern part of the upper half space. Taking account of the different impact of the 3-D radiant flux densities, Tmrt$T_{\\text{mrt}}$ can be quite well estimated by a multiple regression using the total of the absorbed 3-D short-wave radiant flux densities and the absorbed long-wave radiant flux density from the lower half space as independent variables. PET can be well estimated by a multiple regression showing Tmrt$T_{\\text{mrt}}$ and Ta$T_{\\text{a}}$ as independent variables. On a hot summer day, the increase of the albedo of vertical building walls within a simple E-W oriented street canyon leads to a decrease of the surface temperature of the S-facing wall, but to an increase of Tmrt$T_{\\text{mrt}}$ and PET

  12. 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

  13. Role of nuclear medicine and magnetic resonance imaging in cardiac diagnostics; Rolle der nuklearmedizinischen Verfahren und der Magnetresonanztomographie in der kardialen Diagnostik

    Energy Technology Data Exchange (ETDEWEB)

    Buelow, H.P.; Bengel, F.M. [Nuklearmedizinische Klinik und Poliklinik der Technischen Univ. Muenchen (Germany)

    2003-12-01

    important future role. (orig.) [German] Nuklearmedizinische Untersuchungsmethoden finden ebenso wie die Magnetresonanztomographie (MRT) in der kardialen Diagnostik eine breite Anwendung. Zur Beurteilung der regionalen und globalen Wandbewegung sowie der Bestimmung von Ejektionsfraktion und Herzvolumina sind beide Techniken ausreichend evaluiert und aequivalent einsetzbar, wenngleich die MRT hier mittlerweile als Goldstandard angesehen wird. Hinsichtlich Untersuchungen der myokardialen Perfusion liegen fuer die nuklearmedizinischen Verfahren umfangreiche Daten vor, die neben einer hohen diagnostischen Genauigkeit zur Erkennung der koronaren Herzerkrankung eine zusaetzliche prognostische Aussage belegen und eine unabhaengige Risikostratifizierung der Patienten erlauben. Die kardiale MRT bietet, dank des raschen technischen Fortschritts, ebenfalls die Moeglichkeit zur Beurteilung der myokardialen Perfusion. Die bisherigen Studien hierzu erscheinen vielversprechend, allerdings ist die Datenlage im Gegensatz zur Myokardszintigraphie noch wenig umfangreich. In der Vitalitaetsdiagnostik bei ischaemisch bedingter Herzinsuffizienz gilt gegenwaertig die Positronen-Emissions-Tomographie mit FDG als Goldstandard. Die Single-Photonen-Emissionscomputertomographie (SPECT) mit TI-201 oder Tc-99m-markierten Tracern, wie auch die MRT als niedrig dosierte Dobutamin-Stress-Untersuchung oder als kontrastmittelverstaerkte MRT weisen aber aehnlich gute Ergebnisse auf. Nuklearmedizinische Verfahren und MRT liefern in einigen diagnostischen Teilbereichen Ergebnisse, die mit der jeweils anderen Methode nicht zu erzielen sind. Beispiele hierfuer sind die Evaluierung der sympathischen Innervation, der Endothelfunktion, der Zellapoptose und des Gentransfers auf nuklearmedizinischer Seite sowie die Beurteilung der dreidimensionalen myokardialen Kontraktion, die nicht-invasive Koronarangiographie, die Gefaesswanddarstellung und die Echtzeitbildgebung mit der MRT. Bildfusionen aus nuklearmedizinischen

  14. 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.

  15. COPD patients' oxygen uptake and heart rate on-kinetics at cycle-ergometer: correlation with their predictors of severity.

    Science.gov (United States)

    Pessoa, Bruna V; Beltrame, Thomas; Di Lorenzo, Valéria A Pires; Catai, Aparecida M; Borghi-Silva, Audrey; Jamami, Mauricio

    2013-01-01

    To assess whether there is a correlation between oxygen uptake (VO2) and heart rate (HR) on-kinetics in the constant-load cycle-ergometer test (CLT) and the BODE index and its isolated variables in patients with chronic obstructive pulmonary disease (COPD). Fourteen male patients between 55 and 78 years of age with moderate to severe COPD were evaluated. Each patient underwent spirometry, the six-minute walk test (6MWT), the cycle-ergometer incremental test (IT) and CLT on alternate days. The exhaled gases were collected, and the VO2 and HR on-kinetics were analyzed. The BODE index was calculated. It was noted that the VO2 tau (τ) and mean response time (MRT) were significantly higher than HR τ and MRT. Moderate and strong correlations between τ and MRT of the VO2 and HR and the BODE index was noted (r=0.75 and r=0.78; r=0.62 and r=0.63, respectively), and there were correlations between the VO2 τ and MRT and the forced expiratory volume in one second (FEV1) (r=-0.60; r=-0.53) and the distance traveled at 6MWT (DT-6MWT) (r=-0.61; r=-0.44) and DT-6MWT % predicted (r=-0.62; r=-0.46). The HR τ and MRT were correlated with DT-6MWT (r=-0.59; r=-0.58) and DT-6MWT % predicted (r=-0.62; r=-0.62). The slowing of cycle-ergometer VO2, and especially of HR on-kinetics, may be key markers of disease severity. Furthermore, airflow obstruction and reduced exercise capacity are associated with the slowing of patients' VO2 and HR on-kinetics.

  16. 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.

  17. 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.

  18. Comparison of two methods for measuring γ-H2AX nuclear fluorescence as a marker of DNA damage in cultured human cells: applications for microbeam radiation therapy

    Science.gov (United States)

    Anderson, D.; Andrais, B.; Mirzayans, R.; Siegbahn, E. A.; Fallone, B. G.; Warkentin, B.

    2013-06-01

    Microbeam radiation therapy (MRT) delivers single fractions of very high doses of synchrotron x-rays using arrays of microbeams. In animal experiments, MRT has achieved higher tumour control and less normal tissue toxicity compared to single-fraction broad beam irradiations of much lower dose. The mechanism behind the normal tissue sparing of MRT has yet to be fully explained. An accurate method for evaluating DNA damage, such as the γ-H2AX immunofluorescence assay, will be important for understanding the role of cellular communication in the radiobiological response of normal and cancerous cell types to MRT. We compare two methods of quantifying γ-H2AX nuclear fluorescence for uniformly irradiated cell cultures: manual counting of γ-H2AX foci by eye, and an automated, MATLAB-based fluorescence intensity measurement. We also demonstrate the automated analysis of cell cultures irradiated with an array of microbeams. In addition to offering a relatively high dynamic range of γ-H2AX signal versus irradiation dose ( > 10 Gy), our automated method provides speed, robustness, and objectivity when examining a series of images. Our in-house analysis facilitates the automated extraction of the spatial distribution of the γ-H2AX intensity with respect to the microbeam array — for example, the intensities in the peak (high dose area) and valley (area between two microbeams) regions. The automated analysis is particularly beneficial when processing a large number of samples, as is needed to systematically study the relationship between the numerous dosimetric and geometric parameters involved with MRT (e.g., microbeam width, microbeam spacing, microbeam array dimensions, peak dose, valley dose, and geometric arrangement of multiple arrays) and the resulting DNA damage.

  19. 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.

  20. Follow-up radiographs of the cervical spine after anterior fusion with titanium intervertebral disc; Roentgen-Verlaufsuntersuchung der Halswirbelsaeule nach anteriorer Fusion mit Titaninterponaten

    Energy Technology Data Exchange (ETDEWEB)

    Biederer, J.; Hutzelmann, A.; Heller, M. [Kiel Univ. (Germany). Klinik fuer Diagnostische Radiologie; Rama, B. [Paracelsus Klinik, Osnabrueck (Germany). Klinik fuer Neurochirurgie

    1999-08-01

    Purpose: We examined the postoperative changes of the cervical spine after treatment of cervical nerve root compression with anterior cervical discectomy and fusion with a new titanium intervertebral disc. Patients and Methods: 37 patients were examined prior to, as well as 4 days, 6 weeks, and 7 months after surgery. Lateral view X-rays and functional imaging were used to evaluate posture and mobility of the cervical spine, the position of the implants, and the reactions of adjacent bone structures. Results: Implantation of the titanium disc led to post-operative distraction of the intervertebral space and slight lordosis. Within the first 6 months a slight loss of distraction and re-kyphosis due to impression of the implants into the vertebral end-plates were found in all patients. We noted partial infractions into the vertebral end-plates in 10/42 segments and slight mobility of the implants in 14/42 segments. Both groups of patients showed reactive spondylosis and local symptoms due to loosening of the implants. The pain subsided after onset of bone bridging and stable fixation of the loosened discs. Conclusions: The titanium intervertebral disc provides initial distraction of the fusioned segments with partial recurrence of kyphosis during the subsequent course. Loosening of the implants with local symptoms can be evaluated with follow-up X-rays and functional imaging. (orig.) [German] Ziel: An Patienten mit zervikalen Kompressionssyndromen wurden Stellung und Funktion der Halswirbelsaeule nach Diskektomie und Fusion mit einem neuartigen Titaninterponat untersucht. Patienten und Methoden: Bei 37 Patienten (42 Segmente) wurden praeoperativ sowie 4 Tage, 6 Wochen und 7 Monate postoperativ mit seitlichen Uebersichts- und Funktionsaufnahmen Stellung und Mobilitaet der HWS beurteilt. Erfasst wurden Lageveraenderungen des Titaninterponates und die Reaktion der angrenzenden Wirbelkoerperabschlussplatten. Ergebnisse: Das Titaninterponat bewirkte postoperativ eine

  1. 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.)

  2. Molecular breast imaging. An update; Molekulare Brustbildgebung. Ein Update

    Energy Technology Data Exchange (ETDEWEB)

    Pinker, K.; Helbich, T.H.; Magometschnigg, H.; Baltzer, P. [Medizinische Universitaet Wien, Abteilung fuer Molekulare Bildgebung, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Wien (Austria); Fueger, B. [Medizinische Universitaet Wien, Abteilung fuer Molekulare Bildgebung, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Wien (Austria); Medizinische Universitaet Wien, Abteilung fuer Nuklearmedizin, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Wien (Austria)

    2014-03-15

    The aim of molecular imaging is to visualize and quantify biological, physiological and pathological processes at cellular and molecular levels. Molecular imaging using various techniques has recently become established in breast imaging. Currently molecular imaging techniques comprise multiparametric magnetic resonance imaging (MRI) using dynamic contrast-enhanced MRI (DCE-MRI), diffusion-weighted imaging (DWI), proton MR spectroscopy ({sup 1}H-MRSI), nuclear imaging by breast-specific gamma imaging (BSGI), positron emission tomography (PET) and positron emission mammography (PEM) and combinations of techniques (e.g. PET-CT and multiparametric PET-MRI). Recently, novel techniques for molecular imaging of breast tumors, such as sodium imaging ({sup 23}Na-MRI), phosphorus spectroscopy ({sup 31}P-MRSI) and hyperpolarized MRI as well as specific radiotracers have been developed and are currently under investigation. It can be expected that molecular imaging of breast tumors will enable a simultaneous assessment of the multiple metabolic and molecular processes involved in cancer development and thus an improved detection, characterization, staging and monitoring of response to treatment will become possible. (orig.) [German] Die molekulare Bildgebung zielt auf die Darstellung, Beschreibung und Quantifizierung biologischer, physiologischer und pathologischer Prozesse auf zellulaerer und molekularer Ebene ab. In den letzten Jahren hat sich die molekulare Bildgebung mit ihren verschiedenen Modalitaeten in der Brustdiagnostik etabliert. Die molekularen Brustbildgebung umfasst derzeit die multiparametrische(MP)-MRT mit funktioneller und morphologischer kontrastmittelverstaerkter MRT (KM-MRT), molekularer diffusionsgewichteter Bildgebung (''diffusion-weighted imaging'', DWI) und metabolischer Protonenspektroskopie ({sup 1}H-MRSI) sowie nuklearmedizinische Verfahren (brustspezifische Gammakamerabildgebung [BSGI], Positronenemissionstomographie [PET], PET

  3. Inflammation and tumors of the temporal bone; Entzuendungen und Tumoren des Schlaefenbeins

    Energy Technology Data Exchange (ETDEWEB)

    Burian, M. [Universitaetsklinik fuer Hals-, Nasen- und Ohrenkrankheiten, Allgemeines Krankenhaus, Wien (Austria)

    1997-12-01

    The term `inflammation of the middle ear` covers a couple of deseases which range from the acute otitis media to the middle ear cholesteatoma. However, a clear characterization of a certain pathology is essential for any further treatment. Therefore this article presents a short overview about the different types of infections and their clinical manifestation. The tumors of the temporal bone show a great variety in their incidence. Even if tumors like the acoustic neurinoma or the paraganglioma are compareable common, the chondroblastoma of the temporal bone is absolutely rare. In spite of these differences the individual temporal bone neoplasias are shortly mentioned herein. (orig.) [Deutsch] Der Begriff Mittelohrentzuendung umfasst ein weites Spektrum von Krankheiten welches von der akuten Mittelohrentzuendung bis hin zum Cholesteatom reicht. Es soll in diesem Artikel eine kurze Uebersicht ueber die verschiedenen Entzuendungen gegeben werden, wobei vor allem auf eine klare Begriffsdefinition der einzelnen Entzuendungsformen und deren klinisches Erscheinungsbild geachtet wurde. Bei den Tumoren des Schlaefenbeins ist ein grosser Unterschied in der Inzidenz der einzelnen Tumoren gegeben. Waehrend Neubildungen wie das Akustikusneurinom oder das Paragangliom vergleichsweise haeufig im klinischen Alltag zu sehen sind, stellen Veraenderungen wie das Chondroblastom eine Raritaet dar. Trotz dieses Unterschieds im Vorkommen der verschiedenen Tumoren, wurde versucht, einen kurzen Gesamtueberblick ueber die Tumore des Mittel- und Innenohres zu geben. (orig.)

  4. Identification and evaluation of operative actions in a process plant. Part 1; Darstellung und Bewertung von Bedienhandlungen an einer verfahrenstechnischen Anlage. Teil 1

    Energy Technology Data Exchange (ETDEWEB)

    Peukert, D. [TU Berlin (Germany). Inst. fuer Prozess- und Anlagentechnik; Steinbach, J. [TU Berlin (Germany). Fachgebiet fuer Anlagen- und Sicherheitstechnik; Matthey, R.; Krug, S. [PCK Raffinerie GmbH, Schwedt (Germany)

    2003-04-01

    Concepts for identifying and evaluating operative actions were applied and compared in a dissertation of the Institute of Process and Plant Engineering of TU Berlin University. A plant of PCK Raffinerie GmbH at Schwedt, Oder was used for the investigations. 'Operative actions' in this context were defined as any interference of human operators with the technical system. The findings were to be used by plant operators and licensing authorities for the double purpose of detecting safety gaps and of ensuring plant safety in normal operation and in case of disturbances, taking into account the human factor. [German] Im Rahmen einer Diplomarbeit am Institut fuer Prozess- und Anlagentechnik der Technischen Universitaet Berlin wurden anhand einer verfahrenstechnischen Anlage zur Veredelung von Erdoelprodukten der PCK Raffinerie GmbH in Schwedt/Oder verschiedene Konzepte zur Darstellung und Bewertung von Bedienhandlungen angewandt und verglichen, wobei als Bedienhandlung in diesem Zusammenhang jeder die Prozessfuehrung betreffende Eingriff des Menschen in das technische System angesehen wird. Dabei sollte durch eine angemessene Darstellung der Bedienhandlungen eine verbesserte Uebersicht sowohl fuer den Anlagenbetreiber als auch fuer die ueberwachende Behoerde geschaffen werden, so dass moegliche Sicherheitsluecken erkannt, aber auch die Sicherheit der Anlage im normalen sowie gestoerten Betrieb unter Beruecksichtigung des Bedieners nachgewiesen werden koennen. (orig.)

  5. Mechatronics. Fundamentals and applications of technical systems. 2. upd. and enl. ed.; Mechatronik. Grundlagen und Anwendungen technischer Systeme

    Energy Technology Data Exchange (ETDEWEB)

    Czichos, Horst

    2008-07-01

    The book directs to college students and engineers in practice. Presentation of practical applications like e.g. CD-players, industry robots, automobile sensorics. THe actual edition was completed by medicinal engineering. The main topics are: fundamentals on data processing; technical communication; test engineering; quality management; materials engineering; mechanical systems; production of mechanical systems; fundamentals on electrical engineering; electric machines and devices; control systems; remote systems in automation engineering; mechatronic systems and their installation, commissioning and maintenance. (GL) [German] Dieses Fachbuch beschreibt mit aussagekraeftigen Abbildungen kurz und praegnant die Grundlagen und Anwendungen der Mechatronik: von der Makro- und Mikrotechnik bis hin zur Nanotechnik. Erstmalig wird durchgaengig eine ganzheitlich-systemtechnische Behandlung mechatronischer Systeme vorgenommen. Ein Schwerpunkt liegt in der Darstellung von Praxisanwendungen wie z. B. CD-Player, Industrieroboter, Automobilsensorik. Die aktuelle Auflage wurde um die Entwicklungsmethodik fuer mechatronische Systeme und ein neues Kapitel Medizintechnik ergaenzt. Ausserdem wurden die Grundlagen vertieft (z. B. Magneto- und Optoelektronik in der Mechatronik) sowie die Anzahl der Anwendungsbeispiele erweitert. Aus dem Inhalt Teil A Grundlagen: Uebersicht - Einfuehrung in die systemtechnische Methodik - Modellbildung mechatronischer Systeme - Regelung und Steuerung - Sensorik - Aktorik Teil B Anwendungen: Maschinenbau - Positionierungstechnik und Robotik - Produktionstechnik - Feinwerktechnik - Audio-Video-Technik - Computertechnik - Fahrzeugtechnik - Medizintechnik - Bauliche Anlagen. (orig.)

  6. Modelling of fluidized bed granulation using population balances; Beitrag zur Modellbildung von eigenschaftsverteilten dispersen Systemen am Beispiel der Wirbelschicht-Spruehagglomeration

    Energy Technology Data Exchange (ETDEWEB)

    Peglow, M.

    2005-07-01

    The report is in two parts. The first part presents general formulations, analytical solutions and numeric methods for describing aggregation processes. New models are presented for calculating problems of population dynamics which may improve or replace existing approaches. The second part presents a model for calculating heat and mass transfer processes and aggregation mechanisms in fluidized-bed spray agglomeration. The new approaches presented in the first part are used and validated. For the first time ever, the mass and energy balances between the solid and gaseous phase are coupled completely in consideration of the aggregation processes. (orig.) [German] Die vorliegende Arbeit gliedert sich in zwei Teile. Der erste Teil beinhaltet eine Uebersicht zu allgemeinen Formulierungen, analytischen Loesungen und numerischen Methoden zur Beschreibung von Aggregationsprozessen. Weiterhin werden neue Modelle zur Berechnung von populationsdynamischen Problemen vorgeschlagen, welche bestehende Ansaetze verbessern oder ersetzen koennen. Im zweiten Teil der Arbeit wird ein Modell zur Berechnung der Waerme- und Stofftransportvorgaenge sowie Aggregationsmechanismen bei der Wirbelschichtspruehagglomeration vorgestellt. Hierbei werden die neuen Loesungsansaetze aus dem ersten Teil direkt umgesetzt und anhand experimenteller Untersuchungen validiert. Es erfolgt erstmalig eine vollstaendige Kopplung der Massen- und Energiebilanzen zwischen Feststoff- und Gasphase unter Beruecksichtigung der Aggregationsprozesse. (orig.)

  7. German energy market 2016; Deutscher Energiemarkt 2016

    Energy Technology Data Exchange (ETDEWEB)

    Schiffer, Hans-Wilhelm [World Energy Council, London (United Kingdom). World Energy Resources; Weltenergierat, Berlin (Germany). Arbeitsgruppe Energie fuer Deutschland

    2017-03-15

    The basic orientation of the German energy supply to the increased use of renewable energies, while increasing energy efficiency, is prediscribed by the German government's energy concept and determines the market development. A current overview of the German energy market is given, which provides also this year a concentrated Compilation of the key data of the energy industry. As in the years before, the article not only summarizes general facts about the energy mix, but also goes into detail on the development of the individual energy sources, petroleum, natural gas, brown coal and hard coal, electricity as well as renewable energies. Furthermore, the price trends of international markets and in the domestic market are explained. A current overview of the development of greenhouse gas emissions concludes the contribution. [German] Die im Energiekonzept der Bundesregierung vorgegebene Grundausrichtung der deutschen Energieversorgung hin zur verstaerkten Nutzung erneuerbarer Energien bei gleichzeitiger Steigerung der Energieeffizienz bestimmt die Marktentwicklung. Vorliegend wird ein aktueller Ueberblick ueber den deutschen Energiemarkt gegeben, der auch in diesem Jahr eine konzentrierte Zusammenstellung der zentralen Eckdaten der Energiewirtschaft leistet. Wie in den Jahren zuvor fasst der Artikel nicht nur allgemeine Fakten zum Energiemix zusammen, sondern geht auch ausfuehrlich auf die Entwicklung der einzelnen Energietraeger Erdoel, Erdgas, Braun- und Steinkohle, Elektrizitaet sowie regenerative Energien ein. Ferner werden die Preistendenzen auf den internationalen Maerkten und im Inland erlaeutert. Eine aktuelle Uebersicht ueber die Entwicklung der Treibhausgas-Emissionen schliesst den Beitrag ab.

  8. The environmental agency of North-Rhine-Westphalia. Annual report 1995; Landesumweltamt Nordrhein-Westfalen. Jahresbericht `95

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    The annual reports of the environmental agency of North-Rhine-Westphalia periodically inform on topics, developments and events. In its choice of technical topics, the agency was guided by the following aspects: topicality, significance for workers in this technical field and, especially, general technical interest. Consequently, this volume is not a report of activities but provides insight into the work of the agency, stimulates cooperation and helps to establish and intensify connections. The short papers fall into the subject categories water, soil, atmosphere, technical systems and information systems, permitting rapid survey. The subjects of the longer contributions were chosen right across the entire range of activities of the environmental agency. Aspects relating to several media of course had an influence on this choice. (orig./SR) [Deutsch] Die Jahresberichte des Landesumweltamtes NRW geben periodisch eine Uebersicht ueber Themen, Entwicklungen und Ereignisse. Bei der Auswahl der Fachthemen laesst sich das Landesumweltamt von der Aktualitaet, der Bedeutung fuer die Fachwelt und auch von dem allgemeinen Fachinteresse leiten. Dieser Jahresbericht `95 ist somit kein Rechenschaftsbericht, sondern gibt Einblick in die Arbeit, soll zur Zusammenarbeit anregen, vielfaeltige fachliche Verbindungen knuepfen und festigen. Zur besseren Uebersichtlichkeit sind die Kurzbeitraege gegliedert in: Wasser, Boden, Luft, Technik und Informationssysteme. Die Hauptbeitraege setzen Schwerpunkte `quer durch das Landesumweltamt`, bei denen natuerlich medienuebergreifende Gesichtspunkte eine Rolle gespielt haben. (orig./SR)

  9. Contrast media in renal insufficiency - risk and prevention; Auswirkungen einer intravasalen Roentgenkontrastmittelgabe auf die Nierenfunktion - Risiken und Praevention

    Energy Technology Data Exchange (ETDEWEB)

    Erley, C.M.; Bader, B.D. [Tuebingen Univ. (Germany). Abt. fuer Innere Medizin III

    2000-10-01

    The use of iodinated contrast media (CM) continues to be a common cause of hospital-acquired acute renal failure (ARF) and its development increases the in-hospital mortality significantly. Alterations in renal hemodynamics and direct tubular toxicity by contrast media are the primary factors believed to be responsible for contrast media-associated nephrotoxicity. We review recent insights into the pathogenesis of this complication and summarize prophylacttic strategies focussing on hydration, vasoactive pharmacological agents, alternative contrast media and 'prophylactic hemodialysis'. (orig.) [German] Das durch Roentgenkontrastmittelgabe initiierte Nierenversagen, die sogenannte Kontrastmittelnephropathie (KMN), stellt - insbesondere bei Patienten mit eingeschraekuter Nierenfunktion - nach wie vor ein erhebliches medizinisches Problem dar, dessen Auftreten mit einer deutlich erhoehten Krankenhausmortalitaet verbunden ist. Die Genese der KMN ist nach wie vor nicht eindeutig geklaert. Neben haemodynamischen Veraenderungen durch die Kontrastmittel spielen tubulotoxische Schaeden eine Rolle. Die vorliegende Uebersicht beschreibt die zur Zeit bekannten pathophysiologischen Vorgaenge bei der KMN und die moeglichen Praeventivmassnahmen mit besonderem Augenmerk auf die klinisch relevanten Themen der Hydratation, der prophylaktischen Gabe vasoaktiver Substanzen, den Einsatz alternativer Kontrastmittel und die Entfernung von Roentgenkontrastmitteln (KM) mittels Haemodialyse. (orig.)

  10. White matter alterations in neurodegenerative and vascular dementia; Marklagerveraenderungen bei neurodegenerativen und vaskulaeren Demenzerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Supprian, T. [Arbeitsgruppe Gerontopsychiatrie, Universitaets-Nervenklinik Homburg (Germany); Arbeitsgruppe Gerontopsychiatrie, Universitaets-Nervenklinik, Psychiatrie und Psychotherapie, 66421, Homburg (Germany); Kessler, H.; Falkai, P. [Arbeitsgruppe Gerontopsychiatrie, Universitaets-Nervenklinik Homburg (Germany); Retz, W.; Roesler, M. [Arbeitsgruppe Gerontopsychiatrie, Universitaets-Nervenklinik Homburg (Germany); Institut fuer gerichtliche Psychologie und Psychiatrie, Universitaet des Saarlandes, Homburg (Germany); Grunwald, I.; Reith, W. [Abteilung fuer Neuroradiologie, Universitaetskliniken des Saarlandes, Homburg (Germany)

    2003-07-01

    Due to a significant overlap of the two syndromes, differentiation of degenerative dementia of the Alzheimer-type from vascular dementia may be difficult even when imaging studies are available. White matter changes occur in many patients suffering from Alzheimer's disease. Little is known about the impact of white matter changes on the course and clinical presentation of Alzheimer's disease. High sensitivity of MRI in the detection of white matter alterations may account for over-diagnosing vascular dementia. The clinical significance of white matter alterations in dementia is still a matter of debate. The article reviews current concepts about the role of white matter alterations in dementia. (orig.) [German] Die Zuordnung einer Demenzerkrankung zu einem neurodegenerativen Pathomechanismus, wie der Demenz vom Alzheimer-Typ (DAT) oder einem vaskulaeren Pathomechanismus, kann trotz der Verfuegbarkeit bildgebender Verfahren Probleme bereiten. Ueberlappungen neurodegenerativer und vaskulaerer Mechanismen sind haeufig. Mikroangiopathische Veraenderungen des Marklagers finden sich bei einem hohen Anteil von Patienten mit der klinischen Verlaufsform einer Demenz vom Alzheimer-Typ. Es ist unklar, ob es sich um eine Koinzidenz zweier Pathomechanismen handelt oder ob eine wechselseitige Beeinflussung stattfindet. Die hohe Sensitivitaet der Magnetresonanztomographie bei der Erfassung mikroangiopathischer Veraenderungen des Marklagers koennte dazu fuehren, dass zu vaskulaere Demenzerkrankungen haeufig diagnostiziert werden. Der Einfluss mikroangiopathischer Veraenderungen des Marklagers auf den Demenzverlauf wird kontrovers diskutiert. Die vorgelegte Arbeit gibt eine Uebersicht ueber die aktuellen Konzepte zum Stellenwert von Marklagerveraenderungen bei Demenzerkrankungen. (orig.)

  11. Successful treatment of a rare case of ameloblastic fibrosarcoma with radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Oertel, Michael; Reinartz, Gabriele; Scobioala, Sergiu; Eich, Hans Theodor [University Hospital of Muenster, Department of Radiation Oncology, Muenster (Germany)

    2017-08-15

    Sarcomas are rare diseases of the head and neck region, representing around 1% of all malignancies. Amongst them, ameloblastic fibrosarcoma (AFS) is of even greater rarity, with less than 100 cases reported in the literature. Consequently, no standard treatment or guidelines have been made available. Surgery is often performed as primary therapy, but may be limited due to anatomical or functional reasons. We present a case of AFS successfully treated by postoperative radiation therapy. A detailed case study is provided, followed by a review of the English-language literature focusing on the role of radiation therapy. (orig.) [German] Sarkome sind in der Kopf-Hals-Region seltene Tumore mit einem Anteil von ca. 1 % an allen malignen Erkrankungen. Das ameloblastische Fibrosarkom (AFS) ist wiederum von noch groesserer Seltenheit, mit weniger als 100 berichteten Faellen in der Literatur. Entsprechend konnte bis jetzt kein Standardvorgehen etabliert werden. Chirurgische Interventionen werden haeufig als Primaertherapie durchgefuehrt, sind jedoch aus anatomischen bzw. funktionalen Gruenden limitiert. Wir stellen den Fall eines AFS vor, das erfolgreich mit einer postoperativen Radiotherapie behandelt wurde. Eine detaillierte Fallstudie wird ergaenzt durch eine Uebersicht der englischsprachigen Literatur zu diesem Thema unter besonderer Beruecksichtigung der Rolle der Strahlentherapie. (orig.)

  12. Comparison of software for thermodynamic process calculation. Results of the VGB research project No. 177

    Energy Technology Data Exchange (ETDEWEB)

    Giglmayr, I.; Pogoreutz, M. [Technische Univ., Graz (Austria). Inst. fuer Waermetechnik; Nixdorf, M. [Technische Univ. Muenchen (Germany). Inst. of Thermal Power Systems

    2001-07-01

    The VGB Research Project No. 177 'Comparison of Software for Thermodynamic Process Calculation' gives an overview of 16 programmes commercially available and aims at presenting an objective comparison of them. This comparison is essentially based on the method of utility value analysis. As, however, the requirements to be met by these programmes differ considerably, no generally valid ranking/recommendation can be given. Thus, the programme Quick Select is a tool for the potential user which can be applied to establish a ranking designed to meet his own specific requirements. (orig.) [German] Das VGB-Forschungsvorhaben Nr. 177 'Vergleich von Software zur thermodynamischen Prozessrechnung' gibt eine Uebersicht ueber 16 kommerziell angebotene Programme und gestattet ihre Beurteilung. Der Vergleich der Leistungsfaehigkeit stuetzt sich im Wesentlichen auf die Methode der Nutzwertanalyse, wobei aufgrund der stark divergierenden Anforderungen an die Programme keine allgemein gueltige Reihung/Empfehlung gegeben werden kann. Das im Rahmen der Projektbearbeitung entwickelte Programm Quick Select ermoeglicht jedoch dem potentiellen Anwender, ein Ranking fuer seine eigenen Ansprueche zu erstellen. (orig.)

  13. ATV manual: Industrial effluents of the chemical industry, food processing industry, consumer goods industries and public services. 4. ed.; ATV-Handbuch: Industrieabwasser - Dienstleistungs- und Veredelungsindustrie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The book describes liquid effluents of the following industries: Animal and plant production; flesh meal production; sausage casings processing; leather, glue and gelatine production; fish meal production; paper and cellulose production; textile industry; motor car repair shops; railway industry; carwash facilities; military services; tank cleaning; laundries and cleaners'; waste management systems; hospitals. Each chapter contains information on the industry concerned, its capacity and products, including all process stages, technologies, and flowcharts. Effluent-relevant process stages are analyzed, and their environmental relevance is assessed. In each case, the available options for waste treatment are pointed out. Practical example, technical data and cost figures supplement the text. [German] Das vorliegende ATV-Handbuch behandelt die wichtigsten Industriebranchen der Dienstleistungs- und Veredelungsindustrie: Betriebe der Tier- und Pflanzenproduktion - Fleischmehlindustrie - Naturdarmbearbeitungsbetriebe - Lederherstellung, Hautleim- und Gelatineindustrie - Fischmehlfabriken - Papier- und Zellstoffindustrie - Textilindustrie - Kfz-Werkstaetten - Eisenbahn - Kfz-Waesche - Militaer, Entkonservierung - Transportbehaelterinnenreinigung - Gewerbliche Waescherei und Textilreinigung - Sickerwasser aus Abfallanlagen - Krankenhausabwasser. Jedes Kapitel beginnt mit einer Uebersicht ueber die Bedeutung der Branche, ihre Kapazitaet sowie deren Fertigerzeugnisse. Die Produktionsschritte und -techniken werden erlaeutert, wobei in Fliessschemata auch alle beteiligten Stoffstroeme dargestellt sind. Abwasserrelevante Teilstroeme werden analysiert und der immer mehr an Bedeutung zunehmende produktionsintegrierte Umweltschutz entsprechend gewichtet. Die verfahrenstechnischen Moeglichkeiten der Abwasserbehandlung - Vorbehandlung, Indirekt- und Direkteinleitung - werden aufgezeigt. Anwendungsbeispiele aus der Praxis, die neben der Verfahrenstechnik auch Anlagen zu

  14. The auditory organ: active amplifier and highly sensitive measuring system; Das Hoerorgan: Aktiver Schallverstaerker und hochempfindliches Messsystem

    Energy Technology Data Exchange (ETDEWEB)

    Kafka-Luetzow, A. [Univ. Wien (Austria). Inst. fuer Allgemeine und Vergleichende Physiologie

    1997-12-01

    The present paper provides a brief review on topical issues of auditory physiology. Recent data on transduction mechanism and adaptation in hair cells as well as on the possible role of outer hair cells in amplifying basilar membrane motion are presented. Strategies of present physiological research in dealing with sensorineural deafness are discussed. (orig.) [Deutsch] Neuere Erkenntnisse der Hoerphysiologie haben einige der Mechanismen aufgezeigt, welche fuer die hohe Empfindlichkeit, die gute Frequenzdiskrimination und das bei Lautstaerkenerhoehung nicht lineare Verhalten dieses Sinnessystems verantwortlich sein duerften. Demnach haben die 2 Typen akustischer Sinneszellen voellig unterschiedliche Funktionen. Nur ein Typ, die Inneren Haarzellen, duerften Sensoren im engeren Sinn sein, indem sie die wesentliche akustische Information an das Zentralnervensystem liefern. Der zweite Typ, die Aeusseren Haarzellen scheinen vornehmlich als Eingangsverstaerker zu fungieren. Sie setzen die bei Schalleinwirkung auf das Ohr an ihrer Membran auftretende Potentialaenderung in rasche Laengskontraktionen um. Damit verstaerken sie die durch die Schalleinwirkung ausgeloesten Basilarmembranschwingungen. Ausserdem duerften die von den Aeusseren Haarzellen aktiv erzeugten Schwingungen die Quelle der im aeusseren Gehoergang messbaren `otoakustischen Emissionen` sein. Die gegenstaendliche Uebersicht fasst den aktuellen Wissensstand ueber den Transduktionsmechanismus und die Elektromotilitaet der Haarzellen zusammen. Darueber hinaus wird die moegliche auditive Funktion von Haarzellen im Gleichgewichtssystem sowie Befunde aus der in den letzten Jahren entbrannten Diskussion um eine allfaellige Regeneration von Haarzellen aus dem vestibulocochleaeren System von adulten Saeugern diskutiert. Im Zusammenhang mit der Druckausbreitung im Innenohr werden einige morphologische Besonderheiten insbesonders der cochleaeren Fluessigkeitsraeume und ihrer Verbindungen sowie deren funktionelle

  15. Current developments in DICOM and IHE; Aktuelle Entwicklungen von DICOM und IHE

    Energy Technology Data Exchange (ETDEWEB)

    Mildenberger, P. [Johannes-Gutenberg-Universitaet Mainz, Klinik fuer Radiologie (Germany); Wein, B. [Universitaetsklinikum Aachen, Klinik fuer Radiologische Diagnostik (Germany); Bursig, H.-P. [ZVEI (Zentralverband der Elektroindustrie), Frankfurt (Germany); Eichelberg, M. [OFFIS (Oldenburger Forschungs- und Entwicklungsinstitut fuer Informatikwerkzeuge und -systeme) (Germany)

    2005-08-01

    The broadening use of imaging management systems in radiology and other disciplines is due in large part to the success of the DICOM standard (Digital Imaging and Communications in Medicine), which has been accepted worldwide for more than 10 years and meanwhile represents one of the most successful standards in medicine. The central intent of establishing the initiative ''Integrating the Healthcare Enterprise'' (IHE) was to ensure interoperability of different IT systems in medical processes. IHE is essentially based on widespread standards such as DICOM or HL7. This overview article briefly addresses the principles and organization of DICOM and IHE and describes the current developments in both domains. (orig.) [German] Die zunehmende Verbreitung von Bildmanagementsystemen in der Radiologie und anderen Faechern basiert ganz wesentlich auf dem Erfolg des DICOM-Standards (Digital Imaging and Communication in Medicine), der seit mehr als 10 Jahren weltweit akzeptiert ist und inzwischen einen der erfolgreichsten Standards in der Medizin darstellt. Die Etablierung der Initiative ''Integrating the Healthcare Enterprise'' (IHE) 1998 hat als zentrales Anliegen das Zusammenwirken unterschiedlicher IT-Systeme (Interoperabilitaet) im medizinischen Ablauf sicherzustellen. Dabei baut IHE im Wesentlichen auf weit verbreiteten Standards wie DICOM oder HL7 auf. In dieser Uebersicht wird jeweils kurz auf die Grundlagen und Organisation von DICOM bzw. IHE eingegangen sowie die aktuellen Entwicklungen beider Bereiche dargestellt. (orig.)

  16. 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

  17. Mitochondrial replacement techniques and Mexico's rule of law: on the legality of the first maternal spindle transfer case

    Science.gov (United States)

    Medina-Arellano, María de Jesús

    2017-01-01

    Abstract News about the first baby born after a mitochondrial replacement technique (MRT; specifically maternal spindle transfer) broke on September 27, 2016 and, in a matter of hours, went global. Of special interest was the fact that the mitochondrial replacement procedure happened in Mexico. One of the scientists behind this world first was quoted as having said that he and his team went to Mexico to carry out the procedure because, in Mexico, there are no rules. In this paper, we explore Mexico's rule of law in relation to mitochondrial replacement techniques and show that, in fact, certain instances of MRTs are prohibited at the federal level and others are prohibited at the state level. According to our interpretation of the law, the scientists behind this first successful MRT procedure broke federal regulations regarding assisted fertilization research. PMID:28852557

  18. Mechanism-based model of a mass rapid transit system: A perspective

    Science.gov (United States)

    Legara, Erika Fille; Khoon, Lee Kee; Guang, Hung Gih; Monterola, Christopher

    2015-01-01

    In this paper, we discuss our findings on the spatiotemporal dynamics within the mass rapid transit (MRT) system of Singapore. We show that the trip distribution of Origin-Destination (OD) station pairs follows a power-law, implying the existence of critical OD pairs. We then present and discuss the empirically validated agent-based model (ABM) we have developed. The model allows recreation of the observed statistics and the setting up of various scenarios and their effects on the system, such as increasing the commuter population and the propagation of travel delays within the transportation network. The proposed model further enables identification of bottlenecks that can cause the MRT to break down, and consequently provide foresight on how such disruptions can possibly be managed. This can potentially provide a versatile approach for transport planners and government regulators to make quantifiable policies that optimally balance cost and convenience as a function of the number of the commuting public.

  19. 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.)

  20. 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