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Sample records for verge bogdanov mrt

  1. The life and death of Alexander Bogdanov, physician.

    Science.gov (United States)

    Huestis, D W

    1996-08-01

    It was early in April in 1928 when the word went out in Moscow that Alexander Bogdanov had died. He was a controversial figure, an old Bolshevik who had left that party long before the 1917 revolution and never returned. All the same, he had had Lenin's respect as a scientist (as long as he stayed out of politics). More recently, he also had the support of the new party strong man, Stalin. Bogdanov opposed the growing despotism of the "dictatorship of the proletariat", under which slogan Communist autocracy was being developed. But he was respected as a tireless propagandist for the socialist cause, an enthusiastic teacher of the proletariat, and a writer of arcane science and philosophy. Bogdanov was held in such respect that Communist bigwigs spoke glowingly at the funeral, praising his intellect, courage, and dedication to science and humanity. They did not fail to point out that he had split with his one-time friend, Lenin, and had succumbed to ideological "errors". Indeed, he had powerful enemies in the early Soviet state. Bogdanov was a physician, economist, philosopher, natural scientist, writer of utopian science fiction, poet, teacher, politician (unsuccesful), lifelong revolutionary, forerunner of what we now call cybernetics and organizational science, and founder of the world's first institution devoted entirely to the field of blood transfusion. You could call him a Renaissance man. Although he clearly fitted the category of the late-nineteenth-century Russian intellectual revolutionary, Bogdanov differed from most of them in being no dilettante. More than just a theorist, he was an active scientist and physician. As a teacher, he firmly believed that education and indoctrination could alter people's ways of thinking and behaving, and that humanity could be perfected under socialism. Like many revolutionaries, Bogdanov tried to keep ahead of the Tsar's police by using a variety of pseudonyms, among them Riadavoy, Werner, Maximov, and Bogdanov. After

  2. Improved homoclinic predictor for Bogdanov-Takens bifurcation

    NARCIS (Netherlands)

    Kuznetsov, Yuri; Meijer, Hil; Al Hdaibat, Bashir; Govaerts, Willy

    2014-01-01

    An improved homoclinic predictor at a generic codim 2 Bogdanov-Takens (BT) bifucation is derived. We use the classical ‘blow-up’ technique to reduce the canonical smooth normal form near a generic BT bifurcation to a perturbed Hamiltonian system. With a simple perturbation method, we derive explicit

  3. A Degenerate Bogdanov-Takens Normal Form for FLRW Cosmologies

    CERN Document Server

    Kohli, Ikjyot Singh

    2016-01-01

    In this paper, we first show that the Einstein field equations for all perfect-fluid FLRW cosmologies can be written as a planar dynamical system with the equation of state parameter $w$ and cosmological constant $\\Lambda$ as parameters. An important equilibrium point of this dynamical system is the origin which represents Minkowski spacetime. It is shown that the Einstein field equations in a neigbourhood of this point are equivalent to a degenerate Bogdanov-Takens normal form. This normal form admits a set of equilibrium points that describes a set of solutions to the Einstein field equations that have a constant rate of expansion, negative spatial curvature, zero cosmological constant and dust.

  4. A Note on the Bogdanov-Takens Bifurcation in the Romer Model with Learning by Doing

    Science.gov (United States)

    Bella, Giovanni

    This paper is aimed at describing the whole set of necessary and sufficient conditions for the emergence of multiple equilibria and global indeterminacy in the standard endogenous growth framework with learning by doing. The novelty of this paper relies on the application of the original Bogdanov-Takens bifurcation theorem, which allows us to characterize the full dynamics of the model, and determine the emergence of an unavoidable poverty trap.

  5. DE VERGE. A PROPOS DE 39 CAS.

    African Journals Online (AJOL)

    et 5 coudures secondaires à la maladie de. Lapeyronie) elle siégeait au 1/3 postérieur de la verge. Direction de la coudure: La coudure était ventrale (gland dirigé en bas) dans 16 cas (9 coudures congénitales et. 7 coudures secondaires à la maladie de La- peyronie). Elle était dorsale (gland dirigé en haut) dans 12 cas (6 ...

  6. MRI survival guide; MRT Basiskurs

    Energy Technology Data Exchange (ETDEWEB)

    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

  7. Solving significant problems in social utopias A. Bogdanov as a prelude to globalization

    OpenAIRE

    Пустовойт, В.І.; Верховна Рада України

    2009-01-01

     In the context of global problems considered utopian projects of the Russian philosopher, politician, writer Alexander Bogdanov (Malinovsky).  В контексте глобальных проблем современности рассмотрены утопические проекты русского философа, политического деятеля, писателя Александра Богданова (Малиновского).  У контексті глобальних проблем сучасності розглянуті утопічні проекти російського філософа, політичного діяча, письменника Олександра Богданова (Малиновського)....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-07-01

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

  9. The ecology of macromycetes in roadside verges planted with trees

    NARCIS (Netherlands)

    Keizer, P.J.

    1993-01-01

    In this thesis phytocoena and mycocoena of ectomycorrhizal fungi and saprotrophic fungi in roadside verges planted with trees are described independently. An attempt is made to indicate which environmental variables are most important in the distinguished communities. Parasitic fungi on

  10. Amputation Totale de La Verge: A Propos de Trois Observations ...

    African Journals Online (AJOL)

    Conclusion: qu'elle soit d'origine criminelle ou psychogène, l'amputation totale du pénis est rarissime. Les conséquences sont urinaires, sexuelles et psychogènes. La prise en charge doit être multidisciplinaire. Mots Clés: Verge; amputation; méat; sténose. English Title: Total penile amputation: a report on three cases.

  11. [MRT diagnosis for degenerative changes in the spine].

    Science.gov (United States)

    Kahn, T; Quäschling, U; Engelbrecht, V

    2004-08-01

    MRT is very well suited to the diagnosis of degenerative alterations in the spine. The option of imaging in multiple planes, the excellent soft-tissue contrast offering tissue differentiation, the absence of hardening artefacts and the avoidance of exposure to radiation have led to a shift in favour of MRT for diagnosis. In the present paper the MRT characteristics of the most important degenerative alterations that affect the spine are discussed.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-02-01

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

  13. MRI for myocarditis; MRT bei Myokarditis

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-01-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-11-01

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

  15. 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.)

  16. MRI of pulmonary perfusion; MRT der Lungenperfusion

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-04-15

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

  17. COBISS on the verge of its second decade

    Directory of Open Access Journals (Sweden)

    Marta Seljak

    1997-01-01

    Full Text Available Projects, products and services, developed over the 10-year existence of the COBISS system, are presented. Special emphasis is given to the timing in regard to solving specific shared cataloguing technical issues. Numerical indicators as to the production of bibliographic records in the shared COBIB database during the same period are presented. Plans and goals on the verge of the second decade of the COBISS system are outlined: plans particularly relating to the technological modernization of the COBISS system, the establishment of two global services,authority control and electronic ordering of library materials; and plans relating to the automation of the local library functions: interlibrary loan, acquisition and serials check-in.

  18. The rightful place of science science on the verge

    CERN Document Server

    2016-01-01

    A crisis looms over the scientific enterprise. Not a day passes without news of retractions, failed replications, fraudulent peer reviews, or misinformed science-based policies. The social implications are enormous, yet this crisis has remained largely uncharted—until now. In Science on the Verge, luminaries in the field of post-normal science and scientific governance focus attention on worrying fault-lines in the use of science for policymaking, and the dramatic crisis within science itself. This provocative new volume in The Rightful Place of Science also explores the concepts that need to be unlearned, and the skills that must be relearned and enhanced, if we are to restore the legitimacy and integrity of science.

  19. The Bogdanov Affair

    CERN Multimedia

    Baez, John

    2002-01-01

    We all laughed when the physicist Alan Sokal wrote a deliberately silly paper entitled "Transgressing the boundaries: towards a transformative hermeneutics of quantum gravity" and managed to get it accepted by a refereed journal of social and cultural studies, Social Text. But, after, we learned that two brothers got Ph. D in physics on the basis of this work (4 pages)

  20. 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.)

  1. Ground-dwelling arthropod (Araneae, Coleoptera: Carabidae, Isopoda: Oniscidea assemblages on Hungarian main road verges

    Directory of Open Access Journals (Sweden)

    Vona-Túri Diána

    2016-12-01

    Full Text Available In this study, we research ground-dwelling arthropods along four road stretches, which represent the main verge habitats (arid grassland, agricultural area, forest, and wetland of Hungary. Besides the faunistic investigation of arthropod communities, we described and compared dominance relation and species composition. We identified 83 carabids, 81 spiders, and 4 isopod species. Seven beetle species and one spider species are included in the invertebrate Red List of Hungary. The registered species were dominant on main road verges bordering arid grassland and wetland. Main road verges proved to be a diverse habitat; hence, it is important to carry on more investigation.

  2. Face Transplantation: On the Verge of Becoming Clinical Routine?

    Directory of Open Access Journals (Sweden)

    Ralf Smeets

    2014-01-01

    Full Text Available Introduction. Face transplantation (FT is an innovative achievement of modern reconstructive surgery and is on the verge of becoming a common surgical opportunity. This review article was compiled to provide an update on this surgical field, especially regarding clinical outcomes, benefits, and complications implied. Methods. We performed an extensive research on all English-language Medline articles, case reports, and reviews published online until September 15, 2013. Used search terms were “face transplantation,” “face transplant,” “facial transplantation,” “facial transplant,” “face allograft,” and “facial allograft.” Results. To date 27 FTs have been performed worldwide. 19 of these cases have been published in the Medline database. Long-term follow-up reports of FT cases are rare. Three deaths associated with the procedure have occurred to date. The clinical outcomes of FT are satisfying. Reinnervation of sensation has been faster than motor recovery. Extensive functional improvements have been observed. Due to strict immunosuppression protocols, no case of hyperacute or chronic rejection and no graft-versus-host disease have occurred to date. Conclusions. As studies on long-term outcomes are missing, particularly regarding immunosuppression-related complications, FT will stay experimental for the next years. Nevertheless, for a small group of patients, FT already is a feasible reconstructive option.

  3. Road verges and winter wheat fields as resources for wild bees in agricultural landscapes

    DEFF Research Database (Denmark)

    Henriksen, Casper Christian I; Langer, Vibeke

    2013-01-01

    The effects of farming system on plant density and flowering of dicotyledonous herbs of high value for bees were investigated in 14 organic and 14 conventional winter wheat fields and adjacent road verges. The organic and conventional winter wheat fields/road verges were paired based on the perce......The effects of farming system on plant density and flowering of dicotyledonous herbs of high value for bees were investigated in 14 organic and 14 conventional winter wheat fields and adjacent road verges. The organic and conventional winter wheat fields/road verges were paired based...... on the percentage of semi-natural habitats in the surrounding landscape at 1-km scale. Mean density of high value bee plants per Raunkiaer circle was significantly higher in organic winter wheat fields and their adjacent road verges than in their conventionally farmed counterparts. The effect of organic farming...... was even more pronounced on the flowering stage of high value bee plants, with 10-fold higher mean density of flowering plants in organic fields than in conventional fields and 1.9-fold higher in road verges bordering organic fields than in those bordering conventional fields. In summary, organic farming...

  4. Effect of different mowing regimes on butterflies and diurnal moths on road verges

    Directory of Open Access Journals (Sweden)

    Valtonen, A.

    2006-12-01

    Full Text Available In northern and central Europe road verges offer alternative habitats for declining plant and invertebrate species of semi-natural grasslands. The quality of road verges as habitats depends on several factors, of which the mowing regime is one of the easiest to modify. In this study we compared the Lepidoptera communities on road verges that underwent three different mowing regimes regarding the timing and intensity of mowing; mowing in mid-summer, mowing in late summer, and partial mowing (a narrow strip next to the road. A total of 12,174 individuals and 107 species of Lepidoptera were recorded. The mid-summer mown verges had lower species richness and abundance of butterflies and lower species richness and diversity of diurnal moths compared to the late summer and partially mown verges. By delaying the annual mowing until late summer or promoting mosaic-like mowing regimes, such as partial mowing, the quality of road verges as habitats for butterflies and diurnal moths can be improved.

  5. 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).

  6. G-DRG-Zuordnung und Vergütung der Kyphoplastie in 2010

    OpenAIRE

    Selter DD

    2010-01-01

    Seit der verpflichtenden Einführung des G-DRG-Systems in der BRD im Jahre 2004 wurde die DRG-Zuordnung und Vergütung der Kyphoplastie jährlich angepasst. Die korrekte DRG-Zuordnung und Abrechnung der Kyphoplastie ist eng mit der Kodierung der Fälle mit den korrekten Codes der Diagnosen- und Prozedurenklassifikation unter Berücksichtigung der Deutschen Kodierrichtlinien verbunden. Es ist festzustellen, dass sich die DRG-Vergütung zunehmend dem Aufwand und den damit verbundenen Koste...

  7. G-DRG-Zuordnung und Vergütung der Kyphoplastie in 2010

    Directory of Open Access Journals (Sweden)

    Selter DD

    2010-01-01

    Full Text Available Seit der verpflichtenden Einführung des G-DRG-Systems in der BRD im Jahre 2004 wurde die DRG-Zuordnung und Vergütung der Kyphoplastie jährlich angepasst. Die korrekte DRG-Zuordnung und Abrechnung der Kyphoplastie ist eng mit der Kodierung der Fälle mit den korrekten Codes der Diagnosen- und Prozedurenklassifikation unter Berücksichtigung der Deutschen Kodierrichtlinien verbunden. Es ist festzustellen, dass sich die DRG-Vergütung zunehmend dem Aufwand und den damit verbundenen Kosten angepasst hat, und dennoch Verbesserungspotenzial bestehen bleibt.

  8. Cardio-MRT. Technique and topographic-anatomic considerations

    Energy Technology Data Exchange (ETDEWEB)

    Lackner, K.; Steudel, A.; Krahe, T.; Becher, H.; Gieseke, J.; Thurn, P.

    1987-03-01

    ECG-triggered cardio-MRT, using T/sub 1/-weighted SE sequences, provides images of the heart showing very high anatomical resolution. So far, however, it has not been possible to demonstrate the morphology of the valves and coronary vessels. By using multiplanar sections, it is possible to obtain cuts which are perpendicular to the portion of myocardium or valve under consideration. This provides optimal imaging for morphological diagnosis and for evaluating the ventricular myocardium and its function.

  9. Sex, Milk and Death: The Enigma Sexuality | Vergès | CODESRIA ...

    African Journals Online (AJOL)

    Sex, Milk and Death: The Enigma Sexuality. Françoise Vergès. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use · Contact AJOL · News. OTHER RESOURCES... for Researchers · for Journals ...

  10. Optimizing grassland management for flower-visiting insects in roadside verges

    NARCIS (Netherlands)

    Noordijk, J.; Schaffers, A.P.; Delille, K.; Sykora, K.V.

    2009-01-01

    The decline of flower-visiting insects is a threat to ecological processes and to the services these insects provide. Roadside verges in the Netherlands span approximately 80,000 km and are often covered with semi-natural grasslands. As such, they also provide a suitable habitat for many insects,

  11. Medicinal formulations of a Kanda tribal healer – a tribe on the verge ...

    African Journals Online (AJOL)

    The Kanda tribe is one of the lesser known small tribes of Bangladesh with an estimated population of about 1700 people (according to them), and on the verge ... Besides medicinal plants, the Kanda healer also used the body hairs of the Asiatic black bear (Ursus thibetanus) and bats (Pteropus giganteus giganteus) in one ...

  12. 3D imaging using magnetic resonance tomosynthesis (MRT) technique.

    Science.gov (United States)

    Kim, Min-Oh; Zho, Sang-Young; Kim, Dong-Hyun

    2012-08-01

    To introduce an alternative approach to three-dimensional (3D) magnetic resonance (MR) imaging using a method that is similar to x-ray tomosynthesis. Variable angle tilted-projection images are acquired using a multiple-oblique view (MOV) pulse sequence. Reconstruction is performed using three methods similar to that of x-ray tomosynthesis, which generate a set of tomographic images with multiple 2D projection images. The reconstruction algorithm is further modified to reformat to the practical imaging situations of MR. The procedure is therefore termed magnetic resonance tomosynthesis (MRT). To analyze the characteristics of MRT, simulations are performed. Phantom and in vivo experiments were done to suggest potential applications. Simulation results show anisotropic features that are structurally dependent in terms of resolution. Partial blurrings along slice direction were observed. In phantom and in vivo experiments, the reconstruction performance is particularly noticeable in the low SNR case where improved images with lower noise are obtained. Reformatted reconstruction using thinner slice thickness and∕or extended field-of-view can increase spatial resolution partially and alleviate slice profile imperfection. Results demonstrate that MRT can generate adequate 3D images using the MOV images. Various reconstruction methods in tomosynthesis were readily adapted, while allowing other tomosynthesis reconstruction algorithms to be incorporated. A reformatted reconstruction process was incorporated for applications relevant to MR imaging.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-04-01

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

  14. MRI for chronic inflammatory bowel disease; MRT chronisch entzuendlicher Darmerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Hansmann, H.J.; Hess, T.; Hahmann, M.; Erb, G.; Richter, G.M.; Duex, M. [Heidelberg Univ. (Germany). Abt. Roentgendiagnostik; Elsing, C. [Heidelberg Univ. (Germany). Abt. IV - Gastroenterologie

    2001-01-01

    Chronic inflammatory bowel disease is diagnosed and monitored by the combination of colonoscopy and small bowel enteroklysis. Magnetic resonance imaging has become the gold standard for the imaging of perirectal and pelvic fistulas. With the advent of ultrafast MRI small and large bowel imaging has become highly attractive and is being advocated more and more in the diagnostic work up of inflammatory bowel disease. Imaging protocols include fast T{sub 1}-weighted gradient echo and T{sub 2}-weighted TSE sequences and oral or rectal bowel distension. Furthermore, dedicated imaging protocols are based on breath-hold imaging under pharmacological bowel paralysis and gastrointestinal MR contrast agents (Hydro-MRI). High diagnostic accuracy can be achieved in Crohn's disease with special reference to the pattern of disease, depth of inflammation, mesenteric reaction, sinus tract depiction and formation of abscess. In ulcerative colitis, the mucosa-related inflammation causes significantly less bowel wall thickening compared to Crohn's disease. Therefore with MRI, the extent of inflammatory changes is always underestimated compared to colonoscopy. According to our experience in more than 200 patients as well as the results in other centers, Hydro-MRI possesses the potential to replace enteroklysis in the diagnosis of chronic inflammatory bowel disease and most of the follow-up colonoscopies in Crohn's disease. Further technical improvements in 3D imaging will allow interactive postprocessing of the MR data. (orig.) [German] Zusammenfassung: Die Standardverfahren in der Diagnostik und der Verlaufskontrolle chronisch entzuendlicher Darmerkrankungen, speziell des Morbus Crohn und der Colitis ulcerosa, sind die Koloskopie und das Enteroklysma. Die MRT hat sich dazu ihren festen Platz in der Diagnostik perirektaler Fisteln erobert. Mit schnellen, T{sub 1}-gewichteten Gradienten-Echo-Sequenzen und T{sub 2}-gewichteten Turbo-Spin-Echo-Sequenzen koennen auch Duenn

  15. Legg-Calve-Perthes' disease. Ranking of MRT in early diagnosis and course assessment. M. Legg-Calve-Perthes. Wertigkeit der MRT in der Fruehdiagnostik und Verlaufsbeurteilung

    Energy Technology Data Exchange (ETDEWEB)

    Rix, J.; Maas, R. (Universitaetskrankenhaus Eppendorf, Hamburg (Germany). Abt. Roentgendiagnostik); Eggers-Stroeder, G.; Bruns, J. (Universitaetskrankenhaus Eppendorf, Hamburg (Germany). Orthopaedische Klinik)

    1992-01-01

    We report on the value of MRT in diagnosis and follow-up of Perthes' disease. 38 children who were clinically suspect of suffering from Perthes' disease were examined by conventional X-ray and MRT. 25 children were proven to have Perthes' disease 12 of them in an early stage. During the onset of the disease MRT showed a higher sensitivity (58% vs 50%) and accuracy (74% vs 71%) than conventional X-ray while specificity was equal (83% for both). Additionally, MRT in combination with the still obligatory X-ray gave no false-positive results. In some cases, the diagnosis may be found up to 6 weeks earlier using MRT. Conservative therapeutic regimes obviously will not profit from this. Although excluding other diseases is certainly helpful, the value of MRT as a primary diagnostic procedure is limited. During follow-up, MRT helps to reduce the number of X-ray examinations since it can easily assess the containment of the hip and the bone marrow revitalisation. Scintigraphy, another valuable method to judge revitalisation, should remain limited to selected cases, as it requires significant amounts of radiation. (orig.).

  16. 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

  17. 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.)

  18. Optimising UK urban road verge contributions to biodiversity and ecosystem services with cost-effective management.

    Science.gov (United States)

    O'Sullivan, Odhran S; Holt, Alison R; Warren, Philip H; Evans, Karl L

    2017-04-15

    Urban road verges can contain significant biodiversity, contribute to structural connectivity between other urban greenspaces, and due to their proximity to road traffic are well placed to provide ecosystem services. Using the UK as a case study we review and critically evaluate a broad range of evidence to assess how this considerable potential can be enhanced despite financial, contractual and public opinion constraints. Reduced mowing frequency and other alterations would enhance biodiversity, aesthetics and pollination services, whilst delivering costs savings and potentially being publically acceptable. Retaining mature trees and planting additional ones is favourable to residents and would enhance biodiversity, pollution and climate regulation, carbon storage, and stormwater management. Optimising these services requires improved selection of tree species, and creating a more diverse tree stock. Due to establishment costs additional tree planting and maintenance could benefit from payment for ecosystem service schemes. Verges could also provide areas for cultivation of biofuels and possibly food production. Maximising the contribution of verges to urban biodiversity and ecosystem services is economical and becoming an increasingly urgent priority as the road network expands and other urban greenspace is lost, requiring enhancement of existing greenspace to facilitate sustainable urban development. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Spanish-Speaking Students and the Language Factor in the MRT

    Science.gov (United States)

    Cruz, Sylvia; And Others

    1975-01-01

    Discusses a study designed to examine the effect of translating the Metropolitan Readiness Test (MRT) for Spanish speaking school entrants, to determine whether administering the MRT in Spanish makes a significant difference on the scores of Spanish-speaking students, and whether these differences obtain for students in bilingual and all-English…

  20. 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

  1. 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.)

  2. Clarice Lispector e Vergílio Ferreira: a existência problematizada = Clarice Lispector and Vergílio Ferreira: problematizing existence

    Directory of Open Access Journals (Sweden)

    Evely Vânia Libanori

    2010-01-01

    Full Text Available A obra da escritora brasileira Clarice Lispector (1925-1977 e a produção literária do escritor português Vergílio Ferreira (1916-1996, iniciada a partir da publicação do romance Mudança, em 1969, apresentam semelhanças no que diz respeito tanto à exposiçãodos temas quanto ao processo de construção textual. As obras desses escritores são marcadas pela análise introspectiva, por isso prevalecem a constatação sobre a vida em curso, o sentimento de solidão existencial e o questionamento sobre a morte. O presente artigo consiste na exposição da trajetória existencial de Lóri em Uma aprendizagem ou O livro dos prazeres, de Lispector, e Alberto Soares em Aparição, de Vergílio Ferreira. Para tanto, nosso suporte teórico principal será o tratado filosófico Ser e tempo, de Martin Heidegger. Segundo Heidegger, só é possível entender a natureza humana em seu incessante movimento de interação consigo mesma, com outras pessoas e com os objetos ao seu redor. Assim sendo, é necessário delinear a identidade do homem que rompe as vinculações fáticas com os objetose seres ao redor e se vê como o fundador de si e do mundo. The work by Brazilian writer Clarice Lispector (1925-1977 and the literary production of Portuguese writer Vergílio Ferreira (1916-1996, initiated with the publication of the novel Mudança, in 1969, present similarities in theme exposition as well as the process of text construction. The works of these two writers are marked by the introspective analysis in which prevail the evidence of life in its course, the feeling of existential loneliness, and the questioning of death. The present article consists in the exposition of the existential course of Lóri in Uma aprendizagem ou O livro dos prazeres, by Clarice Lispector, and Alberto Soares in Aparição, by Vergílio Ferreira. In order to do that, our main theoretical apparatus will be the philosophical treaty Ser e tempo, by Martin Heidegger. According to

  3. 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

  4. Asymptotic Analysis in MIMO MRT/MRC Systems

    Directory of Open Access Journals (Sweden)

    Zhou Quan

    2006-01-01

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

  5. Lead concentrations and reproductive success in European starlings Sturnus vulgaris nesting within highway roadside verges

    Energy Technology Data Exchange (ETDEWEB)

    Grue, C.E.; Hoffman, D.J.; Beyer, W.N.; Franson, L.P.

    1986-01-01

    In 1981, the authors studied lead concentrations and reproductive success in free-living European starlings Sturnus vulgaris nesting within the verges of two Maryland highways with different traffic volumes, Route 197 and the Baltimore-Washington Parkway and a nearby control area. Concentrations of lead in the ingesta, carcassses and feathers of Parkway nestlings and adults were 3 to 13 times those found in starlings from the control area, whereas lead concentrations in the ingesta and tissues of starlings from the verge of Route 197 were similar to those of controls. Activity of delta-aminolevulinic acid dehydratase (ALAD) in red blood cells (RBCs) of adult and nestling starlings from the Parkway was depressed from 43 to 60% compared to controls. RBC ALAD activity in adults from nests along Route 197 was similar to that of adult starlings from the control area, but that of their young was depressed 17%. Haemoglobin concentrations (-16%) and haematocrits (-10%) in parkway nestlings were depressed compared with those of nestlings from the other two study areas, whereas those of adults were not affected. Clutch size, number of young hatched and the number of young in nests 1 to 3 days before fledging were similar among sites, as were body weights of adults and prefledging weights of their young. However, brain weights of Parkway nestlings were lower (P < 0.05) than those of nestlings from the other study areas. Results suggests that lead within verges of major highways probably does not pose a serious hazard to adult ground-foraging songbirds. However, the effects of lead-induced reductions in haemoglobin concentration, haematocrit, RBC ALAD activity and brain weight on the postfledging survival of their young are not known.

  6. 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

  7. La teoría de la vergüenza reintegrativa de John Braithwaite

    Directory of Open Access Journals (Sweden)

    Miguel Langón Cuñarro

    2014-11-01

    Full Text Available Este importante autor australiano presenta una de las últimas teorías criminólogas, dentro del grupo de teorías integradoras, que no debería ser desconocida por los operadores, sobre todo porque, más allá del alcance explicativo que tenga sobre la criminalidad, es obvio. que presenta una riqueza tal de contenido, que puede ser de aplicación en numerosas áreas de tratamiento de infractores.Su concepción del hecho criminal y el tratamiento se divide entre: a una concepción o teoría republicana de la Justicia criminal, que es de tipo normativo, y refiere al deber. ser, que postula como propio de los sistemas democráticos de justicia penal que el derecho a castigar sólo puede ser admisible cuando ello incrementa la libertad republicana en la sociedad, y, b la teoría de la vergüenza reintegradora que es una teoría del ser, que intenta ser de carácter explicativa, y que se opone, como se verá a la vergüenza "desintegradora" que deriva de la estigmatización.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-02-01

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

  9. Identification and mechanism of action of the acylguanidine MRT-83, a novel potent Smoothened antagonist.

    Science.gov (United States)

    Roudaut, Hermine; Traiffort, Elisabeth; Gorojankina, Tatiana; Vincent, Ludwig; Faure, Helene; Schoenfelder, Angele; Mann, Andre; Manetti, Fabrizio; Solinas, Antonio; Taddei, Maurizio; Ruat, Martial

    2011-03-01

    There is a clear need to develop novel pharmacological tools to improve our understanding of Smoothened (Smo) function in normal and pathological states. Here, we report the discovery, the mechanism of action, and the in vivo activity of N-(2-methyl-5-(3-(3,4,5-trimethoxybenzoyl)guanidino)phenyl)biphenyl-4-carboxamide (MRT-83), a novel potent antagonist of Smo that belongs to the acylguanidine family of molecules. MRT-83 fits to a proposed pharmacophoric model for Smo antagonists with three hydrogen bond acceptor groups and three hydrophobic regions. MRT-83 blocks Hedgehog (Hh) signaling in various assays with an IC50 in the nanomolar range, showing greater potency than the reference Smo antagonist cyclopamine. MRT-83 inhibits Bodipy-cyclopamine binding to human and mouse Smo but does not modify Wnt signaling in human embryonic kidney 293 transiently transfected with a Tcf/Lef-dependent Firefly luciferase reporter together with a Renilla reniformis luciferase control reporter. MRT-83 abrogates the agonist-induced trafficking of endogenous mouse or human Smo to the primary cilium of C3H10T1/2 or NT2 cells that derive from a pluripotent testicular carcinoma. Stereotaxic injection into the lateral ventricle of adult mice of MRT-83 but not of a structurally related compound inactive at Smo abolished up-regulation of Patched transcription induced by Sonic Hedgehog in the neighboring subventricular zone. These data demonstrate that MRT-83 efficiently antagonizes Hh signaling in vivo. All together, these molecular, functional and biochemical studies provide evidence that MRT-83 interacts with Smo. Thus, this novel Smo antagonist will be useful for manipulating Hh signaling and may help develop new therapies against Hh-pathway related diseases.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-03-01

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

  11. MRT-2 checkpoint protein is required for germline immortality and telomere replication in C. elegans.

    Science.gov (United States)

    Ahmed, S; Hodgkin, J

    2000-01-13

    The germ line is an immortal cell lineage that is passed indefinitely from one generation to the next. To identify the genes that are required for germline immortality, we isolated Caenorhabditis elegans mutants with mortal germ lines--worms that can reproduce for several healthy generations but eventually become sterile. One of these mortal germline (mrt) mutants, mrt-2, exhibits progressive telomere shortening and accumulates end-to-end chromosome fusions in later generations, indicating that the MRT-2 protein is required for telomere replication. In addition, the germ line of mrt-2 is hypersensitive to X-rays and to transposon activity. Therefore, mrt-2 has defects in responding both to damaged DNA and to normal double-strand breaks present at telomeres. mrt-2 encodes a homologue of a checkpoint gene that is required to sense DNA damage in yeast. These results indicate that telomeres may be identified as a type of DNA damage and then repaired by the telomere-replication enzyme telomerase.

  12. MRT diagnosis of cardiac myxomas: sequence evaluation and differential diagnosis; MRT-Diagnostik kardialer Myxome: Sequenzevaluierung und Differentialdiagnose

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, T.; Hofer, U.; Pauleit, D.; Wilhelm, K.; Textor, J.; Schild, H. [Bonn Univ. (Germany). Radiologische Klinik; Vahlhaus, C. [Bonn Univ. (Germany). Medizinische Poliklinik; Smekal, A. v. [UniversitaetsSpital Zuerich, Zurich (Switzerland). Inst. fuer Diagnostische Radiologie; Wardelmann, E.; Bierhoff, E. [Bonn Univ. (Germany). Pathologisches Inst.

    1999-02-01

    Purpose: To evaluate native and contrast enhanced T{sub 1}-weighted spin (T{sub 1}-SE), cine gradient echo (Cine-GE), and T{sub 2}-weighted turbo spin (T{sub 2}-TSE) sequences in the diagnosis and differential diagnosis of cardiac myxomas. Methods: 15 patients with echocardiographically suspected cardiac arterial myxomas underwent 0,5 T-MR imaging of the heart with native T{sub 1}-SE, contrast-enhanced T{sub 1}-SE, Cine-GE, and T{sub 2}-TSE sequences. MR images were evaluated for signal intensity (SI) and lesion`s conspicuity. Results were confirmed histologically (14x) or by follow-up (1x). Results: MRI revealed myxomas in 9 patients, sarcomas in three patients, and thrombi in three patients. Lesion conspicuity was better in Cine-GE and T{sub 2}-TSE compared with native and contrast-enhanced T{sub 1}-SE sequences. Myxomas were characterized by an intermediate SI similar to myocardium in T{sub 1}-SE, high SI similar to water in T{sub 2}-TSE, and low to moderately high enhancement (range 19-75%, mean 48%). Conclusion: Distinct SI characteristics together with anatomical-topographical features (attachment to the interatrial septum, no infiltration of myocardium and vessels) are diagnostic for cardiac myxomas. Cine-GE and T{sub 2}-TSE sequences are the sequences of choice for detection of myxomas and other atrial masses. T{sub 2}-TSE and contrast-enhanced T{sub 1}-weighted sequences are most useful for mass characterisation and differentiation between myxomas, malignant tumors, and thrombi. (orig.) [Deutsch] Ziel: Evaluierung nativer und kontrastverstaerkter T{sub 1}-gesichteter Spin-Echo-Sequenzen (T{sub 1}-SE), Cine-Gradienten-Echo-Sequenzen (GE) sowie T{sub 2}-gewichteter Turbo-Spin-Echo-Sequenzen (T{sub 2}-TSE) in Diagnostik und Differentialdiagnose kardialer Myxome. Methode: 15 Patienten mit echokardiographischem Verdacht auf ein Vorhofmyxom erhielten eine MRT-Untersuchung des Herzens (0,5 Tesla, EKG-getriggerte T{sub 1}-SE nativ-, T{sub 1}-SE KM-, GE-, T{sub 2

  13. Direct Numerical Simulation of an Adverse Pressure Gradient Turbulent Boundary Layer at the Verge of Separation

    Science.gov (United States)

    Kitsios, Vassili; Atkinson, Callum; Sillero, Juan; Guillem, Borrell; Gungor, Ayse; Jimenéz, Javier; Soria, Julio

    2014-11-01

    We investigate the structure of an adverse pressure gradient (APG) turbulent boundary layer (TBL) at the verge of separation. The intended flow is generated via direct numerical simulation (DNS). The adopted DNS code was previously developed for a zero pressure gradient TBL. Here the farfield boundary condition (BC) is modified to generate the desired APG flow. The input parameters required for the APG BC are initially estimated from a series of Reynolds Averaged Navier-Stokes simulations. The BC is implemented into the DNS code with further refinement of the BC performed. The behaviour of the large scale dynamics is illustrated via the extraction of coherent structures from the DNS using analysis of the velocity gradient tensor and vortex clustering techniques. The authors acknowledge the research funding from the Australian Research Council and European Research Council, and the computational resources provided by NCI and PRACE.

  14. Uma leitura dos poemas inéditos de Vergílio Ferreira

    OpenAIRE

    Godinho, Helder

    1980-01-01

    Revista da Faculdade de Ciências Sociais e Humanas, n.1(1980) Os poemas de Vergílio Ferreira organizam-se em torno de uma Ausência que remete para um Paraíso Perdido, além do Tempo e do Espaço, e de uma Queda, decorrente dessa Ausência. É, com efeito, a Ausência de uma Pessoa Fundamental, Verdade ou Caminho onde o Encontro fosse possível, que provocou a Queda actual no poço de águas mortas e lodosas, onde o Presente é vivido. Porque, cortada por essa Ausência a possibilidade do Encontro...

  15. Upslope-verging back thrusts developed during downslope-directed slumping of mass transport deposits

    Science.gov (United States)

    Alsop, G. I.; Marco, S.; Weinberger, R.; Levi, T.

    2017-07-01

    While much research has recently been focussed on downslope-verging systems of gravity-driven fold and thrust belts within mass transport deposits (MTDs), rather less attention has been paid to back thrusts, which are defined as displaying the opposite vergence to the main transport direction in thrust systems. A fundamental question arises over whether back thrusts in downslope-verging MTDs record actual movement back upslope. In order to address this issue, we have examined exceptional outcrops of Pleistocene fold and thrust systems developed in MTDs around the Dead Sea Basin. Back thrusts can be interpreted in terms of a 'downslope-directed underthrust model', where material moves down slope and is driven into the footwall of the back thrust, resulting in the 'jacking up' of the largely passive hangingwall. Our data support this underthrust model and include the observation that stratigraphic units may be markedly thickened (up to 250%) in the footwall of back thrusts. This thickening is a consequence of pure shear lateral compaction as the 'wedge' of sediment is driven into the footwall to create an underthrust. In addition, back thrusts may be rotated as new back thrusts form in their footwalls, ultimately resulting in overturned thrusts. The observation that steeper back thrusts typically accommodate less displacement than gently-dipping back thrusts suggests that steepening occurred during back thrusting, and is therefore a consequence of 'footwall wedging'. Contrary to some recent interpretations, we demonstrate that back thrusts can develop in gravity-driven systems and cannot therefore be used to distinguish different emplacement mechanisms for MTDs.

  16. 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

  17. 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.)

  18. 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.

  19. 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

  20. Family entrepreneurship in the Czech Republic on the verge of first generation handover

    Directory of Open Access Journals (Sweden)

    Naděžda Petrů

    2017-12-01

    Full Text Available Family is an integral part of society in all cultures and time periods. Its mission is to raise the next generation, which will be able to continue and further develop knowledge and experience of the previous generation. The modern history of family entrepreneurship in Czech Republic restarted back in 1989, i.e., straight after the fall of the communist regime and restoration of the democratic system. People went into business with enthusiasm and the most successful ones among then now stand on the verge of generation handover. The literature review prepared using the desk-research method is mainly based on foreign professional sources – monographic publications, scientific articles published in professional magazines, accessed from Proquest, Web of Science, Ebsco, Scopus and some other databases. The objective of our quantitative research was to evaluate, based on parameter E (Experience, the generational representation of family members in relation to leadership and ownership of businesses. Quantitative research was based on the use of statistical and graphical data processing methods, including SPSS software, applied for the authors’ own empirical investigation based on the international methodology of family company review through the F-PEC scale, the Experience parameter (Astrachan et al., 2002. It was shown that accumulation of business experience in business families is still mainly concentrated on the founding generation of entrepreneurs. In the conclusion of the paper, deduction and generalisation methods have been applied.

  1. Medicinal Formulations of a Kanda Tribal Healer — A Tribe on the Verge of Disappearance in Bangladesh

    OpenAIRE

    Rahmatullah, Mohammed; Ayman, Umma; Akter, Fatema; Sarker, Mridul; Sifa, Rolee; Sarker, Bijoy; Chyti, Humayra Naj; Jahan, Farhana Israt; Chowdhury, Majeedul H; Chowdhury, Soheli A

    2012-01-01

    The Kanda tribe is one of the lesser known small tribes of Bangladesh with an estimated population of about 1700 people (according to them), and on the verge of extinction as a separate entity. To some extent, they have assimilated with the surrounding mainstream Bengali-speaking population, but they still maintain their cultural practices including traditional medicinal practices, for which they have their own tribal healers. Nothing at all has been documented thus far about their traditiona...

  2. Distribution and abundance of bee forage flora across an agricultural landscape – railway embankments vs. road verges

    Directory of Open Access Journals (Sweden)

    Małgorzata Wrzesień

    2016-09-01

    Full Text Available In this study, we evaluated if railway embankments and road verges create refuge habitats for bee flora across agricultural landscape. The survey was conducted in 2009–2012, in the Lublin Province, SE Poland. Data on the bee forage flora were obtained while making floristic charts along 60 transect plots × 300 m, with a total length of 18 000 m, for each type of linear structure. Forage bee flora was compared with respect to species richness, diversity, and evenness indices. The canonical correspondence analysis (CCA was used to characterize relationship between species composition and environmental variables. The bee forage species richness and abundance were significantly greater on railway embankments than on road verges. The composition of species varied considerably; the number of bee forage species common to both habitats was only approximately 38% in entire data set. Most good-value bee forage species were recorded along the embankments of railways with an intermediate traffic volume. Bee forage species diversity benefits from the location of habitat elements (forests or meadows, primarily if the distance is <50 m. The lack of dense patches of valuable bee forage species in the road verges was related to the high density of non-nectariferous graminoids. Our results demonstrate how the value of man-made areas in an agricultural ecosystem can vary with respect to floral resources across the landscape, suggesting that it is inappropriate to generalize about agricultural systems as a whole without first addressing differences among habitats.

  3. Role of male reproductive tract CD52 (mrt-CD52) in reproduction.

    Science.gov (United States)

    Koyama, Koji; Ito, Koichi; Hasegawa, Akiko

    2007-01-01

    Human CD52 antigen is a highly glycosylated molecule with an unusually small core peptide exclusively expressed on lymphocytes and mature sperm. In the male reproductive tract, it is secreted mainly from the epididymis and inserted into the sperm membrane via the glycosyl-phosphatidyl inositol (GPI) anchor during the passage of the spermatozoa through the epididymis. It has recently been found that the male reproductive tract CD52 (mrt-CD52) is a target antigen of human monoclonal antibody (Mab H6-3C4) obtained from an antisperm antibody-mediated infertile woman. The Mab H6-3C4 shows strong sperm-immobilizing activity with complement and specifically recognizes the N-linked carbohydrate epitope of sperm CD52 but not lymphocyte CD52. Lectin binding assays have revealed the presence of both O-linked as well as N-linked carbohydrate moieties in human mrt-CD52. Mouse monoclonal antibody (1 G12) reacting to human mrt-CD52 strongly inhibits penetration of human spermatozoa to the zona denuded hamster oocyte. Mouse CD52 is similar to human CD52 in biological and immunological characteristics. Male and female mice immunized with naturally-occurring mouse mrt-CD52 molecules produce antibodies against the cognate antigen yielding antisera with complement-dependent mouse sperm immobilizing activities.

  4. Biochemical property and immunogenicity of mouse male reproductive tract CD52 (mrt-CD52).

    Science.gov (United States)

    Ito, K; Hasegawa, A; Komori, S; Koyama, K

    2007-08-01

    Male reproductive tract CD52 (mrt-CD52) is known to be a pathogenic antigen for immunological infertility. Although human CD52 has been extensively investigated, the properties of mouse CD52 are not well elucidated. This study was conducted, therefore, to examine the tissue distribution, molecular composition and immunogenicity of mouse mrt-CD52. Immunohistological studies with an antibody to a synthetic peptide showed that mouse CD52 was localized mainly in the cauda epididymis and vas deferens, but not in the testis, liver, kidney or spleen. The molecule was composed of Asn (N)-linked and The/Ser (O)-linked carbohydrates as well as a glycosylphosphatidyl (GPI) anchor portion. Purified mrt-CD52 preparations produced antibodies by subcutaneous and intranasal immunization in both male and female mice. These antisera showed sperm-immobilizing activities with complement to mouse sperm. The research indicated mouse CD52 had similar biochemical and immunological properties to human CD52. This animal experiment is a good model for investigating human mrt-CD52 antibody detected in infertile patients.

  5. 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

  6. Genetics at the verge of extinction: insights from the Iberian lynx.

    Science.gov (United States)

    Casas-Marce, M; Soriano, L; López-Bao, J V; Godoy, J A

    2013-11-01

    Population viability might become compromised by the loss of genetic diversity and the accumulation of inbreeding resulting from population decline and fragmentation. The Iberian lynx (Lynx pardinus) provides a paradigmatic example of a species at the verge of extinction, and because of the well-documented and different demographic histories of the two remaining populations (Doñana and Andújar), it provides the opportunity to evaluate the performance of analytical methods commonly applied to recently declined populations. We used mitochondrial sequences and 36 microsatellite markers to evaluate the current genetic status of the species and to assess the genetic signatures of its past history. Mitochondrial diversity was extremely low with only two haplotypes, alternatively fixed in each population. Both remnant populations have low levels of genetic diversity at microsatellite markers, particularly the population from Doñana, and genetic differentiation between the two populations is high. Bayesian coalescent-based methods suggest an earlier decline starting hundreds of years ago, while heterozygosity excess and M-ratio tests did not provide conclusive and consistent evidence for recent bottlenecks. Also, a model of gene flow received overwhelming support over a model of pure drift. Results that are in conflict with the known recent demography of the species call for caution in the use of these methods, especially when no information on previous demographic history is available. Overall, our results suggest that current genetic patterns in the Iberian lynx are mainly the result of its recent decline and fragmentation and alerts on possible genetic risks for its persistence. Conservation strategies should explicitly consider this threat and incorporate an integrated genetic management of wild, captive and re-introduced populations, including genetic restoration through translocations. © 2013 John Wiley & Sons Ltd.

  7. Mrt, a gene unique to fungi, encodes an oligosaccharide transporter and facilitates rhizosphere competency in Metarhizium robertsii.

    Science.gov (United States)

    Fang, Weiguo; St Leger, Raymond J

    2010-11-01

    The symbiotic associations between rhizospheric fungi and plants have enormous environmental impact. Fungi are crucial to plant health as antagonists of pathogens and herbivores and facilitate the uptake of soil nutrients. However, little is known about the plant products obtained by fungi in exchange or how they are transported through the symbiotic interface. Here, we demonstrate that sucrose and raffinose family oligosaccharides in root exudates are important for rhizosphere competence in the insect pathogen Metarhizium robertsii (formerly known as Metarhizium anisopliae). We identified mutants in the Metarhizium raffinose transporter (Mrt) gene of M. robertsii that grew poorly in root exudate and were greatly reduced in rhizosphere competence on grass roots. Studies on sugar uptake, including competition assays, revealed that MRT was a sucrose and galactoside transporter. Disrupting MRT resulted in greatly reduced or no growth on sucrose and galactosides but did not affect growth on monosaccharides or oligosaccharides composed entirely of glucose subunits. Consistent with this, expression of Mrt is exclusively up-regulated by galactosides and sucrose. Expressing a green fluorescent protein gene under the control of the Mrt promoter confirmed that MRT was expressed by germlings in the vicinity of grass roots but not in surrounding bulk soil. Disrupting Mrt did not reduce virulence to insects, demonstrating that Mrt is exclusively involved in M. robertsii's interactions with plants. To our knowledge, MRT is the first oligosaccharide transporter identified and characterized in a fungus and is unique to filamentous fungi, but homologous genes in Magnaporthe, Ustilago, Aspergillus, Fusarium, Epichloe, and Penicillium species indicate that oligosaccharide transport is of widespread significance.

  8. Ganglioneuromas in childhood: MRI and CT characteristics; Ganglioneurome im Kindesalter: CT- und MRT-Charakteristika

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, A.; Engelbrecht, V.; Moedder, U. [Duesseldorf Univ. (Germany). Inst. fuer Diagnostische Radiologie; Niehues, T. [Duesseldorf Univ. (Germany). Zentrum fuer Kinderheilkunde

    2000-05-01

    Purpose: The aim of this study was to demonstrate the typical appearance of ganglioneuromas in computer-assisted tomography (CT), and magnetic resonance imaging (MRI). Material and methods: Retrospective analysis of diagnostic imaging (9 CT, 6 MRI) in 9 children aged 3 to 15 years with the histological diagnosis of ganglioneuroma. Results: The tomographies showed large (max. 13.4 cm in diameter) round or oval tumors with sharp delineation. The sites of the tumors were the retroperitoneum (5), the mediastinum (3), and the adrenal gland (1). Intraspinal tumor involvement occurred in 4 cases. On comparing CT with MRI, MRI was more accurate in defining the intraspinal involvement. The ganglioneuromas were of hypodense appearance in the native CT scan and showed moderate enhancement upon administration of contrast media. In five patients tumor calcifications with a disseminated sprinkled pattern were seen in CT. In MRI T{sub 1}-weighted scans the tumors were homogeneous and hypointense, after gadolinium application a marked enhancement was evident. In T{sub 2}-weighted scans the tumors were hyperintense. Conclusion: At the time of diagnosis ganglioneuromas are generally large tumors which can be well detected by CT and MRI. Information toward the diagnosis is given by the appearance of the ganglioneuromas in CT and MRI. However, MRI is the modality of choice due to its superiority in documenting intraspinal tumor expansion. (orig.) [German] Ziel: Darstellung typischer Erscheinungsformen von Ganglioneuromen in der Computertomographie (CT) und Magnetresonanztomographie (MRT). Material und Methode: Retrospektive Auswertung der bildgebenden Diagnostik (9 CT, 6 MRT) von 9 Kindern im Alter zwischen 3 und 15 Jahren mit histologisch gesichertem Ganglioneurom. Ergebnisse: Die Schnittbildverfahren wiesen grosse (Durchmesser bis max. 13,4 cm), rundliche bzw. ovale Tumoren mit scharfen Randkonturen nach. Die Tumoren waren retroperitoneal (5), mediastinal (3) bzw. adrenal (1

  9. 3D Simulation of Self-Compacting Concrete Flow Based on MRT-LBM

    Directory of Open Access Journals (Sweden)

    Liu-Chao Qiu

    2018-01-01

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

  10. Formal MRI criteria for the diagnosis of multiple sclerosis; Formale MRT-Kriterien in der Diagnose der Multiplen Sklerose

    Energy Technology Data Exchange (ETDEWEB)

    Harting, I.; Haehnel, S. [Abt. Neuroradiologie, Neurologische Klinik, Universitaetsklinikum Heidelberg (Germany); Meyding-Lamade, U. [Neurologische Klinik, Universitaetsklinikum Heidelberg (Germany)

    2004-06-01

    Multiple scloris (MS) is the most common demyelinating inflammatory disease of the central nervous system, presenting with multifocal, disseminated white matter lesions called plaques. Magnetic resonance imaging (MRI) is very sensitive in detecting white matter abnormalities. By demonstrating the spatial and temporal dissemination in patients presenting with isolated clinical findings suggestive of MS, MRI contributes to estimating the likelihood of the disease. Since MRI is highly sensitive but not specific, it is important to apply formal MRI criteria. This article describes the characteristic MRI changes of MS and the so-called McDonald criteria for an MRI-supported diagnosis of MS. (orig.) [German] Die multiple Sklerose (MS) ist die haeufigste entzuendliche, demyelinisierende Erkrankung des ZNS, die mit multiplen disseminierten Demyelinisierungsherden, sog. Plaques, in der weissen Substanz einhergeht. Die MRT weist mit hoher Sensitivitaet Veraenderungen der weissen Substanz nach. Indem die MRT bereits bei einer klinisch isolierten, MS-verdaechtigen Erstsymptomatik die raeumliche und zeitliche Disseminierung der Erkrankung belegt, traegt die Methode dazu bei, die Erkrankungswahrscheinlichkeit abzuschaetzen. Da die MRT zwar hoch sensitiv, aber nicht spezifisch ist, ist die Anwendung formaler MRT-Kriterien fuer die Diagnose der MS sehr wichtig. Dieser Artikel beschreibt die charakteristischen MRT-Veraenderungen der MS und die sog. McDonald-Kriterien einer MRT-gestuetzten Diagnose der MS. (orig.)

  11. The MRT-1 nuclease is required for DNA crosslink repair and telomerase activity in vivo in Caenorhabditis elegans.

    Science.gov (United States)

    Meier, Bettina; Barber, Louise J; Liu, Yan; Shtessel, Ludmila; Boulton, Simon J; Gartner, Anton; Ahmed, Shawn

    2009-11-18

    The telomerase reverse transcriptase adds de novo DNA repeats to chromosome termini. Here we define Caenorhabditis elegans MRT-1 as a novel factor required for telomerase-mediated telomere replication and the DNA-damage response. MRT-1 is composed of an N-terminal domain homologous to the second OB-fold of POT1 telomere-binding proteins and a C-terminal SNM1 family nuclease domain, which confer single-strand DNA-binding and processive 3'-to-5' exonuclease activity, respectively. Furthermore, telomerase activity in vivo depends on a functional MRT-1 OB-fold. We show that MRT-1 acts in the same telomere replication pathway as telomerase and the 9-1-1 DNA-damage response complex. MRT-1 is dispensable for DNA double-strand break repair, but functions with the 9-1-1 complex to promote DNA interstrand cross-link (ICL) repair. Our data reveal MRT-1 as a dual-domain protein required for telomerase function and ICL repair, which raises the possibility that telomeres and ICL lesions may share a common feature that plays a critical role in de novo telomere repeat addition.

  12. The GEANT4 toolkit for microdosimetry calculations: application to microbeam radiation therapy (MRT).

    Science.gov (United States)

    Spiga, J; Siegbahn, E A; Bräuer-Krisch, E; Randaccio, P; Bravin, A

    2007-11-01

    Theoretical dose distributions for microbeam radiation therapy (MRT) are computed in this paper using the GEANT4 Monte Carlo (MC) simulation toolkit. MRT is an innovative experimental radiotherapy technique carried out using an array of parallel microbeams of synchrotron-wiggler-generated x rays. Although the biological mechanisms underlying the effects of microbeams are still largely unknown, the effectiveness of MRT can be traced back to the natural ability of normal tissues to rapidly repair small damages to the vasculature, and on the lack of a similar healing process in tumoral tissues. Contrary to conventional therapy, in which each beam is at least several millimeters wide, the narrowness of the microbeams allows a rapid regeneration of the blood vessels along the beams' trajectories. For this reason the calculation of the "valley" dose is of crucial importance and the correct use of MC codes for such purposes must be understood. GEANT4 offers, in addition to the standard libraries, a specialized package specifically designed to deal with electromagnetic interactions of particles with matter for energies down to 250 eV. This package implements two different approaches for electron and photon transport, one based on evaluated data libraries, the other adopting analytical models. These features are exploited to cross-check theoretical computations for MRT. The lateral and depth dose profiles are studied for the irradiation of a 20 cm diameter, 20 cm long cylindrical phantom, with cylindrical sources of different size and energy. Microbeam arrays are simulated with the aid of superposition algorithms, and the ratios of peak-to-valley doses are computed for typical cases used in preclinical assays. Dose profiles obtained using the GEANT4 evaluated data libraries and analytical models are compared with simulation results previously obtained using the PENELOPE code. The results show that dose profiles computed with GEANT4's analytical model are almost

  13. 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

  14. Cardiac MRI in suspected myocarditis; MRT des Herzens bei Verdacht auf Myokarditis

    Energy Technology Data Exchange (ETDEWEB)

    Rieker, O.; Oberholzer, K.; Kreitner, K.F.; Thelen, M. [Klinik fuer Radiologie der Johannes Gutenberg-Univ. Mainz (Germany); Mohrs, O. [Klinik fuer Radiologie der Johannes Gutenberg-Univ. Mainz (Germany); Cardioangiologisches Centrum Bethanien, Frankfurt (Germany)

    2002-12-01

    Purpose: To evaluate the potential of ECG-gated breath-hold MRI in diagnosing acute myocardidits. Material and methods: Cardiac MRI was performed on 21 consecutive patients with suspected myocarditis. ECG-gated breath-hold T2-weighted images with fat suppression were acquired in 3 standard views. T1-weighted imaging (FLASH) was performed 10 min after IV administration of Gd-DTPA. Laboratory data included creatine kinase, troponin T and serological tests, ECG findings and echocardiography. Imaging findings were retrospectively compared to the discharge diagnoses. Signal alterations were semiquantitatively classified. Results: Acute myocarditis was diagnosed in 9 patients and cardiac sarcoidosis in 2 patients. Late enhancement was observed in 4 patients with acute myocarditis and in both patients with cardiac sarcoidosis. Semiquantitative evaluation revealed 9 true positive, 9 true negative, 1 false positive and 2 false negative results. Conclusion: Cardiac MRI has the potential to detect acute myocarditis and to diagnose cardiac sarcoidosis. Late enhancement of Gd-DTPA can be found in both viral myocarditis and cardiac sarcoidosis. (orig.) [German] Ziel: Beurteilung des diagnostischen Potenzials der MRT des Herzens bei Verdacht auf akute Myokarditis. Material und Methoden: 21 konsekutive Patienten mit Verdacht auf Myokarditis wurden mit einem standardisierten Protokoll untersucht. Zunaechst wurden T{sub 2}-gewichtete, EKG-getriggerte fettsupprimierte Sequenzen in den 3 Standardebenen angefertigt. 10 Minuten nach intravenoeser Injektion von GD-DTPA wurden T{sub 1}-gewichtete TurboFLASH-Sequenzen angefertigt. Von allen Patienten wurden EKG, Echokardiographie und die Laborbefunde einschliesslich Creatinin-Kinase, Troponin T und der Infektionsserologie protokolliert. Das Ausmass der Signalveraenderungen im MRT wurde semiquantitativ klassifiziert. Die Ergebnisse der MRT wurden retrospektiv mit den Entlassungsdiagnosen korreliert. Ergebnisse: Bei 9 Patienten lag nach

  15. 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

  16. [Studies of the origin of malignant rhabdoid tumor(MRT)--experimental researches on the MRT evolving in nude mice inoculated with violently variable HeLa cells].

    Science.gov (United States)

    Zhang, D L; Huang, G S; Li, L J; He, X Y; Xia, G T; Gao, B X; Bai, X H; Liu, S G

    2000-01-01

    Under the prerequisite that the incidence of cancer or tumor in negatively-controlled nude mice inoculated subcutaneously with feline or canine kidney cell cultures purified in vitro at passage 3 or higher (the modal chromosome number of FKC on passage 3 was 38 of diploid at the rate of 80%) was 0%(0/22) and 0%(0/10) respectively, and the incidence of progressively negative growing tumor in controlled nude mice inoculated subcutaneously with repeatedly-frozen- and thawed-HeLa cell cultures of X strain was 20%(1/5), the negative growing malignant tumor (MT) was found in half of the nude mice inoculated subcutaneously with HeLa cell cultures of H strain(with modal chromosome number of 78 +/- 2 of sub-tetraploid at the rate of 40%), the progressively-growing malignant tumor was found in all the other 40 nude mice inoculated subcutaneously with HeLa cell cultures of other strains, with the incidence of MT in nude mice with KB strain (with modal chromosome number of 60 +/- 3 of hyperdiploid at the rate of 72%-76%) 10/10, the incidence of poorly-differentiated MT originated from epithelia in nude mice with X strain (with modal chromosomal number of 62 +/- 3 of hyperdiploid at the rate of 69%) 25/25, and the incidence of MRT in nude mice with in vitro cultured tumor cell NM20/X strain (with modal chromosome number of 68 +/- 3 of both hyperdiploid and subtetraploid at the rate of 52%) 5/5. After being continuously cultivated for 20 passages in vitro, HeLa cell of X strain was subcutaneously inoculated into nude mice and cultivated for 1 passage in vivo within 15 days, and then the developed growing MT was collected as HeLa cell of NM20/X strain on passage 0 and continuously cultivated for 11 passages to prepare for transplanting into nude mice again. Therefore, the highly variable strain of HeLa cells can be successfully selected by alternate cultivation in vitro and in vivo. Occasionally in another experiment, the progressively-growing MRT was found in all the 4 nude mice

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-12-15

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

  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. Desde la vergüenza y la humillación hacia una pedagogía del reconocimiento y la dignidad humana

    Directory of Open Access Journals (Sweden)

    Stephan Marks

    2012-03-01

    Full Text Available La vergüenza es un sentimiento universal, todos los seres humanos la conocen, − aunque tiene manifestaciones diferentes dependiendo de la cultura a la que se pertenece y según sí se es hombre o mujer. La vergüenza es un sentimiento “casero“ y torturador, que difícilmente se puede describir con palabras. Está íntimamente ligada a reacciones corporales como el sonrojo. Cuando nos avergonzamos nos sentimos como atropellados. Perdemos, por lo menos temporalmente, la serenidad y el autocontrol.

  20. 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

  1. 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

  2. [Evaluation of the Marburg Spelling Training (MRT) in 2nd- and 3rd-grade students with spelling difficulties].

    Science.gov (United States)

    Barkmann, Claus; Kuhlmann, Ester; Rosenboom, Lea; Wessolowski, Nino; Schulte-Markwort, Michael

    2012-05-01

    Children with severe dyslexia are substantially impaired because reading and writing are key competencies necessary for a successful academic and occupational career. In this evaluation study, a cohort of 2nd- and 3rd-grade students from a variety of Hamburg primary schools was trained with the Marburger Rechtschreibtraining (MRT) by supervised university graduates. The research questions focused on the feasibility of the MRT as a within-school training, the improvement of spelling and reading skills of the participants, subjective assessments of success, as well as potential predictors. Besides established performance tests, we also considered the subjective appraisals of parents, teachers, and coaches. The results demonstrate that standardized spelling training methods like the MRT can be consistently used during morning hours at schools. Within a year of starting MRT exercises, mean effect sizes in writing and reading were observed in performance tests using test norms. However, parent, teacher, and coach reports failed to replicate these improvements. Changes in writing performance were mainly associated with school class level; improvements in reading ability were dependent on initial writing performance. The results provide starting points for optimizing current training practices in elementary schools and for posing questions regarding the effectiveness of the MRT, as well as for training programs in general.

  3. New developments in MRI of the liver; Neuere Entwicklungen der Leber-MRT

    Energy Technology Data Exchange (ETDEWEB)

    Bastati-Huber, N.; Prosch, H.; Baroud, S.; Magnaldi, S.; Ba-Ssalamah, A. [AKH, Medizinische Universitaet Wien, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria); Schima, W. [Krankenhaus Goettlicher Heiland, Wien, Abteilung fuer Radiologie und Bildgebende Diagnostik, Wien (Austria)

    2011-08-15

    Radiology has gained an exceptional position in medicine because a correct diagnosis is the most crucial issue in determining an accurate and personalized therapeutic strategy. This has a direct influence not only on the individual patient but also on the socio-economic aspects of healthcare services in terms of shortening the time interval to establish a diagnosis and to avoid risk-associated invasive diagnostic methods or long-term, cost-intensive follow-up. Magnetic resonance imaging (MRI) is an excellent example of this which due to continuous technological developments and emerging techniques allows a non-invasive diagnosis of the different hepatic diseases. In this article, we illustrate the direct correlation between the recent technical advances in MRI, such as 3.0 T, diffusion-weighted imaging, perfusion imaging, spectroscopy, texture analysis and MR elastography and obtaining a confident non-invasive diagnosis of focal and diffuse liver diseases. (orig.) [German] Das Fach Radiologie hat in der Medizin eine Sonderstellung erlangt. Eine exakte Diagnose ist entscheidend, um rasch und effizient behandeln zu koennen. Dies wirkt sich direkt auf den einzelnen Patienten aus, was mit einer Verkuerzung der Zeit bis zur Diagnosestellung, dem Vermeiden unnoetiger invasiver Methoden oder teuren zeitaufwendigen Verlaufskontrollen einhergeht. Die MRT stellt aufgrund ihrer kontinuierlichen Entwicklungen der letzten Jahre ein Musterbeispiel dar, v. a. bei der Diagnostik der verschiedenen Lebererkrankungen. In diesem Artikel erlaeutern wir den direkten Zusammenhang zwischen neueren technischen Entwicklungen im Bereich der MRT wie 3,0 T, diffusionsgewichteten Sequenzen, Perfusions-MRT, Spektroskopie, Texturanalyse sowie MR-Elastographie und dem Stellen einer sicheren, nichtinvasiven Diagnose der fokalen und diffusen Leberveraenderungen. (orig.)

  4. 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

  5. [MRT assessment of metabolic and thrombolytic therapy effects on postinfarction left ventricular remodeling].

    Science.gov (United States)

    Tarasov, N I; Kokov, A N; Barbarash, L S

    2006-01-01

    To examine effects of trimetasidine on morphofunctional indices of the left ventricle (LV) in myocardial infarction (MI) patients on combined treatment. Seventy five patients with primary macrofocal MI were randomized into 2 groups. Patients of group 1 (n = 38) received a combination of bisoprolol (beta-blocker) with enalapril (ACE inhibitor) in individual doses under control of blood pressure and blood creatinine level. Group 2 (n = 37) patients received the same combination of drugs and, in addition, trimetasidine in a dose 70 mg/day from postmyocardial day 7-10 for 6 months. Two subgroups from the groups were given systemic thrombolytic therapy (STLT) with streptokinase. MRT and cine-MRT of the heart were made for measurement of LV morphofunctional parameters. Low-field MRT of the heart in MI patients treated with adjuvant STLT (1500000 U within 6 hours after MI onset) and trimetasidine (preductal MB) in a dose 70 mg/day from the disease day 7-10 registered a significant inhibition of pathological LV postinfarction remodeling: a decrease of body surface indexed LV end diastolic volume by 10.3%, systolic volume--by 15.4%, LV myocardial tension--by 14.0%, sphericity index--by 7.1%; an increase in the index of relative wall thickness by 5.3%, cardiac index--by 9.2% compared to the group treated without trimetasidine. 6-month therapy with trimetasidine of MI patients leads to a significant regress of morphofunctional changes accompanying LV remodeling. Pathological LV postinfarction remodeling inhibits significantly in MI patients combined treatment of whom included STLT (streptokinase in a dose 1500,000 U within 6 hours after acute MI onset and trimetasidine in a dose 70 mg/day on postmyocardial infarction day 7-10).

  6. 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

  7. Turbulent jet computations based on MRT and Cascaded Lattice Boltzmann models

    OpenAIRE

    Geller, S; Uphoff, S.; Krafczyk, M.

    2012-01-01

    In this contribution a numerical study of a turbulent jet flow is presented. The simulation results of two different variants of the Lattice Boltzmann method (LBM) are compared. The first is the well-established D3Q19 MRT model extended by a Smagorinsky Large Eddy Simulation (LES) model. The second is the D3Q27 Factorized Cascaded Lattice Boltzmann (FCLB) model without any additional explicit turbulence model. For this model no studies of turbulent flow with high resolution on nonuniform grid...

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

    Science.gov (United States)

    Bartzsch, Stefan; Lerch, Michael; Petasecca, Marco; Bräuer-Krisch, Elke; Oelfke, Uwe

    2014-04-01

    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. 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 by Martínez-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. 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 the field center, increased

  9. La reputation scientifique contestee des freres Bogdanov

    CERN Multimedia

    Morin, H

    2002-01-01

    "Les celebres jumeaux sont revenus a la television apres avoir obtenu des theses en mathematiques et physique theorique. Depuis, ils sont la cible de virulentes critiques portant sur la qualite reelle de leurs travaux" (1 page).

  10. The N-linked carbohydrate moiety of male reproductive tract CD52 (mrt-CD52) interferes with the complement system via binding to C1q.

    Science.gov (United States)

    Hardiyanto, Lutfi; Hasegawa, Akiko; Komori, Shinji

    2012-06-01

    Antisperm antibody detected in infertile female patients' sera has been shown to correlate with reduced fertility. The antibody showed strong complement-dependent cytotoxicity as determined by the sperm immobilization test (SIT). CD52 is a human glycosylphosphatidylinositol (GPI)-anchored antigen present in lymphocytes and male reproductive tracts (mrt), including mature sperm and seminal plasma. Recently, purified mrt-CD52 from human seminal plasma has been reported to interfere with the classical complement pathway, but not lectin binding or alternative pathways of the complement system. The purpose of this study is to determine which stage of the classical pathway mrt-CD52 regulates. mrt-CD52 was purified from human seminal plasma or intact sperm membrane. Immunoprecipitation assay was performed with the reaction of mrt-CD52, human complement and mAb H6-3C4. Immunoprecipitate was formed by the carbohydrate moiety of mrt-CD52, but not by the GPI-anchor peptide. The C1q molecule (29 kDa) was detected in the immunoprecipitates by Western blotting analysis probed with anti C1q antibody, indicating that the carbohydrate moiety of mrt-CD52 binds to C1q. Also, the complement-dependent SIT revealed that purified CD52 inhibited sperm immobilization activity by antisperm antibody. These results suggest that mrt-CD52 protects sperm function from complement attack if antisperm antibody is generated in the female reproductive tracts. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  11. Combined PET-MRI of the abdomen; Kombinierte PET-MRT des Abdomens

    Energy Technology Data Exchange (ETDEWEB)

    Vag, Tibor; Eiber, M.; Schwaiger, M. [Technische Universitaet Muenchen, Klinik fuer Nuklearmedizin, Klinikum Rechts der Isar, Muenchen (Germany)

    2015-12-15

    The first fully integrated combined positron emission tomography-magnetic resonance imaging (PET-MRI) scanners have been clinically available since 2010. Large prospective studies regarding indications and diagnostic accuracy of this new modality are not yet available; however, preliminary studies have shown a higher diagnostic accuracy and confidence compared to PET-computed tomography (PET-CT) in regions where MRI is known to be superior to CT, such as the liver. The benefit of MRI in accurate lesion characterization and the additional value of diffusion-weighted imaging (DWI) as a complementary functional modality by means of the apparent diffusion coefficient (ADC) is apparent in entities with low tracer uptake (e. g. due to small size) and a decreased or absent accumulation pattern on PET. (orig.) [German] Seit 2010 sind die ersten voll integrierten Positronenemissionstomographie(PET)-MR-Scanner im klinischen Gebrauch. Obwohl es derzeit noch an empirischen Daten im Sinne groesserer und prospektiver Studien fehlt, implizieren erste Studien einen diagnostischen Mehrwert gegenueber der PET-CT in Regionen, in denen die MRT bekanntermassen der CT ueberlegen ist. Diese ist in der besseren morphologischen Charakterisierung begruendet, die insbesondere bei Laesionen mit geringer Tracerspeicherung (z. B. aufgrund der geringen Groesse) oder unbekanntem Speicherverhalten in der PET ausschlaggebend ist. Zudem steht der MRT eine komplementaere funktionelle Modalitaet in Form der Diffusionsbildgebung zur Verfuegung, die ueber die Berechnung des Apparent-diffusion-coefficient(ADC)-Werts eine weitere Einschaetzung des Gewebes geben kann. (orig.)

  12. MR imaging in benign symmetric lipomatosis; MRT bei benigner symmetrischer Lipomatose

    Energy Technology Data Exchange (ETDEWEB)

    Gufler, H. [Abt. Roentgendiagnostik, Radiologische Klinik, Freiburg Univ. (Germany); Buitrago-Tellez, C.H. [Abt. Roentgendiagnostik, Radiologische Klinik, Freiburg Univ. (Germany)

    1994-12-31

    Benign symmetric lipomatosis is a rare disease of unknown origin characterized by massive symmetric fat deposits predominantly on the neck, shoulders, arms, and upper part of the trunc. We present three cases of benigne symmetric lipomatosis, who underwent magnetic resonance imaging before surgical removal of the fatty masses was performed. Magnetic resonance imaging is useful in the tissue characterization and evaluation of the extension of these confluent lipomas. MRI showed excellent natural contrast between the hyperintense fatty masses and the hypointense surrounding structures. Sagittal and coronal scans provided particular useful additional anatomic information. (orig.) [Deutsch] Die benigne symmetrische Lipomatose (Madelung-Launois-Bensaude Syndrom) ist eine sehr seltene Erkrankung noch nicht geklaerter Genese. Es werden klinischer Verlauf und MRT Befunde von drei Patienten mit benigner symmetrischer Lipomatose vorgestellt. Charakteristisch fuer diese Erkrankung ist in der MRT die hohe Signalintensitaet in der T1 Gewichtung und die intermediaere Signalgebung in der T2 Gewichtung. Das Fehlen einer umhuellenden Kapsel unterscheidet diese Fettgewebsvermehrung von einem Lipom und ist neben der Lokalisation das hilfreichste Kriterium zur Diagnose: Die unscharfe Begrenzung zu den umgebenden Organen und Strukturen wie Trachea, Nervenplexus, Gefaessen und mediastinalen Organen ohne Nachweis einer Infiltration. Sagittale und coronare Schnittbilder bringen einen zusaetzlichen Informationsgewinn, um Lagebeziehungen eindeutig darzustellen. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-02-15

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

  14. MRI diagnosis of right ventricular dysplasia; MRT-Diagnostik der rechtsventrikulaeren Dysplasie

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, T.; Pauleit, D.; Hofer, U.; Schild, H. [Radiologische Universitaetsklinik Bonn (Germany); Lewalter, T.; Luederitz, B. [Medizinische Universitaetsklinik und Poliklinik Bonn (Germany); Bierhoff, E.; Pakos, E. [Bonn Univ. (Germany). Pathologisches Inst.; Smekal, A. v. [Universitaetsspital Zuerich (Switzerland). Inst. fuer Diagnostische Radiologie

    1998-12-01

    Purpose: Right ventricular dysplasia (RVD) represents an important cause of sudden death and ventricular arrhythmias in young patients. The aim of this study was to describe diagnostic criteria and the MR-tomographic aspects of the disease. Results: Right myocardial fatty infiltration was detected by MRI in 11 of 16 patients (69%) with RVD. Dilatation of the right ventricle was seen in 5 patients, dilatation of the right outflow tract in one patient, and localised right ventricular aneurysm in two patients with RVD. Conclusions: MRI is able to demonstrate fatty replacement of right ventricular myocardium in most cases and plays an important role in the diagnosis of RVD. (orig./AJ) [Deutsch] Ziel: Die rechtsventrikulaere Dysplasie (RVD) stellt eine in den letzten Jahren zunehmend beachtete Ursache ventrikulaerer Tachyarrhythmien und des ploetzlichen Herztodes bei juengeren Patienten dar. Ziel dieser Studie ist es, diagnostische Kriterien und MR-tomographische Aspekte der RVD darzustellen sowie die Wertigkeit der MRT im Nachweis der RVD-typischen lipomatoesen Degeneration des rechtsventrikulaeren Myokards zu evaluieren. Ergebnisse: Lipomatoeses rechtsventrikulaeres Ersatzgewebe konnte MR-tomographisch bei 11/16 Patienten (69%) mit RVD nachgewiesen werden. Des weiteren zeigte sich bei den Patienten mit gesicherter RVD eine RV-Dilatation in 5 Faellen, eine RVAT-Dilatation in einem Fall sowie aneurysmatische rechtsventrikulaere Wandaussackungen in zwei Faellen. Schlussfolgerungen: Die MRT kann das pathomorphologische Substrat der RVD, den fibro-lipomatoesen Ersatz des rechtsventrikulaeren Myokards, in einem Grossteil der Faelle darstellen und liefert damit einen entscheidenden Beitrag zur Diagnostik der RVD. (orig./AJ)

  15. A hydrodynamically-consistent MRT lattice Boltzmann model on a 2D rectangular grid

    Science.gov (United States)

    Peng, Cheng; Min, Haoda; Guo, Zhaoli; Wang, Lian-Ping

    2016-12-01

    A multiple-relaxation time (MRT) lattice Boltzmann (LB) model on a D2Q9 rectangular grid is designed theoretically and validated numerically in the present work. By introducing stress components into the equilibrium moments, this MRT-LB model restores the isotropy of diffusive momentum transport at the macroscopic level (or in the continuum limit), leading to moment equations that are fully consistent with the Navier-Stokes equations. The model is derived by an inverse design process which is described in detail. Except one moment associated with the energy square, all other eight equilibrium moments can be theoretically and uniquely determined. The model is then carefully validated using both the two-dimensional decaying Taylor-Green vortex flow and lid-driven cavity flow, with different grid aspect ratios. The corresponding results from an earlier model (Bouzidi et al. (2001) [28]) are also presented for comparison. The results of Bouzidi et al.'s model show problems associated with anisotropy of viscosity coefficients, while the present model exhibits full isotropy and is accurate and stable.

  16. Determination of dosimetrical quantities used in microbeam radiation therapy (MRT) with Monte Carlo simulations.

    Science.gov (United States)

    Siegbahn, E A; Stepanek, J; Bräuer-Krisch, E; Bravin, A

    2006-09-01

    Microbeam radiation therapy (MRT) is being performed by using an array of narrow rectangular x-ray beams (typical beam sizes 25 microm X 1 cm), positioned close to each other (typically 200 microm separation), to irradiate a target tissue. The ratio of peak-to-valley doses (PVDR's) in the composite dose distribution has been found to be strongly correlated with the normal tissue tolerance and the therapeutic effect of MRT. In this work a Monte Carlo (MC) study of the depth- and lateral-dose profiles in water for single x-ray microbeams of different shapes and energies has been performed with the MC code PENELOPE. The contributions to the dose deposition from different interaction types have been determined at different distances from the center of the microbeam. The dependence of the peak dose, in a water phantom, on the microbeam field size used in the preclinical trials, has been demonstrated. Composite dose distributions for an array of microbeams were obtained using superposition algorithms and PVDR's were determined and compared with literature results obtained with other Monte Carlo codes. The dependence of the PVDR's on microbeam width, x-ray energy used, and on the separation between adjacent microbeams has been studied in detail.

  17. 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

  18. 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.)

  19. Medicinal formulations of a Kanda tribal healer--a tribe on the verge of disappearance in Bangladesh.

    Science.gov (United States)

    Rahmatullah, Mohammed; Ayman, Umma; Akter, Fatema; Sarker, Mridul; Sifa, Rolee; Sarker, Bijoy; Chyti, Humayra Naj; Jahan, Farhana Israt; Chowdhury, Majeedul H; Chowdhury, Soheli A

    2013-01-01

    The Kanda tribe is one of the lesser known small tribes of Bangladesh with an estimated population of about 1700 people (according to them), and on the verge of extinction as a separate entity. To some extent, they have assimilated with the surrounding mainstream Bengali-speaking population, but they still maintain their cultural practices including traditional medicinal practices, for which they have their own tribal healers. Nothing at all has been documented thus far about their traditional medicinal practices and formulations, which are on the verge of disappearance. The Kanda tribe can be found only in scattered tea gardens of Sreemangal in Sylhet district of Bangladesh; dispersion of the tribe into small separated communities is also contributing to the fast losing of traditional medicinal practices. The objective of the present study was to conduct an ethnomedicinal survey among the traditional healers of the Kanda tribe (in fact, only one such healer was found after extensive searches). Information was collected from the healer with the help of a semi-structured questionnaire and the guided field-walk method. A total of 24 formulations were obtained from the healer containing 34 plants including two plants, which could not be identified. Besides medicinal plants, the Kanda healer also used the body hairs of the Asiatic black bear (Ursus thibetanus) and bats (Pteropus giganteus giganteus) in one of his formulation for treatment of fever with shivering. The ailments treated by the Kanda healer were fairly common ailments like cuts and wounds, skin diseases, helminthiasis, fever, respiratory problems (coughs, asthma), gastrointestinal disorders (stomach pain, constipation, diarrhea), burning sensations during urination, various types of pain (headache, body ache, toothache, ear ache), conjunctivitis, poisonous snake, insect or reptile bites, jaundice, and bone fractures. A number of important drugs in allopathic medicine like quinine, artemisinin, and morphine

  20. Importance of whole body MRI for staging of colorectal cancer; Bedeutung der Ganzkoerper-MRT beim Staging des kolorektalen Karzinoms

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, G. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer klinische Radiologie, Muenchen (Germany)

    2012-06-15

    Staging and follow-up of colorectal cancer are usually performed with multimodal imaging strategies. These can be time-intensive and potentially lead to examiner-dependent bias. Alternatively, whole body magnetic resonance imaging (WB-MRI) provides oncologic imaging with a systemic approach. Ultrasound, multislice computed tomography (MSCT), dedicated MRI and positron emission tomography/CT (PET/CT). High-resolution WB-MRI with focused examination of various organs, such as the pelvis and abdomen, lungs, brain and skeletal system, using different sequence and contrast techniques. Detection of colorectal tumor recurrence with WB-MRI provides 83% accuracy (lymph node metastases 80%, organ metastases 86%). Potential cost reduction through decreased examination time and personnel costs. Whole body MRI is a radiation-free alternative to standard sequential algorithms of staging and follow-up of colorectal cancer. (orig.) [German] Staging/Follow-up beim kolorektalen Karzinom wird normalerweise mit multimodalen Bildgebungsverfahren durchgefuehrt. Diese koennen jedoch zeitintensiv sein und bergen die Gefahr einer untersucherabhaengigen Befundvarianz. Alternativ bietet die Ganzkoerper-MRT eine onkologische Bildgebung mit einem systemischen Ansatz. Sonographie, dedizierte MRT, Mehrzeilencomputertomographie (MSCT) oder Positronenemissionstomographie/CT (PET/CT). Hochaufloesende Ganzkoerper-MRT mit fokussierten Untersuchungen einzelner Organe, z. B. Becken und Bauchorgane, Lunge, Gehirn oder Skelettsystem mit unterschiedlichen Sequenztechniken und Kontrastierungen. Kolorektale Rezidiverkennung mit der Ganzkoerper-MRT: 83% Genauigkeit (Lymphknotenmetastasen 80%, Fernmetastasen 86%). Potenzielle Kostenreduktion durch Verringerung der Untersuchungszeiten und Personalkosten. Strahlungsfreie Alternative zu klassischen Stufenalgorithmen beim Staging/Follow-up des kolorektalen Karzinoms. (orig.)

  1. Virtual screening-based discovery and mechanistic characterization of the acylthiourea MRT-10 family as smoothened antagonists.

    Science.gov (United States)

    Manetti, Fabrizio; Faure, Helene; Roudaut, Hermine; Gorojankina, Tatiana; Traiffort, Elisabeth; Schoenfelder, Angele; Mann, Andre; Solinas, Antonio; Taddei, Maurizio; Ruat, Martial

    2010-10-01

    The seven-transmembrane receptor Smoothened (Smo) is the major component involved in signal transduction of the Hedgehog (Hh) morphogens. Smo inhibitors represent a promising alternative for the treatment of several types of cancers linked to abnormal Hh signaling. Here, on the basis of experimental data, we generated and validated a pharmacophoric model for Smo inhibitors constituted by three hydrogen bond acceptor groups and three hydrophobic regions. We used this model for the virtual screening of a library of commercially available compounds. Visual and structural criteria allowed the selection of 20 top scoring ligands, and an acylthiourea, N-(3-benzamidophenylcarbamothioyl)-3,4,5-trimethoxybenzamide (MRT-10), was identified and characterized as a Smo antagonist. The corresponding acylurea, N-(3-benzamidophenylcarbamoyl)-3,4,5-trimethoxybenzamide (MRT-14), was synthesized and shown to display, in various Hh assays, an inhibitory potency comparable to or greater than that of reference Smo antagonists cyclopamine and N-((3S,5S)-1-(benzo[d][1,3]dioxol-5-ylmethyl)-5-(piperazine-1-carbonyl)pyrrolidin-3-yl)-N-(3-methoxybenzyl)-3,3-dimethylbutanamide (Cur61414). Focused virtual screening of the same library further identified five additional related antagonists. MRT-10 and MRT-14 constitute the first members of novel families of Smo antagonists. The described virtual screening approach is aimed at identifying novel modulators of Smo and of other G-protein coupled receptors.

  2. Den komplexa väven Att organisera för barns övergångar till och från förskoleklass

    Directory of Open Access Journals (Sweden)

    Helena Ackesjö

    2015-09-01

    Full Text Available This study focuses on how children's transitions to and from preschool classes are organized in different schools. Principal’s arguments for this organization were sought via a web-based survey and analyzed using the frame factor theory in addition to theories of practical sense and the concept of continuity. The results show that children tend to make more transitions between social communities the younger they are. The distribution of the principal’s answers show that the majority of them, because of external conditions, split the preschool groups to new classes in the transition to preschool class. However, the same movements are not indicated in the transition to first grade. The results show how the work of organizing chidren’s transitions represent a complex web of external actual conditions as the number of children and the recruitment area of the school, the internal logics and ideas about what is best for children and best for continued learning as well as the school's own traditions of working with transitions. Föreliggande studie fokuserar på hur barns övergångar till och från förskoleklass organiseras på olika skolor. Via en webbaserad enkät söks skolledares argument för denna organisering. I analysen nyttjas ett ramfaktorteoretiskt tänkande som kompletteras med teorier om praktiskt förnuft samt kontinuitetsbegreppet. Resultaten visar att barn tenderar att göra fler övergångar mellan barngrupper och sociala gemenskaper ju yngre de är. Fördelningen av skolledarnas svar visar att majoriteten, på grund av yttre villkor, delar förskolegrupperna till nya klasser i övergången till förskoleklass. Däremot indikeras inte samma rörlighet i övergången till årskurs 1. Resultaten visar hur arbetet med att organisera övergångarna utgör en komplex väv av yttre faktiska villkor som barnantal och upptagningsområdets storlek, av inre logiker och föreställningar om vad som är det bästa för barnen och det b

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-04-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-03-01

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

  5. 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.

  6. Structural evidence for the allochthonous nature of the Bulbul terrane in southern Ethiopia: A west-verging thrust nappe

    Science.gov (United States)

    Yihunie, Tadesse; Tesfaye, Melaku

    2002-02-01

    The Neoproterozoic basement of southern Ethiopia links the low-grade Pan-African province of the Arabian-Nubian Shield to the high-grade Mozambique Belt to the south. In this intervening area, a northward terminating low-grade metavolcano-sedimentary and mafic-ultramafic sequence of the Bulbul terrane gently overlies moderately to steeply dipping granitic migmatites of the Alghe gneissic terrane. The contact between the two terranes is a right lateral thrust. In the Bulbul terrane, rocks are part of an overturned sequence with a gently east-dipping composite D1/D2 foliation containing downdip and NE-plunging stretching lineations and westerly verging intrafolial folds. These structures are interpreted to have been developed during westward thrusting. The Bulbul sequence was therefore detached and tectonically transported to the west as a thrust nappe of which the lower inverted limb is still preserved. Structural evidence suggest yet another smaller nappe sequence (terrane) is present in southern Ethiopia and further suggest that Neoproterozoic obducted crust of the Arabian-Nubian Shield in eastern Ethiopia may be located beneath Phanerozoic cover.

  7. How maize monoculture and increasing winter rainfall have brought the hibernating European hamster to the verge of extinction.

    Science.gov (United States)

    Tissier, Mathilde L; Handrich, Yves; Robin, Jean-Patrice; Weitten, Mathieu; Pevet, Paul; Kourkgy, Charlotte; Habold, Caroline

    2016-05-06

    Over the last decades, climate change and agricultural intensification have been identified as two major phenomena negatively affecting biodiversity. However, little is known about their effects on the life-history traits of hibernating species living in agro-ecosystems. The European hamster (Cricetus cricetus), once a common rodent on agricultural land, is now on the verge of extinction in France. Despite the implemented measures for its protection, populations are still in sharp decline but the reasons for it remain unclear. To investigate how environmental change has affected this hibernating rodent, we used a data set based on 1468 recordings of hamster body mass at emergence from hibernation from 1937 to 2014. We reveal the adverse effects of increasing winter rainfall and maize monoculture intensification on the body mass of wild hamsters. Given the links that exist between body mass, reproductive success and population dynamics in mammals, these results are of particular importance to understand the decline of this species. In view of the rates of maize monoculture intensification and the predicted increase in winter rainfall, it is of the utmost importance to improve land management in Western Europe to avoid the extinction of this species.

  8. How maize monoculture and increasing winter rainfall have brought the hibernating European hamster to the verge of extinction

    Science.gov (United States)

    Tissier, Mathilde L.; Handrich, Yves; Robin, Jean-Patrice; Weitten, Mathieu; Pevet, Paul; Kourkgy, Charlotte; Habold, Caroline

    2016-05-01

    Over the last decades, climate change and agricultural intensification have been identified as two major phenomena negatively affecting biodiversity. However, little is known about their effects on the life-history traits of hibernating species living in agro-ecosystems. The European hamster (Cricetus cricetus), once a common rodent on agricultural land, is now on the verge of extinction in France. Despite the implemented measures for its protection, populations are still in sharp decline but the reasons for it remain unclear. To investigate how environmental change has affected this hibernating rodent, we used a data set based on 1468 recordings of hamster body mass at emergence from hibernation from 1937 to 2014. We reveal the adverse effects of increasing winter rainfall and maize monoculture intensification on the body mass of wild hamsters. Given the links that exist between body mass, reproductive success and population dynamics in mammals, these results are of particular importance to understand the decline of this species. In view of the rates of maize monoculture intensification and the predicted increase in winter rainfall, it is of the utmost importance to improve land management in Western Europe to avoid the extinction of this species.

  9. Turbulent jet computations based on MRT and Cascaded Lattice Boltzmann models

    CERN Document Server

    Geller, S; Krafczyk, M

    2012-01-01

    In this contribution a numerical study of a turbulent jet flow is presented. The simulation results of two different variants of the Lattice Boltzmann method (LBM) are compared. The first is the well-established D3Q19 MRT model extended by a Smagorinsky Large Eddy Simulation (LES) model. The second is the D3Q27 Factorized Cascaded Lattice Boltzmann (FCLB) model without any additional explicit turbulence model. For this model no studies of turbulent flow with high resolution on nonuniform grids existed so far. The underlying computational procedure uses a time nested refinement technique and a grid with more than a billion DOF. The simulations were conducted with the parallel multi physics solver VIRTUALFLUIDS. It is shown that both models are feasible for the present flow case, but the FCLB outperforms the traditional approach in some aspects.

  10. Mrt, a Gene Unique to Fungi, Encodes an Oligosaccharide Transporter and Facilitates Rhizosphere Competency in Metarhizium robertsii1[C][W

    Science.gov (United States)

    Fang, Weiguo; St. Leger, Raymond J.

    2010-01-01

    The symbiotic associations between rhizospheric fungi and plants have enormous environmental impact. Fungi are crucial to plant health as antagonists of pathogens and herbivores and facilitate the uptake of soil nutrients. However, little is known about the plant products obtained by fungi in exchange or how they are transported through the symbiotic interface. Here, we demonstrate that sucrose and raffinose family oligosaccharides in root exudates are important for rhizosphere competence in the insect pathogen Metarhizium robertsii (formerly known as Metarhizium anisopliae). We identified mutants in the Metarhizium raffinose transporter (Mrt) gene of M. robertsii that grew poorly in root exudate and were greatly reduced in rhizosphere competence on grass roots. Studies on sugar uptake, including competition assays, revealed that MRT was a sucrose and galactoside transporter. Disrupting MRT resulted in greatly reduced or no growth on sucrose and galactosides but did not affect growth on monosaccharides or oligosaccharides composed entirely of glucose subunits. Consistent with this, expression of Mrt is exclusively up-regulated by galactosides and sucrose. Expressing a green fluorescent protein gene under the control of the Mrt promoter confirmed that MRT was expressed by germlings in the vicinity of grass roots but not in surrounding bulk soil. Disrupting Mrt did not reduce virulence to insects, demonstrating that Mrt is exclusively involved in M. robertsii’s interactions with plants. To our knowledge, MRT is the first oligosaccharide transporter identified and characterized in a fungus and is unique to filamentous fungi, but homologous genes in Magnaporthe, Ustilago, Aspergillus, Fusarium, Epichloe, and Penicillium species indicate that oligosaccharide transport is of widespread significance. PMID:20837701

  11. Cardiac MR imaging in arrhythmogenic heart diseases; Kardiale MRT in der Diagnostik arrhythmogener Herzerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, C.K.; Dinter, D.J.; Diehl, S.J.; Neff, K.W. [Universitaetsklinikum Mannheim, Institut fuer Klinische Radiologie, Mannheim (Germany); Papavassiliu, T.; Borggrefe, M. [Universitaetsklinikum Mannheim, Medizinische Klinik, Mannheim (Germany)

    2007-04-15

    Cardiac arrhythmias are assessed with a combination of history, clinical examination, electrocardiogram, Holter monitor, if necessary supplemented by invasive cardiac electrophysiology. In ischemic heart disease (IHD) coronary angiography is performed in addition. Echocardiography is usually the primary imaging modality. MRI is increasingly recognized as an important investigation allowing more accurate cardiac morphological and functional assessment. Approximately one-fifth of deaths in Western countries are due to sudden cardiac death, 80% of which are caused by arrhythmias. Typical causes range from diseases with high prevalence (IHD in men 30%) to myocarditis (prevalence 1-9%) and rare cardiomyopathies (prevalence HCM 0.2%, ARVC 0.02%, Brugada syndrome approx. 0.5%). The characteristic MRI features of arrhythmogenic diseases and the new aspects of characteristic distribution of late enhancement allow etiologic classification and differential diagnosis. MRI represents an important tool for detection of the underlying cause and for risk stratification in many diseases associated with arrhythmias. (orig.) [German] Herzrhythmusstoerungen werden durch die Zusammenschau von Anamnese, klinischer Untersuchung, Elektrokardiogramm, Langzeit-EKG sowie ggf. einer invasiven elektrophysiologischen Untersuchung beurteilt. Bei der koronaren Herzerkrankung (KHK) erfolgt zusaetzlich eine Koronarangiographie. Die Echokardiographie stellt das primaere bildgebende Verfahren dar. Die MRT des Herzens ermoeglicht eine genauere morphologische und funktionelle Darstellung des Herzens und gewinnt damit zunehmend an Bedeutung. Etwa jeder 5. Todesfall in westlichen Industriestaaten ist auf einen ploetzlichen Herztod zurueckzufuehren, davon sind ca. 80% durch Herzrhythmusstoerungen verursacht. Typische Ursachen reichen von Krankheiten mit hoher Praevalenz (KHK bei Maennern 30%) ueber Myokarditiden (Praevalenz 1-9%) bis zu selteneren Kardiomyopathien (Praevalenz HCM 0,2%, ARVC 0,02%, Brugada

  12. 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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-07-01

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

  14. Identification of MrtAB, an ABC transporter specifically required for Yersinia pseudotuberculosis to colonize the mesenteric lymph nodes.

    Directory of Open Access Journals (Sweden)

    Gregory T Crimmins

    Full Text Available A highly conserved virulence plasmid encoding a type III secretion system is shared by the three Yersinia species most pathogenic for mammals. Although factors encoded on this plasmid enhance the ability of Yersinia to thrive in their mammalian hosts, the loss of this virulence plasmid does not eliminate growth or survival in host organs. Most notably, yields of viable plasmid-deficient Yersinia pseudotuberculosis (Yptb are indistinguishable from wild-type Yptb within mesenteric lymph nodes. To identify chromosomal virulence factors that allow for plasmid-independent survival during systemic infection of mice, we generated transposon insertions in plasmid-deficient Yptb, and screened a library having over 20,000 sequence-identified insertions. Among the previously uncharacterized loci, insertions in mrtAB, an operon encoding an ABC family transporter, had the most profound phenotype in a plasmid-deficient background. The absence of MrtAB, however, had no effect on growth in the liver and spleen of a wild type strain having an intact virulence plasmid, but caused a severe defect in colonization of the mesenteric lymph nodes. Although this result is consistent with lack of expression of the type III secretion system by Wt Yptb in the mesenteric lymph nodes, a reporter for YopE indicated that expression of the system was robust. We demonstrate that the ATPase activity of MrtB is required for growth in mice, indicating that transport activity is required for virulence. Indeed, MrtAB appears to function as an efflux pump, as the ATPase activity enhances resistance to ethidium bromide while increasing sensitivity to pyocyanin, consistent with export across the inner membrane.

  15. Relationship between the Size of Magnetic Nanoparticles and Efficiency of MRT Imaging of Cerebral Glioma in Rats.

    Science.gov (United States)

    Semkina, A S; Abakumov, M A; Abakumov, A M; Nukolova, N V; Chekhonin, V P

    2016-06-01

    BSA-coated Fe3O4 nanoparticles with different hydrodynamic diameters (36±4 and 85±10 nm) were synthesized, zeta potential and T2 relaxivity were determined, and their morphology was studied by transmission electron microscopy. Studies on rats with experimental glioma C6 showed that smaller nanoparticles more effectively accumulated in the tumor and circulated longer in brain vessels. Optimization of the hydrodynamic diameter improves the efficiency of MRT contrast agent.

  16. MRT-92 inhibits Hedgehog signaling by blocking overlapping binding sites in the transmembrane domain of the Smoothened receptor.

    Science.gov (United States)

    Hoch, Lucile; Faure, Helene; Roudaut, Hermine; Schoenfelder, Angele; Mann, Andre; Girard, Nicolas; Bihannic, Laure; Ayrault, Olivier; Petricci, Elena; Taddei, Maurizio; Rognan, Didier; Ruat, Martial

    2015-05-01

    The Smoothened (Smo) receptor, a member of class F G protein-coupled receptors, is the main transducer of the Hedgehog (Hh) signaling pathway implicated in a wide range of developmental and adult processes. Smo is the target of anticancer drugs that bind to a long and narrow cavity in the 7-transmembrane (7TM) domain. X-ray structures of human Smo (hSmo) bound to several ligands have revealed 2 types of 7TM-directed antagonists: those binding mostly to extracellular loops (site 1, e.g., LY2940680) and those penetrating deeply in the 7TM cavity (site 2, e.g., SANT-1). Here we report the development of the acylguanidine MRT-92, which displays subnanomolar antagonist activity against Smo in various Hh cell-based assays. MRT-92 inhibits rodent cerebellar granule cell proliferation induced by Hh pathway activation through pharmacologic (half maximal inhibitory concentration [IC50] = 0.4 nM) or genetic manipulation. Using [(3)H]MRT-92 (Kd = 0.3 nM for hSmo), we created a comprehensive framework for the interaction of small molecule modulators with hSmo and for understanding chemoresistance linked to hSmo mutations. Guided by molecular docking and site-directed mutagenesis data, our work convincingly confirms that MRT-92 simultaneously recognized and occupied both sites 1 and 2. Our data demonstrate the existence of a third type of Smo antagonists, those entirely filling the Smo binding cavity from the upper extracellular part to the lower cytoplasmic-proximal subpocket. Our studies should help design novel potent Smo antagonists and more effective therapeutic strategies for treating Hh-linked cancers and associated chemoresistance. © FASEB.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-08-15

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

  18. 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.)

  19. 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.)

  20. A multiphase three-dimensional multi-relaxation time (MRT) lattice Boltzmann model with surface tension adjustment

    Science.gov (United States)

    Ammar, Sami; Pernaudat, Guillaume; Trépanier, Jean-Yves

    2017-08-01

    The interdependence of surface tension and density ratio is a weakness of pseudo-potential based lattice Boltzmann models (LB). In this paper, we propose a 3D multi-relaxation time (MRT) model for multiphase flows at large density ratios. The proposed model is capable of adjusting the surface tension independently of the density ratio. We also present the 3D macroscopic equations recovered by the proposed forcing scheme. A high order of isotropy for the interaction force is used to reduce the amplitude of spurious currents. The proposed 3D-MRT model is validated by verifying Laplace's law and by analyzing its thermodynamic consistency and the oscillation period of a deformed droplet. The model is then applied to the simulation of the impact of a droplet on a dry surface. Impact dynamics are determined and the maximum spread factor calculated for different Reynolds and Weber numbers. The numerical results are in agreement with data published in the literature. The influence of surface wettability on the spread factor is also investigated. Finally, our 3D-MRT model is applied to the simulation of the impact of a droplet on a wet surface. The propagation of transverse waves is observed on the liquid surface.

  1. Preoperative MRT of the breast in invasive lobular carcinoma in comparison with invasive ductal carcinoma; Praeoperative MRT der Brust beim invasiv-lobulaeren im Vergleich zum invasiv-duktalen Karzinom

    Energy Technology Data Exchange (ETDEWEB)

    Diekmann, F.; Diekmann, S.; Beljavskaja, M.; Taupitz, M.; Hamm, B. [Inst. fuer Radiologie, Universitaetsklinikum Charite, Berlin (Germany); Bick, U. [Inst. fuer Radiologie, Universitaetsklinikum Charite, Berlin (Germany); Dept. of Radiology, The Univ. of Chicago (United States); Blohmer, J.U. [Klinik und Poliklinik fuer Gynaekologie und Geburtshilfe, Universitaetsklinikum Charite, Berlin (Germany); Winzer, K.J. [Brustzentrum, Universitaetsklinikum Charite, Berlin (Germany)

    2004-04-01

    of ILC in CM might be the reason for the fact that preoperative MRI is particularly useful in patients with ILC. (orig.) [German] Zielsetzung: Evaluation des Stellenwerts vom praeoperativen MRT beim invasiv-lobulaeren Karzinom (ILC) im Vergleich zum invasiv-duktalen Karzinom (IDC) der Brust. Material und Methodik: Ueber ein Jahr hinweg wurde bei allen Patientinnen (n=128), bei denen im Rahmen einer Routineuntersuchung ein mammographisch und/oder sonographisch malignomsuspekter Befund aufgefallen war und die ueber die hauseigne Poliklinik fuer Gynaekologie eingewiesen worden waren, praeoperativ eine MRT-Untersuchung der Brust durchgefuehrt. Retrospektiv wurden alle histologischen Befunde auf das Vorliegen eines ILC analysiert. Dies war bei 17 Patientinnen der Fall. Die MRT-Befunde dieser Patientinnen wurden dann mit 30 zufaellig ausgewaehlten Patientinnen des gleichen Zeitraums verglichen, die eine praeoperative MRT mit anschliessender histologischer Sicherung eines IDC bekommen hatten. Dabei wurden die Ergebnisse bezueglich der Anzahl der zusaetzlich gefundenen Herde beider Gruppen miteinander mittels T-Test fuer gepaarte Stichproben verglichen. Ergebnisse: Bei den ingesamt 17 Patientinnen mit ILC wurden von den histologisch gesicherten Herden mit den konventionellen Verfahren (Mammographie/Sonographie) 21 maligne Herdbefunde gefunden, mithilfe der MRT insgesamt 30 anschliessend gesicherte maligne Herde. Bei 7 von 17 Patientinnen mit ILC wurde mindestens ein zusaetzlicher, vorher nicht bekannter maligner Herd in der MRT gefunden. Dem stehen nur 3 von 30 Patientinnen mit IDC gegenueber, bei denen ein zusaetzlicher Herd mit MRT gefunden wurde. Bei einer Patientin mit ILC wurde ein zusaetzlicher, mit den konventionellen Verfahren noch nicht bekannter Herdbefund auf der Gegenseite gefunden, was bei den Patientinnen mit IDC in keinem Fall gelang. Der Mittelwert der detektierten malignen Laesionen im MRT was statistisch signifikant hoeher als der Mittelwert der durch

  2. Advanced MRI techniques of the fetal brain; Zukunftsweisende MRT-Techniken des fetalen Gehirns

    Energy Technology Data Exchange (ETDEWEB)

    Schoepf, V.; Dittrich, E.; Berger-Kulemann, V.; Kasprian, G.; Kollndorfer, K.; Prayer, D. [Medizinische Universitaet Wien, Abteilung fuer Neuroradiologie und Muskuloskelettale Radiologie, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria)

    2013-02-15

    Evaluation of the normal and pathological fetal brain. Magnetic resonance imaging (MRI). Advanced MRI of the fetal brain. Diffusion tensor imaging (DTI) is used in clinical practice, all other methods are used at a research level. Serving as standard methods in the future. Combined structural and functional data for all gestational ages will allow more specific insight into the developmental processes of the fetal brain. This gain of information will help provide a common understanding of complex spatial and temporal procedures of early morphological features and their impact on cognitive and sensory abilities. (orig.) [German] Evaluierung des gesunden bzw. pathologischen fetalen Gehirns. Die Magnetresonanztomographie. Zukunftsweisende Techniken in der MRT-Bildgebung des fetalen Gehirns. Die Diffusionstensorbildgebung (DTI) befindet sich bereits in der klinischen Anwendung, alle anderen Methoden sind bisher noch als experimentell zu werten. Auf dem Weg zur Etablierung als Standardverfahren. Eine kombinierte Verarbeitung funktioneller und struktureller Daten, modelliert fuer jede Schwangerschaftswoche, wird es zukuenftig ermoeglichen, anhand dieser fusionierten Informationen einen praezisen Einblick in den Entwicklungsprozess des Gehirns zu erlangen. Diese Erkenntnisse und Ergebnisse werden entscheidend zur Klaerung des zeitlichen Verlaufs und des komplexen Aufbaus frueher morphologischer Auffaelligkeiten beitragen sowie deren Einfluss auf kognitive und sensorische Faehigkeiten aufzeigen. (orig.)

  3. Complex Inversion of MRT Signals under Different Loop Configurations for Groundwater Exploration.

    Science.gov (United States)

    Chen, Bin; Hu, Xiangyun; Li, Jianhui; Liu, Yajun

    2017-03-01

    Surface nuclear magnetic resonance (SNMR) is a relatively new geophysical method for non-invasive groundwater exploration and aquifer characterization. Conventional SNMR surveys based on one-dimensional (1-D) inversion of amplitude data recorded only using coincident loops provide limited or distorted groundwater distribution information, especially in regions with strong lateral heterogeneity and complicated hydrological environments. The simplistic approach limits the applicability and efficiency of SNMR, which was therefore made more effective in this study using a sophisticated signal response formulation. The elliptical polarization parameters of the excitation magnetic fields and 2-D sensitivity kernels (including real and imaginary parts) of three commonly used loop configurations were first calculated. After all the individual complex signals of five simulated measurement series along a profile were incorporated. The 2-D magnetic resonance tomography (MRT) complex inversion scheme was then used to perform high resolution tomography of synthetic models under the three loop configurations, taking full advantage of the different sensitivity distributions offered by the different loop configurations and the high sensitivity of the imaginary parts of signals to deep structures. Contrast analyses of the tomographic results showed that the complex inversions significantly decreased model ambiguities and increased depth resolution even with artificial noise added. Coincident loop measurements usually gave the best vertical resolution, and separated loops provided better lateral resolution. However, various factors would influence phase data, meaning that the complex inversion of field data is neither very reliable nor very common at present. © 2016, National Ground Water Association.

  4. The relationships between half-life (t1/2) and mean residence time (MRT) in the two-compartment open body model.

    Science.gov (United States)

    Sobol, Eyal; Bialer, Meir

    2004-05-01

    In the one-compartment model following i.v. administration the mean residence time (MRT) of a drug is always greater than its half-life (t(1/2)). However, following i.v. administration, drug plasma concentration (C) versus time (t) is best described by a two-compartment model or a two exponential equation:C=Ae(-alpha t)+Be(-beta t), where A and B are concentration unit-coefficients and alpha and beta are exponential coefficients. The relationships between t(1/2) and MRT in the two-compartment model have not been explored and it is not clear whether in this model too MRT is always greater than t(1/2). In the current paper new equations have been developed that describe the relationships between the terminal t(1/2) (or t(1/2 beta)) and MRT in the two-compartment model following administration of i.v. bolus, i.v. infusion (zero order input) and oral administration (first order input). A critical value (CV) equals to the quotient of (1-ln2) and (1-beta/alpha) (CV=(1-ln2)/(1-beta/alpha)=0.307/(1-beta/alpha)) has been derived and was compared with the fraction (f(1)) of drug elimination or AUC (AUC-area under C vs t curve) associated with the first exponential term of the two-compartment equation (f(1)=A/alpha/AUC). Following i.v. bolus, CV ranges between a minimal value of 0.307 (1-ln2) and infinity. As long as f(1)MRT>t(1/2) and vice versa, and when f(1)=CV, then MRT=t(1/2). Following i.v. infusion and oral administration the denominator of the CV equation does not change but its numerator increases to (0.307+beta T/2) (T-infusion duration) and (0.307+beta/ka) (ka-absorption rate constant), respectively. Examples of various drugs are provided. For every drug that after i.v. bolus shows two-compartment disposition kinetics the following conclusions can be drawn (a) When f(1)MRT>t(1/2). (b) When beta/alpha>ln2, then CV>1>f(1) and thus(,) MRT>t(1/2). (c) When ln2>beta/alpha>(ln4-1), then 1>CV>0.5 and thus, in order for t(1/2)>MRT, f(1) has to be greater than its

  5. 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

  6. 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

  7. MRT atlas of the lumbar spine. Herniated disk - stenosis of the spinal canal - CT-controlled injection techniques; MRT-Atlas der Lendenwirbelsaeule. Bandscheibenvorfall - Spinalkanalstenose - mit einem Beitrag zur CT-gesteuerten Injektionstechnik

    Energy Technology Data Exchange (ETDEWEB)

    Kraemer, J.; Koester, O.; Kraemer, R.; Schmid, G.

    2001-07-01

    Two thirds of all degenerative diseases of the spinal cord are located in the lumbar spinal cord. Magnetic resonance tomography has a key role in diagnosis and therapy. This atlas contains 78 examples of different diseases. More than 450 impressive images of common and infrequent findings are to improve the user's diagnostic abilities. Next to the MRT findings, also the clinical findings and the history of the disease are reported in each case, so that typical correlations are established between clinical and imaging findings. The value of diagnostic imaging techniques is characterized in order to provide comprehensive information on selective imaging of the lumbar spinal cord. (orig.)

  8. 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

  9. 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

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

    Science.gov (United States)

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

    2001-12-01

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

  11. Magnetic resonance imaging of ankle ligaments and tendon injuries; Trauma von Bandapparat und Sehnen. Untersuchungstechnik und Nachweis in der MRT

    Energy Technology Data Exchange (ETDEWEB)

    Breitenseher, M. [Abt. fuer Osteoradiologie, Universitaetsklinik und MR-Institut der Medizinischen Fakultaet, Univ. Wien (Austria)]|[Ludwig Boltzmann-Institut fuer Radiologische Tumordiagnostik, Wien (Austria); Trattnig, S. [Abt. fuer Osteoradiologie, Universitaetsklinik und MR-Institut der Medizinischen Fakultaet, Univ. Wien (Austria)]|[Ludwig Boltzmann-Institut fuer Radiologische Tumordiagnostik, Wien (Austria); Kukla, C. [Universitaetsklinik fuer Unfallchirurgie, Wien (Austria); Daebler, C. [Universitaetsklinik fuer Unfallchirurgie, Wien (Austria); Helbich, T. [Abt. fuer Osteoradiologie, Universitaetsklinik und MR-Institut der Medizinischen Fakultaet, Univ. Wien (Austria)]|[Ludwig Boltzmann-Institut fuer Radiologische Tumordiagnostik, Wien (Austria); Haller, J. [Abt. fuer Osteoradiologie, Universitaetsklinik und MR-Institut der Medizinischen Fakultaet, Univ. Wien (Austria)]|[Ludwig Boltzmann-Institut fuer Osteologie, Wien (Austria); Imhof, H. [Abt. fuer Osteoradiologie, Universitaetsklinik und MR-Institut der Medizinischen Fakultaet, Univ. Wien (Austria)]|[Ludwig Boltzmann-Institut fuer Radiologische Tumordiagnostik, Wien (Austria)

    1995-07-01

    Today MRI allows evaluation of the integrity of injured ankle ligaments. The major difficulty in MRI is inconsistency in visualization by inadequate appreciation of the three-dimensional orientation of each ankle ligament. Using this technique, 52 patients with sprained ankles underwent MRI. The integrity of rupture of the collateral lateral ligaments was obtained in all 52 ankles. Full-lenght visualization is essential for evaluation of the ankle ligaments with MRI. In these 52 patients the angle of tilt on the stress X-ray was compared with the rate of MRI findings showing an injury affecting two ligaments. We found that none of the patients in whom the angle of lateral tilt was less than 5 had rupture of two laterial ligaments, while 32% of patients with angles of tilt of 6-14 and 42% of those with angles of tilt over 15 on stress X-ray had two ruptured lateral ligaments. The advantages of MRI are that it offers the best visualization of the extent of the tendon lesion. MRI, however, seems to be superior to US in detecting and quantifying lesions of the Achilles tendon. Therefore, MRI may be indicated in particularly difficult cases of tendons injuries in the foot. (orig.) [Deutsch] Die MRT erlaubt die ausgezeichnete direkte Darstellung und sicheren Nachweis der Bandverletzung. Mit dieser Methode wurden 52 Patienten untersucht. In allen Faellen konnten die lateralen Sprunggelenkbaender bzw. Bandrupturen nachgewiesen werden. Zur optimalen Banddarstellung am Sprunggelenk ist es notwendig, die Untersuchungsebene dem Banverlauf anzupassen. Bei diesen 52 Patienten wurde der Winkel der Aufklappbarkeit in der Stressradiographie mit der Rate von Zeibandverleztungen in der MRT verglichen. Es zeigte sich, dass in der Gruppe mit einer lateralen Aufklappbarkeit {<=}5 keine Zweibandverletzung, in der Gruppe von 6-14 in 32% Zweibandverletzungen und in der Gruppe von {>=}15 42% Zweibandverletzungen vorlagen. Bei inkonklusivem Ultraschall und komplexen Sehnenveraenderungen ist

  12. Injured lateral ankle ligaments: technique and assessment of MRI; Verletzungen des Aussenbandapparates am oberen Sprunggelenk: Untersuchungstechnik und Nachweis mittels MRT

    Energy Technology Data Exchange (ETDEWEB)

    Breitenseher, M.J. [Besondere Klinische Einrichtung Magnet Resonanz und Abt. fuer Osteoradiologie, Universitaets-Kliniken fuer Radiodiagnostik, Wien (Austria)]|[Ludwig Boltzmann Inst. fuer Radiologische Tumordiagnostik, Wien (Austria); Trattnig, S. [Besondere Klinische Einrichtung Magnet Resonanz und Abt. fuer Osteoradiologie, Universitaets-Kliniken fuer Radiodiagnostik, Wien (Austria)]|[Ludwig Boltzmann Inst. fuer Radiologische Tumordiagnostik, Wien (Austria); Kukla, C. [Universitaetsklinik fuer Unfallchirurgie, Wien (Austria); Gaebler, C. [Universitaetsklinik fuer Unfallchirurgie, Wien (Austria); Kaider, A. [Inst. fuer Medizinische Computerwissenschaften, Abt. Klinische Biometrie, Univ. Wien (Austria); Haller, J. [Radiologische Abt., Hanuschkrankenhaus, Wien (Austria)]|[Ludwig Boltzmann Inst. fuer Osteologie, Wien (Austria); Heinz-Peer, G. [Besondere Klinische Einrichtung Magnet Resonanz und Abt. fuer Osteoradiologie, Universitaets-Kliniken fuer Radiodiagnostik, Wien (Austria)]|[Ludwig Boltzmann Inst. fuer Radiologische Tumordiagnostik, Wien (Austria); Imhof, H. [Besondere Klinische Einrichtung Magnet Resonanz und Abt. fuer Osteoradiologie, Universitaets-Kliniken fuer Radiodiagnostik, Wien (Austria)]|[Ludwig Boltzmann Inst. fuer Radiologische Tumordiagnostik, Wien (Austria)

    1996-03-01

    56 patients with the clinical diagnosis of sprained ankles were investigated. Evaluation of the anterior (AFTL) and posterior fibulotalar ligament (PFTL) was performed with the foot in dorsiflexion (20 ) and of the fibulo calcanear ligament (FCL) in plantarflexion (45 ). Axial T{sub 1}w-SE and T{sub 2}w-TSE images were obtained. Full-length visualisation of ligmaments in one slice and the extent of injury were evaluated. 12 ankle injuries were confirmed by operation. With MRI full-length visualisation of lateral ankle ligaments was possible in 86%. A partial/complete rupture of the AFTL was noticed in 33/64% and of the FCI in 29/39%, and of the PFTL in 27/5%. Sensitivity/specificity of MRI when compared to surgery was 100/100% for injuries of the AFTL, 64/100% for the FCL, and 33/78% for the PFTL. (orig./MG) [Deutsch] 56 Patienten wurden mit der klinischen Diagnose einer frischen Supinationsverletzung des oberen Sprunggelenkes untersucht. Das Lig. talofibulare anterius (TFA) und posterius (TFP) wurden mit dorsalflektiertem Fuss (20 ) und das Lig. calcaneofibulare (CF) mit plantarflektiertem Fuss (45 ) mit axialen T{sub 1}- und T{sub 2}-gewichteten Turbo-Spin-Echo-Sequenzen untersucht. Die Darstellbarkeit der Baender und das Verletzungsausmass wurden ausgewertet. Von 12 Patienten wurde die MRT mit der Operation verglichen. Eine optimale Darstellbarkeit eines Bandes in einer Schicht war in 86% mit der MRT moeglich. Partielle und komplette Rupturen fanden sich fuer das TFA in 33/64%, fuer das CF in 29/39% und fuer das TFP in 27/5%. Der Vergleich von MRT zur Operation ergab fuer das Erkennen einer Verletzung des TFA eine Sensitivitaet/Spezifitaet von 100/100%, fuer das CF 64/100% und fuer das FTP 33/78%. (orig./MG)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-08-15

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

  14. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  16. 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)

  17. 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

  18. 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

  19. Application of ultrahigh-field MRI in neuro-oncology; Anwendungen der Ultrahochfeld-MRT in der Neuroonkologie

    Energy Technology Data Exchange (ETDEWEB)

    Radbruch, A. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie, Neuroonkologische Bildgebung (E012), Heidelberg (Germany); Radiologische Klinik, Universitaet Heidelberg, Abteilung Neuroradiologie, Heidelberg (Germany); Schlemmer, H.P. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie, Heidelberg (Germany)

    2013-05-15

    The introduction of high-field magnetic resonance imaging (MRI) into neuro-oncological imaging allows improved visualization of tumor structures even in the field of T1 and T2-weighted imaging. Susceptibility-weighted imaging (SWI) and time of flight (TOF) angiography in particular greatly benefit from the high field strength. The visualization of tumor vasculature in MRI, which was made possible by high-field technology can potentially be applied to monitoring antiangiogenic therapy. Cerebral metastases can potentially be discovered earlier using high-field technology. Furthermore, high-field technology permits the use of new technologies, such as sodium imaging, which is expected to provide new information in the field of tumor pathophysiology. (orig.) [German] Die Einfuehrung der Hochfeld-MRT ermoeglicht in der neuroonkologischen Bildgebung bereits im Bereich der T1- und T2-gewichteten Bildgebung eine bessere Darstellung der Tumorstrukturen. Insbesondere aber die suszeptibilitaetsgewichtete Bildgebung (SWI) und die Time-of-flight(TOF)-Angiographie profitieren in erhoehtem Masse von der hohen Feldstaerke. Die durch die Hochfeldtechnologie moegliche Darstellung der Tumorgefaesse in der MRT kann potenziell fuer das Monitoring antiangiogener Therapien genutzt werden. Zerebrale Metastasen koennen mit Hilfe der Hochfeldtechnologie potenziell frueher entdeckt werden. Weiterhin ermoeglicht die Hochfeldtechnologie die Anwendung neuer Techniken wie beispielsweise der Natriumbildgebung, welche einen weiteren Erkenntnisgewinn im Bereich der Tumorpathophysiologie erwarten lassen. (orig.)

  20. Modelling Escherichia coli concentration in a wastewater reservoir using an operational parameter MRT%FE and first order kinetics.

    Science.gov (United States)

    Cirelli, Giuseppe Luigi; Consoli, Simona; Juanicó, Marcelo

    2009-01-01

    The operational parameter MRT%FE, representing the mean residence time of different ages fractions of effluent within a completely mixed reactor, was evaluated and integrated with first order kinetics. The parameter was used to model Escherichia coli concentrations in a municipal wastewater reservoir managed under different operating conditions (continuous and discontinuous). The study was conducted during 2004-2005 in a reservoir receiving effluents from the activated sludge treatment plant of Caltagirone (Eastern Sicily - Italy). The analytical approach is applied to the hydraulic state variables of the system (daily stored volumes, inlet and outlet flows), and the physical-chemical (pH, temperature, EC, TSS, BOD(5), COD) and bacteriological wastewater parameters (E. coli, FC, FS). In order to evaluate the reliability of the proposed approach, predicted E. coli concentrations within the reservoir were compared with measured ones by the correlation coefficient, F-test and Sperman's index. The study included the evaluation of die-off coefficient K(T) (d(-1)), light extinction coefficient K (m(-1)) and their relationships with climatic factors. Results of the study confirm that E. coli removal is related to the fractions of fresh effluent remaining each day within the reservoir with MRT%FE of about 5-8d, significantly lower than the nominal detention time (about 27d). The E. coli die-off coefficient (K(T)) was higher during system discontinuous operations and correlated with incident solar radiation and water temperature.

  1. MRT-measurements of muscle volumes of the lower extremities of youths with spastic hemiplegia caused by cerebral palsy.

    Science.gov (United States)

    Lampe, Renée; Grassl, Stefan; Mitternacht, Jürgen; Gerdesmeyer, Ludger; Gradinger, Reiner

    2006-09-01

    After long term of studies from our gait lab, the typical muscular dysbalances by all of our patients with cerebral palsy where pointed out. Now we wanted to examine using the MRT, weather the dysbalances of the hemiparetic musculoskeletal system also show up in discrepancies of the muscle volumes. The MRT slices of the lower extremities were segmented. From this cross sections the muscles volumes were derived. These where analyzed particularly with regard to asymmetries between spastic and healthy side. Hemiparetic patients showed reduced volumes of all muscles on the paretic leg in comparison to the healthy side. The muscles of the thigh of the paretic leg were reduced to 84% in the mean over all muscles and in comparison to the healthy leg. The volume of the muscles of the shank was reduced to 72%, significantly more than the muscles of the thigh. Concerning flexor and extensor muscles located at thigh and shank of the paretic leg there was found significantly the same relative deficit of the muscle volume. Examining the muscle volumes of subjects with different neurogene foot deformities, significant differences of the volume reduction of single muscles appeared within the lower leg.

  2. 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

  3. Cine MRI of the thorax in patients with pectus excavatum; CINE-MRT des Thorax bei Patienten mit Pectus excavatum

    Energy Technology Data Exchange (ETDEWEB)

    Herrmann, K.A.; Zech, C.J.; Schoenberg, S.O.; Reiser, M.F. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Institut fuer Klinische Radiologie, Muenchen (Germany); Strauss, T.; Hatz, R. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen (Germany). Klinik und Poliklinik fuer Chirurgie

    2006-04-15

    Morphologic and dynamic assessment of respiratory chest kinetics was performed in patients with pectus excavatum deformity (PE) using dynamic MRI: cine MRI. Seven consecutive patients with PE (aged 20.3 years{+-}4.0) and ten healthy volunteers of comparable age underwent real-time cine MRI of the chest during breathing on a 1.5 T MR scanner (Magnetom Sonata, Siemens Medical Systems, Erlangen, Germany) using a standard phased array body coil and a half-Fourier single-shot turbo spin echo sequence (HASTE) for dynamic imaging. During deep inspiration and expiration, single-shot sequences were performed in one slice level over 20 s at a frequency of 1 image/s covering the entire thoracic cage in three orientations. Morphology and chest kinetics in patients with PE were analyzed and compared with normal values, and typical patterns of chest kinetics were noted. Three different types of chest morphology in PE were identified: (1) the generally flattened thoracic cage, (2) the ''tilted'' sternum, and (3) the focally deepened sternum. Three patterns of motion correspond to these morphological types: (1) elevation of the sternum and the anterior thoracic wall, (2) angulated elevation of the parasternal rib cage with persistent deepening of the sternum resembling a ''wing beat'' movement, and (3) increased diaphragmatic movements with limited chest wall dynamics. Cine MRI is an adequate radiation-free diagnostic modality for the dynamic imaging of both chest morphology and chest wall kinetics in patients with PE. The pectus severity index can easily be determined and three typical movement patterns of chest wall kinetics identified. (orig.) [German] Morphologische und dynamische Darstellung typischer Bewegungsmuster der Atemmechanik bei Patienten mit Pectus excavatum (PE) mit dynamischer MRT: CINE-MRT. Sieben Patienten mit PE (Alter 20,3 Jahre {+-} 4,0) und 10 gesunde Probanden entsprechenden Alters wurden mit CINE-MRT des Thorax an

  4. Comparison of HR-SPECT and MR-imaging in the diagnosis of Perthes disease; Vergleich von HR-SPECT und MRT bei der Diagnostik des Morbus Perthes

    Energy Technology Data Exchange (ETDEWEB)

    Mellerowicz, H. [Orthopaedische Klinik und Poliklinik, Oskar-Helene-Heim, Freie Univ. Berlin (Germany); Schulze, C. [Orthopaedische Klinik und Poliklinik, Oskar-Helene-Heim, Freie Univ. Berlin (Germany); Stelling, E. [Orthopaedische Klinik und Poliklinik, Oskar-Helene-Heim, Freie Univ. Berlin (Germany); Stabell, U. [Praxis fuer Nuklearmedizin, Berlin (Germany); Schedel, H. [Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Freie Univ. Berlin (Germany)

    1993-12-31

    Children, who are supposed to suffer from M. Legg-Perthes, are diagnosed by clinical-, X-ray examination and today mostly by MRT. MRT gives the most reliable information but high cost, small availability and the demand for resting motionless during the examination is regarded as a problem, especially concerning children. The aim of our study was to evaluate 3D-HR-SPECT as an alternative diagnostic procedure to MRT. 28 children (2-12 years, mean 6,2 years) suspected of suffering from M. Legg-Perthes underwent 3D-HR-SPECT and 16 of them MRT examination. In all 28 children diagnostic assessment of M. Legg-Perthes could be achieved by HR-SPECT (incl. 4 negative cases of transient synovialitis). In 10 cases findings corresponded to MRT evaluation. The statement upon the area of necrosis was similar in both methods, but the reaction of bone to necrosis could be judged in a more differentiated way in HR-SPECT. Besides lower costs further advantages of HR-SPECT were found due to the deficit of movement artifacts (no sedation was required). A disadvantage of this method is X-ray contamination at a low level of 250-400 MBrg. To our experience HR-SPECT is an alternative to MRT for early diagnosis of M. Calve-Legg-Perthes. (orig.) [Deutsch] Bei Kindern mit klinischem Verdacht auf einen M. Perthes ist neben der Anamnese, der klinischen Untersuchung und dem konventionellen Roentgenbild heute haeufig die Durchfuehrung einer kernspintomographischen Untersuchung der naechste Schritt. Der hohen Treffsicherheit dieses Verfahrens stehen jedoch die vergleichsweise geringe Verfuegbarkeit, die hohen Kosten und die Notwendigkeit, waehrend der Untersuchung ruhig zu liegen, was vor allem juengeren Kindern nicht immer gelingt, gegenueber. Ziel unserer Studie war es, die diagnostische Wertigkeit der 3D-HR-SPECT (High Resolution - Single Photonen Emission Computed Tomography) als alternatives Verfahren zur MRT zu ueberpruefen. Hierzu wurden 28 Kinder im Alter von 2-12 Jahren mit klinischem

  5. MRT versus CT in the diagnosis of pneumonia. Evaluation of a T{sub 2}-weighted utrafast turbo-spin-echo sequence (UTSE); MRT versus CT in der Diagnostik von Pneumonien. Evaluation einer T{sub 2}-gewichteten ultraschnellen Turbo-Spin-Echo-Sequenz (UTSE)

    Energy Technology Data Exchange (ETDEWEB)

    Leutner, C.; Lutterbey, G.; Kuhl, C.K.; Flacke, S.; Schild, H.H. [Bonn Univ. (Germany). Radiologische Klinik; Gieseke, J. [Philips Medizin Systeme Unternehmensbereich der Philips GmbH, Hamburg (Germany); Glasmacher, A.; Theisen, A. [Bonn Univ. (Germany). Medizinische Universitaetsklinik; Wardelmann, E. [Bonn Univ. (Germany). Inst. fuer Pathologie; Grohe, C. [Bonn Univ. (Germany). Medizinische Poliklinik

    1999-05-01

    Purpose: To evaluate a T{sub 2}-weighted URSE sequence for the assessment of pulmonary infiltrations in comparison to CT. Methods: 28 MRT scans of 22 patients with confirmed pneumonia were recorded on a 1.5 Tesla apparatus with an expiratory and diastolic triggered, T{sub 2}-weighted ultrafast-spin-echo sequence in axial slice mode with the following parameters: TR{sub eff}/T{sub E}/Turbofactor 2000-4000/90 ms/21-23; slice thickness/separation 6/0.6 mm; FOV 360 mm; 24 slices. 24 spiral CTs (sice thickness/table advance: 1-2 mm/10 mm) were available for comparison. The separate evaluation of MRTs and CTs was performed by three radiologists in a consensus procedure with regard to pulmonary lesions (e.g., infiltration, round foci, net patterns) and image quality of the MRTs (4-step scale). Results: In 71% of the cases the CTs and MRTs agreed with the diagnosis and representation of the lesions, in 25% MRT was superior. MRT was better for the detection of pulmonary abscesses. In 93% the image quality of the MRT was very good to good. Conclusions: MRT in the technique presented here is in most cases equal to CT for the detection of pneumonia. Diagnosis of pulmonary abscesses seems to be better with MRT. (orig.) [Deutsch] Ziel: Eine T{sub 2}-gewichtete UTSE-Sequenz soll in der Beurteilung pulmonaler Infiltrate im Vergleich zur CT evaluiert werden. Methoden: 28 MRT bei 22 Patienten mit gesicherter Pneumonie wurden an einem 1,5-Tesla-Geraet mit einer exspiratorisch und diastolisch getriggerten T{sub 2}-gewichteten ultraschnellen Turbo-Spin-Echo-Sequenz in axialer Schichtfuehrung mit folgenden Sequenzparametern durchgefuehrt: TR{sub eff}/T{sub E}/-Turbofaktor 2000-4000/90 ms/21-23; Schichtdicke/-abstand 6/0,6 mm; FOV 350 mm; 24 Schichten. Zum Vergleich lagen 24 Spinal-CT (Schichtdicke/Tischvorschub/Inkrement: 10/10/8 mm, in 16 Faellen nach i.v. KM-Gabe) und 4 HR-CT vor (Schichtdicke/Tischvorschub: 1-2 mm/10 mm). Die getrennte Beurteilung von CT und MRT erfolgte durch drei

  6. Establishment and characterization of MRT cell lines from genetically engineered mouse models and the influence of genetic background on their development.

    Science.gov (United States)

    Kuwahara, Yasumichi; Mora-Blanco, E Lorena; Banine, Fatima; Rogers, Arlin B; Fletcher, Christopher; Sherman, Larry S; Roberts, Charles W M; Weissman, Bernard E

    2013-06-15

    Malignant rhabdoid tumors (MRTs) are rare, aggressive cancers occuring in young children primarily through inactivation of the SNF5(INI1, SMARCB1) tumor suppressor gene. We and others have demonstrated that mice heterozygous for a Snf5 null allele develop MRTs with partial penetrance. We have also shown that Snf5(+/-) mice that lack expression of the pRb family, due to TgT121 transgene expression, develop MRTs with increased penetrance and decreased latency. Here, we report that altering the genetic background has substantial effects upon MRT development in Snf5(+/--) and TgT121 ;Snf5(+/-) mice, with a mixed F1 background resulting in increased latency and the appearance of brain tumors. We also report the establishment of the first mouse MRT cell lines that recapitulate many features of their human counterparts. Our studies provide further insight into the genetic influences on MRT development as well as provide valuable new cell culture and genetically engineered mouse models for the study of CNS-MRT etiology. Copyright © 2012 UICC.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-05-01

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

  8. 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

  9. Therapy monitoring of neoadjuvant therapy with MRI. RECIST and functional imaging; Therapiemonitoring im MRT unter neoadjuvanter Therapie. RECIST und funktionelle Bildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Grandl, S.; Ingrisch, M.; Hellerhoff, K. [Klinikum der Ludwig-Maximilians-Universitaet, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany)

    2014-03-15

    Neoadjuvant chemotherapy is increasingly being applied in patients with operable breast cancer. Thus, an early prediction of response to neoadjuvant chemotherapy is of high relevance. The interobserver variability of clinical examination, mammography and ultrasonography in the assessment of response to neoadjuvant chemotherapy is high. Magnetic resonance imaging (MRI) allows the assessment of functional parameters in addition to changes in tumor size and morphology. A reliable therapy response monitoring aims at optimizing individualized patient care. This paper summarizes current guidelines for the assessment of response to neoadjuvant chemotherapy in breast cancer according to the response evaluation criteria in solid tumors (RECIST). Furthermore, the technical principles of MRI-based therapy monitoring are described and an overview of the clinical studies that have assessed the feasibility of functional MRI in response to treatment evaluation is given. The technology of functional MRI offers promising results concerning therapy response monitoring. However, the level of evidence is not sufficiently evaluated for the technologies of functional MRI presented here. (orig.) [German] Mit dem steigenden Einsatz der neoadjuvanten Chemotherapie bei Patientinnen mit einem primaer operablen Mammakarzinom erlangt die fruehzeitige Evaluation des Therapieansprechens eine zunehmende Bedeutung. Die klinische Untersuchung, die Mammographie und die Hochfrequenzsonographie der Brust weisen fuer das Therapiemonitoring eine hohe Interobservervariabilitaet auf. Die Magnetresonanztomographie (MRT) bietet die Moeglichkeit, neben der Tumorgroesse und der Morphologie auch funktionelle Parameter zu erfassen und somit bereits frueh im Therapieverlauf das Therapieansprechen vorherzusagen. Ziel einer fruehen zuverlaessigen Praediktion des Therapieansprechens ist die Abstimmung der Therapie auf die individuelle Patientin. Der vorliegende Beitrag fasst die aktuellen Leitlinien zum

  10. 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.)

  11. Cardiovascular whole-body MRI: possibilities and limitations in prevention; Kardiovaskulaere Ganzkoerper-MRT: Moeglichkeiten und Grenzen in der Frueherkennung

    Energy Technology Data Exchange (ETDEWEB)

    Herborn, C.U.; Vogt, F.M.; Goyen, M.; Goehde, S.C.; Ruehm, S.G.; Forsting, M. [Universitaetsklinikum Essen, Institut fuer Diagnostische und Interventionelle Radiologie (Germany)

    2004-09-01

    Cardiovascular disease is a major challenge to the healthcare with increasing prevalence in western societies. Hence, early detection of cardiovascular pathologies and preventative strategies will experience growing relevance in the future. Magnetic resonance imaging (MRI) nowadays allows a comprehensive analysis of the cardiovascular system. By combining separate examinations of brain, arterial vasculature, and heart the technique permits early detection of pathological changes with high diagnostic accuracy void of adverse events. Such a protocol has been proven feasible and technically robust and can be performed within 45 min. Inherent limitations are low spatial resolution of whole-body MR angiography and lack of functional stress testing of the heart. However, while being suitable as a fast and comprehensive imaging technique for cardiovascular screening purposes, medical consequences and socioeconomic relevance must further be elucidated. (orig.) [German] Kardiovaskulaere Erkrankungen und ihre Folgen stellen in den westlichen Laendern ein bedeutendes Gesundheitsproblem mit steigender Praevalenz dar. Der Frueherkennung und Vorsorge dieser Erkrankungen kommt deshalb in der Zukunft eine wachsende Bedeutung zu. Mit der Magnetresonanztomographie (MRT) gelingt heute eine umfassende Analyse des kardiovaskulaeren Systems. Durch die Kombination der Untersuchung von Gehirn, Gefaessen und Herz kann man frueh und nebenwirkungsfrei pathologische Veraenderungen mit hoher diagnostischer Genauigkeit erfassen. Das eingesetzte Protokoll laesst sich innerhalb von 45 min durchfuehren. Limitationen betreffen die raeumliche Aufloesung der Ganzkoerper-MR-Angiographie sowie die fehlende Untersuchung des Herzens unter Belastung. In ihrer bisherigen Form ist die MRT als schnelles und umfassendes Verfahren fuer die Frueherkennung kardiovaskulaerer Erkrankungen geeignet. Der medizinische Nutzen und die soziooekonomische Bedeutung muessen in den naechsten Jahren weiter analysiert werden

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-06-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-02-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-07-15

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

  16. 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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-05-15

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

  18. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  19. Prognostic impact of bone marrow fibrosis in polycythemia vera: validation of the IWG-MRT study and additional observations.

    Science.gov (United States)

    Barraco, D; Cerquozzi, S; Hanson, C A; Ketterling, R P; Pardanani, A; Gangat, N; Tefferi, A

    2017-03-10

    In 2012, the International Working Group for Myeloproliferative Neoplasms (MPN) Research and Treatment (IWG-MRT) reported an associations between mild bone marrow (BM) fibrosis (⩾grade 1) in polycythemia vera (PV) and a lower incidence of thrombosis during the clinical course and a higher risk of fibrotic progression. The objective in the current study of 262 patients with PV was to validate these observations and also identify other risk factors for myelofibrosis-free survival (MFFS). About 127 (48%) patients displayed ⩾grade 1 reticulin fibrosis at the time of diagnosis; presenting clinical and laboratory features were not significantly different between patients with or without BM fibrosis. In univariate analysis, BM fibrosis had no significant impact on overall, leukemia-free or thrombosis-free survival, whereas a significant association was noted for MFFS (P=0.009, hazard ratio 2.9; 95% confidence interval 1.32-6.78); other risk factors for MFFS included leukocytosis ⩾15 × 109/l, presence of palpable splenomegaly and abnormal karyotype. During multivariable analysis, leukocytosis ⩾15 × 109/l, palpable splenomegaly and ⩾grade 1 BM reticulin fibrosis remained significant. The current study validates the previously observed association between ⩾grade 1 BM reticulin fibrosis in PV and subsequent fibrotic progression, and identifies leukocytosis and palpable splenomegaly as additional risk factors for fibrotic progression; additional studies are required to clarify the impact of BM fibrosis on thrombosis and that of abnormal karyotype on MFFS.

  20. 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

    Energy Technology Data Exchange (ETDEWEB)

    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

  1. Speaker on verge of resignation

    Index Scriptorium Estoniae

    2008-01-01

    Leedu parlamendi spiikri Viktoras Muntianase umbusaldusavaldusele kirjutasid alla nii opositsiooni- kui ka koalitsiooniparteide poliitikud. Muntianas on seotud altkäemaksu skandaaliga Kaunase kruntide erastamisel

  2. 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.)

  3. Success rates of manual restorative treatment (MRT) with amalgam in permanent teeth in high caries-risk Filipino children.

    Science.gov (United States)

    Schüler, I M; Monse, B; Holmgren, C J; Lehmann, T; Itchon, G S; Heinrich-Weltzien, R

    2015-07-01

    The objective of the study is to evaluate the success rate of amalgam restorations in manually prepared cavities under field conditions within a comprehensive school-based oral health-care program in high caries-risk children. A total of 1322 restorations were placed in the permanent teeth of 619 high caries risk Filipino children by two dentists and two trained health-care workers. Only hand instruments and an encapsulated amalgam, mixed with a manually powered amalgamator, were used. The restorations were evaluated after a service time of 1 to 5 years using modified atraumatic restorative treatment (ART) criteria. The overall success rate of the amalgam restorations was 95.3% (n = 1260) after a mean service time of 2.7 years (SD = 1.4). Multiple-surface restorations showed significantly higher failure rates (11.4%) than single-surface occlusal (4.7%) and single-surface non-occlusal (2.1%) restorations; 93.6% of large restorations was performed successfully, but had a risk of failure twice to that of small restorations (odds ratio (OR) = 2.141). The score of the decayed, missing, and filled teeth (DMFT) index had significant influence on the success rate. The risk of restoration failure increased by 11.5% for each unit increase in DMFT (OR = 1.148). Neither the operator nor age nor gender of the patient had a significant effect on the success rate of the restorations. Amalgam was performed satisfactorily as a filling material when placed under field conditions in manually prepared cavities in the permanent dentition of high caries-risk children. Success of the restorations was influenced by the patient's caries experience (DMFT), restoration size, and service time. Manual restorative treatment (MRT) amalgam restorations were performed satisfactorily, but higher dental caries experience and large cavities contribute to lower success rates.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-11-01

    Aim: In this study neuronal correlates of encoding and retrieval in paired association learning were compared using two different neuroimaging methods: Positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). Methods: 6 right-handed normal male volunteers took part in the study. Each subject underwent six 0-15-butanol PET scans and an fMRI study comprising four single epochs on a different day. The subjects had to learn and retrieve 12 word pairs which were visually presented (highly imaginable words, not semantically related). Results: Mean recall accuracy was 93% in the PET as well as in the fMRI experiment. During encoding and retrieval we found anterior cingulate cortex activation, and bilateral prefrontal cortex activation in both imaging modalities. Furthermore, we demonstrate the importance of the precuneus in episodic memory. With PET the results demonstrate frontopolar activations whereas fMRI fails to show activations in this area probably due to susceptibility artifacts. In fMRI we found additionally parahippocampal activation and due to the whole-brain coverage cerebellar activation during encoding. The distance between the center-of-mass activations in both modalities was 7.2{+-}6.5 mm. Conclusion: There is a preponderance of commonalities in the activation patterns yielded with fMRI and PET. However, there are also important differences. The decision to choose one or the other neuroimaging modality should among other aspects depend on the study design (single subject vs. group study) and the task of interest. (orig.) [German] Ziel: Vergleich der beiden Bildgebungsmethoden Positronen-Emissions-Tomographie (PET) und funktionelle Magnetresonanztomographie (fMRT) bei einer deklarativen Gedaechtnisaufgabe. Methoden: 6 Probanden wurden sowohl mit einer GE 4096+PET-Kamera als auch mit einem Siemens Vision MR-Tomographen waehrend einer deklarativen Gedaechtnisaufgabe untersucht. Die Gedaechtnisaufgabe bestand darin, 12 Wortpaare

  5. CT and MRI characteristica of tumours of the temporal bone and the cerebello-pontine angle; CT und MRT tumoroeser Veraenderungen des Schlaefenbeins

    Energy Technology Data Exchange (ETDEWEB)

    Imhof, H.; Henk, C.B.; Dirisamer, A.; Czerny, C. [Abteilung fuer Osteologie/Universitaetsklinik Radiodiagnostik, Wien (Austria); Gstoettner, W. [Universitaetsklinik Hals-Nasen-Ohren-Heilkunde, Frankfurt/Main (Germany)

    2003-03-01

    selten. Diese Tumoren koennen in benigne und maligne Veraenderungen eingeteilt werden.In dieser Arbeit sollen die CT- und MRT-Charakteristika der Tumoren des Schlaefenbeins und Kleinhirnbrueckenwinkels gezeigt werden. Die Computertomographie (HRCT) wird in axialer Schichtfuehrung in der Auswertung mit hochaufloesendem Knochenfenster durchgefuehrt. Die koronalen Schichten koennen aus dem axialen Datensatz rekonstruiert oder direkt in koronaler Ebene hergestellt werden.Mit der MRT kann zunaechst mit einer FLAIR-Sequenz in axialer Ebene das gesamte Gehirn untersucht werden, um einen Tumoreinbruch nach intrakraniell auszuschliessen oder nachzuweisen.Danach werden axiale T2-gewichtete Fast-(Turbo-) Spinechosequenzen oder fettunterdrueckte Inversion-recovery-Sequenzen in hochaufloesender Technik ueber die Schlaefenbeinregion angefertigt, gefolgt von axialen T1-gewichteten Spinechosequenzen vor und nach Kontrastmittel-(KM-)Gabe in hochaufloesender Technik.Zuletzt koennen koronale T1-gewichtete Spinechosequenzen in hochaufloesender Technik mit Fettunterdrueckung nach KM-Gabe ueber die Schlaefenbeinregion durchgefuehrt werden.Die HRCT kann die knoecherne Ausdehnung und dazugehoerige Knochenveraenderungen darstellen, die MRT erfasst genau die Tumorausdehnung in den Weichteilen. Mit der HRCT und der MRT gemeinsam laesst sich die exakte Tumorausdehnung zur therapeutischen Planung bestimmen. Die HRCT zeigt die knoechernen Veraenderungen ausgezeichnet. In Einzelfaellen - wie z.B. bei Exstosen des aeusseren Gehoergangs - kann es genuegen, lediglich eine HRCT des Schlaefenbeins durchzufuehren.Aufgrund des Aggressivitaetsverhaltens des Tumors in der HRCT sind auch Rueckschluesse auf einen eher benignen oder malignen Tumortyp moeglich. Mit der MRT koennen aufgrund des sehr hohen Weichteilkontrastes auch manche Tumoren - insbesondere vaskulaere wie z.B. Glomustumoren - gewebemaessig charakterisiert und in eher benigne und maligne unterteilt werden.Somit sind die HRCT und die MRT des

  6. [131I]IAZA as a molecular radiotherapeutic (MRT) drug: wash-out with cold IAZA accelerates clearance in a murine tumor model.

    Science.gov (United States)

    Mercer, John R; McEwan, Alexander J B; Wiebe, Leonard I

    2013-06-06

    Based on animal model studies, [131I]IAZA may be useful as an adjunct radiotherapeutic (MRT) drug for the treatment of tumor hypoxia. However, radioactivity in the blood of patients and healthy volunteers dosed with [123I]IAZA has a protracted terminal elimination phase in which clearance is influenced by free [123I]IAZA and possibly by unidentified metabolites. The current work reports that about 40% of the radioactivity in human serum is associated with the serum protein fraction, and that the free:bound ratio is constant at about 60:40 for at least the first 135 min after injection, as determined by radio-HPLC analyses. In order to modulate the clearance of bound and free radioactive IAZA, nonradioactive (cold) IAZA was administered i.v. 1 h following injection of high specific activity [125I][IAZA in the Balb/C EMT-6 murine tumor model. This 'wash out' procedure reduced the concentrations of radioactivity by at least 40% in all tissues, with greatest effect in kidney and liver, and least in tumor. As a result, the tumor:blood ratio increased from 5.8 to 8.5 at 4 h post-injection. This effect would be advantageous for the use of [131I]IAZA as an MRT drug. Optimization of intervals between radioactive and wash out dose, and confirmation of the self-irradiation dose to all tissues, remain to be undertaken before [131I]IAZA can be tested as a low-dose-rate MRT supplement to external beam x-ray radiotherapy.

  7. MRI for arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C); MRT bei arrhythmogener rechtsventrikulaerer Dysplasie/Kardiomyopathie (ARVD/C)

    Energy Technology Data Exchange (ETDEWEB)

    Hunold, P. [Universitaetsklinikum Schleswig-Holstein, Campus Luebeck, Klinik fuer Radiologie und Nuklearmedizin, Luebeck (Germany)

    2013-01-15

    Arrhythmogenic right ventricular dysplasia/cardiomyopathy is a congenital disease that may present with sudden cardiac death as the first manifestation. Standards for the difficult clinical diagnosis are the so-called modified Task Force criteria that incorporate imaging-based, electrocardiographic and anamnestic information. Cardiac magnetic resonance imaging (MRI) is the standard technique for imaging of the right ventricle and can compliment the recent ARVD/C diagnosis criteria by providing exact information on right ventricular size and function. It is the most reliable modality available for the detection of right ventricular aneurysms and the quantification of ventricular size. Furthermore, MRI is able to identify areas of fatty or fibrous replacement within the right ventricular myocardium in a non-invasive way. However, a suspicion of ARVD/C cannot be confirmed or excluded based on MRI findings alone. In clinical routine cardiac MRI is an enormously important component in the ARVD/C diagnostic toolbox; however, MRI can only act as one part of the diagnostic puzzle and should exclusively be performed by experienced centers using specifically tailored protocols. (orig.) [German] Die arrhythmogene rechtsventrikulaere Dysplasie/Kardiomyopathie (ARVD/C) ist eine angeborene Erkrankung, deren Erstmanifestation haeufig der ploetzliche Herztod ist. Standard fuer die schwierige Diagnostik sind die sog. modifizierten Task-force-Kriterien, in die bildgebende, elektrokardiographische und anamnestische Befunde eingehen. Die MRT ist das Standardverfahren zur Darstellung des rechten Ventrikels. Zu den derzeit gueltigen ARVD/C-Diagnosekriterien kann die MRT exakte Informationen zu Groesse und Funktion des rechten Ventrikels liefern. Fuer die Identifizierung rechtsventrikulaerer Aneurysmata und zur Quantifizierung der Ventrikelgroesse ist die MRT die zuverlaessigste verfuegbare Methode. Darueber hinaus koennen Fibrose- und Fettareale innerhalb des rechtsventrikulaeren

  8. 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

  9. Hybrid LBM-MRT model coupled with finite difference method for double-diffusive mixed convection in rectangular enclosure with insulated moving lid

    Science.gov (United States)

    Bettaibi, Soufiene; Kuznik, Frédéric; Sediki, Ezeddine

    2016-02-01

    This paper presents a numerical study of thermosolutal mixed convection in rectangular enclosure with sliding top lid. The fluid flow is solved by the multiple relaxation time (MRT) lattice Boltzmann method (LBM), whereas the temperature and concentration fields are computed by finite difference method (FDM). The main objective of this study is to investigate the accuracy and the effectiveness of such model to predict thermodynamics for heat and mass transfer in a driven cavity. This model is validated with different numerical methods in the current literature. A good agreement is obtained between our results and previous works. The different comparisons demonstrate the robustness and the accuracy of the proposed approach.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-03-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-02-01

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

  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. Functional magnetic resonance imaging (fMRI) of motor deficits in schizophrenia; Funktionelle Magnetresonanztomographie (fMRT) bei Bewegungsstoerungen von Patienten mit Schizophrenie

    Energy Technology Data Exchange (ETDEWEB)

    Wenz, F. [Radiologische Universitaetsklinik, Heidelberg (Germany). Abt. Klinische Radiologie; Baudendistel, K. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Knopp, M.V. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Schad, L.R. J. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Schroeder, J. [Psychiatrische Universitaetsklinik, Heidelberg (Germany); Floemer, F. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Kaick, G. van [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie

    1995-04-01

    The purpose of this study was to investigate differences in the cerebral activation pattern in ten schizophrenic patients and ten healthy volunteers using functional MRI. fMRI was performed using a modified FLASH sequence (TR/TE/{alpha}=100/60/40 ) and a conventional 1.5 T MR scanner. Colorcoded statistical parametric maps based on Student`s t-test were calculated. Activation strength was quantified using a 5x6 grid overlay. The volunteers showed a higher activation strength during left hand movement compared to right hand movement. This lateralization effect was reversed in patients who showed overall reduced activation strength. Disturbed interhemispheric balance in schizophrenic patients during motor task performance can be demonstrated using fMRI. (orig.) [Deutsch] In dieser Studie sollten Veraenderungen im zerebralen Aktivierungsmuster bei 10 schizophrenen Patienten im Vergleich zu 10 gesunden Probanden mit der fMRT untersucht werden. Wir benutzten eine modifizierte FLASH-Sequenz (TR/TE/{alpha}=100/60/40 ) und einen konventionellen 1,5-T-MR-Tomographen. Farbkodierte t-Testbilder wurden berechnet und mit Hilfe eines ueberlagerten 5x6-Gitters quantitativ ausgewertet. Bei den Probanden induzierte die Bewegung der linken Hand eine hoehere Aktivierung als die Bewegung der rechten Hand. Dieses Lateralisationsverhalten war bei den Patienten, die eine insgesamt verminderte Aktivierungsstaerke zeigten, umgekehrt. Bei schizophrenen Patienten konnte mittels fMRT eine veraenderte Interhemisphaeren-Balance gezeigt werden. (orig.)

  14. Revised response criteria for myelofibrosis: International Working Group-Myeloproliferative Neoplasms Research and Treatment (IWG-MRT) and European LeukemiaNet (ELN) consensus report.

    Science.gov (United States)

    Tefferi, Ayalew; Cervantes, Francisco; Mesa, Ruben; Passamonti, Francesco; Verstovsek, Srdan; Vannucchi, Alessandro M; Gotlib, Jason; Dupriez, Brigitte; Pardanani, Animesh; Harrison, Claire; Hoffman, Ronald; Gisslinger, Heinz; Kröger, Nicolaus; Thiele, Juergen; Barbui, Tiziano; Barosi, Giovanni

    2013-08-22

    The current document is a revision of the International Working Group-Myeloproliferative Neoplasms Research and Treatment (IWG-MRT) criteria for treatment response in myelofibrosis (MF) and represents a collaborative effort by the IWG-MRT and the European LeukemiaNet to objectively assess the value of new drugs in inducing morphologic remission or improvement in MF-associated symptomatic burden (MF-SB). Some of the changes in the current revision include stricter definitions of red cell transfusion dependency and independency and consideration of the Myeloproliferative Neoplasm Symptom Assessment Form as a tool to quantify meaningful changes in disease-related symptoms. Six response categories are listed: complete remission (CR) and partial remission signify treatment effects that are consistent with disease modification, whereas drug-induced improvements in MF-SB were annotated as clinical improvement, anemia response, spleen response, or symptoms response. Additional criteria are provided for progressive disease, stable disease, and relapse. The document also includes recommendations for assessing cytogenetic and molecular remissions, without mandating their inclusion for CR assignment.

  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. MRI and sonography for diagnostic examination of cervico-thoracal lymphangioma: a radio-histological comparison; MRT und Sonographie in der Diagnostik zervikothorakaler Lymphangiome: Ein radio-histologischer Vergleich

    Energy Technology Data Exchange (ETDEWEB)

    Theobald, I. [Abt. Radiodiagnostik, Univ. Heidelberg (Germany); Roeren, T. [Abt. Radiodiagnostik, Univ. Heidelberg (Germany); Betsch, B. [Abt. Paediatrische Radiologie, Univ. Heidelberg (Germany); Magener, A. [Abt. Pathologie, Univ. Heidelberg (Germany); Kauffmann, G.W. [Abt. Radiodiagnostik, Univ. Heidelberg (Germany)

    1996-07-01

    Sonography and MRI yield typical signs and criteria that enable distict diagnosis of lymphangioma. For differential diagnosis of the hemangioma, MRI proves to be better than sonography due to the typical contrast agent effects. In addition, MRI delivers results that unambiguously deliminate the size and topography of the tumor in a pre-operative scan and, other than the sonography, is not restricted in its value due to artefact overlapping and penetration depth. Although MRI thus delivers decisive information, its insufficient diagnostic specificity does not allow classification of cystic tumors of the neck. This applies also to other, similar tumor morphologies, such as cysts in the neck, cystic teratoma, and cystic cavernous angioma. (orig.) [Deutsch] Mittels Sonographie und MRT lassen sich Lymphangiome anhand typischer Kriterien diagnostizieren. In der Differentialdiagnose ``Haemangiom`` ist die MRT der Sonographie aufgrund des typischen KM-Verhaltens ueberlegen. Zusaetzlich kann die MRT im Vergleich zur Sonographie praeoperativ eindeutig die Groessse und Topographie des Tumors klaeren. Sie ist nicht, wie die Sonographie, durch Artefaktueberlagerungen und Eindringtiefe limitiert. Obwohl die MRT damit entscheidende Informationen liefert, ist sie bzgl. ihrer Spezifitaet zur Klassifikation zystischer Halstumoren unzureichend. Die genannte Morphologie trifft auch auf andere Tumoren wie z.B. Halszysten, zystische Teratome, zystisch-kavernoese Angiome zu. (orig.)

  17. 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

  18. 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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-11-01

    Aim: To evaluate the influence of MRI of the temporomandibular joint on the therapeutic strategy in patients with craniomandibular disorders (internal derangement) and, furthermore, to analyze interobserver agreement for defined MRI criteria. Materials and Methods: Fifty-one unilateral and bilateral MRI examinations of 32 patients were enrolled. Therapeutic strategies before and after performance of the MRI were compared. Retrospectively, two radiologists independently analyzed the MR images for position of the disk, position of the condyle, signal intensity of the disk and bilaminar zone, osseous changes and several additional findings, using a check list. Agreement was tested by kappa statistics. Results: In 56% of the cases, changes of the therapeutic regimen were registered after MRI. Statistically significant agreement of the two observers was found for anterior position of the disk (kappa=0.44), transverse position of the disk (kappa=0.46) and position of the condyle (kappa=0.45). No significant agreement was found for signal intensity of the disk (kappa=0.14) or bilaminar zone (kappa=0.24), osseous changes (kappa=0.13) and the additional findings (kappa=0.29). Discussion: MRI has a measurable impact on the therapeutic approach to the internal derangement of the TMJ. The position of the disk and condyle can be reproducibly judged, while the signal intensity of the disk and bilaminar zone and the osseous changes are subject to wide observer variations. (orig.) [German] Zielsetzung: Es sollte der Einfluss der MRT des Kiefergelenkes auf die Therapieentscheidung untersucht werden. Des Weiteren sollten Uebereinstimmungen zweier unabhaengiger Radiologen in der Beurteilung von Kiefergelenk MRT anhand definierter Kriterien bestimmt werden. Material und Methoden: 51 MR-Untersuchungen des Kiefergelenkes wurden ausgewertet. Bei diesen Patienten wurde das urspruengliche mit dem Behandlungskonzept nach MRT verglichen. Alle MRT wurden von zwei Radiologen ausgewertet. Die

  20. Dynamic MRI of the lumbar spine for the evaluation of microcirculation during anti-angiogenetic therapy in patients with myelodysplastics syndromes; Dynamische MRT der Lendenwirbelsaeule zur Beurteilung der Mikrozirkulation unter anti-angiogenetischer Therapie bei Patienten mit myelodysplastischen Syndromen

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, A.; Wittsack [Institut fuer Diagnostische Radiologie, Duesseldorf (Germany); Strupp, C. [Klinik fuer Haematologie, Onkologie und klinische Immunologie, Duesseldorf (Germany); Engelbrecht, V. [Institut fuer Diagnostische Radiologie, Duesseldorf (DE)] (and others)

    2002-02-01

    Material and Methods: In 20 healthy normal persons and 28 MDS patients a dynamic contrast-enhanced MRI (d-MRI) of the lumbar spine was performed. After the initial d-MRI-investigation 24 of the 28 MDS patients received an antiangiogenetic therapy with thalidomide. With an average of 4.2 months after the beginning of therapy a d-MRI-follow-up examination in 9 of these patients was performed. The amplitude and exchange-rate constant were calculated and a statistical comparison of these values between healthy persons and MDS patients as well as a correlation with the clinical course was executed. Results: Compared with the normal controls the MDS patients showed a higher amplitude (normal persons: 14.4{+-}5.2, MDS: 24.8{+-}8.1) and exchange-rate constant (normal persons: 0.124{+-}0.042, MDS: 0.136{+-}0.036). In 7 of 9 MDS patients undergoing thalidomide therapy a reduction of the amplitude and exchange rate constant values was evident in the d-MRI follow-up examinations. Clinically these patients showed a therapy response with complete or partial disease remission. (orig.) [German] Material und Methode: Bei 20 gesunden Normalpersonen und 28 MDS-Patienten wurde eine kontrastmittelunterstuetzte dynamische MRT (d-MRT) der LWS durchgefuehrt. Bei 24 der 28 MDS-Patienten wurde nach der initialen d-MRT-Untersuchung eine anti-angiogenetische Therapie mit Thalidomid begonnen. Durchschnittlich 4,2 Monate nach Therapiebeginn erfolgte bei 9 dieser Patienten eine d-MRT-Verlaufsuntersuchung. Anhand der Signalintensitaets-Zeit-Kurven der d-MRT wurden die Amplitude und Austauschratenkonstante berechnet und ein statistischer Vergleich der Werte zwischen Probanden und Patienten sowie eine Korrelation der klinischen Verlaufsparameter der MDS-Patienten mit den d-MRT-Ergebnissen durchgefuehrt. Ergebnisse: Bei den 28 MDS-Patienten wurden im Vergleich zu den Normalpersonen durchschnittlich hoehere Amplituden (Normalpersonen: 14,4{+-}5,2, MDS: 24,8{+-}8,1) und Austauschratenkonstanten

  1. 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

  2. Whole-body staging of malignant melanoma. Advantages, limitations and current importance of PET-CT, whole-body MRI and PET-MRI; Ganzkoerperdiagnostik beim malignen Melanom. Vorteile, Grenzen und aktueller Stellenwert von PET-CT, GK-MRT und PET-MRT

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    Pfannenberg, C.; Schwenzer, N. [Eberhard-Karls-Universitaet Tuebingen, Abteilung Diagnostische und Interventionelle Radiologie, Tuebingen (Germany)

    2015-01-16

    (GK)-Stagingmethoden, wie die {sup 18}F-Fluordeoxyglukose(FDG)-Positronenemissionstomographie(PET)-CT und GK-MRT zunehmend ersetzt, da diese Methoden eine GK-Untersuchung in vertretbarer Zeit mit hoher diagnostischer Genauigkeit bieten. Zahlreiche Studien belegen die hohe Sensitivitaet (> 85 %) und Spezifitaet (> 90 %) der FDG-PET-CT beim Nachweis von Melanommetastasen, welche die Treffsicherheit der konventionellen Stagingmethoden, insbesondere der CT, uebertreffen und bis zu einem Drittel der Faelle zu einer Aenderung des therapeutischen Managements fuehren. Dies gilt insbesondere fuer das Staging vor einer kurativen Metastasenchirurgie. Die begrenzte Sensitivitaet der PET fuer Laesionen kleiner als 1 cm und die mangelnde Faehigkeit, mikroskopische Metastasen zu entdecken, limitieren den Nutzen der PET-CT fuer Patienten mit Melanom im Stadium I und II. Bei fehlender praktischer und oekonomischer Verfuegbarkeit der PET-CT koennen im klinischen Alltag die GK-CT oder GK-MRT alternativ eingesetzt werden. Die GK-MRT einschliesslich Diffusionswichtung (''diffusion-weighted imaging'', DWI) hat sich zu einer konkurrenzfaehigen Alternative zur PET-CT entwickelt, prospektive vergleichende Studien sind allerdings noch selten und weisen zudem kleine Fallzahlen und ein heterogenes Studiendesign auf. Betrachtet man die Genauigkeit der beiden Methoden, bezogen auf die verschiedenen Metastasenlokalisationen, wird deutlich, dass Sensitivitaet und Spezifitaet von PET-CT und GK-MRT organabhaengig differieren. Es zeigen sich Vorteile der PET-CT in der Detektion von Lymphknoten-, Weichteil- und Lungenmetastasen und eine Ueberlegenheit der MRT fuer Hirn-, Leber- und Knochenlaesionen. Der Stellenwert der PET-MRT fuer die Ausbreitungsdiagnostik beim Melanom wird derzeit in klinischen Studien geprueft. (orig.)

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

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    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

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

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    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.).

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

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    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

  6. MRI-based N-staging in esophageal cancer; N-Staging des Oesophaguskarzinoms mittels MRT unter Verwendung von artefaktreduzierenden LOTA-Sequenzen

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    Krupski, G.; Lorenzen, J.; Nicolas, V.; Adam, G. [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Abt. fuer Diagnostische und Interventionelle Radiologie; Gawad, K.; Izbicki, J.R. [Universitaetsklinikum Hamburg-Eppendorf, Hamburg (Germany). Abt. fuer Allgemeinchirurgie

    2002-10-01

    Purpose: For planning the therapeutic strategies and estimating the prognosis in esophageal cancer, N-staging is very important. To date, MRI still is of minor importance as imaging modality of the mediastinum despite promising developments in the past, like ECG-gating or 'averaging' sequences, e.g. LOTA (Long-term averaging), which facilitate mediastinal and thoracic MR-imaging. In a prospective approach, the value of MRI based N-staging was examined with respect to LOTA-sequences. Material and Methods: Within from weeks prior to esophagectomy, standardized MRI of the esophagus was performed in 15 patients (10 squamous-cell-carcinomas and 5 adenocarcinomas) using a 1.5 T whole body scanner. Imaging quality was classified based on depiction of aortic wall or tracheal wall layers. Criteria for malignant infiltration were a diameter of more than 15 mm or a round appearance of a lymph node together with GD-DTPA enhancement. All data were blinded and separately read by two radiologists. The data of the study were compared with those from the pathological workup of the resected specimen. Results: MRI had a sensitivity of 100% and a specificity of 78% for lymph node metastases. Due to incomplete depiction of the celiac trunk (M1), nodal metastasis in a non-enlarged node was missed. Conclusion: With modern MRI, N-staging is almost as accurate as the gold standard endoscopic ultrasound and should particularly be used in patients not suited for an endoscopic ultrasound examination. (orig.) [German] Ziel: Fuer die Therapieplanung und Einschaetzung der Prognose des Oesophagus-Karzinoms ist das N-Staging von entscheidender Bedeutung. In der gaengigen radiologischen Literatur wird der MRT keine Bedeutung beim Staging des Oesophagus-Karzinoms zugeschrieben. Ursache hierfuer ist die meist unzureichende Abbildungsqualitaet der durch Atemexkursion und Herzpulsation erheblich betroffenen Mediastinalstrukturen. Der Einsatz von EKG-Gating in Kombination mit

  7. Accuracy of routine MRI in lesions of the supraspinatus tendon - comparison with surgical findings; Treffsicherheit der nativen und kontrastverstaerkten MRT im Routineeinsatz bei Supraspinatussehnenrupturen - Vergleich mit operativen Ergebnissen

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    Schroeder, R.-J.; Bostanjoglo, M.; Herzog, H.; Hidajat, N.; Roettgen, R.; Maeurer, J.; Felix, R. [Humboldt-Univ. zu Berlin, Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum (Germany); Kaeaeb, M. [Humboldt-Univ. zu Berlin, Klinik fuer Unfall- und Wiederherstellungschirurgie, Charite, Campus Virchow-Klinikum (Germany)

    2003-07-01

    degenerated tendons with partial rupture and complete rupture, and covered ruptures. (orig.) [German] Ziel: Korrelation des Laesionsausmasses der Supraspinatussehne im Schulter-MRT mit dem offen chirurgischen oder arthroskopischen Befund (chirurgische Klassifikation nach Snyders bzw. Bateman) bei Verwendung routinemaessig (Hauptfragestellung der Zuweiser: u.a. Rotatorenmanschettenlaesion posttraumatisch oder bei Bewegungseinschraenkung, Zustand des Labrum glenoidale) angefertigter MRT-Untersuchungen. Material und Methode: Retrospektiv verblindet wurden 80 (Patientenalter 16-76/47,4{+-}14,0 Jahre) zur Abklaerung unterschiedlicer Schulterbeschwerden praeoperativ durchgefuehrte MRT-Untersuchungen der Schulter von zwei unabhaengigen Auswertern analysiert. Evaluiert wurden hierbei das Vorliegen und Ausmass einer Supraspinatussehnenkomplett- oder -teilruptur. Anschliessend wurde bei diesen Patienten eine offene oder arthroskopische Operation durchgefuehrt, deren Befund als Goldstandard gewertet wurde. Verwendet wurden diverse MR-Tomographen mit Feldstaerken von 1,0 T (17 Faelle) bzw. 1,5 T (63 Faelle) sowie fuer Schulter- bzw. Gelenkuntersuchungen speziell geeignete starre oder flexible Spulen. Zusaetzlich zur Nativ-MRT wurde bei 38 von 80 Patienten intravenoes Kontrastmittel appliziert. Die von zwei Radiologen erstellten Befunde wurden mit den operativ bzw. arthroskopisch gewonnenen Ergebnissen verglichen und statistisch analysiert. Ergebnisse: Werden weder Lokalisation noch Ausdehnung der Kontinuitaetsstoerung der Supraspinatussehne beruecksichtigt, erbrachten die 80 MRT eine Sensitivitaet von 0,93, eine Spezifitaet von 0,69 und eine Treffsicherheit von 0,85. Die Sensitivitaet stieg auf 0,96 bei gleichbleibender Spezifitaet und einer Treffsicherheit von 0,83, wenn man die Laesionen von unter 1 cm Ausdehnung unberuecksichtigt liess. Vergleicht man die nativ und kontrastmittelgestuetzt durchgefuehrten mit den nur nativ durchgefuehrten MRT, lag bei jenen die Sensitivitaet um 7% (0

  8. Sensitivity of MRI in detecting alveolar infiltrates. Experimental studies; Sensitivitaet der MRT fuer alveolaere Infiltrate. Experimentelle Untersuchungen

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    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.)

  9. 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

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    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

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

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

    2004-07-01

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

  11. 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

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    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

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

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

    1992-08-01

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

  13. Iod(III)-katalysierte, direkte Umwandlung von Imiden zu beta-Lactamen und Derivaten und Design, Synthese und Evaluierung fluorhaltiger Verbindungen als Kontrastmittel für Anwendungen in der 19F-MRT

    OpenAIRE

    Patzelt, Christoph

    2016-01-01

    Die hier vorliegende Arbeit befasst sich im ersten Teil mit der Entwicklung einer Iod(III)-katalysierten, mehrstufigen Reaktionssequenz zur direkten Umwandlung von Imiden zu beta-Lactamen und entsprechenden Derivaten. Im zweiten Teil der Arbeit wurde eine Syntheseroute für fluorhaltige Polyethylenglykolderivate erarbeitet, nach der unterschiedlich fluorierte Verbindungen synthetisiert wurden und anschließend ihre Eignung als Kontrastmittel für Anwendungen in der 19F-MRT überprüft wurde. T...

  14. The contribution of MRI to the detection of endovascular aneurysm repair; Wertigkeit der MRT in der Erkennung von Leckagen nach endovaskulaerer Aneurysmaausschaltung

    Energy Technology Data Exchange (ETDEWEB)

    Kraemer, S.C.; Goerich, J.; Aschoff, A.J.; Wisianowski, C.; Brambs, H.J. [Ulm Univ. (Germany). Abt. fuer Diagnostische Radiologie; Pamler, R. [Ulm Univ. (Germany). Abt. fuer Gefaess- und Thoraxchirurgie

    2002-10-01

    inklusive MRA durchgefuehrt. Die vergleichende Auswertung von CT und MRT erfolgte retrospektiv durch zwei unabhaengige Befunder bezueglich Leckerkennung, Gefaessversorgung und Bildartefakte. Ergebnisse: Mittels Kernspintomographie konnten alle Leckagen erkannt werden (Typ 1 Leck: n=3, Typ II Leck: n=7), wobei der Spiral-CT ein Leck entging. MR-angiographisch liessen sich in 7 Faellen die zufuehrenden Gefaesse nachweisen gegenueber nur 1 Fall in der CT. Die Metallartefakte fielen in der MRT deutlich geringer aus, als in der CT. Eine statistisch signifikant bessere Darstellung war fuer das Leck sowie das speisende Gefaess in der MRA erreichbar. Die Spiral-CT war in einem Einzelfall nach vorausgegangener Embolisation aufgrund von erheblichen Ueberlagerungen durch Metallspiralen nicht diagnostisch verwertar. Schlussfolgerung: Die Kernspintomographie zeigt in der Darstellung von Leckagen nach endovaskulaerer Aneurysmaausschaltung gleich- bzw. hoeherwertige Ergebnisse als die Spiral-CT. Der Hauptvorteil liegt darueber hinaus in der artefaktreduzierten Abbildung sowie der fehlenden Strahlenbelastung. (orig.)

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

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    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

  16. Anatomy and pathology with the MRI of the parotid gland; Anatomie und Pathologie der Glandula parotis. Korrelation mit der Magnetresonanztomographie (MRT)

    Energy Technology Data Exchange (ETDEWEB)

    Sartoretti-Schefer, S. [Inst. fuer Neuroradiologie, Nordtrakt I, Universitaetsspital Zurich (Switzerland); Sartoretti, C. [Inst. fuer Neuroradiologie, Nordtrakt I, Universitaetsspital Zurich (Switzerland); Wichmann, W. [Inst. fuer Neuroradiologie, Nordtrakt I, Universitaetsspital Zurich (Switzerland); Valavanis, A. [Inst. fuer Neuroradiologie, Nordtrakt I, Universitaetsspital Zurich (Switzerland)

    1995-11-01

    MRI is an optimal tool for the delineation of the anatomy of the parotid gland and of various intraparotid lesions and often permits differentiation among malignant and benign neoplastic and inflammatory lesions. The morphology of the different pathological lesions on MRI reflects the underlying histopathology. Due to great interindividual variations in the tissue characterization of a specific intraparotid lesion, great differences in MR morphology have to be expected. (orig.) [Deutsch] Aufgrund des hohen oertlichen Aufloesungsvermoegens der MRT gelingt es, sowohl die Anatomie der Parotis und ihrer Umgebung als auch die einzelnen pathologischen Laesionen sehr zuverlaessig abzubilden. Die genaue topographische Beziehung einer Laesion zur Umgebung kann ebenso genau wie die Umgebungsinfiltration dargestellt werden. Eine Differenzierung zwischen benignen und malignen neoplastischen und entzuendlichen Laesionen ist oft, aber nicht immer moeglich. Abgesehen von wenigen Ausnahmen (v.a. beim pleomorphen Adenom) ist es aber bislang nicht moeglich, eine exakte Artdiagnostik einer spezifischen Parotislaesion zu stellen. Die sehr grossen interindividuellen histopathologischen Unterschiede der einzelnen Laesionen fuehren auch zu einer interindividuellen Vielfalt in der MR-Morphologie, widerspiegelt doch i.a. die MR-Morphologie die histologische Gewebezusammensetzung einer spezifischen Laesion. (orig.)

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

    Directory of Open Access Journals (Sweden)

    Y. Bakhshan

    2015-01-01

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

  18. Calculation of friction coefficient and analysis of fluid flow in a stepped micro-channel for wide range of Knudsen number using Lattice Boltzmann (MRT) method

    Science.gov (United States)

    Bakhshan, Younes; Omidvar, Alireza

    2015-12-01

    Micro scale gas flows have attracted significant research interest in the last two decades. In this research, the fluid flow of gases in a stepped micro-channel has been conducted. Wide range of Knudsen number has been implemented using the Lattice Boltzmann (MRT) method in this study. A modified second-order slip boundary condition and a Bosanquet-type effective viscosity are used to consider the velocity slip at the boundaries and to cover the slip and transition regimes of flow to obtain an accurate simulation of rarefied gases. The flow specifications such as pressure loss, velocity profile, stream lines and friction coefficient at different conditions have been presented. The results show, good agreement with available experimental data. The calculation shows, that the friction coefficient decreases with increasing the Knudsen number and stepping the micro-channel has an inverse effect on the friction coefficient value. Furthermore, a new correlation is suggested for calculation of the friction coefficient in the stepped micro-channel flows as below;

  19. Serial observations in Crohn`s disease: can hydro-MRI replace follow-through examinations?; Verlaufskontrolle des Morbus Crohn: Kann die Hydro-MRT die fraktionierte Magen-Darm-Passage ersetzen?

    Energy Technology Data Exchange (ETDEWEB)

    Schunk, K. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Metzmann, U. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Kersjes, W. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Schadmand-Fischer, S. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Kreitner, K.F. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Duchmann, R. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Protzer, U. [Mainz Univ. (Germany). 1. Medizinische Klinik und Poliklinik; Wanitschke, R. [Mainz Univ. (Germany). 1. Medizinische Klinik und Poliklinik; Thelen, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie

    1997-05-01

    To compare the value of hydro-MRI with follow-through examinations in the follow-up of Crohn`s disease. 22 patients known to be suffering from Crohn`s disease were examined via 1.5 T-MR system; an oral contrast examination using 1000 ml of a 2.5% mannitol solution was performed in all patients. T{sub 2}-weighted TSE sequences and T{sub 1}-weighted SE sequences were performed before and after the intravenous injection of Gd-DTPA. To reduce movement artifacts caused by peristalsis of the gut, intravenous injection of 40 mg Buscopan was given. The findings of hydro-MRI were compared with the follow-through examinations. In the upper gastrointestinal tract, the follow-through examination showed clear advantages compared with hydro-MRI for the demonstration of inflammatory changes in the gut; Hydro-MRI was, however, somewhat more reliable in the ileum and colon. It was also more sensitive than the follow-through for the demonstration of enteric fistulae (four as compared with two cases), and in demonstration extraluminal changes (free fluid in six against zero, and inflammatory adherent loops (four against zero)). Amongst the 22 patients, hydro-MRI was equal (in 10) or better (in 8) than the follow-through examination for demonstrating the intestinal manifestations of Crohn`s disease, and follow-through was better in only four. For follow-up of Crohn`s disease, hydro-MRI is at least as good as follow-through examination, and is even preferable, because of the absence of radiation exposure of the usually young patients. (orig.) [Deutsch] Die Aussagekraft der Hydro-Magnetresonanztomographie (Hydro-MRT) bei der Verlaufskontrolle eines M. Crohn sollte mit der der fraktionierten Magen-Darm-Passage (MDP) verglichen werden. 22 Patienten mit einem bekannten M. Crohn wurden an einem 1,5 T-MR-System untersucht; bei allen wurde eine orale Darmkontrastierung mit 1000 ml einer 2,5%igen Mannitolloesung durchgefuehrt. Zum Einsatz kamen T{sub 2}-gewichtete TSE-Sequenzen sowie T{sub 1

  20. 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

  1. 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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  4. Breathhold MRI of the small bowel in Crohn`s disease after enteroklysis with oral magnetic particles; Duenndarm-MRT mit schnellen MR-Sequenzen bei Morbus Crohn nach Enteroklysma mit oralen Eisenpartikeln

    Energy Technology Data Exchange (ETDEWEB)

    Holzknecht, N.; Helmberger, T.; Gauger, J.; Faber, S.; Reiser, M. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern, Ludwig-Maximilians-Univ. Muenchen (Germany); Ritter, C. von [Medizinische Klinik 2, Klinikum Grosshadern, Ludwig-Maximilians-Univ. Muenchen (Germany)

    1998-01-01

    Purpose: To evaluate the efficacy of breathhold MRI following enteroclysis with addition of oral magnetic particles to study the extension, detection of stenoses and extraluminal manifestations in Crohn`s disease. Results: Typical findings were marked bowel wall thickening with strong contrast enhancement. 95.8% of affected small bowel segments and 94.7% of stenoses were correctly detected by MRI. All four fistulas were detected and important extraluminal findings were seen in 6/18 patients. Additionally, one ileoileal and two ileosigmoidal adhesions, two extraluminal abscesses and affection of the right ureter were delineated. Conclusion: MRI in Crohn`s disease offers the potential to avoid radiation exposure in this relatively young patient group. Important additional findings relevant to indication of surgery are seen in approximately one third of cases. The replacement of transduodenal intubation by oral contrast application remains to be further studied. (orig./AJ) [Deutsch] Das Ziel dieser Arbeit war der Vergleich der diagnostischen Effizienz des konventionellen Duenndarmenteroklysmas mit anschliessender MRT mit negativem oralem Kontrastmittel bezueglich der Ausdehnung, Stenoseerkennung und relevanter Zusatzinformation bei Morbus Crohn. Im Vergleich mit dem Enteroklysma konnte die MRT-Untersuchung 95,8% der befallenden Segmente und 94,7% der Stenosen identifizieren. Alle 4 Fisteln wurden detektiert und zusaetzlich relevante Befunde in 6 von 18 Patienten gesehen (eine ileoileale und 2 ileosigmoidale Adhaesionen, 2 extraluminale Abzesse und ein entzuendlicher Pseudotumor mit Einbeziehung des rechten Ureters). Das Stenosegrading zeigte keine signifikanten Unterschiede (p=0,11). Zusaetzlich wurden extraluminal eine mesenteriale Lymphadenopathie (15/18) und mesenteriale Fettgewebsproliferation (12/18) mittels MRT nachgewiesen. (orig./AJ)

  5. Postoperative follow-up of Stanford type A aortic dissections with Spiral-CT and MRI: Normal imaging findings and typical complications; Spiral-CT und MRT der operierten Stanford Typ A-Aortendissektion: Verlauf und Komplikationen

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    Sommer, T.; Pauleit, D.; Hofer, U.; Preusse, K.; Layer, G.; Schild, H. [Bonn Univ. (Germany). Radiologische Klinik; Abu-Ramadan, D.; Likungu, J. [Bonn Univ. (Germany). Klinik fuer Herz- und Gefaesschirurgie

    1998-02-01

    Purpose: To demonstrate normal postoperative Spiral-CT and MRI findings and typical complications in patients with aortic repair after Stanford type A aortic dissection. Results: The following postoperative complications were seen: Three pseudoaneurysms which developed at the proximal anastomoses of the Dacron prosthesis in two cases and at the insertion site of the reimplanted left coronary artery after implantation of a composite graft (Bentall procedure) in one case; one re-dissection; one perforation of the false lumen; periprostethic flow in one patient after surgical repair of type A dissection by the graft inclusion technique; progressive dilatation of the false lumen in 4 cases; dilatation of the aortic root in a Marfan patient after replacement of the ascending aorta. Conclusion: Precise knowledge of the surgical technique performed is crucial to accurate postoperative imaging evaluation. MRI is the method of choice in the postoperative follow-up of clinically stable patients with aortic dissections. (orig./AJ) [Deutsch] Ziel: Darstellung der verschiedenen Operationsverfahren bei der Stanford Typ A-Dissektion mit ihren typischen Aspekten in Spiral-CT und MRT sowie ihren spezifischen Komplikationen. Ergebnisse: Folgende postoperative Komplikationen traten auf: Drei Pseudoaneurysmen, die zweimal von der proximalen Anastomose des Aorta-ascendens-Ersatzes sowie einmal von der Insertionsstelle der reimplantierten linken Koronararterie (Operation nach Bentall) ausgingen; eine Re-Dissektion; eine gedeckte Perforation des falschen Lumens; periprothetischer Fluss nach Anwendung der Graft-Inclusion-Technik; progrediente Dilatation des falschen Lumens in 4 Faellen; aneurysmatische Erweiterung des originaeren Aortenbulbus bei einem Marfan-Patienten nach suprakoronarem Aorta-ascendens-Ersatz. Schlussfolgerung: Bei der postoperativen Verlaufskontrolle von Patienten mit Aortendissektionen mittels Spiral-CT und MRT sind Kenntnisse der verschiedenen Operationsverfahren mit

  6. 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

  7. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Sartoretti-Schefer, S. [Inst. fuer Neuroradiologie, Universitaetsspital Zuerich (Switzerland); Wichmann, W. [Inst. fuer Neuroradiologie, Universitaetsspital Zuerich (Switzerland); Valavanis, A. [Inst. fuer Neuroradiologie, Universitaetsspital Zuerich (Switzerland)

    1996-11-01

    und immunkompetenten Patienten eingeteilt, was teilweise Rueckschluesse auf die zugrundeliegende Aetiologie erlaubt. Der immunsupprimierte Patient leidet vor allem an viralen (Herpes simplex, Herpes zoster, Zytomegalie, HIV-Virus) sowie an bakteriellen (Tuberkulose, selten Syphilis), aber nur selten an parasitaeren Infektionen. Der immunkompetente Patient erkrankt vor allem an bakteriellen Infektionen (Borreliose) sowie an immunologisch bedingten entzuendlichen Erkrankungen (Sarkoidose) und an demyelinisierenden Laesionen. Haeufig ist auch die idiopathische Myelitis. Virale Infektionen sind selten. Die MRT-Morphologie der entzuendlichen Laesionen wird durch sekundaere ischaemische und demyelinisierende Veraenderungen kompliziert, wodurch die Differentialdiagnose sehr erschwert sein kann, da das gesamte Spektrum von demyelinisierenden bzw. ischaemischen und entzuendlichen Erkrankungen miteinbezogen werden muss. Zudem koennen auch tumoroese Prozesse eine Myelitis bzw. Radikulitis nachahmen. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  10. Dynamic contrast-enhanced MRI for the evaluation of bone marrow microcirculation in hematologic malignancies before and during thalidomide therapy; Dynamische kontrastverstaerkte MRT zur Beurteilung der Knochenmarksmikrozirkulation bei malignen haematologischen Erkrankungen vor und waehrend einer Thalidomidtherapie

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, A.; Wittsack, H.J.; Engelbrecht, V.; Moedder, U. [Duesseldorf Univ. (Germany). Inst. fuer Diagnostische Radiologie; Strupp, C.; Germing, U.; Gattermann, N.; Haas, R. [Duesseldorf Univ. (Germany). Klinik fuer Haematologie, Onkologie und klinische Immunologie; Willers, R. [Duesseldorf Univ. (Germany). Universitaetsrechenzentrum

    2002-03-01

    Purpose. The aim of the study was to measure microcirculation parameters by dynamic contrast-enhanced MRI (d-MRI) and to evaluate the anti-angiogentic effects during treatment with thalidomide in different hematologic malignancies. Methods. In 20 healthy normal persons, 20 patients with myelodysplastic syndromes (MDS), 10 patients with multiple myeloma (MM) and 10 with myelofibrosis (MF) a fast gradient echo sequence (Turbo fast low angle shot 2D) with a pump controlled bolus infusion of gadolinium-DTPA was performed before and in 18 of these after beginning (average of 4,3 months) of a thalidomide therapy. Two pharmacokinetic parameters - the amplitude and exchange-rate-constant - were calculated and a statistical comparison of these values between healthy persons and patients as well as a correlation with the clinical course was executed. Results. Compared with the normal controls the patients showed a higher amplitude (normal persons 14.4{+-}5.2, MDS 24.8{+-}8.1, MF 35.9{+-}4.3, MM 23.4{+-}3.6) and exchange-rate-constant (normal persons 0.124{+-}0.042, MDS 0.136{+-}0.036, MF 0.144{+-}0.068, MM 0.131{+-}0.034). In the d-MRI-follow-up examinations a signficant (p<0.005) reduction of the amplitude and exchange rate constant values was evident in 14 of 18 patients undergoing a thalidomide therapy. Clinically all of these patients showed a therapy responding with complete or partial diseases remission. Conclusions. In patients with hematologic malignancies significantly higher d-MRI-microcirculation parameters of the lumbar spine can be demonstrated than in normal persons. During anti-angiogenetic treatment with thalidomide a decrease of these values was observed in case of a responding to therapy. (orig.) [German] Fragestellung. Unser Ziel war die Beurteilung der Mikrovaskularisation und des antiangiogenetischen Effektes einer Thalidomidtherapie mittels dynamischer kontrastverstaerkter MRT (d-MRT) bei unterschiedlichen haematologischen Erkrankungen. Methodik. Bei 20

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-02-15

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

  12. 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

    Energy Technology Data Exchange (ETDEWEB)

    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

  13. 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

  14. Initial results using MRI-guided laser-induced interstitial thermotherapy for head and neck tumors; Erste Ergebnisse der MRT-gesteuerten laserinduzierten interstitiellen Thermotherapie von Kopf- und Halstumoren

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, L. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Mueller-Lisse, G.U. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Gutmann, R. [Klinikum und Poliklinik fuer Hals-, Nasen- und Ohrenkranke, Klinikum Grasshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Feyh, J. [Klinikum und Poliklinik fuer Hals-, Nasen- und Ohrenkranke, Klinikum Grasshadern der Ludwig-Maximilians-Universitaet, Muenchen (Germany); Thoma, M. [Inst. fuer Radiologische Diagnostik, 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

    Laser-induced interstitial thermotherapy (LITT) was introduced as a minimally invasive form of therapy for tumors in different anatomic regions. However, in the orofacial region, it has not been used so far for inoperable T4 carcinomas. Since vascular and neural structures are often close to the tumor or are even involved, online monitoring of LITT is necessary. The aim of our study was to establish a method of monitoring LITT with MRI (magnetic resonance imaging) in the orofacial region. Five patients with T4 carcinomas of the orofacial region underwent LITT under anesthesia. A 1.5 T wholebody imager with a circulary polarized head coild was used. Before and after the intervention, the region of interest was studied using T1- and T2-weighted sequences in axial and coronal planes, with and without contrast enhancement (intravenous Gd-DTPA). Temperature distribution was monitored with a T1-weighted 2D-FLASH (fast low angle shot) sequence. The positioning of the optical fibers was monitored with MRI. Nd:YAG laser equipment was used for laser application. The necrosis was best seen on contrast-enhanced MRI. Immediately after LITT, the outcome could be determined by MRI. We proposed that MRI-guided LITT be used for neoplasma in the orofacial region at advanced stages. (orig.) [Deutsch] Als neues minimalinvasives Verfahren wird die laserinduzierte interstitielle Thermotherapie (LITT) zunehmend bei tumoroesen Raumforderungen eingesetzt. In der Therapie von ausgedehnten Tumoren der Orofazialregion liegen bisher keine Erfahrungen vor. Die anatomische Komplexitaet dieser Region mit eng benachbarten vaskulaeren und nervalen Strukturen, an die meist der Tumor reicht, erlaubt keine Eingriffe ohne eine kontinuierliche Ueberwachung. Ziel unserer Untersuchungen war die Etablierung einer LITT von ausgedehnten inoperablen Kopf- und Halstumoren unter MRT-(Magnetresonanztomographie-)Kontrolle. Die Untersuchungen wurden an einem 1,5-T-Ganzkoerpertomographen, unter Verwendung einer

  15. 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

  16. Lenin kontra Bogdanov : mõtteid Vene revolutsiooni filosoofilistest eeldustest / Jaan Undusk

    Index Scriptorium Estoniae

    Undusk, Jaan, 1958-

    2005-01-01

    V. I. Lenini filosoofilis-poliitilisest traktaadist "Materialism ja empiriokrititsism" (1909), mille tähtsus filosoofia ajaloos on marksistliku tunnetusteooria dogma e. leninliku peegeldusteooria väljatöötamine. Prantsuse filosoofide E. Machi, R. Avenariuse ja vene strukturalisti A. Bogdanovi filosoofia ning vene "empiriokriitiline" bolshevike koolkond

  17. Primary myelofibrosis (PMF), post polycythemia vera myelofibrosis (post-PV MF), post essential thrombocythemia myelofibrosis (post-ET MF), blast phase PMF (PMF-BP): Consensus on terminology by the international working group for myelofibrosis research and treatment (IWG-MRT).

    Science.gov (United States)

    Mesa, Ruben A; Verstovsek, Srdan; Cervantes, Francisco; Barosi, Giovanni; Reilly, John T; Dupriez, Brigitte; Levine, Ross; Le Bousse-Kerdiles, Marie-Caroline; Wadleigh, Martha; Campbell, Peter J; Silver, Richard T; Vannucchi, Alessandro M; Deeg, H Joachim; Gisslinger, Heinz; Thomas, Deborah; Odenike, Olatoyosi; Solberg, Lawrence A; Gotlib, Jason; Hexner, Elizabeth; Nimer, Stephen D; Kantarjian, Hagop; Orazi, Attilio; Vardiman, James W; Thiele, Juergen; Tefferi, Ayalew

    2007-06-01

    The International Working Group for Myelofibrosis Research and Treatment (IWG-MRT) is comprised of hematologists, hematopathologists, and laboratory scientists and its main goal is to provide a forum for scientific exchange and collaboration. During its first general meeting in April 2006, the IWG-MRT established uniform treatment response criteria for chronic idiopathic myelofibrosis (CIMF); also known as agnogenic myeloid metaplasia (AMM), myelofibrosis with myeloid metaplasia (MMM), and many other names in the hematologic literature. This document summarizes the proceedings from the second meeting of the IWG-MRT, in November 2006, where the group discussed and agreed to standardize the nomenclature referring to CIMF: (i) the term primary myelofibrosis (PMF) was chosen over several other designations including CIMF, AMM, and MMM, (ii) myelofibrosis that develops in the setting of either polycythemia vera (PV) or essential thrombocythemia (ET) will be referred to as post-PV MF and post-ET MF, respectively, and (iii) "leukemic" transformation will be recognized as blast phase disease (PMF-BP, post-PV/ET MF in blast phase).

  18. MR criteria for differentiation of 'pseudo tumourous' lesions from bone sarcomas of the extremities. MRT-Kriterien zur Differenzierung 'pseudotumoroeser' Laesionen von Knochensarkomen der Extremitaeten

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, K. (Technische Univ. Muenchen, Klinikum rechts der Isar, Inst. fuer Roentgendiagnostik (Germany)); Rechl, H. (Technische Univ. Muenchen, Klinikum rechts der Isar, Orthopaedische Klinik (Germany)); Daschner, H. (Technische Univ. Muenchen, Klinikum rechts der Isar, Inst. fuer Roentgendiagnostik (Germany)); Kutschker, C. (Technische Univ. Muenchen, Klinikum rechts der Isar, Inst. fuer Roentgendiagnostik (Germany))

    1993-05-01

    The MRT scans of 57 patients with Ewing or osteosarcomas and 34 patients with haematogenous osteomyelitis or periostitis/stress fractures were examined in order to determine whether a distinction between benign or malignant lesions is possible. Four criteria were evaluated: The margin of the bone marrow component; intensity and homogeneity of the T[sub 1]-weighted signal in the bone marrow; presence of an extraosseus structured soft tissue mass and/or soft tissue edema. It was found that central osteosarcomas and Ewing's sarcomas reduced signal intensity of the marrow to become muscle-isointense with a well defined margin. In acute haematogenous osteomyelitis and periostitis/stress fracture the marrow lesion was not sharply demarcated. In contrast to patients with bone sarcomas only one case of osteomyelitis showed an extrosseus structured soft tissue mass. On the basis of these findings we believe that acute haematogenous osteomyelitis can be distinguished with high degree of accuracy from Ewing's sarcoma and central osteosarcomas. (orig.)

  19. Whole-body magnetic resonance in localization of a compartment syndrome in a high-voltage injury – a case-report [Ganzkörper-MRT zur Lokalisation eines Kompartmentsyndroms beim Starkstromverletzten – ein Fallbericht

    Directory of Open Access Journals (Sweden)

    Reichert, Bert

    2011-12-01

    Full Text Available [english] An 18-year-old male is suffering from a high-voltage injury and within only few hours develops very high serum levels of creatine kinase as well as brown colored urine. This indicates a compartment syndrome, but it is not possible to find its exact location only by clinical means. Therefore we immediately performed a MRI of the whole body. The area damaged most intensely was found in the right thigh and therefore we performed limited fasciotomy there. The tissue recovered within a few minutes. 6 months later no functional impairments have remained.[german] Ein 18-jähriger Mann wird durch Einwirkung von Hochspannung schwer verletzt und entwickelt innerhalb weniger Stunden einen drastischen Anstieg der Creatrininkinase (CK sowie eine deutliche Verfärbung des Urins. Klinisch lässt sich das deswegen als sicher zu vermutende, aufgrund ödematöser Schwellung entstandene Kompartmentsyndrom allerdings nicht eindeutig lokalisieren, so dass eine notfallmäßige Ganzkörper-MRT erfolgt. Diese stellt als Zone der maximalen Muskelschädigung einen Abschnitt des rechten Oberschenkels hochsensitiv dar, so dass daraufhin eine Dekompression erfolgt, die auf diese Lokalisation beschränkt bleiben darf. Innerhalb weniger Minuten erholt sich das Muskelgewebe. Nach sechs Monaten sind keine funktionellen Residuen verblieben.

  20. 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.

  1. MR-guided laser-induced thermotherapy (LITT) of liver metastases. Prospective results of an optimized method; Laserinduzierte Thermotherapie (LITT) von Lebermetastasen unter MRT-Kontrolle. Prospektive Ergebnisse eines optimierten Therapieverfahrens

    Energy Technology Data Exchange (ETDEWEB)

    Vogl, T.J. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Mueller, P. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Hirsch, H. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Philipp, C. [Laser Medizin Zentrum, Freie Univ. Berlin (Germany); Hammerstingl, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Boettcher, H. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Riess, H. [Innere Klinik, Schwerpunkt Haematologie/Onkologie, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Beuthan, J. [Laser Medizin Zentrum, Freie Univ. Berlin (Germany); Felix, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany)

    1995-03-01

    .3.1994 wurden 17 Patienten (4 Frauen, 13 Maenner) mit insgesamt 29 Laesionen in 25 Sitzungen therapiert. Fuer die LITT unter MRT-Kontrolle wurde ein Neodymium-yttrium-aluminium-garnet-(Nd-YAG 1064 nm)Laser mit variablen Energien zwischen 3 und 7,5 W eingesetzt. Die MR-Bildgebung zur Thermometrie erfolgte mit speziellen T1-gewichteten MR-Terhmosequenzen (Turbo-FLASH, FLASH-2D), wobei ein Temperaturanstieg mit einem zunehmenden Signalverlust korreliert. Die LITT verursachte keine Frueh- oder Spaetkomplikationen. Die kontrastmittelverstaerkte dynamische MRT der Kontrollparameter zeigte bei optimalem Ansprechen ein hypointenses Areal im Applikationsbereich des Lasers, einer Nekrose entsprechend. Bei Laesionen kleiner gleich 20 mm konnte eine nahezu 100%ige Tumornekrose erzielt werden, bei Metastasen groesser 20 mm gelang die Erzielung einer grossen Tumornekrose nur bei 50%. Die Therapiekontrolle ueber einen Zeitraum von 6 Monaten zeigte ein deutlich besseres Ansprechen der Laesionen mit einem Durchmesser kleiner gleich 20 mm mit einer lokalen Kontrollrate von ueber 66%. Bei Laesionen groesser 20 mm Durchmesser konnte in dieser Pilotstudie lediglich eine Tumoransprechrate von 35% erzielt werden. (orig./MG)

  2. 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

  3. Rheumatoid arthritis of the atlanto-axial joint. Ascertainment of the inflammatory changes by means of CT MRI with contrast medium; Rheumatoide Arthritis des kraniozervikalen Uebergangs. Erfassung der entzuendlichen Veraenderungen mittels KM-gestuetzter CT und MRT

    Energy Technology Data Exchange (ETDEWEB)

    Neuhold, A. [Inst. fuer Bildgebende Diagnostik, KH Rudolfinerhaus, Wien (Austria); Czerny, C. [Inst. fuer Bildgebende Diagnostik, KH Rudolfinerhaus, Wien (Austria); Stiskal, M. [Zentralroentgeninstitut, KH Lainz (Austria); Boehm, G. [Inst. fuer Pathologische Anatomie, Univ. Wien (Austria); Smolen, J. [2. Medizinische Abt., KH Lainz (Austria)

    1994-12-01

    A total of 136 patients with rheumatoid arthritis underwent MRI with sagittal T1-weighted spin echo sequences before and after i.v. administration of Gd-DTPA and with a 15-min delay. In addition, T2-weighted gradient echo sequences were performed. Conventional radiographs, including tomography in sagittal and a.p. planes, were also taken of all patients; 51 were also examined by CT before and after i.v. administration on contrast medium and in addition with a 15-min delayed series. The signal intensities of MRI and the changes in density caused by contrast uptake on CT were examined visually and measured quantitatively. The inflammatory changes were classified in four phases by the MRI and CT findings and hostological results. A correlation (p<0.05) was found with the erythrocyte sedimentation rate. MRI was superior to CT in 10% of cases. A discrete effusion in the anterior junction was missed in 4 cases and a hypervascular panus formation in 1 case by CT. The CT was superior to the other methods in detecting bony lesions and calcifications in the atlantoedental region. (orig./VHE) [Deutsch] Bei 136 Patienten mit rheumatoider Arthritis (RA) wurden Nativroentgen, Magnetresonanztomographie (MRT) und in 51 Faellen eine Computertomographie (CT) des atlantoaxialen Gelenkes angefertigt bzw. durchgefuehrt. Das Signalverhalten der entzuendlichen Veraenderungen wurde auf T1-gewichteten (T1W) Spinecho- (SE) und T2-gewichteten Gradientenechosequenzen (GE) visuell befundet und die Signalintensitaetszunahmen nach intravenoeser Kontrastmittel (KM)-Applikation von Gadolinium-DTPA unter Heranziehung der T1W SE-Sequenzen quantitativ ausgewertet. Auch das KM-Aufnahmeverhalten der entzuendlichen Veraenderungen wurde mittels CT quantitativ untersucht. Durch die visuelle und quantitative Auswertung konnten die entzuendlichen Veraenderungen in 4 Stadien eingeteilt werden, welche mit der Blutsenkungsgeschwindigkeit (BSG) korrelierten (p<0,05). Die Magnetresonanztomographie war der

  4. 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)

  5. MRT fuel element inspection at Dounreay

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, J.

    1997-08-01

    To ensure that their production and inspection processes are performed in an acceptable manner, ie. auditable and traceable, the MTR Fuel Element Fabrication Plant at Dounreay operates to a documented quality system. This quality system, together with the fuel element manufacturing and inspection operations, has been independently certified to ISO9002-1987, EN29002-1987 and BS5750:Pt2:1987 by Lloyd`s Register Quality Assurance Limited (LRQA). This certification also provides dual accreditation to the relevant German, Dutch and Australian certification bodies. This paper briefly describes the quality system, together with the various inspection stages involved in the manufacture of MTR fuel elements at Dounreay.

  6. Introduction and Mission Response Team (MRT)

    Science.gov (United States)

    Pool, Sam

    2005-01-01

    On February 1, 2003 the Space Shuttle Columbia, returning to Earth with a crew of seven astronauts, disintegrated along a track extending from California to Louisiana. Observers on the ground filmed breakup of the spacecraft. Debris fell along a 567 statute mile track from Littlefield, Texas to Fort Polk, Louisiana; the largest ever recorded debris field. At the time of the accident the National Aeronautics and Space Administration (NASA) flight surgeon on-duty at the Mission Control Center (MCC) in Houston, Texas initiated the medical contingency response. The DOD surgeon at Patrick Air Force Base was notified, NASA medical personnel were recalled and the services of Armed Forces Institute of Pathology (AFIP) were requested. Subsequent to the accident the NASA flight surgeons that had supported the crew on orbit now provided medical support to the crewmember s families. Federal Emergency Management Agency (FEMA), the National Transportation Safety Board (NTSB), the Federal Bureau of Investigation (FBI) and numerous other federal, state and local agencies along with the citizens of Texas and Louisiana responded to the disaster. Search and recovery was managed from a Disaster Field Office (DFO) established in Lufkin, Texas. Mishap Investigation Team (MIT) medical operations were managed from Barksdale Air Force Base, Louisiana. Accident investigation teams (Columbia Accident Investigation Task Force (CAITF) and Columbia Accident Investigation Board (CAIB)) appointed immediately after the disaster included current and former authorities in space medicine. In August 2003, the CAIB concluded its investigation and released its findings in a report published in February 2004.

  7. Fog harvesting on the verge of economic competitiveness

    Science.gov (United States)

    Tiedemann, K. J.; Lummerich, A.

    2010-07-01

    Water scarcity is the bottleneck for agriculture and development of Peru’s coast and subject to aggravation due to climate change. Until present day, Peru’s coast in general and the Lima Metropolitan Area (LMA) in particular have enjoyed to a great extend the effect of the country’s high altitude glaciers that serve as a buffer for the capital’s water demand during the highland dry season. However, climate models predict the disappearance of this buffer system below 5.500 masl by 2015, leaving one of the driest places on earth with yet another decrease in freshwater supply (Zapata 2008). The deviation of water resources from the highlands has led already to allocation conflicts. Peru is in urgent need of new concepts for water management. Fog harvesting was introduced to South America in the 1980s and has since been implemented at various locations in North and Central America, Europe, Africa, Asia and Australia. The Standard Fog Collector (SFC) as described by Schemenauer and Cereceda (1994) has proven to be a successful instrument for this purpose. Apart from a number of small scale investigations, the design of the collector has barely been changed over the past three decades (e.g. Gioda et al. 1993). Within the framework of the presented project, financed primarily by the Global Exploration Fund of the National Geographic Society and Bayer AG, new fog collectors were designed at pilot and full scale. Best results in terms of simplicity of construction and water yield were obtained by a metal frame structure called Eiffel. While covering the same amount of space as an SFC and using the same Raschel 65% shadow net, the Eiffel collector harvested up to 2.650 liters of water within a frame of 8x4m compared to up to 600 liters of water harvested by a SFC at the same location. In combination with a simplified maintenance concept, our collectors present an economically competitive alternative to water supply by truck delivery in a region that is not likely to be connected to a centralized water supply system within the next two decades. At the given water price and a given location, we calculate a break-even point after 8-9 years following the investment.

  8. Lattelecom "deal of century" on verge of annulment

    Index Scriptorium Estoniae

    2007-01-01

    Läti majandusministri kohusetäitja Gaidis Berzins teatas Lattelecomi juhatuse esimehele Nils Melngailisele, et tema töölepingut ei pikendata. Asjaolu pidurdab Lattelecomi erastamist investeerimisfirmale Blackstone Group ja Lattelecomi töötajatele

  9. Amputation Totale de La Verge: A Propos de Trois Observations

    Directory of Open Access Journals (Sweden)

    Kimassoum Rimtebaye

    2015-03-01

    Conclusion: qu’elle soit d’origine criminelle ou psychogène, l’amputation totale du pénis est rarissime. Les conséquences sont urinaires, sexuelles et psychogènes. La prise en charge doit être multidisciplinaire.

  10. EU constitution on verge of collapse / Jitendra Joshi

    Index Scriptorium Estoniae

    Joshi, Jitendra

    2003-01-01

    EL-i välisministrite kohtumisel Napolis püüti leida lahendusi teravatele erimeelsustele põhiseaduslikus leppes ning jõuti ka põhimõttelisele konsensusele, et ühenduse iga riik peab olema Euroopa Komisjonis esindatud

  11. Amputation Totale de La Verge: A Propos de Trois Observations

    African Journals Online (AJOL)

    Kimassoum Rimtebaye

    Elle pose quatre problèmes: sexuel, urinaire, esthétique et psychia- trique. Lorsque l'extrémité distale est ... tionner le méat et à placer une sonde urinaire à demeure Charrière. 18. L'ablation de la sonde était faite le 14e jour .... pansement compressif, le temps nécessaire de réaliser un bilan préopératoire et requérir un avis ...

  12. Italian natural history museums on the verge of collapse?

    Science.gov (United States)

    Andreone, Franco; Bartolozzi, Luca; Boano, Giovanni; Boero, Ferdinando; Bologna, Marco A.; Bon, Mauro; Bressi, Nicola; Capula, Massimo; Casale, Achille; Casiraghi, Maurizio; Chiozzi, Giorgio; Delfino, Massimo; Doria, Giuliano; Durante, Antonio; Ferrari, Marco; Gippoliti, Spartaco; Lanzinger, Michele; Latella, Leonardo; Maio, Nicola; Marangoni, Carla; Mazzotti, Stefano; Minelli, Alessandro; Muscio, Giuseppe; Nicolosi, Paola; Pievani, Telmo; Razzetti, Edoardo; Sabella, Giorgio; Valle, Marco; Vomero, Vincenzo; Zilli, Alberto

    2014-01-01

    Abstract The Italian natural history museums are facing a critical situation, due to the progressive loss of scientific relevance, decreasing economic investments, and scarcity of personnel. This is extremely alarming, especially for ensuring the long-term preservation of the precious collections they host. Moreover, a commitment in fieldwork to increase scientific collections and concurrent taxonomic research are rarely considered priorities, while most of the activities are addressed to public events with political payoffs, such as exhibits, didactic meetings, expositions, and talks. This is possibly due to the absence of a national museum that would have better steered research activities and overall concepts for collection management. We here propose that Italian natural history museums collaborate to instate a “metamuseum”, by establishing a reciprocal interaction network aimed at sharing budgetary and technical resources, which would assure better coordination of common long-term goals and scientific activities. PMID:25709525

  13. Carcinome verruqeux de la verge | Beddouche | Pan African ...

    African Journals Online (AJOL)

    The pelvic IRM showed an important infiltration of the two corpora cavernosa and urethra. Biopsies revealed well-differentiated tumor with epithelial, papillomatous proliferation and hyperkeratosis with no cytonuclear anomalies. The patient underwent total penectomy with urinary diversion by perineal urethrostomy.

  14. Automutilation avec amputation de la verge chez des patients ...

    African Journals Online (AJOL)

    Les auteurs rapportent 2 cas d'automutilation avec dans un cas une plaie pénétrante de l'abdomen chez des patients schizophrènes. Mots Clés: Schizophrénie, Automutilation majeure, microchirurgie. Self-inflicted genital mutilation is a major self inflicted mutilation (MSM) and occurs rarely. Psychosis is a major factor of this ...

  15. Les amputations et autres traumatismes de la verge

    Directory of Open Access Journals (Sweden)

    Ibrahima Diabaté

    2017-12-01

    Conclusion: Dans notre institutions, les TrV sont rares, potentiellement graves, survenant électivement chez des enfants et adolescents à la suite d’accidents domestique et de sport. Leur prise en charge thérapeutique ne pose pas de grandes difficultés dans les cas simples, en revanche le traitement des formes graves (amputations, fistules demeure un défi.

  16. 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

  17. Value of 13-MHz high-frequency ultrasound of the lateral ankle ligaments and the anterior tibiofibular ligament; 13-MHz-Hochfrequenzsonographie der lateralen Baender des oberen Sprunggelenkes einschliesslich der ventralen Syndesmose. Ein Vergleich mit den Ergebnissen der MRT bei 64 Patienten

    Energy Technology Data Exchange (ETDEWEB)

    Milz, P.; Steinborn, M.; Reiser, M. [Muenchen Univ. (Germany). Inst. fuer Radiologische Diagnostik; Milz, S. [Muenchen Univ. (Germany). Anatomische Anstalt; Mittlmeier, T. [Unfall- und Wiederherstellungschirurgie, Virchow-Klinikum, Humbolt-Univ. Berlin (Germany)

    1999-01-01

    Purpose: Determination of the value of 13-MHz high-frequency ultrasound in the diagnosis of acute injuries of the lateral ankle ligaments and the anterior tibiofibular ligament by comparison with MRI. Method: Sonography was performed prospectively in 64 acutely injured patients using a mechanical 13-MHz sector probe; for diagnosis of the anterior tibiofibular ligament a 15-MHz sector probe was employed during the course of this trial. Using a 0.2-T unit for MRI examination, T1-weighted (TR 580 ms, TE 24 ms) and T2-weighted (TR 3000 ms, TE 80 ms) spin-echo sequences were obtained in various oblique axial imaging planes. Results: In the differentiation of intact and injured ligaments, ultrasound and MRI agreed in 95.3/% of cases for the anterior fibulotalar ligament, in 88.3% for the fibulocalcanear ligament and in 85.0% for the anterior tibiofibular ligament. Conclusion: Lesions of the anterior talofibular and fibulocalcanear ligament can be accurately demonstrated by ultrasound if a 13-MHz sector scanner is used. The detection of lesions in the anterior tibiofibular ligament is more difficult. With increasing experience and by using a 15-MHz sector scanner, better results can be expected for this ligament. (orig.) [Deutsch] Fragestellung: Durch einen Vergleich mit den Befunden der MRT sollte die Aussagekraft der hochaufloesenden 13-MHz-Sonographie in der Diagnostik von akuten Verletzungen des Aussenbandapparates des Sprunggelenkes und der Syndesmose ueberprueft werden. Methodik: 64 akut verletzte Patienten wurden prospektiv mit einem mechanischen 13-MHz-Sektorscanner untersucht. Zur Beurteilung des Lig.tibiofibulare anterius wurde ergaenzend ein 15-MHz-Sektorscanner verwendet. Alle MRT wurden an einem 0,2-Tesla-Niederfeldgeraet durchgefuehrt. In unterschiedlichen schraeg axialen Schichtkippungen wurden T1-gewichtete SE-Sequenzen (TR 580 ms, TE 24 ms) und T2-gewichtete SE-Sequenzen (TR 3000 ms, TE 80 ms) angefertigt. Ergebnisse: Bei der Differenzierung intakter und

  18. Quantitative analysis of spinal CSF dynamics using magnetic resonance imaging: experimental and clinical studies; MR-tomographische Liquorflussmessungen am Spinalkanal mit einem optimierten MRT-Protokoll: experimentelle und klinische Untersuchungen

    Energy Technology Data Exchange (ETDEWEB)

    Freund, M.; Adwan, M.; Heiland, S.; Haehnel, S.; Sartor, K. [Neurologische Universitaetsklinik Heidelberg (Germany). Abt. Neuroradiologie; Kooijman, H. [Philips Medizin Systeme Unternehmensbereich der Philips GmbH, Hamburg (Germany); Thomsen, M. [Abt. Orthopaedie I der Stiftung Orthopaedische Universitaetsklinik Heidelberg (Germany); Jensen, K. [Universitaetsklinik Heidelberg (Germany). Inst. fuer Medizinische Biometrie und Informatik; Gerner, H.J. [Abt. Orthopaedie II der Stiftung Orthopaedische Universitaetsklinik Heidelberg (Germany)

    2001-04-01

    .66 ml/s) in the TSC and in the LSC 0.08 ml/s and 0.67 ml/s (mean: 0.29 ml/s). The results of the flow model studies showed an increase of velocity between 2.06 and 4.94 cm/s (mean: 3.31 cm/s) at the stenosis and 1.1 and 1.33 cm/s (mean: 1.23 cm/s) at a distance of 70 cm. (orig.) [German] Ziel: Messungen der zervikalen, thorakalen und lumbalen Liquordynamik mit der MRT und Messungen zur Ermittlung stenoseinduzierter Aenderungen der Flussdynamik mittels eines Flussmodells. Methoden: 68 gesunde Probanden und 4 Patienten wurden in drei Phasen untersucht. Phase I: 19 Probanden zur Sequenzoptimierung mit je 4 Messungen (4, 8, 12, 16 cm/s Flusssensitivitaet). Phase II: 49 Probanden wurden mit der optimierten Phasenkontrastsequenz untersucht. In der fortlaufenden Phase III werden Patienten mit posttraumatischer Syrinx (PTS) untersucht. Bestimmt wurden max. Geschwindigkeiten (cm/s), Schlagvolumina (ml/s) sowie die Flaechen der zur Berechnung verwendeten ROI (mm{sup 2}). Im Flussmodell wurde das Lumen des zufuehrenden Schlauchschenkels 5-stufig komprimiert, die Geschwindigkeiten in Hoehe der Stenose und in 70 cm Entfernung gemessen und die Veraenderungen berechnet. Ergebnisse: 226 Messungen wurden durchgefuehrt. Phase I: 76 Messungen (62=81,5% verwertbar) zervikal, thorakal und lumbal. Optimal (gutes SNR-Verhaeltnis und gute Flusskurve, kein Aliasing) waren Flusssensitivitaeten von 12 cm/s zervikal, 6 cm/s thorakal und lumbal. Phase II: Es wurden 150 Messungen durchgefuehrt. 52 Messungen (16 zervikal, 24 thorakal, 12 lumbal) waren technisch hervorragend (34,6%). Zervikal fanden wir mit 0,95 cm/s die hoechste Geschwindigkeit in kraniokaudaler Richtung und mit 0,38 cm/s in kaudokranialer Richtung. Thorakal lag die Geschwindigkeit bei 4,7 cm/s bzw. 1,65 cm/s und lumbal bei 0,93 cm/s bzw. 0,59 cm/s. Die hoechsten Geschwindigkeiten wurden somit im thorakelen Spinalkanal sowohl in kraniokaudaler Richtung als auch in kaudokranialer Richtung gemessen. In Phase III lagen die maximalen

  19. MR imaging of muscle injuries; MRT von Muskelverletzungen

    Energy Technology Data Exchange (ETDEWEB)

    Woertler, Klaus [Technische Univ. Muenchen, Klinikum rechts der Isar (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie

    2014-12-15

    Injuries to skeletal muscle are very common particularly in athletes. Besides ultrasound, MR imaging represents the most valuable imaging modality for diagnosis and grading of muscle lesions. This article reviews the examination technique and diagnostic criteria of acute and chronic lesions of skeletal muscle at MR imaging. In addition to the morphology of direct and indirect muscle injuries, MR findings in myositis ossificans and compartment syndrome are discussed as well.

  20. MRI of aneurysmal bone cyst. MRT der aneurysmalen Knochenzyste

    Energy Technology Data Exchange (ETDEWEB)

    Sigmund, G.; Vinee, P.; Geissler, A.; Wimmer, B. (Freiburg Univ. (Germany). Radiologische Universitaetsklinik); Dosch, J.C. (Centre de Traumatologie et d' Orthopedie, 67 - Illkirch-Graffenstaden (France). Service de Radiologie); Adler, C.P. (Freiburg Univ. (Germany). Referenzzentrum fuer Knochenkrankheiten)

    1991-10-01

    The preoperative findings of magnetic resonance imaging (MRI) in six histology-proven aneurysmal bone cysts (ABC) are examined and compared with previous publications concerning MRI of ABC. The signal intensities differ considerably, and not all of our cases conform with the literature data. They can be summarised in three different subheadings: one form that is very inhomogeneous in T{sub 1}- and T{sub 2}-weighting, with fluid-fluid levels in the cystic spaces; one intermediate form without fluid-fluid levels, which is inhomogeneous only in T{sub 2}-weighted images; and finally, an unusual form of ABC has homogeneous low signal both in T{sub 1}- and T{sub 2}-weighting, and which has not been described in literature so far. (orig.).

  1. Atrial tumors in cardiac MRI; Vorhoftumoren in der kardialen MRT

    Energy Technology Data Exchange (ETDEWEB)

    Kraemer, Nils; Schoth, F.; Guenther, R.W.; Krombach, G. [Klinik fuer Radiologische Diagnostik, Universitaetsklinikum RWTH Aachen (Germany); Balzer, J.C.; Neizel, M.; Kuehl, H. [Klinik fuer Kardiologie, Pneumologie und Angiologie, Universitaetsklinikum RWTH Aachen (Germany)

    2009-11-15

    Cardiac magnetic resonance imaging (MRI) is an important tool for the diagnosis of cardiac masses. Various cardiac tumors are predisposed to occurring in atrial structures. The aim of this review article is the description of atrial tumors and their morphological features in MRI. In general, cardiac tumors are rare: approximately 0.001-0.03% in autopsy studies. About 75% of them are benign. The most common cardiac tumor is the myxoma. They are predisposed to occur in the atria and show a characteristically strong hyperintense signal on T2-wieghted images in MRI. In other sequences a heterogeneous pattern reflects its variable histological appearance. Lipomas exhibit a signal behavior identical to fatty tissue with a typical passive movement in cine imaging. Fibroelastomas are the most common tumors of the cardiac valves. Consisting of avascular fibrous tissue, they often present with hypointense signal intensities. Thrombi attached to their surface can cause severe emboli even in small tumors. Amongst primary cardiac malignancies, sarcomas are most common and favor the atria. Secondary malignancies of the heart are far more common than primary ones (20-40 times). In case of known malignancies, approximately 10% of patients develop cardiac metastasis at the end of their disease. Lymphogenic metastases favor the pericardium, while hematogenic spread prefers the myocardium. Since they are not real atrial tumors, thrombi and anatomical structures of the atria have to be differentiated from other pathologies. (orig.)

  2. Magnetic resonance imaging in children; MRT-Untersuchungen bei Kindern

    Energy Technology Data Exchange (ETDEWEB)

    Moritz, Joerg D. [UKSH Campus Kiel (Germany). Klinik fuer diagnostische Radiologie, Paediatrische Radiologie und Sonografie

    2009-06-15

    Magnetic resonance imaging (MRI) is behind ultrasound the most important sectional imaging modality in children and adolescents. Owing to newer techniques it is used for multiple indications in nearly all regions and organs. This article describes the special features in the performance of MRI examinations in children. Different forms of sedation as well as adequate preparation and monitoring are explained. Moreover methods are discussed, which enable an examination of unsedated children. Special requirements on MRI machines and coils to be chosen are explained. One chapter discusses special sequences and techniques of respiration gating, which are used with priority in children. Special aspects of parenteral and oral contrast mediums are explained. Finally a summary is given of distinct indications and examination protocols for different regions and organs. (orig.)

  3. 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.)

  4. 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.

  5. 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.

  6. Multiplex real-time PCR (MRT-PCR) for diarrheagenic.

    Science.gov (United States)

    Barletta, Francesca; Ochoa, Theresa J; Cleary, Thomas G

    2013-01-01

    Diarrheagenic Escherichia coli strains are important causes of diarrhea in children from the developing world and are now being recognized as emerging enteropathogens in the developed world. Current methods of detection are too expensive and labor-intensive for routine detection of these organisms to be practical. We developed a real-time fluorescence-based multiplex PCR for the detection of all six of the currently recognized classes of diarrheagenic E. coli. The primers were designed to specifically amplify eight different virulence genes in the same reaction: aggR for enteroaggregative E. coli (EAEC), stIa/stIb and lt for enterotoxigenic E. coli (ETEC), eaeA for enteropathogenic E. coli (EPEC), stx1 and stx2 for Shiga toxin-producing E. coli (STEC), ipaH for enteroinvasive E. coli (EIEC), and daaD for diffusely adherent E. coli (DAEC).

  7. MRT letter: Expression of ATP sensor protein in Caenorhabditis elegans.

    Science.gov (United States)

    Kishikawa, Jun-ichi; Fujikawa, Makoto; Imamura, Hiromi; Yasuda, Kayo; Noji, Hiroyuki; Ishii, Naoaki; Mitani, Shohei; Yokoyama, Ken

    2012-01-01

    Adenosine 5'-triphosphate (ATP) is the major energy currency and is involved in many biological processes. The ATP-monitoring system for cells in animals can be helpful to study the relationship between energy metabolism and biological processes. The fluorescent ATP biosensor ATeam (ATP indicator based on Epsilon subunit for Analytical Measurements), which has been reported to monitor ATP levels in cultured cells on the basis of fluorescence resonance energy transfer (FRET), was introduced into nematodes by microinjection and UV-irradiation method. To confirm whether ATeam functions as an ATP sensor in nematode cells, the authors measured FRET of ATeam in cells of transgenic nematode. The ATeam was expressed in target cells in nematode. In vulva cells, ATP levels in the cytosol were higher than those in mitochondria. ATeam also sensed ATP level change in cultured cells from the transgenic nematode. These experiments indicated that ATeam is available for detection of changes in ATP levels in nematode cells. Copyright © 2011 Wiley Periodicals, Inc.

  8. Improving MRT image quality in patients with movement disorders.

    Science.gov (United States)

    Schültke, Elisabeth; Nanko, Norbert; Pinsker, Marcus; Katzev, Michael; Sebastian, Alexandra; Feige, Bernd; Nikkhah, Guido

    2013-01-01

    In order to improve image quality in a simultaneous fMRI-EEG study with patients suffering from the involuntary movements typical for Huntington's disease, the aim was to develop a technique for immobilizing the heads of our patients inside an MRI head coil. We modified a mask technique previously used for reliable repositioning in temporally fractionated radiotherapy. The mask was tested in three patients with Huntington's disease, acquiring structural and functional MR images with simultaneous EEG with and without the mask. Image as well as EEG signal quality were significantly improved in patients wearing the mask. However, the image quality with mask was comparable to acquisitions from patients without movement disorders only in patients with light to moderate dyskinesia. Although image quality was also significantly improved in a patient suffering from severe dyskinesia with quasi-continuous involuntary movements, the quality of both the MR images as well as the EEG signal was lower than what would be expected in a healthy control person. We have succeeded in developing a mask that fits into the MRI head coil, does not disturb the MRI signal, and significantly improves both fMRI and EEG signal quality.

  9. [Combination of TMS and MRT to understand neurological diseases].

    Science.gov (United States)

    Hummel, F C

    2014-06-01

    Modern neuroimaging techniques, such as structural and functional magnetic resonance imaging (MRI) and non-invasive brain stimulation techniques, such as transcranial magnetic stimulation (TMS) are increasingly used in the neuroscientific research of neurological disorders, such as stroke, tinnitus and movement disorders. These methods offer a non-invasive approach and especially in combination, not only the opportunity to add to the pathophysiological understanding of these disorders but also to provide information about the functional recovery and the natural course of the disease in a predictive way. Based on such knowledge therapeutic approaches can be adapted in a patient-tailored fashion to achieve the best therapeutic effects. Furthermore, these methods might provide additional non-invasive information for neurosurgical interventions reducing perioperative interventional risks.In the present article these aspects will be discussed with a focus on the combination of MRI and TMS especially addressed for the topic of recovery from stroke.

  10. MRT letter: recovering weak-textured surfaces using image focus.

    Science.gov (United States)

    Muhammad, Mannan Saeed; Choi, Tae-Sun

    2009-10-01

    In nature, objects have partially weak texture and their shape reconstruction using focus based passive methods like shape from focus (SFF), is difficult. This article presents a new SFF algorithm which can compute precise depth of dense as well as weak textured objects. Segmentation is applied to discard wrong depth estimate and then later interpolating them from accurate depth values of their neighbors. The performance of the proposed method is tested, using different image sequences of synthetic and real objects, with varying textures.

  11. MRT letter: visual attention driven framework for hysteroscopy video abstraction.

    Science.gov (United States)

    Ejaz, Naveed; Mehmood, Irfan; Baik, Sung Wook

    2013-06-01

    Diagnostic hysteroscopy is a popular method for investigating the regions in the female reproductive system. The videos generated by hysteroscopy sessions of patients are recurrently archived in medical libraries. Gynecologists often need to browse these libraries in search of similar cases or for reviewing old videos of a patient. Diagnostic hysteroscopy videos contain a lot of information with abundant redundancy. Key frame extraction-based video summarization can be used to reduce this huge amount of data. Moreover, key frames can be used for browsing and indexing of hysteroscopy videos. In this article, a domain specific visual attention driven framework for summarization of hysteroscopy videos is proposed. The visual attention model is materialized by computing saliency based on color, texture, and motion. The experimental results, in comparison with other techniques, demonstrate the efficacy of the proposed framework. Copyright © 2013 Wiley Periodicals, Inc.

  12. Differential diagnosis of focal lesions of the kidney in CT and MRT; Differentialdiagnose fokaler Nierenlaesionen in CT und MRT

    Energy Technology Data Exchange (ETDEWEB)

    Heckmann, M.; Heinrich, M.; Bautz, W.; Uder, M. [Universitaetsklinikum Erlangen (Germany). Radiologisches Inst.; Humke, U. [Katharinenhospital Stuttgart (Germany). Urologische Klinik

    2008-07-01

    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.)

  13. 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.)

  14. Communities on the Verge: Intersections and Disjunctures in the New Information Order.

    Science.gov (United States)

    Tu, Thuy Linh; Rush, Debra Wexler; Hines, Alicia Headlam; Nelson, Alondra

    1997-01-01

    Examines the relationship of information technology to communities of color. Argues that attempts to "stake a claim in cyberspace" happen on two levels: the "virtual" and the "real." Explores questions of how community is imagined by people of color using icons and language, and how images and language mark insiders and outsiders. Notes…

  15. Synthetic Organic Electrochemical Methods Since 2000: On the Verge of a Renaissance.

    Science.gov (United States)

    Yan, Ming; Kawamata, Yu; Baran, Phil S

    2017-11-08

    Electrochemistry represents one of the most intimate ways of interacting with molecules. This review discusses advances in synthetic organic electrochemistry since 2000. Enabling methods and synthetic applications are analyzed alongside innate advantages as well as future challenges of electroorganic chemistry.

  16. Not only the butterflies: managing ants on road verges to benefit Phengaris (Maculinea) butterflies

    NARCIS (Netherlands)

    Wynhoff, I.; Gestel, van R.; Swaay, van C.; Langevelde, van F.

    2011-01-01

    Obligate myrmecophilic butterfly species, such as Phengaris (Maculinea) teleius and P. nausithous, have narrow habitat requirements. Living as a caterpillar in the nests of the ant species Myrmica scabrinodis and M. rubra, respectively, they can only survive on sites with both host ants and the host

  17. "On the Verge of a Renaissance": Arkansas Schools, Curricula, and Teachers during the Great Depression

    Science.gov (United States)

    Field, Sherry L.; Bauml, Michelle; Bellows, M. Elizabeth

    2014-01-01

    This article is the third in a larger study of schooling during the Great Depression that seeks to elucidate specific examples of elementary social studies teaching and learning in the South during this time, particularly in Arkansas. Responding to Christine Woyshner's (2009) concern that histories of social studies should look beyond national…

  18. The importance of roads and road verges for raptors and crows in ...

    African Journals Online (AJOL)

    The behaviour and activities of 6 458 raptors (Accipitridae and Falconidae) and 1 947 Corvidae in the Karoo, South Africa, were recorded during the period January 1988 to June 2000 (n = 208 surveys) over a total distance of 90 012km. A significantly larger proportion of raptors and corvids were recorded foraging in road ...

  19. Country on the verge of an AIDS epidemic. Russia, education (health).

    Science.gov (United States)

    1997-06-30

    This news brief indicates that HIV infections in Russia could rapidly increase from a few thousand currently to almost 800,000 by the year 2000. The Kremlin initiated an advertising campaign targeting 15-24 year olds with a message of safe sex. Health authorities are accepting the help of Medecins sans Frontieres (Doctors without Borders). The group will adapt strategies that were successful abroad to local Russian conditions. About 76% of HIV-infected persons are intravenous drug users. There is the potential for the spread of HIV heterosexually. Already, syphilis infections have increased by 60 times over the past 8 years. Syphilis cases increased from around zero in 1988 to almost 400,000 at present. HIV infections have spread rapidly in Kaliningrad, which is a port city and a crossroads for the drug trade. Medecins sans Frontieres is targeting education programs to young drug users and training programs to medical workers. Television spots, music, billboards, bus signs, and the press are being used to spread the message about using condoms to prevent HIV and other sexually transmitted diseases. The task of health education and behavior change will be difficult in a country where most people have unhealthy life styles of smoking, alcohol drinking, and non-use of seatbelts. People are well informed about the dangers of AIDS, but people do not adopt health-protective behavior. At present, foreign condom makers dominate the market and are the ones most likely to benefit from the campaign. Russian condom producers have not shifted production from the heavy-duty Soviet era condoms that are referred to as "galoshes" to thin Western-style condoms. The number of new cases in 1996 exceeded the total number of cases in the preceding 9 years. By May 1997 there were 4494 HIV-infected persons, of whom 259 had full-blown AIDS.

  20. Possible extinction vortex for a population of Iberian lynx on the verge of extirpation.

    Science.gov (United States)

    Palomares, Francisco; Godoy, José Antonio; López-Bao, José Vicente; Rodríguez, Alejandro; Roques, Severine; Casas-Marce, Mireia; Revilla, Eloy; Delibes, Miguel

    2012-08-01

    Theory suggests that demographic and genetic traits deteriorate (i.e., fitness and genetic diversity decrease) when populations become small, and that such deterioration could precipitate positive feedback loops called extinction vortices. We examined whether demographic attributes and genetic traits have changed over time in one of the 2 remaining small populations of the highly endangered Iberian lynx (Lynx pardinus) in Doñana, Spain. From 1983 to 2008, we recorded nontraumatic mortality rates, litter size, offspring survival, age at territory acquisition, and sex ratio. We combined these demographic attributes with measures of inbreeding and genetic diversity at neutral loci (microsatellites) and genes subjected to selection (major histocompatibility complex). Data on demographic traits were obtained through capture and radio tracking, checking dens during breeding, track surveys, and camera trapping. For genetic analyses, we obtained blood or tissue samples from captured or necropsied individuals or from museum specimens. Over time a female-biased sex ratio developed, age of territory acquisition decreased, mean litter size decreased, and rates of nontraumatic mortality increased, but there were no significant changes in overall mortality rates, standardized individual heterozygosity declined steadily, and allelic diversity of exon 2 of class II major histocompatibility complex DRB genes remained constant (2 allelic variants present in all individuals analyzed). Changes in sex ratio and age of territory acquisition may have resulted from demographic stochasticity, whereas changes in litter size and nontraumatic mortality may be related to observed increases in inbreeding. Concomitant deterioration of both demographic attributes and genetic traits is consistent with an extinction vortex. The co-occurrence, with or without interaction, of demographic and genetic deterioration may explain the lack of success of conservation efforts with the Doñana population of Iberian lynx. ©2012 Society for Conservation Biology.

  1. Epigenetic Editing : On the Verge of Reprogramming Gene Expression at Will

    NARCIS (Netherlands)

    Cano-Rodriguez, David; Rots, Marianne G

    2016-01-01

    Genome targeting has quickly developed as one of the most promising fields in science. By using programmable DNA-binding platforms and nucleases, scientists are now able to accurately edit the genome. These DNA-binding tools have recently also been applied to engineer the epigenome for gene

  2. Moral attitudes towards doping – what do athletes on the verge of maturity value?

    Directory of Open Access Journals (Sweden)

    H Mroczkowska

    2009-09-01

    Full Text Available The aim of the present study was twofold: a to verify the previously detected regularities in a group of subjects larger than the one employed in a pilot study, and b to define the internal structure of the hierarchy of values that can be squandered as a result of doping. For the study, eighty-nine 16-18-year-old students from the fencing, athletics, martial arts, and football classes of the School of Championship in Sports were recruited. Experimental technique developed by Mroczkowska called “Perception of the risk of doping” was employed to individually rank the highly regarded values (e.g., health, medals won, physical appeal, mental balance, financial bonuses, and social respect that can be lost as a consequence of the use of illegal stimulants. It appears that young athletes would declaratively resign themselves from the loss of a financial bonus rather than from the loss of the social respect and attributes of self-integrity, such as physical and mental health. The detected correlations suggest that the rewarding value of a medal has an internal dimension: it externalizes a sense of self-confidence and confirms high self-esteem. The results indicate that, as perceived by the young, winning a medal with the help of doping is an illusion that does not allow to verify one’s own skills and limitations.

  3. The Black of Strei – a Swine Population on the Verge of Extinction in Banat

    Directory of Open Access Journals (Sweden)

    Marcel Matiuti

    2011-05-01

    Full Text Available The Black of Strei swine was declared to be extinct in 1974, but research conducted in 2008-2010 proved that there are still 61 specimens (Black of Strei proper and hybrids in the Hatzeg county and in the Lugoj area. Body measurements have been made in the case of those specimens and they showed that the specimens are a morphoproductive type. The local people appreciate the Black of Strei especially for its fat and bard which are very dry and used in order to obtain the traditional food products in the area. Prolificacy of sows farrowing is an 8 piglets per gestation. This breed is best kept in organic farms. The Black of Strei females are usually cross-bred with wildboar (Sus scrofa ferus males, the hybrids’ meat being very appreciated.

  4. High attack rate for malaria through irregular migration routes to a country on verge of elimination.

    Science.gov (United States)

    Wickramage, Kolitha; Premaratne, Risintha G; Peiris, Sharika L; Mosca, Davide

    2013-08-06

    Irregular migration in the form of human smuggling and human trafficking is recognized as a global public health issue. Thirty-two cases of Plasmodium falciparum were detected in 534 irregular migrants returning to Sri Lanka via failed human smuggling routes from West Africa in 2012, contributing to the largest burden of imported cases in Sri Lanka as it entered elimination phase. Beyond the criminality and human rights abuse, irregular migration plays an important, but often forgotten, pathway for malaria re-introduction. Active surveillance of the growing numbers of irregular migrant flows becomes an important strategy as Sri Lanka advances towards goals of malaria elimination.

  5. Prise en charge des fractures de verge. A propos de 30 cas ...

    African Journals Online (AJOL)

    Mot clés: fracture des corps caverneux, chirurgie, pénis traumatisme. Management of Penile Fracture Objectives: To evaluate our experience with the management of penile fractures. Patients and Methods: We retrospectively studied 30 cases of trauma to the erect penis seen at the Urology Department of Mohammed VI ...

  6. Mapping brain activity on the verge of a photically induced generalized tonic-clonic seizure

    DEFF Research Database (Denmark)

    Moeller, Friederike; Siebner, Hartwig R; Wolff, Stephan

    2009-01-01

    In a photosensitive patient intermittent photic stimulation (IPS) accidentally provoked a generalized tonic-clonic seizure during simultaneous recordings of electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). Before seizure onset, IPS consistently induced generalized ph...

  7. Is South Africa on the verge of a medical malpractice litigation storm ...

    African Journals Online (AJOL)

    South Africa is witnessing a sharp increase in medical malpractice litigation as patients increasingly become aware of their rights in a setting of an overburdened health system with limited resources. Legitimate claims need to be compensated. However, the consequences of increased litigation are: (i) a further reduction in ...

  8. Prise en charge diagnostique et thérapeutique des tumeurs de verge

    African Journals Online (AJOL)

    Squamous cell carcinoma of the penis is rare, representing less than 1% of all adult cancers. The etiology of this cancer is still unknown, but many risk factors have been suggested, above all the human papilloma virus. The authors describe two cases of infiltrating penile tumors. The first patient presented with a glandular ...

  9. P2Y12 Receptor on the Verge of a Neuroinflammatory Breakdown

    Directory of Open Access Journals (Sweden)

    Susanna Amadio

    2014-01-01

    Full Text Available In the CNS, neuroinflammation occurring during pathologies as amyotrophic lateral sclerosis (ALS and multiple sclerosis (MS is the consequence of an intricate interplay orchestrated by various cell phenotypes. Among the molecular cues having a role in this process, extracellular nucleotides are responsible for intercellular communication and propagation of inflammatory stimuli. This occurs by binding to several receptor subtypes, defined P2X/P2Y, which are widespread in different tissues and simultaneously localized on multiple cells. For instance, the metabotropic P2Y12 subtype is found in the CNS on microglia, affecting activation and chemotaxis, on oligodendrocytes, possessing a hypothesized role in myelination, and on astrocytes. By comparative analysis, we have established here that P2Y12 receptor immunolabelled by antibodies against C-terminus or second intracellular loop, is, respectively, distributed and modulated under neuroinflammatory conditions on ramified microglia or myelinated fibers, in primary organotypic cerebellar cultures, tissue slices from rat striatum and cerebellum, spinal cord sections from symptomatic/end stage SOD1-G93A ALS mice, and finally autoptic cortical tissue from progressive MS donors. We suggest that modulation of P2Y12 expression might play a dual role as analytic marker of branched/surveillant microglia and demyelinating lesions, thus potentially acquiring a predictive value under neuroinflammatory conditions as those found in ALS and MS.

  10. Communities on the Verge of Extinction Meglenoromanians -Between Acculturation and Ethnic Dissolution

    Directory of Open Access Journals (Sweden)

    EMIL ŢÎRCOMNICU

    2009-04-01

    Full Text Available Among Romanian historical communities, two are currently close to ethnic and linguistic assimilation, due to their small number of members, the impossibility of claiming their cultural and linguistic rights, as well as the refusal of Balkan states to protect them. These groups are the Meglenoromanians and Istroromanians. In this study, we make a historical and ethnographic analysis of the small Meglenoromanian community, which was united until the Balkan wars, was split in two through the division of the Meglen land between Greece and the Serbian-Croatian-Slovenian Kingdom (1913, and then split again into two groups through the expulsion of Muslim Meglenoromanians to Turkey (1921 and the colonization of over 2 000 persons from Romania (in the Quadrilater, beginning in 1925, and afterwards in Cerna village, Tulcea county, in 1940.

  11. The Evolution of Criminality in Someş County on the Verge of World War II

    Directory of Open Access Journals (Sweden)

    GEORGE CRISTIAN SPÎNU

    2010-06-01

    Full Text Available This article refers to the characteristics and the evolution of criminality in Someş County, Romania, in 1938. The document supporting the analyses in this article is "Activitatea organelor poliţiei judiciare de sub Autoritatea Inspectoratului de Poliţie al Ţinutului Someş pe anul 1938" (The activity of judicial police bodies subordinated to the Someş County Police Inspectorate Authority in 1938". It contains the crimes recorded by the police authorities that year, along with their attempts at classifying them. With respect to the cases presented, they represent "snapshots" of the criminal events recorded by the police.

  12. High attack rate for malaria through irregular migration routes to a country on verge of elimination

    National Research Council Canada - National Science Library

    Wickramage, Kolitha; Premaratne, Risintha G; Peiris, Sharika L; Mosca, Davide

    2013-01-01

    ... of imported cases in Sri Lanka as it entered elimination phase. Beyond the criminality and human rights abuse, irregular migration plays an important, but often forgotten, pathway for malaria re-introduction...

  13. Readers of Caras y Caretas on the verge of the radical republic

    OpenAIRE

    Di Mare, María Fabiola

    2016-01-01

    Se propone un análisis de la lectura y los lectores de la revista Caras y Caretas durante el año 1916, momento de cambios en el sistema electoral y político de Argentina, en tanto que en ese año se celebra la primera elección presidencial bajo la Ley Sáenz Peña. Se intenta establecer una interpretación de las representaciones que ofrece la revista sobre sus lectores, a objeto de indagar en sus ámbitos de recepción y prácticas de lectura. Roger Chartier (1995, 2005), Néstor García Canclini (19...

  14. The sequels of the Fortunati ambo (Verg., Aen. IX 446-449: Epic and Empire.

    Directory of Open Access Journals (Sweden)

    Antonio Río Torres-Murciano

    2009-12-01

    Full Text Available In the well known apostrophe fortunati ambo (Aen. IX 446-449, Virgil ties literary durableness, which is a traditional aim of epic poetry, to the permanence of Roman empire. Nevertheless, this Virgilian analogy is put into question not only by Lucan, who overtly refutes it, but also by the epigones who, like Valerius Flaccus, Silius Italicus and Statius, look for their own way following in the great predecessor’s footsteps.

  15. Compassion Fatigue der Medien? Warum der deutsche „Flüchtlingssommer“ so rasch wieder verging

    Directory of Open Access Journals (Sweden)

    Kai Hafez

    2016-07-01

    Full Text Available Große deutsche Massenmedien haben im Frühjahr 2015 einen hilfsbereiteren Umgang der deutschen Regierung mit Flüchtlingen begünstigt, sie waren und sind aber auch mitverantwortlich für die negative Wende im öffentlichen Diskurs seit dem Herbst desselben Jahres. Die parallel verlaufenden Umbrüche des öffentlichen Meinungsklimas legen die Annahme einer starken aktiven Rolle und Wirkung von Medien nahe. Umso bedeutsamer erscheint die Suche nach Ursachen nicht nur für die advokative Rolle der Medien, sondern auch für deren plötzliche „Mitleidsmüdigkeit“. Populistische Neigungen, unklare Blattlinien und ein fehlender Konsens eines „Humanitätsjournalismus“ gehören zu den treibenden Kräften einer oft unrealistischen Krisenwahrnehmung, die nicht zuletzt den Rechtspopulismus begünstigt. Deutlich wird allerdings auch das Zerfallen eines Konsenses im politischen Machtzentrum des deutschen Regierungslagers, vor dessen Hintergrund sich die starke Medienwirkung erst entfalten konnte. Ein humanitärer Grundkonsens fehlt also auch hier.

  16. A country on the verge of malaria elimination--the Kingdom of Saudi Arabia.

    Directory of Open Access Journals (Sweden)

    Michael Coleman

    Full Text Available Significant headway has been made in the global fight against malaria in the past decade and as more countries enter the elimination phase, attention is now focused on identifying effective strategies to shrink the malaria map. Saudi Arabia experienced an outbreak of malaria in 1998, but is now on the brink of malaria elimination, with just 82 autochthonous cases reported in 2012. A review of published and grey literature was performed to identify the control strategies that have contributed to this achievement. The number of autochthonous malaria cases in Saudi Arabia decreased by 99.8% between 1998 and 2012. The initial steep decline in malaria cases coincided with a rapid scaling up of vector control measures. Incidence continued to be reported at low levels (between 0.01 and 0.1 per 1,000 of the population until the adoption of artesunate plus sulfadoxine-pyrimethamine as first line treatment and the establishment of a regional partnership for a malaria-free Arabian Peninsula, both of which occurred in 2007. Since 2007, incidence has decreased by nearly an order of magnitude. Malaria incidence is now very low, but a high proportion of imported cases, continued potential for autochthonous transmission, and an increased proportion of cases attributable to Plasmodium vivax all present challenges to Saudi Arabia as they work toward elimination by 2015.

  17. Diabetes insipidus and breast cancer - planning radiotherapy by the use of MRT. Diabetes insipidus und Mammakarzinom - Bedeutung der Kernspintomographie (MRT) zur Therapieplanung

    Energy Technology Data Exchange (ETDEWEB)

    Maeurer, J.; Busch, M.; Matthaei, D.; Duehmke, E. (Goettingen Univ. (Germany). Klinik und Poliklinik fuer Strahlentherapie); Helwig, A. (Goettingen Univ. (Germany). Abt. fuer Neuroradiologie)

    1993-02-01

    In patients with advanced breast cancer the incidence of diabetes insipidus is between 0,1% and 0,9%. Satisfactory symptomatic relief can be obtained with Desmorpressin-acetat. In the presence of this symptom complex magnetic resonance imaging (MRI) can aid in the detection of metastases to the posterior pituitary. By the use of magnetic resonance imaging, the incidence for and implementation of local radiotherapy can be firmly grounded. (orig.).

  18. Detection and characterization of left Ventricular Thrombi by MRT compared to Transthoracic Echocardiography; Detektion und Charakterisierung linksventrikulaerer Thromben mittels MRT im Vergleich zur transthorakalen Echokardiographie

    Energy Technology Data Exchange (ETDEWEB)

    Bruder, O.; Jochims, M.; Sabin, G.V. [Klinik fuer Kardiologie und Angiologie, Elisabeth - Krankenhaus Essen (Germany); Waltering, K.U.; Hunhold, P.; Narin, B.; Barkhausen, J. [Institut fuer Diagnostische und Interventionelle Radiologie, Universitaetsklinikum Essen (Germany)

    2005-03-01

    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.)

  19. On the Verge of History : Rupture and Continuity in Women’s Life Narratives from Hungary, Romania and Serbia

    NARCIS (Netherlands)

    Agardi, I.

    2013-01-01

    After 1989, with the end of communist rule in Central and Eastern Europe, narratives about rupture and change during a turbulent twentieth century have been told in many different forms, genres, and media alongside narratives of basic social and political continuities. Rupture and continuity emerged

  20. Iran’s Islamic Revolutionary Guard Corps in 2011: Is the IRGC on the Verge of Strategic Overreach?

    Science.gov (United States)

    2011-05-01

    approaching 30%.71 Layoffs are becoming a more regular occurrence, and it is becoming increasingly difficult for Iranians to obtain goods and materials...corruption stemming from the rapid acquisition of power and money coupled with the post-election crisis "and the ethical and ideological dilemmas that it

  1. Rapa Nui on the Verge: Easter Island’s Struggles with Integration and Globalization in the Information Age

    OpenAIRE

    Delaune, Gregory

    2012-01-01

    Rapa Nui (Easter Island, Chile), though previously cast in mystery and misunderstanding, has emerged as a global focus for indigenous land rights, thanks largely to increased global awareness made possible via  internet-enabled social media platforms. Beginning with the arrival of the first human settlers on the shores of this island paradise, the adverse consequences of human ingenuity, overpopulation, and globalization have pushed the island’s ecosystem beyond its carrying capacity, leading...

  2. A las puertas del cambio en la Formación Universitaria On the verge of change in University Education

    Directory of Open Access Journals (Sweden)

    Ana María Escayola Maranges

    2005-06-01

    Full Text Available Los cambios sociales conducen a un nuevo planteamiento en la docencia universitaria. Es necesario un modelo educativo abierto para formar nuevos profesionales competentes, basado en la capacidad de aprender del alumno, de obtener información y de adaptarse a las situaciones de cambio que presenta la profesión. La planificación de programas educativos plantea nuevos roles en la función del docente y del alumno, exige cambios metodológicos en el proceso de aprendizaje, conllevando cambios en las estrategias educativas. La nuevas tecnologías de la información y comunicación son un elemento indispensable para promover el cambio, aunque no suficientes. El aprendizaje basado en problemas (ABP ha resultado un elemento innovador en el ámbito universitario, demostrando un aumento de la motivación para aprender, potenciando el trabajo grupal, incentivando la búsqueda de información, aumentado la comprensión y la memorización del conocimiento. A su vez, el ABP pone énfasis en la interdisciplinariedad, aumenta el espíritu de colaboración del estudiante y su nivel de responsabilidad en el aprendizaje. En el ámbito de las Ciencias de la Salud, los métodos de aprendizaje son claves en el proceso formativo de profesionales competentes, dada la estrecha vinculación entre el ámbito laboral y formativo.Changes in society as a whole oblige University education to introduce changes as well. In order to train well-equipped professionals, an open educational model is necessary, based on the ability of the student to learn, to obtain information, and to adapt to the changes inside the profession. The planning of learning programs involves new roles for the teacher and new functions for the student. It requires changes in methodology and in educational strategies. The new information and communication technologies are indispensable instruments for promoting these changes, but they are not enough in isolation. Problem-based learning (PBL is an innovative instrument in the University setting, increasing students’ motivation, empowering group work, stimulating the search for information and increasing the comprensión and memorizing of knowledge. PBL also emphasizes interdisciplinary work, stressing the need to cooperate and to increase students’ responsibility for their learning. In the field of health sciences, effective learning methods are vital for the training of competent professionals due to the close connection between the educational and work environments.

  3. One medicine--one health--one biology and many proteins: proteomics on the verge of the One Health approach.

    Science.gov (United States)

    Roncada, Paola; Modesti, Alessandra; Timperio, Anna Maria; Bini, Luca; Castagnola, Massimo; Fasano, Mauro; Urbani, Andrea

    2014-06-01

    Starting from Hippocrates, at the Age of Pericles, the One Health initiative takes inspiration from the Greek father of medicine and is based on his approach which recognizes that human health, animal health and environmental health are part of a whole body. Chiron, the wisest of all centaurs, is the classical mythological representation of an integrated view between man and the environment. Thus, he is the tangible example of the Hippocratic dyad where healthcare is achieved by the integration of man with nature. As a mythological Chiron in modern systems medicine, the integrated body of evidence in proteomics investigations is providing key molecular and analytical knowledge to achieve an evidence based approach. Hereafter we introduce some examples published in this themed proteomics issue.

  4. 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.)

  5. Measurement of MRI scanner noise; Schalldruckpegelmessungen an einer MRT-Anlage

    Energy Technology Data Exchange (ETDEWEB)

    Knoergen, M.; Spielmann, R.P.; Melkus, G. [Klinik fuer Diagnostische Radiologie, Klinikum der Martin-Luther-Univ. Halle-Wittenberg (Germany); Haberland, E.J. [Klinik fuer Hals-, Nasen-, Ohrenheilkunde, Kopf- und Halschirurgie, Klinikum der Martin-Luther-Univ. Halle-Wittenberg (Germany)

    2004-07-01

    The present paper describes a simple method for the analysis of MRI scanner noise. Besides the heating of body tissue by strong RF radiation and the formation of circular currents in the body induced bey switching field gradients, a noise level of more than 100 dB(A) during the measurement belongs to the potential risks of MRI [1,2]. This risk is of particular concern for staff and accompanying persons who remain close to the scanner for different reasons (e.g., monitoring of anesthetized patients, reassuring of children). For this reason, and given the scanty information on noise provided in the manuals of the scanners, it is useful to quantify the noise level more exactly. This applies also to the evaluation of different sound-reducing methods for the patient. This presents the results of noise level measurements in the tomograph and in its surrounding, with and without noise reduction by headphones. (orig.)

  6. Morphology and classification of cerebral cavernomas on MRI. MRT-Morphologie und Klassifikation der zerebralen Kavernome

    Energy Technology Data Exchange (ETDEWEB)

    Schefer, S.; Valavanis, A.; Wichmann, W. (Zurich Univ. (Switzerland). Abt. fuer Neuroradiologie)

    1991-06-01

    An MRI review of 54 histologically verified cavernomas allowed the introduction of a system classifying this cavernous venous malformation into four types: Type I (20%) corresponds to the classic morphology of a cavernoma without hemorrhage; type II (67%) is characterized by intralesional hemorrhage; type III (11%) is associated with an extralesional hemorrhage that compresses or displaces the cavernoma itself; and type IV (2%) corresponds to a totally calcified cavernoma. These variable cavernoma types represent different possible stages of the natural evolution of a cavernoma and limit the differential diagnosis, especially in the group of occult or cryptic cerebral vascular malformations. (orig.).

  7. MRI in degenerative diseases of the cervical spine. MRT bei degenerativen Halswirbelsaeulenerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Schubeus, P. (Strahlenklinik mit Poliklinik, Universitaetsklinikum Rudolf Virchow, Berlin (Germany)); Sander, B. (Strahlenklinik mit Poliklinik, Universitaetsklinikum Rudolf Virchow, Berlin (Germany)); Hosten, N. (Strahlenklinik mit Poliklinik, Universitaetsklinikum Rudolf Virchow, Berlin (Germany)); Mayer, H.M. (Strahlenklinik mit Poliklinik, Universitaetsklinikum Rudolf Virchow, Berlin (Germany)); Weber, U. (Strahlenklinik mit Poliklinik, Universitaetsklinikum Rudolf Virchow, Berlin (Germany)); Felix, R. (Strahlenklinik mit Poliklinik, Universitaetsklinikum Rudolf Virchow, Berlin (Germany))

    1994-01-01

    MRI has grown increasingly important in recent years in diagnosis of degenerative diseases of the cervical spine, due to improvements of method that have made it a valuable diagnostic tool. The following contribution gives a brief introduction to the pathophysiology of degenerative changes in the cervical vertebral column and to the indications for MRI, describing within the framework of imaging the present state of MR examination technique. The ranking of the various gradient echo sequences, of the 3D methods and of the administration of contrast media in cervical myelopathy and radiaculopathy is discussed. (orig.)

  8. Gliomatosis cerebri: The diagnostic potential of MRI. Gliomatosis cerebri: Diagnostisches Potential der MRT

    Energy Technology Data Exchange (ETDEWEB)

    Rodiek, S.O.; Hufnagl, J.M. (Staedtisches Krankenhaus Muenchen-Bogenhausen (Germany). Abt. fuer Roentgendiagnostik und Nuklearmedizin Staedtisches Krankenhaus Muenchen-Bogenhausen (Germany). Abt. fuer Neuropsychologie)

    1991-07-01

    Gliomatosis cerebri is a rare tumor of neuroepithelial origin in middle aged persons. MRI predominantly shows a bilateral and diffuse infiltration of midline adjacent brain structures including medulla. Areas with focal anaplasia occasionally reveal an accumulation of contrast media. The diffuse tumor manifestation requires a differentiation from encephalitis and demyelinating diseases with a similar distribution pattern of lesions. Three cases have been examined. In conclusion the performance of MRI including control and brain biopsy are indicated to establish an in vivo diagnosis. (orig./GDG).

  9. 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.

  10. 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.

  11. 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 beforeand 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 concentrationswere 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. PMID:22038692

  12. Prostate treatments, 1MRT o RapidArc; Tratamiento de prostata, IMART o RapidArc?

    Energy Technology Data Exchange (ETDEWEB)

    Castro novais, J.; Ruiz Maqueda, S.; Pardo Perez, E.; Molina Lopez, M. Y.; Cerro Penalver, E.

    2015-07-01

    Techniques that modulate the dose (as IMRT or RapidArcTM) improve dose homogeneity within the target volume decreasing the dose in healthy organs. The aim of this work is to study the dosimetric differences in prostate radiotherapy treatments with IMRT and RapidArcTM. The results of the 109 patients studied show that plans to RapidArcTM have better coverage, compliance and dose gradient outside the target volume. (Author)

  13. Räumliche Orientierung auf dem mentalen Zahlenstrahl : eine kombinierte Reaktionszeit- und fMRT-Studie

    OpenAIRE

    Mahr, Martin Moritz

    2010-01-01

    Semantic number magnitude is represented in an analogue visual-spacial system in the shape of a left-to-right oriented, logarithmically compressed mental number line; the most important evidence is the SNARC (Spatial Numerical Association of Response Codes)-effect (Dehaene, Bossini & Giraux, 1993). In the actual study the spacial characteristics of number processing and of the mental number line were examined by use of behavioral data and functional imaging. It was of special interest, if the...

  14. Dynamic function MR of the cervical vertebral column. Dynamische Funktions-MRT der Halswirbelsaeule

    Energy Technology Data Exchange (ETDEWEB)

    Naegele, M.; Woell, B.; Reiser, M. (Radiologische Universitaetsklinik, Bonn (Germany)); Koch, W. (Orthopaedische Universitaetsklinik, Bonn (Germany)); Kaden, B. (Neurochirurgische Universitaetsklinik, Bonn (Germany))

    1992-09-01

    To obtain functional studies of the cervical spine, a device has been developed which allows MRI examinations to be carried out in five different degrees of flexion. T[sub 1] and T[sub 2][sup *] weighted FFE sequences were used. Dynamic functional MRI was performed on 5 normals and 31 patients (5 disc herniation, 4 whiplash injuries, 6 spinal canal stenoses, 14 laminectomies and spinal fusions, 2 rheumatoid arthritis). The relationship of the spinal cord to the bony and ligamentous components in different degrees of flexion was particularly well shown in whiplash injury, spinal stenosis and postoperative situations. (orig.).

  15. 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.)

  16. 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.

  17. MRI for the detection of anorectal fistulas; MRT in der Diagnostik anorektaler Fisteln

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, A.O.; Baumann, T.; Langer, M. [Abt. Roentgendiagnostik, Universitaetsklinikum Freiburg (Germany)

    2006-11-15

    MRI is accepted as one of the major diagnostic tools for the detection of anorectal fistulas and abscesses. Noninvasiveness and high accuracy are advantageous hallmarks of this technique. In general, the purpose of imaging anal fistulas is to reduce the risk of recurrence, incontinence and non-healing. To achieve these goals, the applied method must provide the proctologist with detailed information. In this context, MRI acts as a guide for surgeons to accurately plan fistula operations. Another aspect is the follow-up of conservatively treated patients with fistulizing Crohn's disease. In 2000, subtraction MR fistulography was introduced as new imaging technique. This review provides an overview of the entire spectrum of diagnostic modalities for anorectal fistulas with emphasis on subtraction MR fistulography. (orig.)

  18. 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.

  19. [The MRT of scaphoid pseudarthrosis with Gd-DTPA. Its staging and clinical correlation].

    Science.gov (United States)

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

    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 T1 weighted spin echo sequences in sagittal and frontal projection and frontal FLASH T2 sequences and axial spin echo T2 sequences. The T1 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 T1 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.

  20. 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...

  1. MRT letter: full-tilt electron tomography with a piezo-actuated rotary drive.

    Science.gov (United States)

    Xu, X J; Lockwood, A; Guan, W; Gay, R; Saghi, Z; Wang, J J; Peng, Y; Inkson, B J; Möbus, G

    2008-11-01

    Piezoelectric nanoactuation, which is rapidly becoming established as state-of-the-art positioning control in transmission electron microscopy (TEM), is extended here to include a rotational degree of freedom. A piezoelectric goniometer with both translational and rotary drive action has been designed with high level of miniaturization to fit into a standard TEM specimen holder shaft without compromising any of the performance of the default TEM goniometer and without any modifications to the TEM. Enhanced functionality of such a goniometer-in-goniometer is outlined and experimental results for electron tomography of nanostructures over a full tilt range of views, without any missing angles, are demonstrated.

  2. MRT letter: An extended scanning probe microscopy system for macroscopic topography imaging.

    Science.gov (United States)

    Fu, Ji; Li, Faxin

    2014-10-01

    Enlightened by the principle of scanning probe microscopy or atomic force microscope (AFM), we proposed a novel surface topography imaging system based on the scanning of a piezoelectric unimorph cantilever. The height of sample surface can be obtained by recording the cantilever's strain using an ultra-sensitive strain gauge and the Z-axis movement is realized by electric bending of the cantilever. This system can be operated in the way similar to the contact mode in AFM, with the practical height detection resolution better than 100 nm. Imaging of the inner surface of a steel tube and on a transparent wing of a honey bee were conducted and the obtained results showed that this proposed system is a very promising solution for in situ topography mapping. © 2014 Wiley Periodicals, Inc.

  3. MRT 5711 - Scope Radiochemical Analysis Comparison: Joint LANL-LLNL FY17 L-2 Milestone

    Energy Technology Data Exchange (ETDEWEB)

    Murray, S. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Lee, A. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-14

    A 2016 Level-1 milestone highlighted surprising differences in fundamental data used by the two US design laboratories. To better understand and ultimately resolve those differences, two Level-2 milestones were developed for execution in FY-17 and FY-18.

  4. MRT letter: Guided filtering of image focus volume for 3D shape recovery of microscopic objects.

    Science.gov (United States)

    Mahmood, Muhammad Tariq

    2014-12-01

    In this letter, a shape from focus (SFF) method is proposed that utilizes the guided image filtering to enhance the image focus volume efficiently. First, image focus volume is computed using a conventional focus measure. Then each layer of image focus volume is filtered using guided filtering. In this work, the all-in-focus image, which can be obtained from the initial focus volume, is used as guidance image. Finally, improved depth map is obtained from the filtered image focus volume by maximizing the focus measure along the optical axis. The proposed SFF method is efficient and provides better depth maps. The improved performance is highlighted by conducting several experiments using image sequences of simulated and real microscopic objects. The comparative analysis demonstrates the effectiveness of the proposed SFF method. © 2014 Wiley Periodicals, Inc.

  5. MRT letter: application of novel "in vivo cryotechnique" in living animal kidneys.

    Science.gov (United States)

    Li, Zilong; Li, Kai; Wang, Juan; Zhai, Xiaoyue; Wang, Lining; Ohno, Nobuhiko; Ohno, Shinichi

    2013-02-01

    To compare the influence of different fixation procedures on morphologic studies in living mice, and to identify the advantages of the "in vivo cryotechnique" (IVCT). We prepared mouse kidneys using four different fixation methods: conventional immersion-fixation, quick-freezing following resection of the kidney, quick-freezing following perfusion-fixation, and IVCT. Kidney glomeruli were noticeably contracted after conventional immersion-fixation or quick-freezing following resection compared to glomeruli from tissues preserved by the IVCT. With the IVCT, both albumin and IgG were colocalized exclusively along or within the glomerular capillary loops; however, immunoreactivity of these proteins in the other three methods was clearly detected in the Bowman's space and apical cytoplasm of the proximal tubules. With the IVCT, immunoreactivity of collagen type IV was very weak at the glomerular basement membrane (GBM) until microwave treatment, which increased its immunoreactivity. In contrast, the immunoreactivity was clearly detected at the GBM with or without microwave treatment with quick-freezing following perfusion-fixation. With quick-freezing following perfusion-fixation, aquaporin-1 (AQP-1) was irregularly distributed in a disorganized manner on the brush border and apical cell membrane along the proximal tubules. But AQP-1 was labeled intensely and regularly along the brush border and apical cell membrane andonly weakly along the basolateral membrane of the proximal tubules with the IVCT. The IVCT may reliably maintain soluble serum proteins and renal intrinsic proteins such as AQP-1 in situ and capture transient structures and functional changes in vivo. Copyright © 2012 Wiley Periodicals, Inc.

  6. MRT letter: Micro- to nanoscale sample collection for high throughput microscopy.

    Science.gov (United States)

    Cheong, Brandon Huey-Ping; Liew, Oi Wah; Ng, Tuck Wah

    2013-08-01

    In high throughput microscopy, it is often assumed that the objects under investigation are fixed spatially. In addition, it is also presumed that the objects are sufficiently populated, otherwise there will be need to search through vast tracks of field of views before any recording can be done. The ability to collect objects at one location in the hydrated state is thus desirable and this is a challenge when the density of target objects in a sample is very low. In this work, we report that the generation of a squeezing flow from a circular coverslip compressing on suspensions is able to collect particulate (microbeads, fluorescent nanobeads and live algal cells) and non-particulate (EGFP) objects at the rim region of the coverslip. With a coverslip of 13 mm diameter, volumes between 2 µL and 4 µL were found to completely fill the coverslip without breaching the rims. Sample compression speeds between 100 µm/s and 1000 µm/s did not have any effect on object collection outcomes. In effect, the simple placement of coverslips on top the drop of sample by hand without a motorized translator was found to produce similar collection outcomes. Quantitative measurements confirmed that all the objects investigated were displaced and relocated at the rim regions to a very high degree. Copyright © 2013 Wiley Periodicals, Inc.

  7. MRT letter: Nanoscopy of protein colocalization in living cells by STED and GSDIM.

    Science.gov (United States)

    Lalkens, Birka; Testa, Ilaria; Willig, Katrin I; Hell, Stefan W

    2012-01-01

    We report the use of superresolution fluorescence microscopy for studying the nanoscale distribution of protein colocalization in living mammalian cells. Nanoscale imaging is attained both by a targeted and a stochastic fluorescence on-off switching superresolution method, namely by stimulated emission depletion (STED) and ground state depletion microscopy followed by individual molecular return (GSDIM), respectively. Analysis of protein colocalization is performed by bimolecular fluorescence complementation (BiFC). Specifically, a nonfluorescent fragment of the yellow fluorescent protein Citrine is fused to tubulin while a counterpart nonfluorescent fragment is fused to the microtubulin-associated protein MAP2 such that fluorescence is reconstituted on contact of the fragment-carrying proteins. Images with resolution down to 65 nm prove a powerful new way for studying protein colocalization in living cells at the nanoscale. Copyright © 2011 Wiley Periodicals, Inc.

  8. MRT letter: Quantum noise removal and classification of breast mammogram images.

    Science.gov (United States)

    Naseem, M Talha; Sulong, Ghazali Bin; Jaffar, M Arfan

    2012-12-01

    Because of the limitations of the X-ray hardware systems in mammogram machines, the quality of the breast mammogram images may undergo from poor resolution or low contrast. Quantum noise occurs in the mammogram images during acquisition due to low-count X-ray photons. In this work, an adaptive frost filter has been used to remove quantum noise. Local binary patterns have been extracted to classify breast mammograms into benign and malignant using different classifiers. Results show the superiority of the proposed algorithm in terms of sensitivity, specificity, and accuracy. Mammographic Institute Society Analysis database of mammography has been used for experimentation. Peak signal-to-noise ratio and structural similarity index measure are used to test the validity of adaptive frost filter. Experiment results show that proposed technique produces better results. Copyright © 2012 Wiley Periodicals, Inc.

  9. Cinematographic techniques in the diagnostics of intestinal diseases using MRT enteroclysma.

    Science.gov (United States)

    Röttgen, Rainer; Ocran, Kenneth; Lochs, Herbert; Hamm, Bernd

    2009-01-01

    We investigated whether an additional cine sequence in MR enteroclysis examination is practicable and would provide additional findings in the diagnostics of patients with abdominal diseases. Seventeen consecutively presenting patients with known or presumed abdominal disease (known or presumed intestinal illness; age range, 21-57 years; mean age, 34.1 years; male:female ratio, 4:13) were retrospectively studied. All patients underwent MRI enteroclysis at 1.5 T subsequent to conventional ileocolonoscopy, which was used as reference standard. A gastroenterologist and a radiologist evaluated the MRI examinations together to see whether the additional cine sequences would provide any additional findings. The cine sequences provided relevant diagnostic information in at least 11 of 17 patients (60.6%). In five patients, we were able to determine a stenosis as scarred; in two patients, normal peristalsis of the bowel was demonstrated, showing that the stenosis had not been scarred. This study provides strong evidence that the implementation of cine sequences in MRI enteroclysis examination provides additional findings with clinical relevance, especially for distinguishing scarred and functional stenoses.

  10. 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.

  11. 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.

  12. MRT letter: segmentation and texture-based classification of breast mammogram images.

    Science.gov (United States)

    Naveed, Nawazish; Jaffar, M Arfan; Choi, Tae-Sun

    2011-11-01

    Breast cancer is the most common cancer diagnosed among women. In this article, support vector machine is used to classify digital mammogram images into malignant and benign. Wiener filter is used to handle the possible quantum noise, which is more likely to occur in mammograms. Stack-based connected component method is proposed for background removal, and the image is enhanced using retinax method. Seeded region growing algorithm is used to remove the pectoral muscle part of the mammogram. We have extracted 13 different multidomains' features for classification. Results show the superiority of the proposed algorithm in terms of sensitivity, specificity, and accuracy. We have used MIAS database of mammography for experimentation. Copyright © 2011 Wiley Periodicals, Inc.

  13. MRT letter: In situ observation method for microstructural changes of steel during hot deformation.

    Science.gov (United States)

    Yogo, Yasuhiro; Takeuchi, Hirohisa; Tanaka, Kouji; Iwata, Noritoshi; Nakanishi, Koukichi; Ishikawa, Takashi

    2009-12-01

    We report on the result of an in situ method for observing microstructural changes during hot deformation. The observation of microstructural changes of steel at 1,473 K under tensile strain is demonstrated using the reported method. The development of deformed structures and the formation of a new grain boundary, which subsequently moved with increased strain, were clearly observed. The effectiveness of this method was confirmed by the results of several examples.

  14. MRT letter: Optimal composite depth function for 3D shape recovery of microscopic objects.

    Science.gov (United States)

    Majid, Abdul; Mahmood, Muhammad Tariq; Choi, Tae-Sun

    2010-07-01

    Generally, in shape from focus techniques, a single focus measure is used in estimating the three-dimensional structure of microscopic objects. However, the performance of a single focus measure is limited to estimate accurately the depth map of diverse type of objects. To cope with this problem, we propose genetic programming based novel approach by developing an optimal composite depth (OCD) function for accurate depth estimation. This OCD function optimally combines the initial depth and focus information extracted from individual focus measures. An improved performance of this function is reported for synthetic and real world microscopic objects. (c) 2010 Wiley-Liss, Inc.

  15. 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.)

  16. Vergüenza de vivir donde vivo”: ideas para una re-conceptualización de la segregación residencial socioeconómica

    Directory of Open Access Journals (Sweden)

    Susana Cortés

    2008-09-01

    Full Text Available Santiago, capital de Chile, se caracteriza por un patrón distributivo de segregación residencial socioeconómica en gran escala, sin espacios urbanos de contacto entre los habitantes de diferentes estratos sociales. Sin embargo, en las últimas dos décadas se ha observado casos en que la escala geográfica de segregación residencial se ha reducido, acortándose la distancia entre familias de muy bajos y altos ingresos en comunas periféricas, originalmente ocupadas por campamentos y habitantes de escasos recursos, hoy vecinos de condominios cerrados. ¿Constituye este fenómeno una nueva tendencia distributiva o son sólo casos aislados?; ¿qué efectos socioespaciales tiene para estas comunas, sus habitantes y la ciudad, a corto y largo plazo?; ¿puede la reducción de escala de segregación residencial generar instancias de interacción e integración social? Este artículo reflexiona en torno a estas preguntas sobre el caso particular de la comuna de Peñalolén. Analiza los efectos negativos del fenómeno así como ideas sobre por qué la interacción e integración social no son consecuencias naturales de la cercanía física en el actual contexto social y económico de Chile y del mundo globalizado. Finalmente, en base a la teoría de la lógica del espacio de los flujos de Manuel Castells, y su aplicación al caso estudiado, se reflexiona sobre las definiciones de segregación residencial y las metodologías para su estudio, proponiendo la necesidad de una re-conceptualización que incluya nuevas técnicas, enfatizando la metodología cualitativa que la Antropología puede aportar.

  17. Circumplanetary Debris Disks in the Solar System and Beyond: Is the Fomalhaut System on the Verge of a Late Heavy Bombardment?

    Science.gov (United States)

    Tamayo, Daniel; Burns, J. A.

    2014-01-01

    Each of the Solar System’s giant planets hosts many small and distant irregular satellites. These moons’ radially overlapping orbits and their unusually shallow size distributions imply a violent collisional history (Bottke et al. 2010). Thus, at early epochs, the giant planets likely displayed prominent circumplanetary debris clouds. For my PhD I numerically studied how such debris in the Saturnian system would evolve inward through radiation forces to coat the striking two-faced moon Iapetus (Tamayo et al. 2011). I also investigated the analogous process at Uranus, where the planet’s extreme obliquity renders infalling dust orbits chaotic. We find that this could explain the color dichotomies observed on the largest four Uranian satellites (Tamayo et al. 2013a, 2013b). Even today, Saturn has such a vast dust disk, sourced by the irregular satellite Phoebe (Verbiscer et al. 2009). This ‘Phoebe Ring’, can be used to observationally study the gravitational effects of moons on the dust; I have successfully probed this ring with Cassini, but was unsuccessful with Herschel observations. By these combined observational and dynamical studies, I hope to inform the field of extrasolar debris disks, where one tries to use dust signatures to infer the existence of planets that are too faint to see. I am now focusing on a related problem involving the exoplanet candidate Fomalhaut b (Kalas et al. 2008). While its optical flux is too large to come directly from a planet, perhaps we are observing a disk supplied by irregular moons like the Phoebe Ring(Kennedy & Wyatt 2011). Additional observation epochs imply that Fomalhaut-b’s orbit is very eccentric (Kalas et al. 2013). Yet despite crossing the system’s observed circumstellar debris disk in projection, Fomalhaut b does not appear to have significantly disturbed it. We argue from simulations that if Fomalhaut b is a giant planet, it must have scattered into its present orbit in the past ~10 Myr. Furthermore, if it is the only object dynamically interacting with the belt, the debris disk’s eccentricity will continue rising to values near unity, perhaps causing an event analogous to the Late Heavy Bombardment hypothesized to have occurred in the early Solar System.

  18. Brachytherapy of penis cancer: experience of the Gustave-Roussy Institute; Curietherapie des cancers de verge: experience de l'Institut Gustave-Roussy

    Energy Technology Data Exchange (ETDEWEB)

    Crevoisier, R. de; Wibault, P.; M' barek, B.; Gerbaulet, A.; Haie-Meder, C. [Institut Gustave-Roussy, 94 - Villejuif (France)

    2006-11-15

    The interstitial brachytherapy is a conservative treatment of epidermoid carcinomas of the penis under 4 centimeters and does not invade the erectile tissue. the great majority of recurrences is under control by a surgery treatment. (N.C.)

  19. Work practices and the provision of mental-health care on the verge of reform: a national survey of Israeli psychiatrists and psychologists.

    Science.gov (United States)

    Nirel, Nurit; Samuel, Hadar

    2014-01-01

    The State of Israel is preparing to transfer legal responsibility for mental- health care from the government to the country's four competing, nonprofit health-plans. A prominent feature of this reform is the introduction of managed care into the mental-health system. This change will likely affect the service delivery patterns and care practices of professional caregivers in mental-health services. The study examines psychiatrists' and psychologists' patterns of service delivery and practice, and their attitudes toward the reform's expected effects, focusing on the following questions: To what extent do today's patterns of service delivery suit a managed-care environment? To what extent do professionals expect the reform to change their work? And do psychiatrists and psychologists differ on these questions? A survey of 1,030 psychiatrists and psychologists using a closed mail questionnaire for self-completion was conducted from December 2011 to May 2012. Substantial differences were found between psychiatrists' and psychologists' personal and professional characteristics, work patterns, and treatment-provision characteristics. In addition, the study identified gaps between the treatment-provision characteristics of some of the professionals, mostly psychologists, and the demands of a managed-care environment. Moreover, a high percentage of the mental-health professionals (mostly psychologists) do not expect improvement in the quality of care or its accessibility and availability following the reform. However, those reporting practices associated with managed care (e.g. short-term treatment, compliance with monitoring procedures, and emphasis on evidence-based treatment) are less likely to expect negative changes in the provision and quality of care after the reform. Steps need to be taken to reduce the gaps between the treatment-provision characteristics of the professionals and the demands of a managed-care environment, and there are several possible ways to do so. In order to recruit experienced, skilled professionals, the health plans should consider enabling various work models and offering training focused on the demands of working in a managed-care environment. It is advisable to implement this kind of training also during the training and specialization process by including these topics in the professional curricula.

  20. Plant invasion: Another threat to the São Paulo Marsh Antwren (Formicivora paludicola, a species on the verge of extinction.

    Directory of Open Access Journals (Sweden)

    Glaucia Del-Rio

    Full Text Available During the past 100 years in densely populated south-eastern Brazil, wetlands have been severely transformed due to urbanization, agriculture and mining. The recently discovered São Paulo Marsh Antwren (Formicivora paludicola is endemic to these wetlands, and is listed as "Critically Endangered" by the IUCN. The species is only found in an area of 1.42 km2, it has a sparse and fragmented distribution, low dispersal capacity, and has probably lost around 300 km2 of habitat in the past 100 years. Furthermore, very little is known about F. paludicola natural history, and so it is difficult to construct a robust conservation plan. Using Kernel home range estimations and the Adjusted-SD/Torus Shift test (a novel tool for animal-habitat association studies, we showed that the species avoids patches of the alien invasive ginger lily (Hedychium coronarium. Given the high density of their population (3.6 mature individuals/ha, F. paludicola could thrive in relatively small areas of suitable wetlands protected from human occupation and water contamination, however special attention should be paid to biological invasions, which may represent a serious threat to the remaining populations. Protecting a few small wetlands used by F. paludicola would be an important step towards general conservation and restoration of Atlantic Forest wetlands and its endemic endangered species.

  1. Corporate Social Responsibility on the verge of becoming an institutionalized norm? Case study : The Varner-Group's CSR work in India

    OpenAIRE

    Kåsin, Karianne; Skogseth, Ingrid Kvinge

    2014-01-01

    The purpose of this thesis is to illuminate the importance of researching Corporate Social Responsibility (CSR) in International Relations (IR), through a social constructivist perspective. This is a two-folded study. The first part of the study sets out to investigate the development of CSR as an international norm, and seeks to identify the drivers of CSR as a norm in Norway and India. The second part of the thesis is a case study of the Norwegian textile company, the Varner-Group. ...

  2. Sin-vergüenza. Análisis goffmaniano de la capacitación en un programa de empleo

    Directory of Open Access Journals (Sweden)

    Diego Quattrini

    2016-01-01

    Full Text Available El objetivo del estudio es analizar la educación de la competencia “buena presencia”, que deben asumir los jóvenes de los sectores vulnerables para ingresar al mercado laboral en la provincia de Mendoza (Argentina. Para dicho fin, utilizo algunos aportes conceptuales de la teoría de Erving Goffman. Atendiendo al diseño metodológico, elaboré en el año 2013 entrevistas en profundidad a técnicos y jóvenes de un programa de empleo y capacitación laboral. Mediante esta técnica busco observar el manejo corporal-emocional que se produce en la presentación, en la búsqueda de empleo. Así, la pregunta es por la forma en que se construye la sensación de reconocimiento ante la regulación que se produce por la mirada de los otros. La inclusión está dada, entonces, por lograr una presentación estética y emocionalmente validada por el orden de la interacción.

  3. 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.)

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

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    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.)

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

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    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.

  6. 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.)

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

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    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. Clinical application of diffusion-weighted MRI of the brain; Der klinische Einsatz der diffusionsgewichteten MRT am Gehirn

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    Fiebach, J.B.; Harting, I. [Universitaetsklinikum Heidelberg (Germany). Abt. Neuroradiologie

    2004-09-01

    Diffusion-weighted MRI (DWI) has become a routine imaging procedure in many clinical situations. In contrast to conventional sequences that only show morphology, DWI gives an insight into physical phenomena. DWI has a major impact in acute stroke imaging. Relevant information can be retrieved from DWI in brain tumors, inflammatory and infectious CNS disease, brain abscess or venous thrombosis. In this article, basic principles of DWI and standard clinical applications will be illustrated. (orig.)

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

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    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.)

  10. Normal cardiac diameters in cine-MRI of the heart; Normalwerte der Herzdurchmesser in der Cine-MRT

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    Hergan, K.; Schuster, A.; Mair, M.; Burger, R.; Toepker, M. [Zentrales Inst. fuer Radiologie, Landeskrankenhaus Feldkirch (Austria)

    2004-11-01

    Purpose: To measure the normal diameters of cardiac cavities in standard cardiac views using cine MRI. Materials and Methods: Fifty-six volunteers were examined (27 male, 29 female) on a 1.5 T MR unit with ECG-triggered single shot free precision (SSFP) cine MR sequences and parallel image acquisition. Standardized echocardiographic planes were used to depict the heart of all volunteers (short axis, 4-chamber view, left and right 2-chamber views). The different diameters of the cardiac cavities were measured using a fixed protocol. Results: For the estimation of ventricular dilatation, the important female/male cross diameters of the left ventricle are 45.2{+-}3.4/51.6{+-}4.6 mm diastolic and 30.5{+-}3.5/33.8{+-}3.6 mm systolic, and of the right ventricle 30.7{+-}3.8/37.1{+-}5.9 mm diastolic and 22.3{+-}3.8/28.1{+-}4.4 mm systolic. For the determination of a left ventricular hypertrophy, relevant septal wall thickness measured in the short axis of the left ventricle of female/male volunteers are 8.0{+-}1.0/9.9{+-}1.2 mm diastolic and 10.9{+-}1.4/13.6{+-}1.9 mm systolic. The measured normal values of male volunteers were generally higher than those of female volunteers. The thickness of the ventricular septum correlated well when measured in the short axis and 4-chamber view. When measured in the 4-chamber view, the longitudinal diameter of the ventricles had a higher value in diastole and a lower value in systole, compared to the 2-chamber views of the right and left cardiac cavities. The atrial longitudinal diameters were higher in the 4-chamber view compared to the 2-chamber views, without any difference in systole or diastole. Conclusion: Diameters of cardiac cavities are easily and quickly measured. Using the tables with the normal values published here, it is simple to estimate an abnormal size of the heart. (orig.)

  11. Diagnosis of coronary artery disease. Current status of MRI; Diagnostik der koronaren Herzkrankheit. Aktueller Stand der MRT

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    Lotz, Joachim [Abt. Diagnostische Radiologie, Universitaetsmedizin Goettingen (Germany)

    2010-06-15

    MRI has become an imaging option in the workup of coronary artery disease. Usually three techniques are combined to address the question of myocardial ischemia and viability: Cine cardiac imaging for the assessment of wall motion and cardiac function; first pass perfusion imaging during maximal vasodilatation for the detection of myocardial ischemia and late enhancement imaging for visualization of myocardial scars. This approach allows the assessment of inducible subendocardial myocardial ischemia as well as of the extend of prior myocardial infarction. Non-ischemic causes of myocardial damage can be differentiated from coronary artery disease within the same examination. Results from cardiac MRI are relevant in the risk assessment for major cardiac events. Direct visualization of coronary arteries is inferior to cardiac CT. MR coronary angiography is not recommended as a routine diagnostic tool in the workup of coronary artery disease. MRI is superior in myocardial contrast resolution to CT. Additionally, it has a superior spatial resolution in comparison to the myocardial SPECT or PET. Cardiac MRI is technically demanding and thereby limited in its availability compared to myocardial SPECT or cardiac CT. (orig.)

  12. The Selective Separation of Anions and Cations in Nuclear Waste Using Commercially Available Molecular Recognition Technology (MRT) Products

    Energy Technology Data Exchange (ETDEWEB)

    Izatt, S. R.; Bruening, R. L.; Krakowiak, K. E.; Izatt, R. M.

    2003-02-25

    This paper describes the use of some of IBC's SuperLig{reg_sign}, MacroLig{reg_sign}, and AnaLig{reg_sign} molecular recognition technology products to effectively and selectively separate and recover cesium, technetium, strontium, and radium from radioactive waste solutions. Distinct advantages are given over conventional separation techniques. Separations are described and results given for the target ions over chemically similar ions often present at much higher concentrations. The separations are performed in solutions of either high or low pH and usually containing high concentrations of salts. Other separations involving components of radioactive and mixed waste are noted.

  13. Rapid total body fat measurement by magnetic resonance imaging: quantification and topography; Schnelle Ganzkoerperfettmessung mittels MRT: Quantifizierung und Topografie

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, F.M.; Hunold, P.; Greiff, A. de; Nuefer, M.; Barkhausen, J.; Ladd, S.C. [Uniklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie; Ruehm, S. [David Geffen School of Medicine at UCLA (United States). Dept. of Radiology

    2007-05-15

    Purpose: To evaluate a rapid and comprehensive MR protocol based on a T1-weighted sequence in conjunction with a rolling table platform for the quantification of total body fat. Materials and Methods: 11 healthy volunteers and 50 patients were included in the study. MR data was acquired on a 1.5-T system (Siemens Magnetom Sonata). An axial T1-weighted flash 2D sequence (TR 101, TE 4.7, FA 70, FOV 50 cm, 205 x 256 matrix, slice thickness: 10 mm, 10 mm interslice gap) was used for data acquisition. Patients were placed in a supine position on a rolling table platform capable of acquiring multiple consecutive data sets by pulling the patient through the isocenter of the magnet. Data sets extending from the upper to lower extremities were collected. The images were analyzed with respect to the amount of intraabdominal, subcutaneous and total abdominal fat by semi-automated image segmentation software that employs a contour-following algorithm. Results: The obtained MR images were able to be evaluated for all volunteers and patients. Excellent correlation was found between whole body MRI results in volunteers with DEXA (r{sup 2} = 0.95) and bioimpedance (r{sup 2} = 0.89) measurements, while the correlation coefficient was 0.66 between MRI and BMI, indicating only moderate reliability of the BMI method. Variations in patients with respect to the amount of total, subcutaneous, and intraabdominal adipose tissue was not related to standard anthropometric measurements and metabolic lipid profiles (r{sup 2} = 0,001 to 0.48). The results showed that there was a significant variation in intraabdominal adipose tissue which could not be predicted from the total body fat (r{sup 2} = 0.14) or subcutaneous adipose tissue (r{sup 2} = 0.04). Although no significant differences in BMI could be found between females and males (p = 0.26), females showed significantly higher total and subcutaneous abdominal adipose tissue (p < 0.05). Conclusion. (orig.)

  14. [Spiral CT and MRT of the operated Stanford-type-A aortic dissection: its course and complications].

    Science.gov (United States)

    Sommer, T; Abu-Ramadan, D; Pauleit, D; Hofer, U; Likungu, J; Preusse, K; Layer, G; Schild, H

    1998-02-01

    To demonstrate normal postoperative spiral CT and MRI findings and typical complications in patients with aortic repair after Stanford type A aortic dissection. 24 patients with aortic repair after Stanford type A aortic dissection were followed up by spiral CT and MRI (0.5 Tesla). Presence of persistent dissection, progressive or new dissection, proximal and distal anastomosis, periprosthetic space, supraaortic vessels, thrombosis and dilatation of the true and false lumen were evaluated. The following postoperative complications were seen: three pseudoaneurysms which developed at the proximal anastomoses of the Dacron prosthesis in two cases and at the insertion site of the reimplanted left coronary artery after implantation of a composite graft (Bentall procedure) in one case; one re-dissection; one perforation of the false lumen; periprosthetic flow in one patient after surgical repair of type A dissection by the graft inclusion technique; progressive dilatation of the false lumen in 4 cases; dilatation of the aortic root in a Marfan patient after replacement of the ascending aorta. Precise knowledge of the surgical technique performed is crucial to accurate postoperative imaging evaluation. MRI is the method of choice in the postoperative follow-up of clinically stable patients with aortic dissections.

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

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    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.

  16. MRT letter: Experimental verification of vectorial theory to determine field at the geometrical focus of a cylindrical lens.

    Science.gov (United States)

    Mohan, Kavya; Mondal, Partha Pratim

    2014-02-01

    We provide experimental evidence supporting the vectorial theory for determining electric field at and near the geometrical focus of a cylindrical lens. This theory provides precise distribution of field and its polarization effects. Experimental results show a close match (≈ 95% using χ(2)-test) with the simulation results (obtained using vectorial theory). Light-sheet generated both at low and high NA cylindrical lens shows the importance of vectorial theory for further development of light-sheet techniques. Potential applications are in planar imaging systems (such as, SPIM, IML-SPIM, imaging cytometry) and spectroscopy. Copyright © 2014 Wiley Periodicals, Inc.

  17. MRT letter: a total variation based method for 3D shape recovery of microscopic objects through image focus.

    Science.gov (United States)

    Mahmood, Muhammad Tariq

    2013-09-01

    Generally, shape from focus methods use a single focus measure to compute focus quality and to obtain an initial depth map of an object. However, different focus measures perform differently in diverse conditions. Therefore, it is hard to get accurate 3D shape based on a single focus measure. In this article, we propose a total variation based method for recovering 3D shape of an object by combining multiple depth hypothesis obtained through different focus measures. Improved performance of the proposed method is evaluated by conducting several experiments using images of synthetic and real microscopic objects. Comparative analysis demonstrates the effectiveness of the proposed approach. Copyright © 2013 Wiley Periodicals, Inc.

  18. MRT letter: localization of endogenous hydrogen peroxide by modified processes of sample preparation for transmission electron microscope in Escherichia coli.

    Science.gov (United States)

    Li, Xin; Hu, Rongliu; Zhu, Wenxue; Fan, Jinling; Pang, Xinyue; Wang, Na; Wang, Liping; Yang, Lipeng; Zhao, Chunyan; He, Chenyang

    2013-02-01

    The bacterial endogenous hydrogen peroxide (H(2)O(2)) was detected cytochemically by its reaction with cerium chloride (CeCl(3)) to produce electron-dense deposits of cerium perhydroxides. The sequence of fixation and CeCl(3) staining of H(2)O(2) in the processing of transmission electron microscope (TEM) sample preparation is crucial to the localization of endogenous H(2)O(2) in Escherichia coli. In this study, results confirmed that the process that fixation simultaneously with CeCl(3) staining provided optimum effects for H(2)O(2) localization in E. coli. The modified process of TEM provides very efficient protection for H(2)O(2) localization and more accurate quantization for the H(2)O(2) accumulation in bacterial cells. Copyright © 2012 Wiley Periodicals, Inc.

  19. MRT letter: A unified accelerated maximum likelihood technique for widefield, confocal, and super-resolution 4Pi microscopy.

    Science.gov (United States)

    Chelur K, Rasmi; Kanhirodan, Rajan; Mondal, Partha Pratim

    2015-05-01

    We propose an algorithmic technique for accelerating maximum likelihood (ML) algorithm for image reconstruction in fluorescence microscopy. This is made possible by integrating Biggs-Andrews (BA) method with ML approach. The results on widefield, confocal, and super-resolution 4Pi microscopy reveal substantial improvement in the speed of 3D image reconstruction (the number of iterations has reduced by approximately one-half). Moreover, the quality of reconstruction obtained using accelerated ML closely resembles with nonaccelerated ML method. The proposed technique is a step closer to realize real-time reconstruction in 3D fluorescence microscopy. © 2015 Wiley Periodicals, Inc.

  20. MRT letter: a fast and easy method for general fluorescent staining of cultured cells on transparent or opaque supports.

    Science.gov (United States)

    Gayoso, Manuel J

    2012-07-01

    Development of cell-based therapy entails the use of different types of materials as support for cultured cells. Some of these materials are opaque. For a general microscope study of cell cultures prepared on transparent supports, Giemsa stain with bright field microscopy is useful. With opaque supports or scaffolds, epifluorescence microscopy is necessary. The method the authors describe uses eosin Y to stain cytoplasm and DAPI to stain nuclei under fluorescence microscopy. This method provides easy and fast fluorescent staining for a general morphological study of cultured cells on transparent or opaque supports. Copyright © 2012 Wiley Periodicals, Inc.

  1. MRT letter: 3D culture of isolated cells: a fast and efficient method for optimizing their histochemical and immunocytochemical analyses.

    Science.gov (United States)

    Berenzi, Angiola; Steimberg, Nathalie; Boniotti, Jennifer; Mazzoleni, Giovanna

    2015-04-01

    The rapid development of three-dimensional (3D) culture systems and engineered cell-based tissue models gave rise to an increasing need of new techniques, allowing the microscopic observation of cell behavior/morphology in tissue-like structures, as clearly signalled by several authors during the last decennium. With samples consisting of small aggregates of isolated cells grown in suspension, it is often difficult to produce an optimal embedded preparation that can be further successfully processed for classical histochemical investigations. In this work, we describe a new, easy to use, efficient method that enables to embed an enriched "preparation" of isolated cells/small 3D cell aggregates, without any cell stress or damage. As for after tissue-embedding procedures, the cellular blocks can be further suitably processed for efficient histochemical as well as immunohistochemical analyses, rendering more informative-and attractive-studies onto 3D cell-based culture of neo-tissues. © 2015 Wiley Periodicals, Inc.

  2. MRT letter: extended depth from focus reconstruction method for stretch zone measurement in 15-5PH steel.

    Science.gov (United States)

    De Oliveira Caltabiano, Pietro Carelli Reis; Rosa, Paulo Henrique Santos; De Campos, Kamila Amato; De Oliveira Hein, Luis Rogerio

    2012-09-01

    The stretch zone width (SZW) data for 15-5PH steel CTOD specimens fractured at -150°C to + 23°C temperature were measured based on focused images and 3D maps obtained by extended depth-of-field reconstruction from light microscopy (LM) image stacks. This LM-based method, with a larger lateral resolution, seems to be as effective for quantitative analysis of SZW as scanning electron microscopy (SEM) or confocal scanning laser microscopy (CSLM), permitting to clearly identify stretch zone boundaries. Despite the worst sharpness of focused images, a robust linear correlation was established to fracture toughness (K(C) ) and SZW data for the 15-5PH steel tested specimens, measured at their center region. The method is an alternative to evaluate the boundaries of stretched zones, at a lower cost of implementation and training, since topographic data from elevation maps can be associated with reconstructed image, which summarizes the original contrast and brightness information. Finally, the extended depth-of-field method is presented here as a valuable tool for failure analysis, as a cheaper alternative to investigate rough surfaces or fracture, compared to scanning electron or confocal light microscopes. Copyright © 2012 Wiley Periodicals, Inc.

  3. MRT letter: Spatial distribution of vancomycin-induced damage in Staphylococcus epidermidis biofilm: an electron microscopic study.

    Science.gov (United States)

    Singh, Rachna; Ray, Pallab; Das, Anindita; Sharma, Meera

    2010-07-01

    This study was planned to elucidate the efficacy of antibiotics on Staphylococcus epidermidis and Staphylococcus aureus biofilms by scanning electron microscopy (SEM). Biofilms of S. epidermidis ATCC 35984 and S. aureus ATCC 29213 were grown on black, polycarbonate membranes placed on tryptic soy agar plates for 48 h at 37 degrees C, and then exposed to vancomycin or amikacin or ciprofloxacin at clinically achievable levels for 24 h at 37 degrees C. The morphology of antibiotic-treated and untreated biofilms was elucidated by SEM. SEM analysis indicated a differential affection of S. epidermidis ATCC 35984 in the center and periphery of biofilm upon treatment with vancomycin. The center of biofilm revealed damaged cells with sparse distribution, smaller size, and irregular shape, whereas cells in the periphery were unaffected. This differential distribution of susceptibility within S. epidermidis ATCC 35984 biofilms was specific for vancomycin only and was not observed on exposure to amikacin or ciprofloxacin. No such response was found in S.aureus ATCC 29213 biofilms. Thus, our study suggests a spatial distribution of vancomycin-induced damage in S. epidermidis biofilms. To our knowledge, this is the first report that indicates a differential affection of S. epidermidis in the center and periphery of biofilm upon treatment with vancomycin. Studies on the factors controlling this differential distribution could provide valuable insights into the mechanisms of antimicrobial resistance in S. epidermidis biofilms. (c) 2010 Wiley-Liss, Inc.

  4. 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.

  5. MRT letter: Real time and in situ imaging the reversible evolution of ethanol vapor condensed on mica surface.

    Science.gov (United States)

    Zhang, Donghua; Zhang, Chen; Zhang, Fuchun; Hu, Jun

    2011-06-01

    The reversible adsorption and desorption of ethanol vapor on mica surface at ambient temperature were investigated in situ with time-evolution by Vibrating Scanning Polarization Force Microscopy (VSPFM). At temperature 20 °C and relative humidity 20%, ethanol vapor condensed and formed clusters on the freshly cleaved mica. These clusters expanded to a network structure and later formed a full film shown by continuous VSPFM imaging. The film broke into pieces and desorbed completely if in unsaturated condition. The film showed different apparent heights when different biases were used in VSPFM study, indicated polarized orientation of the ethanol molecules on the mica surface. It is a process of hours for the clusters or network structures to form a film on mica, which demonstrated that vapor ethanol molecule is not so easy to precipitate on mica as ethanol molecule in liquid stage. Copyright © 2011 Wiley-Liss, Inc.

  6. 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.

  7. Revised response criteria for polycythemia vera and essential thrombocythemia: an ELN and IWG-MRT consensus project.

    Science.gov (United States)

    Barosi, Giovanni; Mesa, Ruben; Finazzi, Guido; Harrison, Claire; Kiladjian, Jean-Jacques; Lengfelder, Eva; McMullin, Mary F; Passamonti, Francesco; Vannucchi, Alessandro M; Besses, Carlos; Gisslinger, Heinz; Samuelsson, Jan; Verstovsek, Srdan; Hoffman, Ronald; Pardanani, Animesh; Cervantes, Francisco; Tefferi, Ayalew; Barbui, Tiziano

    2013-06-06

    Standardized response criteria to interpret and compare clinical trials are needed for approval of new therapeutic agents by regulatory agencies. The European LeukemiaNet (ELN) response criteria for essential thrombocythemia (ET) and polycythemia vera (PV) issued in 2009 have been widely adopted as end points in a number of recent clinical trials. However, evidence exists that they do not predict response or provide clinically relevant measures of benefit for the patients. This article presents revised recommendations for assessing response in ET and PV provided by a working group established by ELN and International Working Group-Myeloproliferative Neoplasms Research and Treatment. New definitions of complete and partial remission incorporate clinical, hematological, and histological response assessments that include a standardized symptom assessment form and consider absence of disease progression and vascular events. We anticipate that these criteria will be adopted widely to facilitate the development of new and more effective therapies for ET and PV.

  8. MRT letter: A novel tegumental gland in female imagoes of the neotropical termite Cornitermes cumulans (Isoptera, termitidae, syntermitinae).

    Science.gov (United States)

    Costa-Leonardo, Ana Maria; Haifig, Ives

    2010-10-01

    In general, the exocrine glands of social insects are structures involved in the chemical communication associated with social life. Here, we report the discovery of an unknown tegumental gland that is present in the female imagoes of Cornitermes cumulans and occurs next to the well-developed tergal glands that have previously been described. The tegumental glands release their secretion in the intersegmental membrane and are composed of bicellular units, a secretory cell and a canal cell, that are closely located to the epidermal cells in the inferior part of the eighth and ninth tergites. The ultrastructure of the glandular cells showed abundant smooth endoplasmic reticulum, suggesting that the secretion may be pheromonal, although its function is still unknown. These exocrine structures are facing the tergal glands, and we hypothesized that they act synergistically with the tergal glands to generate short-range attraction during tandem behavior. © 2010 Wiley-Liss, Inc.

  9. MRT letter: Auto-fluorescence by human alveolar macrophages after in vitro exposure to air pollution particles.

    Science.gov (United States)

    Ghio, Andrew J; Sangani, Rahul G; Brighton, Luisa E; Carson, John L

    2010-06-01

    Macrophages from smokers demonstrate an increased auto-fluorescence. Similarly, auto-fluorescence follows in vitro exposure of macrophages to cigarette smoke condensate (i.e., the particulate fraction of cigarette smoke). The composition of particles in cigarette smoke can be comparable to air pollution particles. We tested the postulate that macrophages exposed to air pollution particles could demonstrate auto-fluorescence. Healthy nonsmoking and healthy smoking volunteers (both 18-40 years of age) underwent fiberoptic bronchoscopy with bronchoalveolar lavage and alveolar macrophages isolated. Macrophages were incubated at 37 degrees C in 5% CO(2) with either PBS or 100 microg/mL particle for both 1 and 24 h. Particles included a residual oil fly ash, Mt. St. Helens volcanic ash, and ambient air particles collected from St. Louis, Missouri and Salt Lake City, Utah. At the end of incubation, 50 microL of the cell suspension was cytocentrifuged and examined at modes for viewing fluorescein isothiocyanate (FITC) and rhodamine fluorescence. Both emission source air pollution particles demonstrated FITC and rhodamine auto-fluorescence at 1 and 24 h, but the signal following incubation of the macrophages with oil fly ash appeared greater. Similarly, the ambient particles were associated with auto-fluorescence by the alveolar macrophages and this appeared to be dose-dependent. We conclude that exposure of macrophages to air pollution particles can be associated with auto-fluorescence in the FITC and rhodamine modes. c) 2009 Wiley-Liss, Inc

  10. Diagnostik fokaler Leberläsionen

    OpenAIRE

    Knuth, Brigitte

    2003-01-01

    Anhand von 466 Patienten, die im Zeitraum 2/96 bis 3/96 eine SPIO gestütze MRT-Untersuchung der Leber erhalten haben, wurde die diagnostische Leistungsfähigkeit der MRT und SPIO-MRT mit dem korrespondierenden biphasischen Spiral-CT verglichen. Dabei ergaben sich insbesondere bezüglich der Lebermetastasendiagnostik folgende Sensivitäten: CT 74,4%, native MRT 88,9%, SPIO-MRT 86,5%, Zusammenschau von MRT und SPIO-MRT 85,9%; und Spezifitäten: CT 49,6%, native MRT 62,8%, SPIO-MRT 62,5%, Zusammensc...

  11. Ljuboi vizit polezen, jesli sluzhit razvitiju dobrosossedskihh otnoshenii

    Index Scriptorium Estoniae

    2008-01-01

    Viimastel valimistel Venemaa presidendiks pürginud Venemaa demokraatliku partei esimees Andrei Bogdanov külastas Sillamäed, kus kohtus kontserni Silmet Grupp juhi Tiit Vähi ning parlamendiliikme Valeri Korbiga

  12. Magnetic resonance imaging in syringomyelia - follow-up studies after syringosubarachnoidal shunting with clinical correlation. MRT bei Syringomyelie - Verlaufskontrollen nach syringosubarachnoidalen Shuntoperationen mit klinischer Korrelation

    Energy Technology Data Exchange (ETDEWEB)

    Kahn, T.; Moedder, U. (Duesseldorf Univ. (Germany). Inst. fuer Diagnostische Radiologie); Roosen, N.; Lumenta, C.B.; Bock, W.J. (Duesseldorf Univ. (Germany). Neurochirurgische Klinik); Steinmetz, H. (Duesseldorf Univ. (Germany). Neurologische Klinik)

    1991-11-01

    In 8 patients with syringomyelia, MR long-term follow-ups (observation period 25-46 months) were done after syringosubrachnoidal shunt operations. MR showed directly after surgery in 6 cases an extensive collapse of the syringomyelias and in 2 cases a lesser reduction of the diameter of the syrinx. During the subsequent course the size of the cavities increased again in 3 cases. The size of the syrinx visualised by MR did not correlate with the clinical status during the follow-up studies. This seems to point to an insufficient representation of the disease process by the morphological visualisation of the size of the syrinx. (orig.).

  13. Anthracycline-induced cardiotoxicity: Cardiac MRI after treatment for childhood cancer; Anthrazyklin-induzierte Kardiotoxizitaet: MRT des Herzens bei Kindern und Jugendlichen mit malignen Erkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Oberholzer, K.; Kunz, R.P.; Thelen, M. [Johannes-Gutenberg-Univ. Mainz (Germany). Klinik und Poliklinik fuer Radiologie; Dittrich, M. [Johannes-Gutenberg-Univ. Mainz (Germany). Kinderklinik und Kinderpoliklinik

    2004-09-01

    Purpose: Quantification of left and right ventricular function using MRI in young cancer patients treated with cardiotoxic anthracyclines. Materials and Methods: Twenty-eight patients (mean age 16.4 years) underwent cardiac MRI at 1.5 T. The study protocol consisted of morphologic T2-weighted images with fat suppression and cine steady-state free precession sequences (SSFP) for functional analysis. Seven patients were examined at the end of chemotherapy, two of them also repeatedly during therapy, and 21 patients following an average period of three years after finishing chemotherapy (range one month - 20 years). Results: The end-systolic volume index increased and the ejection fraction of the left and right ventricle decreased during anthracycline therapy. Two of seven patients showed a myocardial edema at the end of the therapy. In 15 of all 28 patients, the left ventricular ejection fraction was reduced to less than 55% (minimum 44%). No clinical signs of cardiac insufficiency or cardiomyopathy were observed. Conclusion: MRI is able to detect acute as well as chronic subclinical cardiotoxic effects of anthracyclines. Impairment of the right ventricular function should be considered in the diagnosis of anthracycline-induced cardiomyopathy. (orig.)

  14. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-06-15

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

  16. 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.)

  17. MR implant labelling and its use in clinical MRI practice; MR-Implantatkennzeichnungen und ihre Anwendung in der klinischen MRT-Praxis

    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)

    2015-08-15

    Before a magnetic resonance imaging (MRI) examination, implants in patients must be cleared for MR safety in order to exclude the risk of possible severe injuries and implant malfunction in an MR environment. The general contraindication for measurements of patients with implants still applies; however, in the recent past a way has been found to legally circumvent this contraindication. For this purpose special conditions are required: explicit implant identification and the original manufacturer's labelling are necessary, the required conditions for conditionally MR safe implants must be assured and a risk-benefit analysis with appropriate explanation to the patient has to be performed. This process can be very complex as the implants are often poorly documented and detailed information on the implant MR labelling is also often outdated or not easy to interpret. This article provides information about legal and normative principles of MR measurement of patients with implants. The possible physical interactions with implants will be briefly dealt with as well as possible strategies for better identification and investigation of implants and MR labelling. General approaches for minimizing the risk will be discussed using some examples. The second part deals with the content of MR implant labelling and the current test standards. Furthermore, the additional information from the operating instructions of the MR scanner that are necessary for the interpretation of the MR implant labelling, will be explained. The article concludes with an explanation of the current pattern for MR labelling of implants from the U.S. Food and Drug Administration (FDA) and an exemplary application. (orig.) [German] Implantate in Patienten muessen vor einer MR-Untersuchung auf MR-Sicherheit abgeklaert werden, um moegliche z. T. schwere Verletzungen und Implantatfehlfunktionen in einer MR-Umgebung weitestgehend auszuschliessen. Es gilt unveraendert die generelle Kontraindikation von Messungen von Patienten mit Implantaten. In juengerer Vergangenheit ist jedoch ein Weg geschaffen worden, diese Kontraindikation legal zu umgehen. Hierfuer sind spezielle Voraussetzungen noetig: Eindeutige Implantatidentifikation und Vorlage der originalen Herstellerkennzeichnung, Gewaehrleistung der geforderten Bedingungen bei ''bedingt MR-sicheren'' Implantaten und Restrisiko-Nutzen-Analyse mit entsprechender Aufklaerung. Dieser Prozess ist u. U. sehr aufwendig, da die Implantate haeufig schlecht dokumentiert und die Detailinformationen der Implantatkennzeichnung ebenfalls nicht selten veraltet oder nicht einfach zu interpretieren sind. Diese Arbeit informiert ueber rechtliche und normative Grundlagen der Messung von Patienten mit Implantaten. Es werden kurz moegliche physikalische Wechselwirkungen mit Implantaten angerissen, moegliche Strategien zur besseren Identifikation und Recherche von Implantaten und ihrer MR-Kennzeichnung aufgezeigt und allgemeine Ansaetze zur Risikominimierung an Beispielen diskutiert. Der zweite Teil geht auf die Inhalte von MR-Implantatkennzeichnungen ein und zeigt die aktuellen Pruefstandards auf. Es werden die fuer die Interpretation von MR-Implantatkennzeichnungen notwendigen Zusatzinformationen aus den Betriebsanleitungen der MR-Scanner erlaeutert. Abschliessend folgen die Erklaerung der aktuellen Muster-MR-Kennzeichnung von Implantaten der FDA (US Food and Drug Administration) und eine exemplarische Anwendung. (orig.)

  18. 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.

  19. Patterns of delayed-enhancement in MRI of ischemic and non-ischemic cardiomyopathies; Muster der spaeten Kontrastmittelanreicherung in der MRT bei ischaemischen und nicht-ischaemischen Kardiomyopathien

    Energy Technology Data Exchange (ETDEWEB)

    Stork, A.; Bansmann, P.M.; Koops, A.; Adam, G. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Universitaetsklinikum Hamburg-Eppendorf (Germany); Muellerleile, K.; Meinertz, T. [Universitaeres Herzzentrum, Universitaetsklinikum Hamburg-Eppendorf (Germany); Lund, G.K. [Kardiovaskulaere Bildgebung, Roentgeninstitut Duesseldorf (Germany)

    2007-01-15

    Contrast-enhanced MRI using the delayed-enhancement technique (DE-MRI) is widely applied in the clinical work-up of myocardial diseases. Myocardial diseases of varying etiology result in myocardial changes, such as necrosis, fibrosis, edema and metabolite deposition, which can be visualized by DE-MRI. Acute and chronic ischemic diseases based on a coronary artery disease as well as non-ischemic cardiomyopathies display DE. Cardiomyopathies often show a characteristic enhancement pattern. While ischemic lesions are localized in the subendocardium, non-ischemic cardiomyopathies often display an intramyocardial or subepicardial pattern. The typical pattern for dilated cardiomyopathies is band-like and intramyocardial with septal involvement. Arrhythmogenic right-ventricular dysplasias/cardiomyopathies are frequently associated with right-ventricular DE. In the case of amyloid cardiomyopathies which are often restrictive cardiomyopathies, subendocardial and circular DE is typically observed. Hypertrophic cardiomyopathies display patchy intramyocardial DE usually in the anteroseptal region. Acute myocarditis is typically accompanied by intramyocardial or subepicardial DE affecting the lateral wall. In the case of chronic myocarditis, intramyocardial or subepicardial DE is observed most frequently. Cardiac sarcoidosis typically entails patchy subepicardial DE with right- and left-ventricular involvement. Since there is an overlap between the enhancement patterns of cardiomyopathies, the diagnostic accuracy of DE-MRI is limited and the diagnosis must be based on additional clinical and MRI findings. The amount of DE often corresponds with cardiac functional parameters as well as with the frequency of cardiac events so that DE-MRI may be useful for risk stratification. Furthermore, DE-MRI can be helpful in the planning and evaluation of myocardial biopsies and electrophysiological examinations. (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. 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)

  2. 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.)

  3. MRI after patellar dislocation. Assessment of risk factors and injury to the joint; MRT nach Patellaluxation. Quantifizierung der Risikofaktoren und Beschreibung der Folgeschaeden

    Energy Technology Data Exchange (ETDEWEB)

    Diederichs, G. [Charite Universitaetsmedizin, Berlin (Germany). Radiologie; Scheffler, S. [Charite Universitaetsmedizin, Berlin (Germany). Zentrum fuer Muskuloskeletale Chirurgie; Chirurgisch Orthopaedischer PraxisVerbund, Berlin (Germany)

    2013-07-15

    Patellar dislocation is the lateral displacement of the patella from the femoral trochlea. Affected individuals typically have underlying anatomic risk factors of variable magnitude, which, in conjunction with leg rotation, cause the event. Magnetic resonance imaging (MRI) permits straightforward diagnosis of the typical features of recent patellar dislocation: contusion edema of the inferomedial patella and the lateral femoral condyle as well as rupture of the medial patellofemoral ligament. In case of concomitant osteochondral injury, early surgical refixation may be indicated, depending on the size. After a first dislocation, which can damage the capsuloligamentous stabilizers, subjects may sustain further dislocations or even develop chronic patellofemoral instability, depending on the presence and severity of anatomic variants. A wide range of conservative and surgical treatments are available. While a first patellar dislocation is often treated conservatively, surgical strategies after a second dislocation depend on the pattern of injury and the severity of underlying anatomic risk factors. The most relevant predisposing variants are trochlear dysplasia, patella alta, and an abnormal tibial tubercle to trochlear groove distance (TT-TG). The radiologist's report should give a quantitative estimate of both the injuries resulting from dislocation and the underlying anatomic risk factors. An accurate characterization of the individual pathomechanism is crucial for tailoring treatment. (orig.)

  4. Reliability measures of a computer system with priority to PM over the H/W repair activities subject to MOT and MRT

    Directory of Open Access Journals (Sweden)

    Ashish Kumar

    2015-01-01

    Full Text Available This paper concentrates on the evaluation of reliability measures of a computer system of two-identical units having independent failure of h/w and s/w components. Initially one unit is operative and the other is kept as spare in cold standby. There is a single server visiting the system immediately whenever needed. The server conducts preventive maintenance of the unit after a maximum operation time. If server is unable to repair the h/w components in maximum repair time, then components in the unit are replaced immediately by new one. However, only replacement of the s/w components has been made at their failure. The priority is given to the preventive maintenance over repair activities of the h/w. The time to failure of the components follows negative exponential distribution whereas the distribution of preventive maintenance, repair and replacement time are taken as arbitrary. The expressions for some important reliability measures of system effectiveness have been derived using semi-Markov process and regenerative point technique. The graphical behavior of the results has also been shown for a particular case.

  5. Current status of magnetic resonance imaging in diagnostics of the ankle - a critical evaluation. Aktueller Stand der Magnetresonanztomographie (MRT) in der Diagnostik der Sprunggelenke - eine kritische Wertung

    Energy Technology Data Exchange (ETDEWEB)

    Maeurer, J. (Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, FU Berlin (Germany)); Mueller, F. (Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, FU Berlin (Germany)); Vogl, T.J. (Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, FU Berlin (Germany)); Hosten, N. (Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, FU Berlin (Germany)); Langer, R. (Strahlenklinik und Poliklinik, Klinikum Rudolf Virchow, Standort Wedding, FU Berlin (Germany)); Felix, R.

    1994-05-01

    Anatomical preparations of the ankle were examined by T[sub 1]-weighted SE-sequences in three planes to identify normal topography. The current status of magnetic resonance imaging (MRI) was assessed and illustrated by image examples. Together with conventional radiography, MRI yields relevant information for therapy planning. This technique allows accurate staging of traumatic and degenerative involving the soft tissues of the joint, including tendons and ligaments. MRI clearly delineates joint fluid, osteochondral abnormalities, and is helpful in the diagnosis of inflammatory changes of the synovia and bone marrow. Furthermore, it is the modality of choice for evaluating tissue neoplasma. Its advantages are not only the detection of the process and definition of its extent, but also the determination of local soft-tissue infiltration. (orig.)

  6. Pseudotumor cerebri: quantitative in-vivo measurements of markers of intracranial hypertension; Pseudotumor cerebri: Quantitative Normalwerte anatomischer Kennstrukturen im kraniellen MRT

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    Rohr, A.; Riedel, C.; Reimann, G.; Alfke, K.; Jansen, O. [Neuroradiologie, UK-SH Campus Kiel (Germany); Hedderich, J. [Medizinische Informatik und Statistik, UK-SH Campus Kiel (Germany)

    2008-10-15

    Purpose: intracranial hypertension can change the morphology of anatomical structures that are critical in the evaluation of pseudotumor syndromes. The purpose of our study was to establish the normal range of such markers of intracranial hypertension and to consider a dependency on sex, age and body-mass index (BMI). Materials and methods: 123 persons without signs or symptoms of intracranial hypertension (63 females, 60 males, 18 - 86 years old, mean 49.5 SD 17.8 years, mean BMI 25.3 SD 42) were prospectively enrolled and MRI was performed at 3T. A STIR sequence in the coronal plane was used to measure the width of the optic nerve, the perioptic fluid rim and the total optic nerve sheath diameter in 4 different locations behind the eyeball. The height and width of the pituitary and Meckel's cave were also measured and the area was calculated. Results: the mean width of the optic nerve sheath narrows significantly from anterior (mean 5.3 SD 0.6 mm) to posterior (mean 4.1 SD 0.4 mm), as does the perioptic fluid rim (mean 1.4 SD 0.3 mm vs. mean 1.0 SD 0.2 mm) and - to a lesser extent - the optic nerve itself (mean 2.4 SD 0.4 mm vs. mean 2 SD 0.3 mm, p = 0.000 for all). There was no statistically relevant correlation of the width of the optic nerve sheath with age. The coronal area of Meckel's cave was independent of sex, age or BMI (mean 39 SD 9.3 mm{sup 2}). The height of the pituitary differed little in women (mean 4.4 SD 0.9 mm) and men (mean 4.2 SD 0.8 mm), but we found a significant negative correlation with age in women only (r = -0.38, p = 0.01). (orig.)

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

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    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.)

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

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    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.)

  9. Cardiac MRI in addition to MR angiography: a longitudinal study in vascular risk patients; Kardiale MRT als Ergaenzung zur MR-Angiografie: Eine longitudinale Studie bei vaskulaeren Risikopatienten

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    Seeger, A.; Grimm, F.; Fenchel, M.; Kramer, U.; Doering, J.S.; Klumpp, B.; Claussen, C.D.; Miller, S. [Abt. fuer Radiologische Diagnostik, Eberhard-Karls-Univ. Tuebingen (Germany); Scheule, A. [Abt. fuer Herz-, Thorax- und Gefaesschirurgie, Eberhard-Karls-Univ. Tuebingen (Germany); May, A.E. [Abt. fuer Kardiologie, Eberhard-Karls-Univ. Tuebingen (Germany)

    2008-05-15

    Purpose: the aim of the study was to assess the feasibility and additional diagnostic information of cardiac MRI as a supplement to state-of-the-art MR angiography (MRA) in the case of vascular risk patients. Therefore, the prevalence of delayed myocardial enhancement (DE) was determined in patients suffering from peripheral artery disease (PAD) and a clinical follow-up was evaluated after 2 years. Materials and method: 87 consecutive patients (ages 66 {+-} 10 years, 67 males) with symptomatic peripheral arterial occlusive disease (n = 68) or abdominal aortic aneurysm (n = 19) were examined using delayed cardiac enhancement (DE) within the clinical indication of MRA at a 1.5T system. A follow-up examination was carried out two years later (24 months {+-} 4 months) with regards to cardiac events (cardiac death, myocardial infarction or acute coronary syndrome, heart insufficiency, coronary revascularization). Results: in total, 40/87 patients had myocardial infarctions shown in MRI (46%). In 25 patients (29%), the myocardial infarction was already known, while in 15 patients (17%) an occult progressing infarction was diagnosed (38% of the myocardial infarcts). Follow-up data was able to be obtained after 2 years for 82 patients. 15 patients had a major cardiac event during the follow-up period, and 10 (67%) of them already showed DE in the MRI. In the group with occult progressing infarctions, cardiac events occurred in 40% (6/15 patients, cardiac death n = 1, ischemia n = 4, heart insufficiency n = 1, bypass n = 1), in patients with known infarction in 17% (4/23 patients, cardiac death n = 1, ischemia n = 3, bypass n = 2) and in 11% of patients without myocardial scars (5/44 patients, cardiac death n = 1, ischemia n = 2, heart insufficiency n = 2). (orig.)

  10. MRI evaluation of cardiomyopathies. A guide-line for the physician; MRT bei Kardiomyopathien. Eine praxisorientierte Anleitung zur Untersuchung und Befundung

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    Haegele, J.; Hunold, P.; Barkhausen, J. [Universitaetsklinikum Schleswig-Holstein, Luebeck (Germany). Klinik fuer Radiologie und Nuklearmedizin

    2012-03-15

    Within last decade MRI emerged as an important diagnostical tool in cardiac disease. Due to the excellent soft-tissue contrast MRI adds essential information to other diagnostic procedures, and allows correct diagnosis in different cardiomyopathies. However, knowledge of differential diagnosis and individually adapted MRI-protocols are a precondition to distinguish cardiomyopathies from other cardiac diseases. This paper is understood as a review of common findings in cardiomyopathies and the most important differential diagnosis and shall serve as a simple guideline for the physician. (orig.)

  11. 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

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    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.)

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

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    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.

  13. Morphometric analysis of the temporomandibular joint with MRI in 320 joints; Morphometrische Analyse des Kiefergelenkes anhand von 320 Gelenken mit der MRT

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    Lemke, A.J.; Felix, R. [Charite, Univ. Berlin, Campus Virchow-Klinikum, Klinik fuer Strahlenheilkunde (Germany); Griethe, M.; Peroz, I.; Lange, K.P. [Charite, Univ. Berlin, Campus Virchow-Klinikum, Zentrum fuer Zahnmedizin, Abt. fuer zahnaerztliche Prothetik und Alterszahnmedizin (Germany)

    2005-02-01

    Purpose: to compare several morphometric parameters in MRI with the functional status of the articular disc in a large patient group suffering from internal derangement (ID) of the temporomandibular joint (TMJ). Materials and methods: in a retrospective study, 320 analyzable high resolution MRI examinations of the TMJs obtained in a 1.5 T unit were evaluated in 184 patients with clinically suspected ID. The analysis included the anatomical structures and a number of morphometric parameters previously described in the literature. The parameters were compared with the position of the articular disc. Results: the disc position was categorized as ''normal'' (NDP, 21.9%, n = 70), ''anterior displacement with reduction on opening'' (AMR, 51.6%, n = 165) and ''anterior displacement without reduction on opening'' (AOR, 26.6%, n = 85). With increasing disc displacement, significant configurational changes of the disc were observed. Disc displacement was associated with changes of the condyle consisting of increasing deformity and other degenerative changes. A large tuberculum and marked inclination of the eminence can be seen as predisposition for the development of ID. With increasing severity of the ID, the position of the condyle moved from a centric position of the condylar center to an excentric (dorsal and cranial) position. Conclusion: MRI demonstrated that increasing disc displacement is associated with changes of the disc, condyles and condylar position in the fossa. (orig.)

  14. 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

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    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).

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

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    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.)

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

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    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.)

  17. Epiphyseal dysplasia of the hip. Diagnosis and differential diagnosis with MRI. Epiphysaere Dysplasie des Hueftgelenks, Diagnostik und Differentialdiagnostik mit der MRT

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    Grimm, J. (Univ. Mainz, Orthopaedische Klinik und Poliklinik (Germany)); Just, M. (Univ. Mainz, Klinik mit Poliklinik fuer Radiologie (Germany))

    1992-07-01

    Sixteen hip joints of eight patients with multiple epiphyseal dysplasia were examined by clinical investigation, plain films and by magnetic resonance imaging (MRI), using T[sub 1]- and T[sub 2]-weighted images and gradient echoes. MRI is useful in demonstrating the congruity of the joint, in the changes of the epiphyseal signal intensities and the epiphyseal line. Individual changes of the signal intensity patterns on T[sub 1]- and T[sub 2]-weighted scans are described. Although MRI exhibits a variety of patterns in different patients, a clearcut differentiation from Legg-Calve-Perthes' disease is possible. (orig.).

  18. [The MRT of focal liver lesions: the value of gadolinium-enhanced dynamic studies of the whole organ with a fast 3D-turbo-gradient echo sequence].

    Science.gov (United States)

    Pauleit, D; Textor, J; Conrad, R; Flacke, S; Gieseke, J; Born, M; Bachmann, R; Kreft, B; Schild, H

    1999-04-01

    To determine the value of a dynamic Gd-enhanced ultrafast T1-weighted 3D-turbo-gradient-echo sequence (3D-TFE) in the detection and characterization of focal liver lesions. 51 patients with 124 focal liver lesions (35 hemangiomas, 30 HCC, 24 metastases, 22 cysts, 5 FNH/adenoma, 8 other lesions) were examined using a 1.5 T system. The dynamic 3D-TFE sequence, achieving 40 slices with a thickness of 4.5 mm in a 17-s breath-hold, was compared with a fat-suppressed T2-weighted fast-spin-echo sequence (TSE SPIR), unenhanced and Gd-enhanced T1-weighted spin-echo sequences (SE), and a T1-weighted gradient-echo sequence (FFE). On 3D-TFE images more lesions (107/124) were identified than on T1-weighted SE (101/124) and T1-weighted FFE images (106/124), but less compared to T2-weighted TSE SPIR images (115/124). The 3D-TFE-sequence provided additional information in 65/107 (61%) detected lesions by delineating the dynamic enhancement pattern, most valuable in patients with HCCs in 90%. On dynamic 3D-TFE images more lesions could be depicted than on conventional T1-weighted SE and T1-weighted FFE images. Visualization of the dynamic enhancement pattern provided additional information for tumor characterization in 61% of the detected lesions on the 3D-TFE images.

  19. 3D-visualization by MRI for surgical planning of Wilms tumors; 3-D-Visualisierung in der MRT zur Operationsplanung von Wilms-Tumoren

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    Schenk, J.P.; Wunsch, R.; Jourdan, C.; Troeger, J. [Universitaetsklinik Heidelberg (Germany). Abteilung Paediatrische Radiologie; Waag, K.-L.; Guenther, P. [Universitaetsklinik Heidelberg (Germany). Abteilung Kinderchirurgie; Graf, N. [Universitaetsklinik Homburg (Germany). Abteilung Paediatrische Haematologie und Onkologie; Behnisch, W. [Universitaetsklinik Heidelberg (Germany). Abteilung Paediatrische Haematologie und Onkologie

    2004-10-01

    Purpose: To improve surgical planning of kidney tumors in childhood (Wilms tumor, mesoblastic nephroma) after radiologic verification of the presumptive diagnosis with interactive colored 3D-animation in MRI. Materials and Methods: In 7 children (1 boy, 6 girls) with a mean age of 3 years (1 month to 11 years), the MRI database (DICOM) was processed with a raycasting-based 3D-volume-rendering software (VG Studio Max 1.1/Volume Graphics). The abdominal MRI-sequences (coronal STIR, coronal T1 TSE, transverse T1/T2 TSE, sagittal T2 TSE, transverse and coronal T1 TSE post contrast) were obtained with a 0.5T unit in 4-6 mm slices. Additionally, phase-contrast-MR-angiography was applied to delineate the large abdominal and retroperitoneal vessels. A notebook was used to demonstrate the 3D-visualization for surgical planning before surgery and during the surgical procedure. Results: In all 7 cases, the surgical approach was influenced by interactive 3D-animation and the information found useful for surgical planning. Above all, the 3D-visualization demonstrates the mass effect of the Wilms tumor and its anatomical relationship to the renal hilum and to the rest of the kidney as well as the topographic relationship of the tumor to the critical vessels. One rupture of the tumor capsule occurred as a surgical complication. For the surgeon, the transformation of the anatomical situation from MRI to the surgical situs has become much easier. Conclusion: For surgical planning of Wilms tumors, the 3D-visualization with 3D-animation of the situs helps to transfer important information from the pediatric radiologist to the pediatric surgeon and optimizes the surgical preparation. A reduction of complications is to be expected. (orig.)

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

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    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.

  1. A dynamic prognostic model to predict survival in primary myelofibrosis: a study by the IWG-MRT (International Working Group for Myeloproliferative Neoplasms Research and Treatment).

    Science.gov (United States)

    Passamonti, Francesco; Cervantes, Francisco; Vannucchi, Alessandro Maria; Morra, Enrica; Rumi, Elisa; Pereira, Arturo; Guglielmelli, Paola; Pungolino, Ester; Caramella, Marianna; Maffioli, Margherita; Pascutto, Cristiana; Lazzarino, Mario; Cazzola, Mario; Tefferi, Ayalew

    2010-03-04

    Age older than 65 years, hemoglobin level lower than 100 g/L (10 g/dL), white blood cell count greater than 25 x 10(9)/L, peripheral blood blasts 1% or higher, and constitutional symptoms have been shown to predict poor survival in primary myelofibrosis (PMF) at diagnosis. To investigate whether the acquisition of these factors during follow-up predicts survival, we studied 525 PMF patients regularly followed. All 5 variables had a significant impact on survival when analyzed as time-dependent covariates in a multivariate Cox proportional hazard model and were included in 2 separate models, 1 for all patients (Dynamic International Prognostic Scoring System [DIPSS]) and 1 for patients younger than 65 years (age-adjusted DIPSS). Risk factors were assigned score values based on hazard ratios (HRs). Risk categories were low, intermediate-1, intermediate-2, and high in both models. Survival was estimated by the HR. When shifting to the next risk category, the HR was 4.13 for low risk, 4.61 for intermediate-1, and 2.54 for intermediate-2 according to DIPSS; 3.97 for low risk, 2.84 for intermediate-1, and 1.81 for intermediate-2 according to the age-adjusted DIPSS. The novelty of these models is the prognostic assessment of patients with PMF anytime during their clinical course, which may be useful for treatment decision-making.

  2. International Working Group (IWG) consensus criteria for treatment response in myelofibrosis with myeloid metaplasia, for the IWG for Myelofibrosis Research and Treatment (IWG-MRT).

    Science.gov (United States)

    Tefferi, Ayalew; Barosi, Giovanni; Mesa, Ruben A; Cervantes, Francisco; Deeg, H Joachim; Reilly, John T; Verstovsek, Srdan; Dupriez, Brigitte; Silver, Richard T; Odenike, Olatoyosi; Cortes, Jorge; Wadleigh, Martha; Solberg, Lawrence A; Camoriano, John K; Gisslinger, Heinz; Noel, Pierre; Thiele, Juergen; Vardiman, James W; Hoffman, Ronald; Cross, Nicholas C P; Gilliland, D Gary; Kantarjian, Hagop

    2006-09-01

    Myelofibrosis with myeloid metaplasia (MMM) is a clinicopathologic entity characterized by stem cell-derived clonal myeloproliferation, ineffective erythropoiesis, extramedullary hematopoiesis, and bone marrow fibrosis and osteosclerosis. Patients with MMM have shortened survival and their quality of life is compromised by progressive anemia, marked hepatosplenomegaly, and severe constitutional symptoms including cachexia. After decades of frustration with ineffective therapy, patients are now being served by promising treatment approaches that include allogeneic hematopoietic stem cell transplantation and immunomodulatory drugs. Recent information regarding disease pathogenesis, including a contribution to the myeloproliferative disorder phenotype by a gain-of-function JAK2 mutation (JAK2(V617F)), has revived the prospect of targeted therapeutics as well as molecular monitoring of treatment response. Such progress calls for standardization of response criteria to accurately assess the value of new treatment modalities, to allow accurate comparison between studies, and to ensure that the definition of response reflects meaningful health outcome. Accordingly, an international panel of experts recently convened and delineated 3 response categories: complete remission (CR), partial remission (PR), and clinical improvement (CI). Bone marrow histologic and hematologic remissions characterize CR and CR/PR, respectively. The panel agreed that the CI response category is applicable only to patients with moderate to severe cytopenia or splenomegaly.

  3. Effect of random structure on permeability and heat transfer characteristics for flow in 2D porous medium based on MRT lattice Boltzmann method

    Science.gov (United States)

    Yang, PeiPei; Wen, Zhi; Dou, RuiFeng; Liu, Xunliang

    2016-08-01

    Flow and heat transfer through a 2D random porous medium are studied by using the lattice Boltzmann method (LBM). For the random porous medium, the influence of disordered cylinder arrangement on permeability and Nusselt number are investigated. Results indicate that the permeability and Nusselt number for different cylinder locations are unequal even with the same number and size of cylinders. New correlations for the permeability and coefficient b‧Den of the Forchheimer equation are proposed for random porous medium composed of Gaussian distributed circular cylinders. Furthermore, a general set of heat transfer correlations is proposed and compared with existing experimental data and empirical correlations. Our results show that the Nu number increases with the increase of the porosity, hence heat transfer is found to be accurate considering the effect of porosity.

  4. [Radial diagnosis MRT and MSCT in assessing the outcomes of surgical correction for complicated congenital heart defects: discordant atrioventricular connections with double outlet right ventricle].

    Science.gov (United States)

    Mershina, E A; Frolova, Iu V; Seliavko, Iu A; Sinitsyn, V E

    2012-01-01

    Discordant atrioventricular connection with double outlet right ventricle is a rare complicated congenital heart defect (CHD) requiring accurate diagnosis and appropriate correction. Magnetic resonance imaging (MRI) and multiple spiral computed tomography (MSCT) were used to assess long-term outcomes of the «classical» repair of the double outlet right ventricle in a patient presenting with discordant atrioventricular connection. Using a modified segmental approach provided all necessary anatomical evidence concerning the condition of the heart, major vessels, and an extracardiac pulmonary valve-containing conduit. MSCT made it possible to evaluate the degree of calcinosis and stenosis of the conduit and to visualize the coronary arteries. MRI was employed to assess the pressure gradient at the level of stenosis of the conduit, the relationship between the pulmonary and systemic circulation, transvalvular regurgitation, and ventricular contractility. Comprehensive use of present-day tomographic methods of imaging made it possible to obtain complete anatomical and functional information about the condition of the heart, vessels, extracardiac vascular transplant, as well as to reveal complications and determine the indications for a repeat operative intervention.

  5. MRT letter: high resolution SEM imaging of nano-architecture of cured urea-formaldehyde resin using plasma coating of osmium.

    Science.gov (United States)

    Park, Byung-Dae; Singh, Adya P; Nuryawan, Arif; Hwang, Kiju

    2013-11-01

    Nanoarchitecture of cured urea-formaldehyde (UF) resins was examined with a field-emission scanning electron microscope (FE-SEM) after coating samples with osmium, which is considered to produce particles of considerably smaller size compared to other metal coatings used in SEM studies. This method enabled comparison of the nanoarchitecture of UF resins of low (1.0) and high (1.6) formaldehyde/urea (F/U) mole ratios to be made, based on imaging of extremely small size particles as part of UF resin architecture, not described before. Imaging revealed presence of relatively large globular particles (148.084-703.983 nm size range) as well as smaller substructures (28.004-39.604 nm size range) as part of the architecture of 1.0-mole UF resin. Globular particles were also present in 1.6 mole UF resin, but of considerably smaller size (14.760-50.269 nm). The work presented demonstrates usefulness of osmium coating in unraveling the intricacies of the nanostructural organization of cured UF resins, prompting wider application of this immensely useful but grossly underutilized metal coating type in high resolution SEM examination of biological and materials samples. Copyright © 2013 Wiley Periodicals, Inc.

  6. 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.

  7. Detection and evaluation of initial cartilage pathology in man: A comparison between MRT, arthroscopy and near-infrared spectroscopy (NIR) in their relation to initial knee pain.

    Science.gov (United States)

    Hofmann, Gunther O; Marticke, Julia; Grossstück, Ralph; Hoffmann, M; Lange, Matthias; Plettenberg, Holger K W; Braunschweig, Rainer; Schilling, Oliver; Kaden, Ingmar; Spahn, Gunter

    2010-02-01

    MRI and arthroscopy are important methods in the evaluation of cartilage pathology. But frequently initial changes of cartilage in combination with chronic knee pain cannot be detected by employing these two methods. Better diagnostic tools for the detection of the early stages of osteoarthritis (OA) are required. The objective of this study was to show that near-infrared spectroscopy (NIRS) can be incorporated into routine arthroscopy to improve detection and assessment of the initial cartilage pathology. Furthermore correlations between findings in MRI, arthroscopy and NIRS in patients with initial symptoms of OA have studied. Patients (n=21, 12 women, 9 men, age: 15-59 years, mean 34.19 years) with knee pain lasting for at least half a year without any trauma of the knee in their history were interviewed (body weight, smoking behaviour) and clinically evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS). Also serum parameters (cholesterol, lipids) were analysed, conventional X-rays in three directions (evaluated according to Kellgren and Lawrence) and MRI (evaluation of cartilage damage according to the ICRS-score) were performed preoperatively in all patients. During subsequent arthroscopy cartilage damage was evaluated according to the ICRS-score. In addition the spectral reflection of cartilage was investigated in all knees using a special micro-glass-fiber probe in the near-infrared light region (spectral range between 1150 and 1475nm). To characterize relations between the investigated parameters the Spearman's rank correlation coefficient was used. Inter-observer variance was calculated employing the Cohens-Kappa-test. MRI demonstrated a strong inter-observer variance with no significant correlations to other parameters. The same was observed for arthroscopic findings. Only NIRS showed significant correlations with three out of five KOOS subscores. Within the general parameters only smoking behaviour showed a significant correlation with two of the KOOS-scores. NIRS therefore seemed to be a sensitive diagnostic tool in detection of initial pathology in human cartilage. The additional necessary time for the spectroscopic investigation as part of the routine arthroscopy ranged between 3 and 7min (mean: 4min 18s). Particularly for early-stage cartilage lesions (ICRS 0/I) MRI and arthroscopy have rather low predictive value. The inter-observer variance is very high (Cohens-Kappa<0.4). Correlations found between NIRS and KOOS suggest that NIRS potentially can be used for detection of initial cartilage pathology and may be helpful in the evaluation of the benefit of different medical or surgical interventions at early-stage of articular cartilage damage. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

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

    Science.gov (United States)

    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

    2013-03-28

    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 advanced features. These variants, henceforth collectively referred to as advanced SM for the purposes of this report, are typically characterized by organ damage and shortened survival duration. In contrast to indolent SM, in which symptoms are usually managed by noncytotoxic antimediator therapy, cytoreduction is usually necessary for disease control in advanced SM. Unfortunately, current drug treatment of these patients rarely results in complete clinical and histopathologic remissions or improved survival time. Previously defined response criteria were adapted to the heterogeneous presentations of advanced SM and the limited effects of available drugs. However, recent advances in understanding the molecular pathogenesis of SM and the corresponding prospect in targeted therapy make it a priority to modify these criteria. Our current study is the product of an international group of experts and summarizes the challenges in accomplishing this task and forwards a new proposal for response criteria, which builds on prior proposals and should facilitate response evaluation in clinical trials.

  9. Antecedentes y función literaria del sueño de Eneas y Andrómaca: Verg., Aen . II 268-295 y Sen., Troad . 438-488

    Directory of Open Access Journals (Sweden)

    Santiago López Moreda

    1998-12-01

    Full Text Available Traditionally it is said that the source of Seneca's tragedies is Euripides. The coincidence with the subjects corroborates it. However, the nearness between tragedy and epic, the Trojan cycle that the first Latin writers of tragedy take for themselves, and, above all, the poetics of artistic effect based on the narrative structure and the lexical and syntactic patterns show that, at least in this passage, Seneca's source is Vergil, who is also the receiver and transmitter of ancient epic and the Greek and Roman tragedy.

  10. On the verge of a respiratory-type panic attack: Selective activations of rostrolateral and caudoventrolateral periaqueductal gray matter following short-lasting escape to a low dose of potassium cyanide.

    Science.gov (United States)

    Müller, Cláudia Janaina Torres; Quintino-Dos-Santos, Jeyce Willig; Schimitel, Fagna Giacomin; Tufik, Sérgio; Beijamini, Vanessa; Canteras, Newton Sabino; Schenberg, Luiz Carlos

    2017-04-21

    Intravenous injections of potassium cyanide (KCN) both elicit escape by its own and facilitate escape to electrical stimulation of the periaqueductal gray matter (PAG). Moreover, whereas the KCN-evoked escape is potentiated by CO 2 , it is suppressed by both lesions of PAG and clinically effective treatments with panicolytics. These and other data suggest that the PAG harbors a hypoxia-sensitive alarm system the activation of which could both precipitate panic and render the subject hypersensitive to CO 2 . Although prior c-Fos immunohistochemistry studies reported widespread activations of PAG following KCN injections, the employment of repeated injections of high doses of KCN (>60µg) in anesthetized rats compromised both the localization of KCN-responsive areas and their correlation with escape behavior. Accordingly, here we compared the brainstem activations of saline-injected controls (air/saline) with those produced by a single intravenous injection of 40-µg KCN (air/KCN), a 2-min exposure to 13% CO 2 (CO 2 /saline), or a combined stimulus (CO 2 /KCN). Behavioral effects of KCN microinjections into the PAG were assessed as well. Data showed that whereas the KCN microinjections were ineffective, KCN intravenous injections elicited escape in all tested rats. Moreover, whereas the CO 2 alone was ineffective, it potentiated the KCN-evoked escape. Compared to controls, the nucleus tractus solitarius was significantly activated in both CO 2 /saline and CO 2 /KCN groups. Additionally, whereas the laterodorsal tegmental nucleus was activated by all treatments, the rostrolateral and caudoventrolateral PAG were activated by air/KCN only. Data suggest that the latter structures are key components of a hypoxia-sensitive suffocation alarm which activation may trigger a panic attack. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  11. Road design standards of medians, shoulders and verges. Annex VII to SWOV-report `Safety effects of road design standards', R-94-7 (see C 2838 (IRRD 866221).

    NARCIS (Netherlands)

    Schoon, C.C.

    1995-01-01

    This volume is one of the annexes to a main report on safety effects of road design standards which was compiled by SWOV in collaboration with other European partners, in 1993-1994. For the covering abstract of the report or the report itself, see C 2838. This annex compares the road design

  12. Från elitidrott till yrkeskarriär : En studie av elitidrottsutövares upplevelser av karriärövergång och ledarkvalitéer

    OpenAIRE

    Hellgren, Alfred; Hörnberg, Henrik

    2017-01-01

    There have been numerous of examples where former elite athletes have had a problem with adaptingto the life as a civilian. Research has shown that it is common among former athletes to experiencenegative emotions when ending an elite career in sports. What separated the ones who successfullymoved on to achieve greatness outside of the sports environment? This study was about female formerelite athletes which have a senior position and their views on what role the elite career had on theirfol...

  13. La memoria de la vergüenza o los restos del imperio: la representación literaria del conflicto en el Sáhara Occidental en la novela contemporánea

    Directory of Open Access Journals (Sweden)

    Ana Luengo

    2014-06-01

    Despite being in the spotlight in society and the media, the issue of decolonization of Western Sahara has barely been addressed in the discussion of historical memory in the contemporary Spanish novel. This article discusses two novels (El imperio desierto [1992], by Ramón Mayrata, and Mira si yo te querré [2007], by Luis Leante that deal with that episode in history and try to fill in a void in the actual literary field.

  14. Sensitivity of Malignant Rhabdoid Tumor cell lines to PD 0332991 is inversely correlated with p16 expression

    Science.gov (United States)

    Katsumi, Yoshiki; Iehara, Tomoko; Miyachi, Mitsuru; Yagyu, Shigeki; Tsubai-Shimizu, Satoko; Kikuchi, Ken; Tamura, Shinichi; Kuwahara, Yasumichi; Tsuchiya, Kunihiko; Kuroda, Hiroshi; Sugimoto, Tohru; Houghton, Peter J.; Hosoi, Hajime

    2011-01-01

    Malignant rhabdoid tumor (MRT) is a rare and highly aggressive neoplasm of young children. MRT is characterized by inactivation of integrase interactor 1 (INI1). Cyclin-dependent kinase 4 (CDK4), which acts downstream of INI1, is required for the proliferation of MRT cells. Here we investigated the effects of PD 0332991 (PD), a potent inhibitor of CDK4, against five human MRT cell lines (MP-MRT-AN, KP-MRT-RY, G401, KP-MRT-NS, KP-MRT-YM). In all of the cell lines except KP-MRT-YM, PD inhibited cell proliferation > 50 %, (IC50 values 0.01 to 0.6 µM) by WST-8 assay, and induced G1-phase cell cycle arrest, as shown by flow cytometry and BrdU incorporation assay. The sensitivity of the MRT cell lines to PD was inversely correlated with p16 expression (r = 0.951). KP-MRT-YM cells overexpress p16 and were resistant to the growth inhibitory effect of PD. Small interfering RNA against p16 significantly increased the sensitivity of KP-MRT-YM cells to PD (p MRT could be used to predict its sensitivity to PD. PD may be an attractive agent for patients with MRT whose tumors express low levels of p16. PMID:21871868

  15. On the low vibration modes observed in a sphere submitted to a tangential contact force.

    Science.gov (United States)

    De Billy, M

    2006-12-01

    In this paper we discuss the existence of translational and rotational displacements of a sphere submitted to a tangential contact force. On the basis of the Bogdanov and Skvortsov's works [A.N. Bogdanov, A.T. Skvortsov, Sov. Phys. Acoust. 38 (1992) 224-226.] the dispersion equation has been established and solved for any value of the frequency in the case of the linear approximation. The present experimental analysis confirms that it exists two branches: an upper branch associated to the translation of the sphere and a lower branch characteristic of the rotation of the bead.

  16. Sensitivity of malignant rhabdoid tumor cell lines to PD 0332991 is inversely correlated with p16 expression

    Energy Technology Data Exchange (ETDEWEB)

    Katsumi, Yoshiki; Iehara, Tomoko; Miyachi, Mitsuru; Yagyu, Shigeki; Tsubai-Shimizu, Satoko; Kikuchi, Ken; Tamura, Shinichi; Kuwahara, Yasumichi; Tsuchiya, Kunihiko; Kuroda, Hiroshi; Sugimoto, Tohru [Department of Pediatrics, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto 602-8566 (Japan); Houghton, Peter J. [Molecular Pharmacology, St. Jude Children' s Research Hospital, 332 N. Lauderdale St. Memphis, TN 38105-2794 (United States); Hosoi, Hajime, E-mail: hhosoi@koto.kpu-m.ac.jp [Department of Pediatrics, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto 602-8566 (Japan)

    2011-09-16

    Highlights: {yields} PD 0332991 (PD) could suppress four of five malignant rhabdoid tumor (MRT) cell lines. {yields} The sensitivity of the MRT cell lines to PD was inversely correlated with p16 expression (r = 0.951). {yields} p16 expression in MRT could be used to predict its sensitivity to PD. {yields} PD may be an attractive agent for patients with MRT whose tumors express low levels of p16. -- Abstract: Malignant rhabdoid tumor (MRT) is a rare and highly aggressive neoplasm of young children. MRT is characterized by inactivation of integrase interactor 1 (INI1). Cyclin-dependent kinase 4 (CDK4), which acts downstream of INI1, is required for the proliferation of MRT cells. Here we investigated the effects of PD 0332991 (PD), a potent inhibitor of CDK4, against five human MRT cell lines (MP-MRT-AN, KP-MRT-RY, G401, KP-MRT-NS, KP-MRT-YM). In all of the cell lines except KP-MRT-YM, PD inhibited cell proliferation >50%, (IC{sub 50} values 0.01 to 0.6 {mu}M) by WST-8 assay, and induced G1-phase cell cycle arrest, as shown by flow cytometry and BrdU incorporation assay. The sensitivity of the MRT cell lines to PD was inversely correlated with p16 expression (r = 0.951). KP-MRT-YM cells overexpress p16 and were resistant to the growth inhibitory effect of PD. Small interfering RNA against p16 significantly increased the sensitivity of KP-MRT-YM cells to PD (p < 0.05). These results suggest that p16 expression in MRT could be used to predict its sensitivity to PD. PD may be an attractive agent for patients with MRT whose tumors express low levels of p16.

  17. Mieren in Veluwebermen: soortenrijkdom en aanbevelingen voor beheer (Hymenoptera: Formicidae).

    NARCIS (Netherlands)

    Noordijk, J.; Boer, P.

    2007-01-01

    Ants in roadside verges on the Veluwe: species richness and recommendations for management (Hymenoptera: Formicidae) Highway verges in the Veluwe region contain some well developed nutrient poor plant communities, like grasslands, grey hair grass vegetation and heather vegetation. These places

  18. 75 FR 23749 - Combined Notice of Filings

    Science.gov (United States)

    2010-05-04

    ...-Mississippi River Transmission Corporation submits an amended negotiated rate agreement between MRT and LER... amended negotiated rate agreement between MRT and CES. Filed Date: 04/26/2010. Accession Number: 20100426...

  19. A tale of two viruses

    African Journals Online (AJOL)

    was 23 mmol/L. A chest radiograph revealed diffuse bilateral nodular interstitial infiltrates. Fig. 3 depicts typical varicella pneumonia. The diagnosis was that of disseminated varicella in a woman newly diagnosed with ... Bogdanovic M. Reactivation of herpes-zoster virus infection by varicella-zoster virus. Medicinski Pregled ...

  20. USSR Report: Cybernetics, Computers and Automation Technology. No. 69.

    Science.gov (United States)

    1983-05-06

    No 6, Nov-Dec 82 (manuscript received 20 Aug 82) pp 43-47 [Article by Candidate of Technical Sciences Leonid Ivanovich Sholmov, engineer Vasiliy... Gladshteyn , V. M. Komarov. Creating Finite Automatons with Selector-Multiplexers 31 M. A. Bogdanov. The KOK Language for Programming in the KAMAK

  1. The Changing Role of Naval Forces: The Russian View of the Persian Gulf War

    Science.gov (United States)

    1992-06-01

    Roman Zadunaisky report of intprnational conference "Armed Forces and Military Service in a Law-Governed State" and commen- tary by Sergey Bogdanov...Greenwich London SE109NN UNITED KINGDOM (via air mail) Dr. Henry Trofimenko Campus Box 2350 Elon College, North Carolina 27244 Dr. Harlan K. Ullman

  2. The Soviet Shift in Emphasis from Nuclear to Conventional. Volume 2. The Mid-Term Perspective

    Science.gov (United States)

    1983-06-01

    the Nuclear Maniacs ," Krasnaya zvezda, 13 August 1980. 136Yu.G. Strel’tsov and V.A. Mazing, "Nuclear War in a Theater of War," in Bogdanov...REPORT DOCUMENTATION PAGE READ INSTRUCTIONS BEFORE COMPLETING FORM 1. REPORT NUMBER CRC 490 - Volume II 2. GOVT ACCESSION NO 3- RECIPIENT’S

  3. 78 FR 21618 - Mortgagee Review Board: Administrative Actions

    Science.gov (United States)

    2013-04-11

    ... manner. 1. Banking Mortgage Services BMS Corp., Miami, FL ($3,500) [Docket No. 11-1249-MRT] 2. BM Real..., Farmington Hills, MI ($3,500) [Docket No. 11-1218-MRT] 4. Home Retention Services, Inc., Houston, TX ($7,500) [Docket No. 11- 1283-MRT] 5. Mortgage Corp of the East III, Rockland, MA ($3,500) [Docket No. 12- 1656-MRT...

  4. 77 FR 55492 - Mortgagee Review Board: Administrative Actions

    Science.gov (United States)

    2012-09-10

    ..., GA ($7,500.00) [Docket No. 11-1225-MRT] 2. Freyre Mortgage Corp., San Juan, PR. ($3,500.00) [Docket No. 11- 1229-MRT] III. Lenders That Failed To Meet Requirements for Annual Recertification of HUD/FHA... Mortgage, Inc., Jonesboro, AR [Docket No. 12-1642- MRT]. 2. HCL Finance Inc., San Jose, CA . 3. Ikon...

  5. Effects of Sleep Deprivation on U.S. Navy Watchstander Performance Onboard the Independence Class Littoral Combat Ship (LCS 2)

    Science.gov (United States)

    2013-09-01

    28 Figure 6. Switching Test MRT by day...speed (1/ MRT ) as a function of day .........................................30 Table 13. Daily minutes above or below NSWW sleep recommendation...preferred predictor for analysis of PVT performance. The reciprocal MRT is used because it minimizes the least squares error in the regression model

  6. 76 FR 1144 - CenterPoint Energy-Mississippi River Transmission Corporation; Notice of Application

    Science.gov (United States)

    2011-01-07

    ... Transmission Corporation (MRT), 1111 Louisiana Street, Houston, Texas 77002-5231, filed in Docket No. CP11-51... Unionville Storage Fields located in Lincoln Parish, Louisiana. MRT states that the Inventory Verification Study disclosed a difference of approximately 1.2 Bcf less cushion gas than the accounting records. MRT...

  7. Multivariable analysis of clinical influence factors on liver enhancement of Gd-EOB-DTPA-enhanced 3T MRI; Multivariable Analyse klinischer Einflussfaktoren auf die Signalintensitaet bei Gd-EOB-DTPA 3T-MRT der Leber

    Energy Technology Data Exchange (ETDEWEB)

    Verloh, N.; Haimerl, M.; Stroszczynski, C.; Fellner, C.; Wiggermann, P. [University Hospital Regensburg (Germany). Dept. of Radiology; Zeman, F. [University Hospital Regensburg (Germany). Center for Clinical Trials; Teufel, A. [University Hospital Regensburg (Germany). Dept. of Gastroenterology; Lang, S. [University Hospital Regensburg (Germany). Dept. of Surgery

    2015-01-15

    The purpose of this study was to identify clinical factors influencing Gd-EOB-DTPA liver uptake in patients with healthy liver parenchyma. A total of 124 patients underwent contrast-enhanced MRI with a hepatocyte-specific contrast agent at 3T. T1-weighted volume interpolated breath-hold examination (VIBE) sequences with fat suppression were acquired before and 20 minutes after contrast injection. The relative enhancement (RE) between plain and contrast-enhanced signal intensity was calculated. Simple and multiple linear regression analyses were performed to evaluate clinical factors influencing the relative enhancement. Patients were subdivided into three groups according to their relative liver enhancement (HRE, RE ≥ 100 %; MRE, 100 % > RE > 50 %; NRE, RE ≤ 50 %) and were analyzed according to the relevant risk factors. Simple regression analyses revealed patient age, transaminases (AST, ALT, GGT), liver, spleen and delta-liver volume (the difference between the volumetrically measured liver volume and the estimated liver volume based on body weight) as significant factors influencing relative enhancement. In the multiple analysis the transaminase AST, spleen and delta liver volume remained significant factors influencing relative enhancement. Delta liver volume showed a significant difference between all analyzed groups. Liver enhancement in the hepatobiliary phase depends on a variety of factors. Body weight-adapted administration of Gd-EOB-DTPA may lead to inadequate liver enhancement after 20 minutes especially when the actual liver volume differs from the expected volume.

  8. 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.

  9. 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...

  10. 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.

  11. 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.)

  12. 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.

  13. 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.)

  14. 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.)

  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. 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.

  17. Current stage of fMRI applications in newborns and children during the first year of life; Gegenwaertiger Stand der funktionellen MRT bei Neugeborenen und Kindern im ersten Lebensjahr

    Energy Technology Data Exchange (ETDEWEB)

    Boecker, H.; Scheef, L.; Jankowski, J.; Zimmermann, N. [Radiologische Universitaetsklinik Bonn, FE Klinische Funktionelle Neurobildgebung (Germany); Born, M. [Radiologische Universitaetsklinik Bonn, FE Kinderradiologie (Germany); Heep, A. [Zentrum fuer Kinderheilkunde der Univ. Bonn, Abt. fuer Neonatologie (Germany)

    2008-08-15

    Currently, a paradigm shift towards expanded early use of cranial MRI in newborns at risk and infants in the first year of life can be observed in neonatology. Beyond clinical MRI applications, there is progressive use of functional MRI (fMRI) in this age group. On the one hand, fMRI allows monitoring of functional developmental processes depending on maturational stage; on the other hand, this technique may provide the basis for early detection of pathophysiological processes as a prerequisite for functionally guided therapeutic interventions. This article provides a comprehensive review of current fMRI applications in neonates and infants during the first year of life and focuses on the associated methodological issues (e.g. signal physiology, sedation, safety aspects). (orig.)

  18. 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).

  19. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  20. Influence on flux density of intraoral dental magnets during 1.5 and 3.0 Tesla MRI; Beeinflussung der Flussdichte intraoraler Dentalmagnete im 1,5 und 3 Tesla-MRT

    Energy Technology Data Exchange (ETDEWEB)

    Blankenstein, F.H.; Peroz, I. [Charite, Berlin (Germany). Charite Centrum 3 - Zahn-, Mund- und Kieferheilkunde; Truong, B. [Zahnarztpraxis Berlin (Germany); Thomas, A. [Charite, Berlin (Germany). Charite Centrum 6 - Diagnostische und Interventionelle Radiologie und Nuklearmedizin; Boeckler, A. [Halle-Wittenberg Univ. (Germany). Zentrum fuer Zahn-, Mund- und Kieferheilkunde

    2011-08-15

    Purpose: When using dental duo-magnet systems, a mini-magnet remains in the jaw after removal of the prosthesis. In some cases, implant-borne magnets may be removed, whereas tooth-borne magnets are irreversibly fixed on a natural tooth root. The goal of this paper is to identify the impacts of the duration and orientation of exposure on these magnets in a 1.5 or 3 Tesla MRI. Materials and Methods: For this study, 30 SmCo and 60 NdFeB magnets were used. During the first experiment, they were exposed with free orientation for 64 minutes. During the second experiment, the magnets were fixed in position and exposed at 1.5 and 3 Tesla while aligned in a parallel or antiparallel direction. Results: While the duration of exposure in MRI is irrelevant, the orientation is not. The coercive field strength of these NdFeB and SmCo alloys is not sufficient to reliably withstand demagnetization in a 1.5 or 3 T MRI when aligned in an antiparallel direction. At 1.5 T neodymium magnets were reduced to approx. 34 % and samarium magnets to approx. 92 % of their initial values. At 3 T all magnets were reversed. Conclusion: As a precaution, the worst-case scenario, i.e. an antiparallel orientation, should be assumed when using a duo-magnet system. If an MRI can be postponed, the general dentist should remove implant-borne magnets. If there is a vital indication, irreversible damage to the magnets is acceptable in consultation with the patient since the replacement costs are irrelevant given the underlying disease. (orig.)

  1. 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.)

  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

    Energy Technology Data Exchange (ETDEWEB)

    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. Comparison of T{sub 2}-weighted turbo-spin echo sequence and ultra-fast HASTE sequence in the diagnosis of cervical myelopathies and spinal stenoses against static and kinematic MRT of the cervical spine; Vergleich von T{sub 2}-gewichteter Turbo-Spin-Echo- und ultraschneller, HASTE-Sequenz in der Diagnostik von zervikalen Myelopathien und Spinalstenosen mit der statischen und kinematischen MRT der Halswirbelsaeule

    Energy Technology Data Exchange (ETDEWEB)

    Muhle, C.; Metzner, J.; Brinkmann, G.; Kuehn, B.; Bischoff, L.; Hutzelmann, A.; Wesner, F.; Heller, M. [Klinik fuer Radiologische Diagnostik, Christian-Albrechts-Universitaet zu Kiel (Germany)

    1997-11-01

    Purpose: The purpose of this study was to compare HASTE-sequence with T{sub 2}-weighted TSE-sequence in the detection of cervical myelopathy and cervical spinal stenosis in kinematic MRI. Methods: 24 patients with degenerative disease of the cervical spine were studied. Images were evaluated according to the following criteria: Artifacts, delineation of the vertebra, disks and degenerative changes, grade of spinal stenosis (grade 0-3) and evaluation of the cervical spinal cord. Results: Due to image blurring and artifacts, evaluation and delineation of the cervical spine was possible in all cases in the T{sub 2}-weighted TSE-sequence, but only in 23 of 24 patients using HASTE-sequence. Differentiation between osteophytes and disks was obtained in most cases (23/24) in the T{sub 2}-weighted TSE-sequence but none in the HASTE-sequence. Cervical myelopathy was observed in 4 patients in T{sub 2}-weighted TSE images but only in two cases using HASTE-sequence. Compared to T{sub 2}-weighted TSE-sequence spinal canal stenosis was underestimated using HASTE-sequence. (orig./AJ) [Deutsch] Ziel: Beurteilung von zervikalen Myelopathien und Spinalstenosen im Vergleich von ultraschneller HASTE-Sequenz sowie T{sub 2}-TSE-Sequenz. Methode: 24 Patienten mit degenerativen Halswirbelsaeulenveraenderungen wurden untersucht. Die Aufnahmen wurden hinsichtlich der Artefaktanfaelligkeit, der Darstellung von Halswirbelkoerper, Bandscheiben und degenerativen Veraenderungen, dem Grad einer Spinalstenose (Stadium 0-3) sowie der Beurteilung des Zervikalmarks ausgewertet. Ergebnisse; Aufgrund von ausgepraegten Artefakten konnten nur 23 von 24 Untersuchungen mit der HASTE-Sequenz, hingegen alle Untersuchungen mit der T{sub 2}-TSE-Sequenz ausgewertet werden. Eine Differenzierung von osteophytaeren Randanbauten von Bandscheiben und Wirbelkoerpern war in der HASTE-Sequenz gegenueber der T{sub 2}-TSE-Sequenz nur eingeschraenkt moeglich. Eine in 4 Faellen in der T{sub 2}-TSE-Sequenz diagnostizierte zervikale Myelopathie wurde bei 2 Patienten in der HASTE-Sequenz erkannt. In der Bewertung der Spinalkanalstenose zeigte die HASTE-Sequenz ein geringeres Stenosestadium. (orig./AJ)

  4. Homozygosity mapping in 64 Syrian consanguineous families with non-specific intellectual disability reveals 11 novel loci and high heterogeneity.

    Science.gov (United States)

    Abou Jamra, R; Wohlfart, Sigrun; Zweier, Markus; Uebe, Steffen; Priebe, Lutz; Ekici, Arif; Giesebrecht, Susanne; Abboud, Ahmad; Al Khateeb, Mohammed Ayman; Fakher, Mahmoud; Hamdan, Saber; Ismael, Amina; Muhammad, Safia; Nöthen, Markus M; Schumacher, Johannes; Reis, André

    2011-11-01

    Non-specific intellectual disability of autosomal recessive inheritance (NS-ARID) represents an important fraction of severe cognitive dysfunction disorders. To date, only 10 genes have been identified, and further 24 linked-ARID loci have been reported, as well as others with suggestive linkage. To discover novel genes causing NS-ARID, we undertook genome-wide homozygosity mapping in 64 consanguineous multiplex families of Syrian descent. A total of 11 families revealed unique, significantly linked loci at 4q26-4q28 (MRT17), 6q12-q15 (MRT18), 18p11 (MRT19), 16p12-q12 (MRT20), 11p15 (MRT21), 11p13-q14 (MRT23), 6p12 (MRT24), 12q13-q15 (MRT25), 14q11-q12 (MRT26), 15q23-q26 (MRT27), and 6q26-q27 (MRT28), respectively. Loci ranged between 1.2 and 45.6 Mb in length. One family showed linkage to chromosome 8q24.3, and we identified a mutation in TRAPPC9. Our study further highlights the extreme heterogeneity of NS-ARID, and suggests that no major disease gene is to be expected, at least in this study group. Systematic analysis of large numbers of affected families, as presented here, will help discovering the genetic causes of ID.

  5. Identification of AREG and PLK1 pathway modulation as a potential key of the response of intracranial 9L tumor to microbeam radiation therapy.

    Science.gov (United States)

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

    2015-06-01

    Synchrotron microbeam radiation therapy (MRT) relies on the spatial fractionation of a synchrotron beam into parallel micron-wide beams allowing deposition of hectogray doses. MRT controls the intracranial tumor growth in rodent models while sparing normal brain tissues. Our aim was to identify the early biological processes underlying the differential effect of MRT on tumor and normal brain tissues. The expression of 28,000 transcripts was tested by microarray 6 hr after unidirectional MRT (400 Gy, 50 µm-wide microbeams, 200 µm spacing). The specific response of tumor tissues to MRT consisted in the significant transcriptomic modulation of 431 probesets (316 genes). Among them, 30 were not detected in normal brain tissues, neither before nor after MRT. Areg, Trib3 and Nppb were down-regulated, whereas all others were up-regulated. Twenty-two had similar expression profiles during the 2 weeks observed after MRT, including Ccnb1, Cdc20, Pttg1 and Plk1 related to the mitotic role of the Polo-like kinase (Plk) pathway. The up-regulation of Areg expression may indicate the emergence of survival processes in tumor cells triggered by the irradiation; while the modulation of the "mitotic role of Plk1" pathway, which relates to cytokinetic features of the tumor observed histologically after MRT, may partially explain the control of tumor growth by MRT. The identification of these tumor-specific responses permit to consider new strategies that might potentiate the antitumoral effect of MRT. © 2014 UICC.

  6. LA FRACTURE DU CORPS CAVERNEUX. A PROPOS DE 123 CAS

    African Journals Online (AJOL)

    LA FRACTURE DU CORPS CAVERNEUX. Tableau 1: Mécanisme de la Rupture Traumatique du Corps Caverneux. Mécanisme. Nombre de Cas Fréquence (%). Manipulation forcée de la verge en érection. Retournement sur vergé en érection pendant le sommeil. Faux pas du coi't. Choc sur verge en érection. Non précisé.

  7. Codimension-2 bifurcations of the Kaldor model of business cycle

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Xiaoqin P., E-mail: xpaul_wu@yahoo.co [Department of Mathematics, Computer and Information Sciences, Mississippi Valley State University, Itta Bena, MS 38941 (United States)

    2011-01-15

    Research highlights: The conditions are given such that the characteristic equation may have purely imaginary roots and double zero roots. Purely imaginary roots lead us to study Hopf and Bautin bifurcations and to calculate the first and second Lyapunov coefficients. Double zero roots lead us to study Bogdanov-Takens (BT) bifurcation. Bifurcation diagrams for Bautin and BT bifurcations are obtained by using the normal form theory. - Abstract: In this paper, complete analysis is presented to study codimension-2 bifurcations for the nonlinear Kaldor model of business cycle. Sufficient conditions are given for the model to demonstrate Bautin and Bogdanov-Takens (BT) bifurcations. By computing the first and second Lyapunov coefficients and performing nonlinear transformation, the normal forms are derived to obtain the bifurcation diagrams such as Hopf, homoclinic and double limit cycle bifurcations. Some examples are given to confirm the theoretical results.

  8. Two Improved Multiple-Differential Collision Attacks

    Directory of Open Access Journals (Sweden)

    An Wang

    2014-01-01

    Full Text Available In CHES 2008, Bogdanov proposed multiple-differential collision attacks which could be applied to the power analysis attacks on practical cryptographic systems. However, due to the effect of countermeasures on FPGA, there are some difficulties during the collision detection, such as local high noise and the lack of sampling points. In this paper, keypoints voting test is proposed for solving these problems, which can increase the success ratio from 35% to 95% on the example of one implementation. Furthermore, we improve the ternary voting test of Bogdanov, which can improve the experiment efficiency markedly. Our experiments show that the number of power traces required in our attack is only a quarter of the requirement of traditional attack. Finally, some alternative countermeasures against our attacks are discussed.

  9. A Viral Infection Model with a Nonlinear Infection Rate

    Directory of Open Access Journals (Sweden)

    Nieto JuanJ

    2009-01-01

    Full Text Available A viral infection model with a nonlinear infection rate is constructed based on empirical evidences. Qualitative analysis shows that there is a degenerate singular infection equilibrium. Furthermore, bifurcation of cusp-type with codimension two (i.e., Bogdanov-Takens bifurcation is confirmed under appropriate conditions. As a result, the rich dynamical behaviors indicate that the model can display an Allee effect and fluctuation effect, which are important for making strategies for controlling the invasion of virus.

  10. Analysis of a quadratic system obtained from a scalar third order differential equation

    Directory of Open Access Journals (Sweden)

    Fabio Scalco Dias

    2010-11-01

    Full Text Available In this article, we study the nonlinear dynamics of a quadratic system in the three dimensional space which can be obtained from a scalar third order differential equation. More precisely, we study the stability and bifurcations which occur in a parameter dependent quadratic system in the three dimensional space. We present an analytical study of codimension one, two and three Hopf bifurcations, generic Bogdanov-Takens and fold-Hopf bifurcations.

  11. Nonlinear Interaction of Transversal Modes in a CO2 Laser

    OpenAIRE

    Lopez-Ruiz, Ricardo; Mindlin, G. B.; Perez-Garcia, C.; Tredicce, J. R.

    2002-01-01

    We show the possibility of achieving experimentally a Takens-Bogdanov bifurcation for the nonlinear interaction of two transverse modes ($l = \\pm 1$) in a $CO_2$ laser. The system has a basic O(2) symmetry which is perturbed by some symmetry-breaking effects that still preserve the $Z_2$ symmetry. The pattern dynamics near this codimension two bifurcation under such symmetries is described. This dynamics changes drastically when the laser properties are modified.

  12. ATTITUDES OF SPORTS FANS IN MONTENEGRO TOWARD NATIONAL IDENTITY AMONG THE FREQUENCY OF THEIR PARTICIPATION IN SPORT ACTIVITIES

    OpenAIRE

    Stevo Popović; Duško Bjelica; Ivan Vasiljević; Rašid Hadžić

    2014-01-01

    Introduction: Sport and national identity have been strongly connected through entire history, mostly due to the reason that an individual sportsmen or a national sport team may represent a certain group of people united around a single goal or the same ideas (Popović & Bjelica, 2013). Hence, they, accompanied with the sports fans, represent an entire nation and foster a sense of national pride amongst members of a given nation (Bogdanov, 2011). Consequently, this research was aimed at gainin...

  13. Principles and Application of Magnetic Rubber Testing for Crack Detection in High-Strength Steel Components: II. Residual-Field Inspection

    Science.gov (United States)

    2014-12-01

    ABSTRACT Since its introduction in the 1970s, magnetic rubber testing ( MRT ) has been used successfully to inspect critical high-strength steel...aerospace components for surface-breaking fatigue cracks. In the residual-field variant of MRT , inspections are performed following the application...geometries, residual-field MRT is capable of reliable detection of cracks as small as 0.43 mm (0.017 inch) in surface length. However, for other conditions

  14. Follow up on the Actions to Improve the Defense Contract Management Agencys Cost Analysis Function

    Science.gov (United States)

    2015-10-29

    is completed, DCMA Office of Independent Assessment (DCMA Internal Review), Mission Review Team ( MRT ) will revise current Mission Review (MR...Dir ctor. December 20, 2011 July 30, 2012 Revise MRT Pricing Assessment Guide and Workbook – Add emphasis on review of eTools data January 5, 2012...August 15, 2012 Complete MRT review and approval process January 10, 2012 August 30, 2012 Conduct MRs to evaluate P&N eTools and policy changes

  15. Principles and Application of Magnetic Rubber Testing for Crack Detection in High-Strength Steel Components: I. Active-Field Inspection

    Science.gov (United States)

    2014-12-01

    ABSTRACT Magnetic rubber testing ( MRT ) is a sensitive non-destructive inspection technique, capable of detecting cracks as small as 0.5 mm (0.020...inch) in length with high reliability. Since its introduction in the 1970s, MRT has been successfully used to inspect high-strength steel aerospace...components for surface-breaking fatigue cracks. However, despite its widespread use and apparent simplicity, the underpinning science of MRT is not

  16. Entwicklung einer im Magnetresonanztomografen einsatzfähigen chirurgischen Bohrmaschine

    OpenAIRE

    Winterwerber, Kim

    2011-01-01

    Jüngste Entwicklungen in der Magnetresonanztomografie (MRT) ermöglichen die Darstellung von Schnittbildern des menschlichen Körpers in Echtzeit, so dass sich erstmals Operationen im MRT durchführen lassen. Ziel ist es daher, die Instrumente im MRT-Bild maßstabsgetreu darzustellen, da erst dann der Einsatz MRT-kontrollierter und navigierter Eingriffe gelingen kann. Herkömmliche chirurgische Instrumente und Geräte aus Edelstahl erzeugen aufgrund ihrer hohen magnetischen Suszeptibilitäten Abbild...

  17. 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.

  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. The Divisive Threat of Immigration in Europe

    Science.gov (United States)

    2012-12-01

    17 42 http://www.thefreedictionary.com/extreme+right-winger, 08/05/2012 43 “ Rechtspopulismus in Europa. Vergängliches Phänomen oder auf dem Weg zum...when?” Electoral Sociology, www.kai-arzheimer.com/arzheimer-rwe.pdf (accessed May 2012). Bauer, T. W. “ Rechtspopulismus in Europa. Vergängliches

  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. Sparing of tissue by using micro-slit-beam radiation therapy reduces neurotoxicity compared with broad-beam radiation therapy.

    Science.gov (United States)

    Mukumoto, Naritoshi; Nakayama, Masao; Akasaka, Hiroaki; Shimizu, Yasuyuki; Osuga, Saki; Miyawaki, Daisuke; Yoshida, Kenji; Ejima, Yasuo; Miura, Yasushi; Umetani, Keiji; Kondoh, Takeshi; Sasaki, Ryohei

    2017-01-01

    Micro-slit-beam radiation therapy (MRT) using synchrotron-generated X-ray beams allows for extremely high-dose irradiation. However, the toxicity of MRT in central nervous system (CNS) use is still unknown. To gather baseline toxicological data, we evaluated mortality in normal mice following CNS-targeted MRT. Male C57BL/6 J mice were head-fixed in a stereotaxic frame. Synchrotron X-ray-beam radiation was provided by the SPring-8 BL28B2 beam-line. For MRT, radiation was delivered to groups of mice in a 10 × 12 mm unidirectional array consisting of 25-μm-wide beams spaced 100, 200 or 300 μm apart; another group of mice received the equivalent broad-beam radiation therapy (BRT) for comparison. Peak and valley dose rates of the MRT were 120 and 0.7 Gy/s, respectively. Delivered doses were 96-960 Gy for MRT, and 24-120 Gy for BRT. Mortality was monitored for 90 days post-irradiation. Brain tissue was stained using hematoxylin and eosin to evaluate neural structure. Demyelination was evaluated by Klüver-Barrera staining. The LD50 and LD100 when using MRT were 600 Gy and 720 Gy, respectively, and when using BRT they were 80 Gy and 96 Gy, respectively. In MRT, mortality decreased as the center-to-center beam spacing increased from 100 μm to 300 μm. Cortical architecture was well preserved in MRT, whereas BRT induced various degrees of cerebral hemorrhage and demyelination. MRT was able to deliver extremely high doses of radiation, while still minimizing neuronal death. The valley doses, influenced by beam spacing and irradiated dose, could represent important survival factors for MRT. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  2. 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

  3. A Mitochondrial Story: Mitochondrial Replacement, Identity and Narrative.

    Science.gov (United States)

    Scully, Jackie Leach

    2017-01-01

    Mitochondrial replacement techniques (MRT) are intended to avoid the transmission of mitochondrial diseases from mother to child. MRT represent a potentially powerful new biomedical technology with ethical, policy, economic and social implications. Among other ethical questions raised are concerns about the possible effects on the identity of children born from MRT, their families, and the providers or donors of mitochondria. It has been suggested that MRT can influence identity (i) directly, through altering the genetic makeup and physical characteristics of the child, or (ii) indirectly through changing the child's experience of disease, and by generating novel intrafamilial relationships that shape the sense of self. In this article I consider the plausibility and ethical implications of these proposed identity effects, but I focus instead on a third way in which identity may be affected, through the mediating influence of the wider social world on MRT effects on identity. By taking a narrative approach, and examining the nature and availability of identity narratives, I conclude that while neither direct genetic nor indirect experiential effects can be excluded, social responses to MRT are more likely to have a significant and potentially damaging influence on the generation of MRT children's narratives of identity. This conclusion carries some implications for the collective moral responsibility we hold to ensure that MRT, if implemented, are practised in ethically justifiable ways. © 2017 John Wiley & Sons Ltd.

  4. 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

  5. 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…

  6. Quality of MR thermometry during palliative MR-guided high-intensity focused ultrasound (MR-HIFU) treatment of bone metastases

    NARCIS (Netherlands)

    Lam, Mie K; Huisman, Merel; Nijenhuis, Robbert J; van den Bosch, Maurice; Viergever, Max A; Moonen, Chrit Tw; Bartels, LW

    2015-01-01

    BACKGROUND: Magnetic resonance (MR)-guided high-intensity focused ultrasound has emerged as a clinical option for palliative treatment of painful bone metastases, with MR thermometry (MRT) used for treatment monitoring. In this study, the general image quality of the MRT was assessed in terms of

  7. Passive Attenuating Communication Earphone (PACE): Noise Attenuation and Speech Intelligibility Performance When Worn in Conjunction with the HGU-56/P and HGU-55/P Flight Helmets

    Science.gov (United States)

    2013-10-16

    vented, MRT 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON Richard McKinley a...subjects from 5 talkers and 5 listeners to 5 talkers and 4 listeners. The Modified Rhyme Test ( MRT ) was selected for the test material. Each subject

  8. Treating Brain Tumor with Microbeam Radiation Generated by a Compact Carbon-Nanotube-Based Irradiator: Initial Radiation Efficacy Study.

    Science.gov (United States)

    Yuan, Hong; Zhang, Lei; Frank, Jonathan E; Inscoe, Christina R; Burk, Laurel M; Hadsell, Mike; Lee, Yueh Z; Lu, Jianping; Chang, Sha; Zhou, Otto

    2015-09-01

    Microbeam radiation treatment (MRT) using synchrotron radiation has shown great promise in the treatment of brain tumors, with a demonstrated ability to eradicate the tumor while sparing normal tissue in small animal models. With the goal of expediting the advancement of MRT research beyond the limited number of synchrotron facilities in the world, we recently developed a compact laboratory-scale microbeam irradiator using carbon nanotube (CNT) field emission-based X-ray source array technology. The focus of this study is to evaluate the effects of the microbeam radiation generated by this compact irradiator in terms of tumor control and normal tissue damage in a mouse brain tumor model. Mice with U87MG human glioblastoma were treated with sham irradiation, low-dose MRT, high-dose MRT or 10 Gy broad-beam radiation treatment (BRT). The microbeams were 280 μm wide and spaced at 900 μm center-to-center with peak dose at either 48 Gy (low-dose MRT) or 72 Gy (high-dose MRT). Survival studies showed that the mice treated with both MRT protocols had a significantly extended life span compared to the untreated control group (31.4 and 48.5% of life extension for low- and high-dose MRT, respectively) and had similar survival to the BRT group. Immunostaining on MRT mice demonstrated much higher DNA damage and apoptosis level in tumor tissue compared to the normal brain tissue. Apoptosis in normal tissue was significantly lower in the low-dose MRT group compared to that in the BRT group at 48 h postirradiation. Interestingly, there was a significantly higher level of cell proliferation in the MRT-treated normal tissue compared to that in the BRT-treated mice, indicating rapid normal tissue repairing process after MRT. Microbeam radiation exposure on normal brain tissue causes little apoptosis and no macrophage infiltration at 30 days after exposure. This study is the first biological assessment on MRT effects using the compact CNT-based irradiator. It provides an alternative

  9. 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.

  10. 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.

  11. 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

    2017-01-01

    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. Key points Resistance training promotes improvement in muscular strength and endurance MRT is an effective alternative form of resistance training for recreationally trained men. MRT can be effective to improve muscular strength and endurance in recreationally trained men. MRT should be considered as alternative form of resistance training by personal trainers and coaches. PMID:28912651

  12. 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.

  13. MRI based volumetric assessment of knee cartilage after ACL-reconstruction, correlated with qualitative morphologic changes in the joint and with clinical outcome. Is there evidence for early posttraumatic degeneration?; MRT-basierte Knorpelvolumetrie nach Kreuzbandersatzplastik in Korrelation mit qualitativen Gelenkveraenderungen und dem klinischen Outcome. Gibt es Hinweise auf fruehzeitige posttraumatische degenerative Veraenderungen?

    Energy Technology Data Exchange (ETDEWEB)

    Arnoldi, A.P.; Weckbach, S.; Horng, A.; Reiser, M. [Ludwig-Maximilians-Univ. Muenchen (Germany). Dept. of Clinical Radiology; Nussbickel, C. [Klinikum Garmisch-Partenkirchen (Germany). Dept. of Internal Medicine; Noebauer, I. [Medizinische Universitaet Wien (Austria). Klinik fuer Radiodiagnostik; Zysk, S. [Orthopaedie Zentrum Groebenzell (Germany). Center of Orthopaedics; Glaser, C. [NYU Medical Center, New York, NY (United States). Dept. of Radiology

    2011-12-15

    Purpose: The purpose of this study was to analyze potential quantitative and qualitative changes of the knee cartilage and joint indicative of early posttraumatic OA 4 years after ACL-reconstruction and to correlate the MRI-findings with the clinical outcome (CO). Materials and Methods: 1.5 T MRI-scans were performed on 9 patients post-op and 4 years later. Using a high-resolution T 1-w-fs-FLASH-3D-sequence cartilage volume (cVol) and thickness (mTh) were quantified. Using standard PD-w fs and T 1-w sequences qualitative changes of the joint structures were analyzed based on the WORMS-score. CO was rated by an orthopaedic surgeon using Lysholm-score, OAK-score, Tegner-activity-score (TAS), and Arthrometer KT-1000 testing. Results: Mean changes of cVol were -1.8 % (range: -5.9 %; + 0.7 %) and of mTh -0.8 % (range: -3.0 %; + 1.1 %). No significant change (95 %-CI) could be identified for any compartment. Three patients developed new peripatellar ostheophytes, acute trauma related changes mostly decreased. Mean outcome of Lysholm-score and OAK-score were 90 pts and 86 pts, mean TAS was 4.3 pts. Average maximum tibial translation reached 5.2 mm comparing to 6.7 mm on the healthy contralateral side. Conclusion: Despite a tendency towards decreased cVol and mTh 4 years after ACL-reconstruction qMRI revealed no significant cartilage loss. Newly developing osteophytes did not match with the observed good CO. This small pilot study motivates future quantitative and qualitative-structural MRI-based assessment of articular cartilage and other joint structures in order to improve diagnostic tools for the detection of early OA. (orig.)

  14. Dynamic MRI of the bone marrow for monitoring multiple myeloma during treatment with thalidomide as monotherapy or in combination with CED chemotherapy; Dynamische MRT des Knochenmarks zum Monitoring des Multiplen Myeloms unter Thalidomid-Monotherapie oder Kombination mit CED-Chemotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Wasser, K. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Abt. Onkologische Diagnostik und Therapie; Universitaetsklinikum Mannheim (Germany). Inst. fuer Klinische Radiologie; Moehler, T.; Neben, K.; Goldschmidt, H.; Hillengass, J. [Universitaetsklinikum Heidelberg (Germany). Medizinische Klinik und Poliklinik V; Nosas, S.; Heiss, J.; Kauczor, H.U.; Delorme, S. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Abt. Onkologische Diagnostik und Therapie; Dueber, C. [Universitaetsklinikum Mannheim (Germany). Inst. fuer Klinische Radiologie

    2004-09-01

    Purpose: To quantify changes of bone marrow microcirculation in multiple myeloma (MM) using contrast enhanced dynamic MRI (dMRI) during thalidomide as antiangiogenic monotherapy or in combination with chemotherapy (cyclophosphamide, etoposide, dexamethasone). Materials and Methods: The study includes 63 patients with refractory or relapsed MM, who underwent dMRI with high temporal resolution (T1w-turboFLASH) of the lumbar spine before and following treatment. The contrast uptake was quantified using a two compartment model with the output parameters amplitude and k{sub ep} (exchange rate constant). The evaluation considered the initial dMRI finding (pathological or non-pathological) and the clinical therapeutic response (response or no response). Results: During monotherapy with thalidomide (n=38), no significant changes of the dMRI parameters were found, even when considering the initial dMRI finding (positive n=22) and the therapeutic response (responder n=14). The combination with chemotherapy (n=25) had a significant reduction of k{sub ep} (p=0.01) in 18 patients with positive initial dMRI finding and therapeutic response. Reduction of the amplitude was seen in most cases, but in the end without any significance (p=0.09). (orig.)

  15. MR imaging of focal liver lesions: value of Gadolinium-enhanced dynamic imaging of the whole liver using an ultra-fast 3D-turbo-gradient-echo sequence; MRT fokaler Leberlaesionen: Stellenwert Gadolinium-verstaerkter dynamischer Untersuchungen des gesamten Organs mit einer schnellen 3D-Turbo-Gradienten-Echo-Sequenz

    Energy Technology Data Exchange (ETDEWEB)

    Pauleit, D.; Textor, J.; Conrad, R.; Flacke, S.; Born, M.; Bachmann, R.; Kreft, B.; Schild, H. [Bonn Univ. (Germany). Radiologische Klinik; Gieseke, J. [Philips Medizin Systeme (Germany)

    1999-04-01

    Purpose: To determine the value of a dynamic Gd-enhanced ultrafast T{sub 1}-weighted 3D-turbo-gradient-echo sequence (3D-TFE) in the detection and characterization of focal liver lesions. Results: On 3D-TFE images more lesions (107/124) were identified than on T{sub 1}-weighted SE (101/124) and T{sub 1}-weighted FFE images (106/124), but less compared to T{sub 2}-weighted TSE SPIR images (115/124). The 3D-TFE-sequence provided additional information in 65/107 (61%) detected lesions by delineating the dynamic enhancement pattern, most valuable in patients with HCCs in 90%. Conclusions: On dynamic 3D-TFE images more lesions could be depicted than on conventional T{sub 1}-weighted SE and T{sub 1}-weighted FFE images. Visualization of the dynamic enhancement pattern provided additional information for tumor characterization in 61% of the detected lesions on the 3D-TFE images. (orig./AJ) [Deutsch] Ziel: Bestimmung des Stellenwerts einer dynamischen Gd-DTPA-verstaerkten schnellen T{sub 1}-gewsichteten 3D-Turbo-Gradienten-Echo-Sequenz (3D-TFE) fuer die Detektion und Charakterisierung fokaler Leberlaesionen. Ergebnisse: Von den 124 Leberlaesionen wurden mit der 3D-FFE-Sequenz 107, mit der T{sub 1}-gewichteten SE 101 und mit der T{sub 1}-gewichteten FFE-Sequenz 106 nachgewiesen. In der T{sub 2}-gewichteten TSE-SPIR-Sequenz konnten 115 Laesionen detektiert werden. Bei 65/107 in der 3D-TFE-Seq