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Sample records for bei hirntumoren perfusion

  1. Magnetic resonance spectroscopy of brain tumors; MR-Spektroskopie bei Hirntumoren

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    Ditter, P.; Hattingen, E. [Universitaetsklinikum Bonn, FE Neuroradiologie, Radiologische Klinik, Bonn (Germany)

    2017-06-15

    Diagnose und Therapie. Einige wichtige Differenzialdiagnosen wie niedrig- vs. hochmaligne Tumore beduerfen allerdings zusaetzlicher MR-Methoden. Es soll der Stellenwert der MR-Spektroskopie (MRS) bei Hirntumoren kritisch diskutiert werden. Die {sup 1}H-MRS misst nicht invasiv Konzentrationen normaler und pathologischer Hirnmetabolite. Sie basiert auf dem Prinzip, dass chemische Protonenverbindungen bestimmter Hirnmetabolite das aeussere Magnetfeld fokal abschwaechen und die Protonenresonanzfrequenz nach typischen Mustern veraendern. Parameterkarten der MRS Imaging (MRSI) bilden zudem Tumorheterogenitaet und peritumorale Veraenderungen ab. Hierbei sind die Muster von N-Acetyl-Aspartat, ''total'' Cholin (tCho) oder Kreatin relativ robust. Die Erkennung anderer Metabolite wie Myoinositol, Glutamat, Laktat oder Lipide haengt hingegen stark von Faktoren wie Feldstaerke und Echozeit ab. Fuer solide Hirntumoren gilt, dass die tCho-Signalintensitaet in vitalem Tumorgewebe mit dem WHO-Grad des Hirntumors, d. h. mit der Malignitaet ansteigt. Die MRSI hilft, Gliome zu graduieren und den Zielpunkt bei Tumorbiopsien zu bestimmen. Unterschiedliche Verteilungsmuster bzw. spezielle Metabolitensignale erleichtern, zwischen Abszessen, Metastasen, ZNS-Lymphomen und Gliomen zu unterscheiden. Die {sup 1}H-MRSI liefert diagnostisch wertvolle Informationen zur Differenzialdiagnose und Graduierung von Hirntumoren, allerdings erschweren Artefakte, Signalstaerke, Parameterauswahl und fehlende Standardisierung - bislang - deren Einsatz in der Routinediagnostik. (orig.)

  2. Pediatric brain tumors; Kindliche Hirntumoren

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

    2017-09-15

    Brain tumors differ between children and adults both in histology and localization. Malignant gliomas and meningiomas predominate in adults while medulloblastomas and low-grade astrocytomas are the most frequent brain tumors in children. More than one half (50-70%) of pediatric brain tumors have an infratentorial location but only approximately 30% in adults. Brain tumors can be recognized in sonography, cranial computed tomography (CCT) and magnetic resonance imaging (MRI) by their space-consuming character and by their divergent density and intensity in comparison to normal brain parenchyma. They can grow extrusively, even infiltrate the parenchyma or originate from it. Besides clinical symptoms and diagnostics this article describes the most common pediatric brain tumors, i.e. astrocytoma, medulloblastoma, brainstem glioma, craniopharyngioma, neurofibromatosis and ganglioglioma. The most important imaging criteria are outlined. (orig.) [German] Sowohl Histologie als auch Lokalisation von Hirntumoren unterscheiden sich bei Kindern und Erwachsenen. Waehrend maligne Gliome und Meningeome bei Erwachsenen vorherrschen, kommen bei Kindern ueberwiegend Medulloblastome und niedriggradige Astrozytome vor. Mehr als die Haelfte (50-70 %) aller kindlichen Hirntumoren sind infratentoriell lokalisiert, dagegen sind es bei Erwachsenen nur etwa 30 %. Im Ultraschall, in der kranialen CT (CCT) oder MRT koennen Hirntumoren durch ihren raumfordernden Charakter und ihrer zum normalen Parenchym abweichenden Dichte oder Signalintensitaet erkannt werden. Sie koennen verdraengend wachsen, z. T. auch das Parenchym infiltrieren oder von diesem ausgehen. Neben der klinischen Symptomatik und Diagnostik werden im vorliegenden Artikel die haeufigsten kindlichen Hirntumoren, das Astrozytom, Medulloblastom, Hirnstammgliom, Kraniopharyngeom, die Neurofibromatose und das Gangliogliom beschrieben. Die wichtigsten bildgebende Kriterien werden dargestellt. (orig.)

  3. Brain tumors in childhood; Hirntumoren im Kindesalter

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    Sinzig, M.; Gasser, J.; Hausegger, K.A. [Landeskrankenhaus Klagenfurt, Kinderradiologie RZI, Klagenfurt (Austria); Jauk, B. [Landeskrankenhaus Klagenfurt, Abt. fuer Kinder- und Jugendheilkunde, Klagenfurt (Austria)

    2008-10-15

    Central nervous system (CNS) tumors are the most common solid neoplasms in childhood and the second most common malignancies after leukemia in the pediatric age group. Supratentorial tumors are more common in children younger than 2 years old and in adolescents, whereas in patients between 2 and 12 years of age brain tumors originating in the posterior fossa dominate. This implies a relationship between the type of tumor, its location and the age of the patient, which has to be considered in differential diagnoses. Medulloblastoma represents the most common malignant brain tumor in childhood. In the posterior fossa medulloblastomas are approximately as frequent as astrocytomas. Supratentorial astrocytomas are by far the main tumor type. In this report some typical CNS neoplasms in children are discussed and their neuroradiological features are demonstrated. (orig.) [German] Hirntumoren sind die haeufigsten soliden Tumoren des Kindesalters und repraesentieren nach den Leukaemien die zweithaeufigsten malignen Erkrankungen bei Kindern. Waehrend bei Kleinkindern und Adoleszenten supratentorielle Hirntumoren ueberwiegen, ist bei Patienten zwischen 2 und 12 Jahren haeufiger die hintere Schaedelgrube Ursprungsort dieser Malignome. Daraus geht hervor, dass gewisse Tumortypen eine gewisse Alterspraedilektion aufweisen, was neben der radiologischen Morphologie der Raumforderung fuer differenzialdiagnostische Ueberlegungen ueberaus hilfreich sein kann. Das Medulloblastom ist das haeufigste ZNS-Malignom des Kindesalters und repraesentiert zusammen mit zerebellaeren Astrozytomen auch den haeufigsten Tumortyp der hinteren Schaedelgrube. Supratentoriell stehen die Astrozytome ganz im Vordergrund. In dieser Arbeit werden einige typische kindliche infra- und supratentorielle Hirntumoren diskutiert und ihre neuroradiologischen Merkmale dargestellt. (orig.)

  4. Comparison of contract appearance of gadobenate-dimeglumine and GA-DTPA in intra-axial brain tumors; Vergleich des Kontrastverhaltens von Gadobenat-Dimeglumine und Gd-DTPA bei intraaxialen Hirntumoren. Eine doppelblinde randomisierte intraindividuelle Cross-over-Studie

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    Essig, M.; Knopp, M.V. [Deutsches Krebsforschungszentrum Heidelberg (Germany). Abt. Radiologische Diagnostik und Therapie; Hartmann, M.; Jansen, O. [Abt. Klinische Neuroradiologie, Univ. Heidelberg (Germany); Lodemann, K.P.; Seeberg, A. [Bracco-Byk-Gulden, Konstanz (Germany); Runge, V.M. [Univ. of Kentucky, Lexington (United States)

    2001-12-01

    The purposes of the study was to assess intraaxial brain tumors by a blinded comparison of gadobenat-dimeglumine and Gd-DTPA 27 patients with known cerebral gliomas or metastases were included into an intra-individual randomized double-blinded cross-over study. The protocol included T1 SE, T2 FSE and after contrast a series of five T1 SE sequences followed by T1 SE with MT, T1 SE, and 3D GRE sequences. Imaging data acquired at two centers were assessed on-site by the investigators and off-site by two experienced readers using quantitative and qualitative criteria. For a quantitative analysis tumor contrast and contrast-to-noise ratios were determined out of ROI in tumor, unaffected white matter, a region outside the head, and an external reference tube. For the qualitative assessment on- and off-site readers were asked to compare both MR scans for lesion contrast, lesion delineation and information upon the internal morphology and structure. In the quantitative analysis lesions examined with gadobenat-dimeglumine present a maximal 26% increase of the lesion contrast. In both, the on-site, as well as the off-site assessment the intensity of enhancement and the lesion contrast were found to be significantly better with gadobenat-dimeglumine enhanced MRI. There was a trend towards gadobenat-dimeglumine for the delineation of the lesion from the surrounding tissue and the internal lesion morphology. Based on our observations gadobenat-dimeglumine proved to be a safe and valuable contrast media for the assessment of CNS neoplasms. Compared with Gd-DTPA it provides a more intense contrast enhancement and a better tumor contrast which might be of importance for the further management of these patients. (orig.) [German] In einer doppelt verblindeten randomisierten intraindividuel en Cross-Over Vergleichsuntersuchung wurden 27 Patienten mit intraaxialen Hirntumoren mittels der MR-Kontrastmittel Gadobenat-Dimeglumine (Multihance trademark) und Gd-DTPA (Magnevist{sup circled

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

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

    2003-08-01

    Stimulationssysteme, standardisierte Untersuchungsprotokolle und fuer medizinische Anwendungen zugelassene Auswertungsprogramme fehlen. In dieser Arbeit werden, nach einer kurzen Rekapitulation der funktionellen und bildmorphologischen Neuroanatomie, die Indikationen zur praechirurgischen fMRT bei Patienten mit rolandischen Hirntumoren dargestellt. Ein robustes Basisprotokoll erlaubt zuverlaessig praechirurgische fMRT-Untersuchungen waehrend kontralateraler Handbewegungen auf klinischen MR-Tomographen mit Feldstaerken ab 1,0 Tesla. Optimierte Untersuchungsstrategien und praktikable Stimulationsmodalitaeten werden fuer Patienten mit ''handferner'' rolandischer Tumorlokalisation, vorbestehenden sensorimotorischen Defiziten oder mangelnder Kooperationsfaehigkeit vorgestellt und in der Anwendung durch Fallbeispiele veranschaulicht. Moeglichkeiten und Grenzen der klinischen Anwendung werden aufgezeigt und diskutiert. (orig.)

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

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

    2014-08-15

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

  7. Comparison of MultiHance {sup trademark} and Gadovist {sup trademark} for cerebral MR perfusion imaging in healthy volunteers; Vergleich von MultiHance {sup trademark} und Gadovist {sup trademark} zur zerebralen MR-Perfusionsmessung bei gesunden Probanden

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    Essig, M.; LeHuu, M.; Huebener, M.; Kaick, G. van [Deutsches Krebsforschungszentrum, Abt. Radiologische Diagnostik und Therapie, Heidelberg (Germany); Lodemann, K.P. [Bracco-Byk, Gulden (Germany); Schoenberg, S.O. [Institut fuer Klinische Radiologie, Ludwig-Maximilians-Universitaet Muenchen, Grosshadern (Germany)

    2002-11-01

    To evaluate the weakly protein interacting MR contrast agent MultiHance {sup trademark} and the one-molar agent Gadovist {sup trademark} for cerebral perfusion MR imaging, a randomized intraindividual study was conducted in 12 healthy male volunteers. Perfusion-MRI was performed with single and double dose of each contrast agent on a 1.5T MR system using a gradient-echo EPI sequence. The imaging parameters, slice positioning and contrast media application were standardized. For the quantitative assessment rCBV and rCBF measurements of gray and white matter were performed. Additionally, the percentage of signal drop and the full width half maximum (FWHM) of ROI signal time curves were quantified. In a qualitative analysis the image quality of the rCBV and rCBF maps were assessed.Single dosage of the used new contrast agents was sufficient to achieve high quality perfusion maps. The susceptibility effect, described by percentage of signal loss (Gadovist {sup trademark} : 29.4% vs. MultiHance {sup trademark} : 28.3%) and the FWHM (Gadovist {sup trademark} : 6.4 s vs. Multihance {sup trademark} : 7.0 s) were not different between the agents for single dose.The one molar MR contrast agent Gadovist {sup trademark} has no advantages over MultiHance {sup trademark}, a MR contrast agent with a higher relaxivity in perfusion MRI. Both agents allow the calculation of high quality perfusion maps at a dosage of 0.1 mmol/kg bw with physiologic absolute values for regional CBV and CBF. The susceptibility effect is comparable for both agents and stronger than with conventional MR contrast media. (orig.) [German] Zur Evaluierung des gering proteinbindenden MR-Kontrastmittels MultiHance {sup trademark} und des einmolaren MR-Kontrastmittels Gadovist {sup trademark} fuer die MR-Perfusionsmessung im Gehirn wurden in einer randomisierten, intraindividuellen Vergleichsstudie 12 gesunde maennliche Probanden untersucht. Die Perfusionsmessung wurde an einem 1,5-T-MRT mit einer T2

  8. BEI Resource Repository

    Data.gov (United States)

    U.S. Department of Health & Human Services — BEI Resources provides reagents, tools and information for studying Category A, B, and C priority pathogens, emerging infectious disease agents, non-pathogenic...

  9. Biogenic Emission Inventory System (BEIS)

    Science.gov (United States)

    Biogenic Emission Inventory System (BEIS) estimates volatile organic compound (VOC) emissions from vegetation and nitric oxide (NO) emission from soils. Recent BEIS development has been restricted to the SMOKE system

  10. Cardiovascular magnetic resonance: myocardial perfusion

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    Nagel, E.; Al-Saadi, N.; Fleck, E. [Dept. of Internal Medicine/Cardiology, German Heart Inst. Berlin and Charite, Campus Virchow, Humboldt Univ. (Germany)

    2000-06-01

    There is growing evidence that the noninvasive assessment of myocardial perfusion with cardiovascular magnetic resonance is a valid and accurate tool for the assessment of ischemic heart disease and its introduction into routine clinical evaluation of patients is rapidly expected. Magnetic resonance measurements allow the evaluation of reversible and irreversible myocardial ischemia, the assessment of acute myocardial infarction, as well as the recognition and detection of viable myocardium. Magnetic resonance perfusion measurements are mainly performed with T1-shortening contrast agents such as gadolinium-DTPA either by visual analysis or based on the analyses of signal intensity time curves. For the detection of myocardial ischemia the first pass kinetics of a gadolinium-DTPA bolus and for the detection of myocardial necrosis and the definition of viable myocardium steady state distribution kinetics are assessed. Quantitative analysis of myocardial perfusion can be performed but requires complex modeling due to the characteristics of gadolinium-DTPA. Thus, semi-quantitative parameters are preferred. There is accumulating evidence in the literature that magnetic resonance imaging can be used for the detection of coronary artery stenosis with high diagnostic accuracy both with semi-quantitative or visual analysis. Myocardial infarction can be reliably detected and the infarcted area determined. Non-reperfused infarcted myocardium can be differentiated from reperfused myocardium by different enhancement patterns that correlates with viability. (orig.) [German] Die Magnetresonanztomographie (MR) erlangt bei der nichtinvasiven Diagnostik der koronaren Herzerkrankung eine zunehmende Bedeutung. Mit dieser Technik koennen sowohl die globale und regionale Myokardfunktion als auch die myokardiale Perfusion exakt beurteilt werden. Bisher liegen die meisten Daten fuer die Analyse von Wandbewegungsstoerun-gen unter Belastung vor, wobei sich eine deutliche diagnostische

  11. Verkehrsmanagement bei Katastrophen

    OpenAIRE

    Hohloch, Marc; Nippold, Ronald

    2013-01-01

    DLR-Luftbilder zeigen Ausmaß der Überflutungen n einem vierstündigen Marathonflug hat das Forschungsflugzeug Do 228-212 des Deutschen Zentrums für Luft- und Raumfahrt (DLR) Luftbilder des Donauhochwassers in Bayern sowie der Elbe-, Saale- und Muldefluten in Sachsen und Sachsen-Anhalt aufgenommen. Das Flugzeug startete vom DLR-Standort Oberpfaffenhofen bei München. Es trug ein spezielles Kamerasystem für Luftaufnahmen in Katastrophengebieten an Bord, das im Projekt VABENE (Verkehrsmanageme...

  12. Knochenstoffwechsel bei malignen Erkrankungen

    Directory of Open Access Journals (Sweden)

    Keck A-V

    2003-01-01

    Full Text Available Bei malignen Erkrankungen, wie dem Mammakarzinom, dem Prostatakarzinom, dem Bronchialkarzinom oder dem multiplen Myelom ist der Knochen eines der am häufigsten von Metastasen betroffenen Organe. Das klinische Beschwerdebild ist durch das Auftreten pathologischer Frakturen, Schmerzen und Hyperkalzämien gekennzeichnet. Eine erhöhte Knochenresorptionsrate und Verlust an Knochenmasse im Sinne von osteoporoseartigen Veränderungen bedingt durch eine inadäquat überschießende Osteoklastendifferenzierung und -aktivierung sind ursächlich dafür verantwortlich. Durch jüngst publizierte Ergebnisse diverser Studien und Untersuchungen konnten die genauen Mechanismen der Rekrutierung und Aktivierung von Osteoklasten weiter aufgeklärt werden. Receptor activator of nuclear factor-kappa-B ligand (RANKL, ein Mitglied der Tumor necrosis factor (TNF Superfamilie konnte als entscheidender Faktor in der Osteoklastengenese identifiziert werden. Die Interaktion von RANKL mit seinem Rezeptor RANK (receptor activator of nuclear factor-kappa-B induziert die Entwicklung der osteoklastären Reihe aus dem hämatopoetischen Kompartment und fördert weiters die Differenzierung zu Osteoklastenvorstufen und die Aktivierung reifer Osteoklasten, ebenso wird eine verzögert einsetzende Apoptose bewirkt. Neben RANK und RANKL ist Osteoprotegerin (OPG als dritte Komponente in der Regulation der Knochenresorption involviert. Als Mitglied der TNF-Superfamilie bindet OPG an RANKL und blockiert somit alle stimulierenden Effekte von RANK auf die Osteoklastenentwicklung und neutralisiert so alle biologischen Effekte von RANKL. Diverse Hormone und Zytokine üben durch die Modifikation der Ratio von RANKL zu OPG einen regulatorischen Effekt auf die Knochenresorption aus. Diese ist bei osteolytischen Knochenmetastasen, beim multiplen Myelom und bei der malignen Hyperkalzämie erhöht. Das Gleichgewicht knochenaufbauender wie -abbauender Mechanismen scheint somit durch die Ratio von

  13. MRI of pulmonary perfusion; MRT der Lungenperfusion

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

    2006-04-15

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

  14. Die Bandscheibenprothese bei schmerzhafter Diskusdegeneration

    Directory of Open Access Journals (Sweden)

    Ogon M

    2004-01-01

    Full Text Available Bandscheibenprothesen sind indiziert bei Patienten mit einer schmerzhaften Bandscheibendegeneration, einer sogenannten DDD (degenerative disc disease, bei gut erhaltenen Facettengelenken. Kontraindikationen stellen eine Instabilität, eine Spondylarthrose, eine spinale Stenose und eine Osteoporose dar. Bei 19 Patienten mit einem Follow-up von mindestens 12 Monaten fand sich eine durchschnittliche Verbesserung des Oswestry Disability Index von präoperativ 50,8 auf 19,8. Der SF-36 Score zur Erfassung der Lebensqualität besserte sich von 31,5 auf 48,8 (Physical Component Summary Score bzw. von 37,8 auf 44,5 (Mental Component Summary Score im 1-Jahres-Follow-up. Nachhaltige Komplikationen traten nicht auf. Bandscheibenprothesen können heute bei Patienten mit therapieresistenten Kreuzschmerzen als gute Alternative zu einer Wirbelfusion angesehen werden.

  15. Mehrfacheffekt-Feuchtluftdestillation bei Umgebungsdruck

    OpenAIRE

    Müller-Holst, Hendrik

    2007-01-01

    Ein neuartiges Verfahren zur Feuchtluftdestillation mittels Verdunstung und Kondensation in einer einzigen Kammer wurde im Rahmen der Arbeit umfassend analysiert. Das Verfahren arbeitet bei Umgebungsdruck; der dadurch bei Temperaturen unter dem Siedepunkt verringerte Stoffübergang wird durch große Austauschflächen mit hoher Packungsdichte kompensiert. Der Transport der im Verdunster beladenen Feuchtluft zum Kondensator erfolgt innerhalb einer optimierten geometrischen Anordnung der Baueinheit...

  16. Syntaktische Störungen bei Aphasie

    OpenAIRE

    Penke, Martina

    2013-01-01

    1 Einleitung 2 Syntaktische Beeinträchtigung bei Broca-Aphasie 3 Syntaktische Beeinträchtigung bei Wernicke-Aphasie 4 Eine Charakterisierung der syntaktischen Beeinträchtigung bei Broca- und Wernicke-Aphasie 5 Resümee 6 Literatur

  17. : Myocardial Perfusion

    OpenAIRE

    Dacher, Jean-Nicolas; Lefebvre, V.; Dubourg, Bernard; Deux, Jean-François; Caudron, Jérôme

    2013-01-01

    International audience; The analysis of myocardial perfusion is a key step in the cardiac MRI examination. In routine work, this exploration carried out at rest is based on the qualitative first pass study of gadolinium with an ECG-triggered saturation recovery bFFE sequence. In view of recent knowledge, the analysis of the myocardial perfusion under vasodilator stress may be carried out by scintigraphy or MRI, the latter benefiting from the absence of exposure to ionizing rays and a lower co...

  18. 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

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    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.)

  19. Behandlungsergebnisse der Mikrochirurgie bei obstruktiver Azoospermie

    Directory of Open Access Journals (Sweden)

    Spenner A

    2006-01-01

    Full Text Available Einführung: Diese Arbeit stellt die Erfahrungen eines Operateurs an einem Spital mit der Mikrochirurgie der Samenwege vor. Die Behandlungsergebnisse und deren Vergleich zur künstlichen Befruchtung werden anhand aktueller Veröffentlichungen diskutiert. Patienten und Methode: Zwischen 1994 und 2004 wurde bei 90 Patienten mit Verschlußazoospermie (VAS eine Wiederherstellung der Samenwege vorgenommen (64 Patienten mit Status nach Vasektomie, 26 Patienten VAS anderer Genese. Postoperativ wurde das Spermiogramm analysiert und das Auftreten einer Schwangerschaft der Partnerin telefonisch erfragt. Ergebnisse: Nach Vasektomieumkehrung waren bei 89 % der Patienten die Samenwege durchgängig. Die Schwangerschaftsrate betrug bei den Patienten nach Vasektomieumkehrung 48 % und die Geburtenrate 45 %. Bei 16 von den 26 Patienten (62 % mit VAS anderer Ursache war eine Herstellung der Samenwegskontinuität technisch möglich. Jedoch zeigte die Hodenbiopsie bei 3 von diesen 16 Patienten eine Hypospermatogenese. Die postoperative Offenheitsrate der Samenwege der verbleibenden 13 Patienten mit VAS anderer Genese betrug 11/13 (85 %, die Schwangerschaftsrate 5/13 (39 %. Die Komplikationsrate im Sinne eines Wundhämatoms bei den insgesamt 90 Patienten lag bei 3/90 (3 %. Diskussion: Die beschriebenen Offenheits- und Schwangerschaftsraten liegen im Rahmen international publizierter Daten. Im Hinblick auf die Schwangerschaftsrate, die Behandlungskosten und Komplikationsrate ist die mikrochirurgische Wiederherstellung der Samenwege nach Vasektomie der künstlichen Befruchtung mittels ICSI (intracytoplasmatic sperm injection überlegen. Bei einem Alter der Partnerin 37 Jahre, einem weiblichen Infertilitätsfaktor, einer Samenwegsverschlußzeit 15 Jahre nach Vasektomie oder einem Verschluß der Samenwege aus anderer Genese als Vasektomie sollte die Wahl der Methode zur Ermöglichung einer Schwangerschaft individualisiert werden. Schlußfolgerung: Die Mikrochirurgie der

  20. Menopausale Hormontherapie (MHT bei internistischen Erkrankungen

    Directory of Open Access Journals (Sweden)

    Birkhäuser M

    2014-01-01

    Full Text Available Postmenopausale Frauen leiden zusätzlich zu klimakterischen Beschwerden oft an internistischen Grundkrankheiten. Daher ist es wichtig zu wissen, wann eine Hormonsubstitution (Menopausale Hormontherapie [MHT] in welcher Form verordnet werden darf, wenn mit nichthormonalen Alternativen keine genügende Besserung erzielt werden kann, und wo eine MHT kontraindiziert ist. Zur Verminderung des Risikos einer MHT bei internistischen Grundkrankheiten gelten folgende Grundregeln: – Beginn der MHT innerhalb des „günstigen Fensters“ ( 60 Jahren resp. innert 10 Jahre ab Menopause, außer bei den Kontraindikationen Angiopathie, Koronaropathie und bei anderen vaskulären Pathologien. – Verwenden der niedrigsten wirksamen Dosis, wenn möglich = 50 μg Östradiol/Tag transdermal resp. = 2 mg Östradiol/Tag peroral. Praktisch alle bekannten Nebenwirkungen der MHT sind dosisabhängig. – Bei alleinigen urogenitalen Symptomen nur vaginal-lokale Östrogengabe einsetzen. – Zahlreiche internistische Krankheiten werden durch Leberfaktoren beeinflusst oder induzieren selbst Veränderungen bestimmter Leberparameter (z. B. Gerinnungsfaktoren, Renin-Angiotensin-Aldosteron-System. Deshalb ist zur Vermeidung eines unerwünschten First-Pass-Effektes eine transdermale Östradiolgabe (Pflaster oder Gel vorzuziehen. – Bei kombinierter MHT soll außer bei speziellen Indikationen ein metabolisch neutrales Gestagen wie Progesteron, Dydrogesteron oder Dienogest gewählt oder Norethisteronacetat transdermal verabreicht werden. Gestagene mit glukokortikoider Partialwirkung wie Medroxyprogesteronacetat sind außer als Kurzzeitgabe zu vermeiden, v. a. bei erhöhtem Thromboserisiko. – Drospirenon besitzt eine antimineralokortikoide Wirkung, die bei erhöhtem Blutdruck gezielt eingesetzt werden kann. – Zyklische Schwankungen der Serumspiegel sind zu vermeiden und deshalb statt einer sequenziellen eine kontinuierlich-kombinierte MHT durchzuführen. Dabei kann das Gestagen auch

  1. CT Perfusion of the Head

    Science.gov (United States)

    ... Site Index A-Z CT Perfusion of the Head Computed tomography (CT) perfusion of the head uses ... the Head? What is CT Perfusion of the Head? Computed tomography (CT) perfusion imaging shows which areas ...

  2. Entwicklungstrends bei landwirtschaftlichen Applikationen - ein Zwischenfazit

    Directory of Open Access Journals (Sweden)

    Christa Hoffmann

    2014-10-01

    Full Text Available Globalisierung, volatile Märkte und der vermehrte Rückzug der Agrarpolitik aus der Marktregulierung sorgen dafür, dass die Entscheidungsfindungsprozesse auf landwirtschaftlichen Betrieben an Komplexität zunehmen. Applikationen bieten durch ihre Mobilität und individuellen Ausgestaltungsmöglichkeiten Optionen, um den Landwirt bei seiner täglichen Arbeit zu unterstützen. In diesem Kontext nimmt diese Arbeit eine Bestandsaufnahme und Kategorisierung nativer Applikationen mit landwirtschaftlichem Bezug vor. Die Ergebnisse zeigen unter anderem einen Angebotsschwerpunkt im Produktionszweig Pflanzenbau und bei den Funktionen bestimmte häufig auftretende bedarfsbedingte Kombinationen (z. B. Planung und Analyse.

  3. Intra-axial brain tumors in adults. On the basis of the 2016 WHO classification; Intraaxiale Hirntumoren des Erwachsenenalters. Auf der Basis der WHO-Klassifizierung 2016

    Energy Technology Data Exchange (ETDEWEB)

    Peitgen, N.; Papanagiotou, P. [Klinikum Bremen-Mitte/Bremen-Ost, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Bremen (Germany)

    2017-09-15

    The influence of the World Health Organization (WHO) classification from 2016 on the radiological diagnosis for tumors of the central nervous system (CNS) in adults. Computed tomography (CT), magnetic resonance imaging (MRI) and MR spectroscopy. In order to come as close as possible to the correct diagnosis of CNS tumors, MRI is the long-standing accepted method of choice that can in some cases be supported by the use of CT to demonstrate calcification or bone destruction. In individual cases MRI spectroscopy can be helpful for the differentiation between neoplasms and inflammatory lesions or surveillance of tumor therapy, just as perfusion, which is not discussed in this article. (orig.) [German] Einfluss der WHO-Klassifikation von 2016 fuer ZNS-Tumoren auf die radiologische Befunderstellung fuer ZNS-Tumoren des Erwachsenenalters. CT, MRT, MR-Spektroskopie. Um sich der korrekten Diagnose bzgl. eines ZNS-Tumors bestmoeglich zu naehern, ist die MRT das akzeptierte Standardverfahren, die in Einzelfaellen durch eine CT ergaenzt werden kann, wenn Verkalkungen oder knoecherne Arrosionen dargestellt werden sollen. Eine MR-Spektroskopie kann in Einzelfaellen zur Differenzierung von Neoplasien und entzuendlichen Veraenderungen oder Tumorverlaufskontrollen unter Therapie hilfreich sein, ebenso wie die Perfusion, auf die in diesem Artikel nicht eingegangen wird. (orig.)

  4. KRITIK SOSIAL DALAM KOMIK STRIP PAK BEI

    Directory of Open Access Journals (Sweden)

    Yudhi Novriansyah

    2016-08-01

    Full Text Available This research aimed to do interpret the marking which flange social criticism and know laboring ideology in story of Comic Strip Pak Bei. Research based on theory of structural semiotic according to Ferdinand De Saussure. Using analysis of Syntagmatic as first level of meaning to the text network and also picture, and analysis of Paradigmatic as second level of meaning or implicit meaning (connota-tion, myth, ideology Analysis done to six Comic choice edition of Strip Pak Bei period of November 2004 - Februari 2005 which tend to flange social criticism. At band of syntagmatic, result of research indicate that story theme lifted from social problems that happened in major society. The fact clear progressively when connected by Intertextual with information and texts which have preexisted. At band of Paradigmatic, social criticism tend to emerge dimly, is not transparent. Because of Comic Strip Pak Bei expand in the middle of Java cultural domination that developing myth of criticize as action menacing compatibility and orderliness of society. Story of Comic Strip Pak Bei also confirm dominant ideology in Java society culture, namely ideology of Patriarkhi and Feudalism which still go into effect until now. This prove ideology idea according to Louis Althusser which not again opposition between class, but have been owned and practiced by all social class.

  5. Pilzinfektionen des Zentralnervensystems bei immunkompetentem Wirt

    NARCIS (Netherlands)

    Tintelnot, K.; de Hoog, G.S.; Haase, G.

    2014-01-01

    Die Mehrzahl von Pilzinfektionen, die zu mykotischen Tumoren führen und bei Patienten ohne jegliche prädisponierende Vorerkrankung auftreten, wird durch Cryptococcus gattii bzw. C. neoformans oder durch Schwärzepilze, insbesondere durch Cladophialophora bantiana, Ramichloridium mackenziei, Exophiala

  6. Verantwortlichkeits- und Schuldzuschreibungen bei Ost- und Westdeutschen

    OpenAIRE

    Janetzko, Elke; Schmitt, Manfred

    1992-01-01

    An einer Stichprobe von 140 Westdeutschen und 147 Ostdeutschen wurde die Hypothese untersucht, ob Ostdeutsche aufgrund der restriktiven gesellschaftlichen Rahmenbedingungen in der DDR zu geringeren Selbstzuschreibungen von Verantwortlichkeit und Schuld bei Schadensereignissen des öffentlichen Lebens neigen als Westdeutsche. In einem experimentellen Fragebogen wurden vier Schadensszenarien geschildert, zwei aus dem privaten (Auto, Schrebergarten) und zwei aus dem öffentlichen Leben (Trinkwasse...

  7. Analytische Kinder- und Jugendlichenpsychotherapie bei Schulverweigerung

    OpenAIRE

    Oelsner, Wolfgang

    2003-01-01

    Das Phänomen Schulverweigerung wird differentialdiagnostisch unter Schulschwänzen, Schulangst und Schulphobie diskutiert. Analytische Kinder- und Jugendlichenpsychotherapie wird vorrangig bei Schulphobie indiziert gesehen. Es handelt sich um eine Trennungsangst des Kindes, die in dyadischen Beziehungsstrukturen fixiert ist. Um einen Triangulierungsprozess therapeutisch zu forcieren, dürfen die als Verweigerung ausagierten Widerstände sich nicht weiter etablieren. Wenn es nicht zu...

  8. Analytische Kinder- und Jugendlichenpsychotherapie bei Schulverweigerung

    OpenAIRE

    Oelsner, Wolfgang

    2003-01-01

    Das Phänomen Schulverweigerung wird differentialdiagnostisch unter Schulschwänzen, Schulangst und Schulphobie diskutiert. Analytische Kinder- und Jugendlichenpsychotherapie wird vorrangig bei Schulphobie indiziert gesehen. Es handelt sich um eine Trennungsangst des Kindes, die in dyadischen Beziehungsstrukturen fixiert ist. Um einen Triangulierungsprozess therapeutisch zu forcieren, dürfen die als Verweigerung ausagierten Widerstände sich nicht weiter etablieren. Wenn es nicht zur baldigen Au...

  9. Pharmakotherapie bei niereninsuffizienten Patienten und unter Dialysebehandlung

    Directory of Open Access Journals (Sweden)

    Maus S

    2011-01-01

    Full Text Available Noch zu viele Kollegen kennen nur 2 Stadien der Niereninsuffizienz: die „kompensierte“ und die dekompensierte Niereninsuffizienz. Es setzt sich aber immer mehr durch, die chronische Niereninsuffizienz (CKD in 5 Stadien einzuteilen. Etwa 20 % aller Patienten in einer Klinik haben eine eingeschränkte Nierenfunktion, die oft wegen des kreatininblinden Bereichs nicht erkannt wird. Bei Antidiabetika oder Antihypertensiva macht es durchaus Sinn, nierenunabhängige Alternativpräparate wie Gliquidon oder Metoprolol, einzusetzen. Klassische Beispiele für die Notwendigkeit einer Dosisanpassung sind Antibiotika und antivirale Substanzen. Immer häufiger wird die Dosisanpassung von Zytostatika bei Tumorpatienten mit eingeschränkter Nierenfunktion nachgefragt. Die Dosisanpassung zielt darauf ab, die richtige Dosis und das richtige Dosierungsintervall zu finden. Nicht nur jeder Patient ist anders, sondern auch jedes Medikament. Trotzdem gelten bei jedem Patienten und für jedes Medikament einfache Gesetze. Pharmakokinetik und -dynamik formulieren solche Gesetze. Die Pharmakokinetik ist zwar eine notwendige, aber erst mit der Pharmakodynamik zusammen hinreichende Grundlage der Dosisanpassung.

  10. Laser doppler perfusion imaging

    International Nuclear Information System (INIS)

    Waardell, K.

    1992-01-01

    Recording of tissue perfusion is important in assessing the influence of peripheral vascular diseases on the microcirculation. This thesis reports on a laser doppler perfusion imager based on dynamic light scattering in tissue. When a low power He-Ne laser beam sequentally scans the tissue, moving blood cells generate doppler components in the back-scattered light. A fraction of this light is detected by a photodetector and converted into an electrical signal. In the processor, a signal proportional to the tissue perfusion at each measurement site is calculated and stored. When the scanning procedure is completed, a color-coded perfusion image is presented on a monitor. To convert important aspects of the perfusion image into more quantitative parameters, data analysis functions are implemented in the software. A theory describing the dependence of the distance between individual measurement points and detector on the system amplification factor is proposed and correction algorithms are presented. The performance of the laser doppler perfusion imager was evaluated using a flow simulator. A linear relationship between processor output signal and flow through the simulator was demonstrated for blood cell concentrations below 0.2%. The median sampling depth of the laser beam was simulated by a Monte Carlo technique and estimated to 235 μm. The perfusion imager has been used in the clinic to study perfusion changes in port wine stains treated with argon laser and to investigate the intensity and extension of the cutaneous axon reflex response after electrical nerve stimulation. The fact that perfusion can be visualized without touching the tissue implies elimination of sterilization problems, thus simplifying clinical investigations of perfusion in association with diagnosis and treatment of peripheral vascular diseases. 22 refs

  11. MRI of myocardial perfusion.

    Science.gov (United States)

    Jerosch-Herold, Michael; Muehling, Olaf; Wilke, Norbert

    2006-02-01

    An overwhelming number of myocardial perfusion studies are done by nuclear isotope imaging. Magnetic resonance imaging during the first pass of an injected, contrast bolus has some significant advantages for detection of blood flow deficits, namely higher spatial resolution, absence of ionizing radiation, and speed of the test. Previous clinical studies have demonstrated that excellent sensitivity and specificity can be achieved with MR myocardial perfusion imaging for detecting coronary artery disease, and assessment of patients with acute chest pain. Furthermore, an absolute quantification of myocardial blood flow is feasible, as was demonstrated by comparison of MR perfusion imaging, to measurements with isotope labeled microspheres in experimental models. An integrated assessment of perfusion, function, and viability, is thus feasible by MRI to answer important clinical challenges such as the identification of stunned or hibernating, but viable myocardium.

  12. Measuring myocardial perfusion

    DEFF Research Database (Denmark)

    Qayyum, A A; Kastrup, J

    2015-01-01

    Recently, focus has changed from anatomical assessment of coronary arteries towards functional testing to evaluate the effect of stenosis on the myocardium before intervention. Besides positron-emission tomography (PET), cardiac MRI (CMR), and cardiac CT are able to measure myocardial perfusion......-known and is used in routine clinical practice. However, PET uses radioactive tracers and has a lower spatial resolution compared to CMR and CT. CMR and CT are emerging techniques in the field of myocardial perfusion imaging. CMR uses magnetic resonance to obtain images, whereas CT uses x-rays during first....... Myocardial perfusion abnormalities are the first sign of the ischaemic cascade in the development of coronary artery disease (CAD). PET is considered the non-invasive clinical reference standard for absolute quantification of myocardial perfusion. The diagnostic and prognostic value of PET is well...

  13. Orale L-Carnitin-Supplementierung bei Hochleistungskühen

    OpenAIRE

    Glatz, Martin

    2015-01-01

    Einleitung: L-Carnitin spielt eine zentrale Rolle im Energiestoffwechsel. Da dieser in der Frühlaktation bei Hochleistungskühen besonders beansprucht und z.T. überlastet wird, ergibt sich die Frage, ob durch L-Carnitinsupplementation ein stabilerer Stoffwechsel und damit bessere Leistungen erreicht werden können. Zielstellung: Es wurde geprüft, ob bei Hochleistungskühen mit einer mittleren Milchleistung von 12000 kg/Jahr die orale Supplementation von L Carnitin im peripartalem Zeitraum bei...

  14. Die Kyphoplastie als Revisionseingriff bei Auslockerung eines Fixateurs interne bei Osteoporose

    Directory of Open Access Journals (Sweden)

    Becker S

    2004-01-01

    Full Text Available Kyphoplastie ist eine moderne minimal-invasive Methode zur Stabilisation von osteoporotischen Wirbelfrakturen. Bei einigen osteoporotischen Patienten kann aber eine offene Stabilisation mit Fixateur interne notwendig werden. Aufgrund des osteoporotischen Knochens sind diese Eingriffe mit einem hohen Schraubenauslockerungsrisiko behaftet. Wir demonstrieren diesbezüglich 3 verschiedene Techniken zur Stabilisierung einer osteoporotischen Wirbelsäule nach Schraubenausbruch: die transpedikuläre Kyphoplastie nach Schraubenentfernung, die kyphoplastische Schraubenaugmentationsmethode und die kyphoplastische Abstützungsmethode.

  15. Overcoming the Challenges of BeiDou Receiver Implementation

    Directory of Open Access Journals (Sweden)

    Mohammad Zahidul H. Bhuiyan

    2014-11-01

    Full Text Available Global Navigation Satellite System (GNSS-based positioning is experiencing rapid changes. The existing GPS and the GLONASS systems are being modernized to better serve the current challenging applications under harsh signal conditions. These modernizations include increasing the number of transmission frequencies and changes to the signal components. In addition, the Chinese BeiDou Navigation Satellite system (BDS and the European Galileo are currently under development for global operation. Therefore, in view of these new upcoming systems the research and development of GNSS receivers has been experiencing a new upsurge. In this article, the authors discuss the main functionalities of a GNSS receiver in view of BDS. While describing the main functionalities of a software-defined BeiDou receiver, the authors also highlight the similarities and differences between the signal characteristics of the BeiDou B1 open service signal and the legacy GPS L1 C/A signal, as in general they both exhibit similar characteristics. In addition, the authors implement a novel acquisition technique for long coherent integration in the presence of NH code modulation in BeiDou D1 signal. Furthermore, a simple phase-preserved coherent integration based acquisition scheme is implemented for BeiDou GEO satellite acquisition. Apart from the above BeiDou-specific implementations, a novel Carrier-to-Noise-density ratio estimation technique is also implemented in the software receiver, which does not necessarily require bit synchronization prior to estimation. Finally, the authors present a BeiDou-only position fix with the implemented software-defined BeiDou receiver considering all three satellite constellations from BDS. In addition, a true multi-GNSS position fix with GPS and BDS systems is also presented while comparing their performances for a static stand-alone code phase-based positioning.

  16. Osteoporose bei Spondylitis ankylosans - Einfluß von Lebensgewohnheiten

    Directory of Open Access Journals (Sweden)

    Aglas F

    2004-01-01

    Full Text Available Krankheitsbedingte Artefakte können bei der SpA (Spondylitis ankylosans; Mb. Bechterew die Sensitivität einer Knochendichtemessung im Lumbalbereich beeinträchtigen. Das bei dieser rheumatischen Erkrankung bekannte Osteoporoserisiko ist neben genetischen Faktoren und Entzündungsmechanismen auch von verschiedenen exogenen Einflüssen abhängig. An 47 SpA-Patienten wurde mittels DEXA eine vergleichende Knochendichtemessung (BMD an der Hüfte (Schenkelhals und Ward'sches Dreieck sowie im Bereich der Wirbelsäule (L1-L4 vorgenommen. Zusätzlich erfolgte eine Erhebung der Lebens-Ernährungsgewohnheiten der SpA-Patienten in bezug auf die BMD, um exogene Einflüsse erfassen zu können. Die Knochendichtemessungen ergaben an der LWS wesentlich häufiger eine BMD im Normbereich als am proximalen Femur. Besonders deutliche Unterschiede traten im höheren Lebensalter auf, bei dem aufgrund von Kalzifizierungsvorgängen und Syndesmophyten an der LWS fälschlicherweise eine Dichtezunahme vorgetäuscht wird. Es kann daher bei SpA empfohlen werden, die wesentlich sensitivere Dichtemessung am Schenkelhals durchzuführen. Die über einen Zeitraum von 3 Jahren beobachteten, signifikant erhöhten, medianen CRP-Spiegel zeigen, daß eine permanente Aktivierung von Entzündungsprozessen bei SpA auch einen negativen Faktor betreffend des Knochenmasseverlustes darstellt. Die Analyse der Lebensgewohnheiten ergab, daß SpA-Patienten mit normaler BMD ausnahmslos regelmäßig kalziumreiche Nahrungsmittel zu sich nehmen; bei verminderter BMD wurde in der Mehrheit ein fehlender Konsum an Milchprodukten beobachtet. Leider war auch mit abnehmender BMD eine Verminderung der bei SpA empfohlenen Bewegungsübungen festzustellen. Aufgrund der Resultate ergibt sich eine generelle Empfehlung zu regelmäßigen Bewegungsübungen plus Osteoporosediät bei allen Bechterew-Patienten.

  17. Extremity perfusion for sarcoma

    NARCIS (Netherlands)

    Hoekstra, Harald Joan

    2008-01-01

    For more than 50 years, the technique of extremity perfusion has been explored in the limb salvage treatment of local, recurrent, and multifocal sarcomas. The "discovery" of tumor necrosis factor-or. in combination with melphalan was a real breakthrough in the treatment of primarily irresectable

  18. Isolated limb perfusion.

    Science.gov (United States)

    Gillespie, Rosalyn; Chantier, Nariane

    1994-12-08

    Growing concern over the rising incidence of malignant melanoma has brought about a need for information on this disorder and the treatment available. Isolated limb perfusion is a relatively new technique used in only a few hospitals. An increased knowledge base will lead to a better understanding of the nursing care required and to a more in-depth care plan.

  19. Untersuchungen zur Rolle von Neurozytokinen in Hirntumoren

    OpenAIRE

    Züchner, Stephan

    2001-01-01

    Ciliary Neurotrophic Factor (CNTF) and Interleukin-6 (IL-6) influence the survival and the differentiation of neuronal and glial cells. CNTF induces reactive transformation of astrocytes in vivo and has been shown to promote proliferation of neuronal tumor cell lines in vitro. Thus, CNTF is a candidate growth and/or differentiation factor for neuronal and glial tumors. Effects of neurocytokines are mediated trough specific receptor components. In this study the expression of CNTF and IL-6 and...

  20. Framework for radiation pneumonitis risk stratification based on anatomic and perfused lung dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Dhami, Gurleen; Zeng, Jing; Patel, Shilpen A.; Rengan, Ramesh [University of Washington School of Medicine, Department of Radiation Oncology, Seattle, WA (United States); Vesselle, Hubert J.; Kinahan, Paul E.; Miyaoka, Robert S. [University of Washington School of Medicine, Department of Radiology, Seattle, WA (United States); Bowen, Stephen R. [University of Washington School of Medicine, Department of Radiation Oncology, Seattle, WA (United States); University of Washington School of Medicine, Department of Radiology, Seattle, WA (United States)

    2017-05-15

    To design and apply a framework for predicting symptomatic radiation pneumonitis in patients undergoing thoracic radiation, using both pretreatment anatomic and perfused lung dose-volume parameters. Radiation treatment planning CT scans were coregistered with pretreatment [{sup 99m}Tc]MAA perfusion SPECT/CT scans of 20 patients who underwent definitive thoracic radiation. Clinical radiation pneumonitis was defined as grade ≥ 2 (CTCAE v4 grading system). Anatomic lung dose-volume parameters were collected from the treatment planning scans. Perfusion dose-volume parameters were calculated from pretreatment SPECT/CT scans. Equivalent doses in 2 Gy per fraction were calculated in the lung to account for differences in treatment regimens and spatial variations in lung dose (EQD2{sub lung}). Anatomic lung dosimetric parameters (MLD) and functional lung dosimetric parameters (pMLD{sub 70%}) were identified as candidate predictors of grade ≥ 2 radiation pneumonitis (AUC > 0.93, p < 0.01). Pairing of an anatomic and functional dosimetric parameter (e.g., MLD and pMLD{sub 70%}) may further improve prediction accuracy. Not all individuals with high anatomic lung dose (MLD > 13.6 GyEQD2{sub lung}, 19.3 Gy for patients receiving 60 Gy in 30 fractions) developed radiation pneumonitis, but all individuals who also had high mean dose to perfused lung (pMLD{sub 70%} > 13.3 GyEQD2) developed radiation pneumonitis. The preliminary application of this framework revealed differences between anatomic and perfused lung dosimetry in this limited patient cohort. The addition of perfused lung parameters may help risk stratify patients for radiation pneumonitis, especially in treatment plans with high anatomic mean lung dose. Further investigations are warranted. (orig.) [German] Erstellung und Anwendung eines Rahmenwerks zur Vorhersage symptomatischer Strahlenpneumonitis bei Patienten mit einer Thorax-Bestrahlung anhand anatomischer und perfundierter Lungendosis-Volumen-Parameter in der

  1. Development and Evaluation of the Biogenic Emissions Inventory System (BEIS) Model v3.6

    Science.gov (United States)

    We have developed new canopy emission algorithms and land use data for BEIS v3.6. Simulations with BEIS v3.4 and BEIS v3.6 in CMAQ v5.0.2 are compared these changes to the Model of Emissions of Gases and Aerosols from Nature (MEGAN) and evaluated the simulations against observati...

  2. Perfusion based cell culture chips

    DEFF Research Database (Denmark)

    Heiskanen, Arto; Emnéus, Jenny; Dufva, Martin

    2010-01-01

    Performing cell culture in miniaturized perfusion chambers gives possibilities to experiment with cells under near in vivo like conditions. In contrast to traditional batch cultures, miniaturized perfusion systems provide precise control of medium composition, long term unattended cultures...... and tissue like structuring of the cultures. However, as this chapter illustrates, many issues remain to be identified regarding perfusion cell culture such as design, material choice and how to use these systems before they will be widespread amongst biomedical researchers....

  3. Reverse ventilation--perfusion mismatch

    Energy Technology Data Exchange (ETDEWEB)

    Palmaz, J.C.; Barnett, C.A.; Reich, S.B.; Krumpe, P.E.; Farrer, P.A.

    1984-01-01

    Patients having lobar airway obstruction or consolidation usually have decreases of both ventilation and perfusion on lung scans. We report three patients in whom hypoxic vasoconstriction was apparently incomplete, resulting in a ''reversed'' ventilation-perfusion mismatch. Perfusion of the hypoxic lobe on the radionuclide scan was associated with metabolic alkalosis, pulmonary venous and pulmonary arterial hypertension in these patients.

  4. 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.)

  5. Perfusion Bioreactor Module

    Science.gov (United States)

    Morrison, Dennis R.

    1990-01-01

    Perfusion bioreactor module, self-contained, closed-loop cell-culture system that operates in microgravity or on Earth. Equipment supports growth or long-term maintenance of cultures of human or other fragile cells for experiments in basic cell biology or process technology. Designed to support proliferation (initially at exponential rates of growth) of cells in complex growth medium and to maintain confluent cells in defined medium under conditions optimized to permit or encourage selected functions of cells, including secretion of products of cells into medium.

  6. Myocardial perfusion modeling using MRI

    DEFF Research Database (Denmark)

    Larsson, H B; Fritz-Hansen, T; Rostrup, Egill

    1996-01-01

    In the present study, it is shown that it is possible to quantify myocardial perfusion using magnetic resonance imaging in combination with gadolinium diethylenetriaminopentaacetic acid (Gd-DTPA). Previously, a simple model and method for measuring myocardial perfusion using an inversion recovery...

  7. Nagelbefall kann bei Patienten mit Psoriasis auf eine Enthesiopathie hinweisen.

    Science.gov (United States)

    Castellanos-González, Maria; Joven, Beatriz Esther; Sánchez, Julio; Andrés-Esteban, Eva María; Vanaclocha-Sebastián, Francisco; Romero, Pablo Ortiz; Díaz, Raquel Rivera

    2016-11-01

    Obwohl subklinische Enthesiopathie ein gut etabliertes diagnostisches Merkmal der Psoriasisarthritis (PsA) ist, wird sie häufig übersehen, da viele Patienten asymptomatisch sind. Gäbe es klinische Hinweise auf das Vorliegen einer Enthesiopathie, würde dies den Klinikern die Möglichkeit eröffnen, eine PsA frühzeitig zu diagnostizieren. Es wurde eine monozentrische prospektive Studie mit insgesamt 90 Psoriasis-Patienten durchgeführt, um mittels Ultraschall das Vorliegen von Enthesenanomalien zu untersuchen und eine Korrelation mit dem Befall der Nägel festzustellen. Enthesenanomalien wurden bei 23 Patienten (25,5 %) gefunden, von denen 19 (82,6 %) Nagelbefall aufwiesen. Bei 4 Patienten waren die Nägel nicht betroffen. Enthesiopathie lag bei 31,1 % (19/61) der Patienten mit Onychopathie vor, von den Patienten ohne Nagelbefall litten nur 13,8 % (4/29) an Enthesiopathie (p = 0,07). Zwischen dem Target-NAPSI-Score und dem Vorliegen einer Enthesiopathie bestand eine signifikante Korrelation. Eine signifikante Korrelation bestand darüber hinaus auch zwischen dem Vorliegen einer Enthesiopathie und der Anzahl der betroffenen Nägel (p = 0,035). Klinische Belege für eine Onychopathie können der Schlüssel für die frühe Diagnose einer Enthesiopathie bei Psoriasis-Patienten sein. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  8. Innovative Development and Forecast of BeiDou System

    Directory of Open Access Journals (Sweden)

    TAN Shusen

    2017-10-01

    Full Text Available Due to the strong demand for satellite applications and rapid development of new space technology,the cross-integration of space-based radio systems has become a trend.BeiDou system started from two satellites to build China's first generation satellite navigation and positioning system with the features of fast location reporting(RDSSand short message communication(MSSservice.Then BeiDou technology frame combined with RNSS continuous navigation and RDSS location report,was constructed in eight years,and the coverage in Asia-Pacific was completed.Through effective satellite radio frequency compatible design and international coordination,BeiDou system is the first radio satellite system which includes RNSS,RDSS,MSS three major services,approved by International Telecommunication Union(ITUin the world.This paper expounds the development process,technical frame,main features and prospect of BeiDou system with three major services and four key functions,in the concept of innovation and transcendence.

  9. Radikale Operation bei Nierenkarzinom mit Tumorthrombose im rechten Herzvorhof

    Directory of Open Access Journals (Sweden)

    Morávek P

    2002-01-01

    Full Text Available Einleitung: Die Ansicht über eine radikale Operation bei Nierenkarzinom mit einer Tumorthrombose im rechten Herzvorhof ist in der Literatur bisher kontrovers. Nach Meinung der Autoren ist der Tumorthrombus in erster Linie ein ernsthaftes Problem der Operabilität. Sie entschieden sich für eine radikale Operation. Methode: Die Autoren operierten 11 Patienten im Zeitraum von 1978 bis 2001. Die grundlegenden Bedingungen für eine Operation waren die exakte Festlegung der Diagnose und des Stadiums der Erkrankung (T1-T3, N0, M0. Bei 9 Patienten haben die Autoren eine Entfernung des Tumorthrombus in extrakorporaler Zirkulation bei Kreislaufstillstand und bei 2 Kranken mittels kavoatrialem Shunt ohne Herz-Lungen-Maschine durchgeführt. Ergebnisse: 2 Patienten sind in der 2. bis 4. Woche nach der Operation gestorben, 1 Patientin ist 2 Jahre nach der Operation gestorben, 1 Patient ist nach 4 Jahren und 1 Patient nach 8 Jahren gestorben. 6 Patienten leben 1, 2, 3, 3,5, 3,5 und 5 Jahre nach der Operation. Schlußfolgerung: Die Voraussetzungen für eine erfolgreiche Operation sind die richtige Indikation, die Wahl der passenden Operationsmethode sowie die Zusammenarbeit von Urologen und Kardiochirurgen. Die Autoren halten eine Entfernung des Thrombus mittels Atriotomie sowie Kavotomie in extrakorporaler Zirkulation und tiefer Hypothermie mit Kreislaufstillstand für die beste Methode.

  10. Radiological diagnosis in epilepsy; Radiologische Diagnostik bei Epilepsie

    Energy Technology Data Exchange (ETDEWEB)

    Ostertun, B. [Radiologische Universitaetsklinik, Bonn (Germany). Magnetresonanztomographie

    1999-03-01

    Results: Hippocampal sclerosis, the most frequent cause of focal epilepsy, can be detected with 90-98% sensitivity by visual analysis and quantitative signal and volume measurement of the hippocampi in high-resolution coronal T{sub 2}-weighted MR images. Benign tumors, such as gangliogliomas and dysembryoplastic neuoepithelial tumors (DNT), as well as cortical dysplasias are frequently composed of cystic and solid parts, which may show calcification, but never edema. Bloodbrain-barrier disruption as seen in approximately 40% of the benign tumors are the only feature that allows to differentiate them from non-neoplastic dysplasias. In rare cases of totally calcified lesions, CT may be the only diagnostic imaging modality. Proton-density-weighted or FLAIR imaging is essential for the detection of small solid cortical lesion components, because they provide sufficient contrast with adjacent CSF. T{sub 1}-weighted inversion recovery images are most sensitive for the detection of migration and gyration abnormalities. The depiction of calcified lesions and hemosiderin deposits after trauma is most efficient with T{sub 2}* weighted gradient echo sequences. Conclusions: With further rapid improvent of high resolution MRI techniques, the near future will probably show that nearly 100% of focal epilepsies are caused by structural brain abnormalities. With refined imaging techniques applied, the sensitivity of neuroradiological evaluation is 90% at present. Therefore presurgical MRI plays a key role in epilespy surgery. (orig.) [Deutsch] Ergebnisse: Ammonshornsklerosen, die haeufigste Ursache fokaler Epilepsien, werden bei Anwendung hochaufloesender koronarer T{sub 2}-gewichteter Sequenzen durch visuelle Beurteilung und quantitative Messungen von Signal und Volumen der Hippocampi mit 90-98% Sensitivitaet nachgewiesen. Gutartige Tumoren wie Gangliogliome und dysembryoplastische neuroepitheliale Tumoren (DNT) sowie glioneuronale Hamartien weisen gehaeuft zystische Komponenten

  11. Pneumonia in immunosuppressed patients; Pneumonien bei immunsupprimierten Patienten

    Energy Technology Data Exchange (ETDEWEB)

    Solyanik, O.; Gaass, T.; Hellbach, K. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer klinische Radiologie, Muenchen (Germany); Dinkel, J. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer klinische Radiologie, Muenchen (Germany); Comprehensive Pneumology Center Munich (CPC-M), Muenchen (Germany)

    2017-01-15

    Pulmonary infections are a common complication in immunosuppressed patients with a frequently fatal prognosis despite modern prophylactic therapy. An early and correct diagnosis is important for initiation of the appropriate therapy. Chest radiography is the preferred initial imaging examination but is not accurate enough for the detection of pulmonary infections in immunosuppressed patients. Pneumonia is caused by a broad spectrum of pathogens in immunocompromised patients. In addition to imaging, the clinical history and epidemiology also play an important role in the diagnostics. Using epidemiological and anamnestic information, computed tomography (CT) shows a significantly better sensitivity and specificity particularly for the diagnosis of atypical forms of pneumonia. Due to the exact imaging of the different infiltration patterns CT provides an increased sensitivity with respect to the etiological classification of pulmonary infections. This article reviews in particular the radiological findings of commonly occurring pulmonary infections in immunosuppressed patients. (orig.) [German] Pneumonien bei immunsupprimierten Patienten sind haeufige Komplikationen, die trotzt moderner Prophylaxe toedlich verlaufen koennen. Eine korrekte Diagnose ist daher von entscheidender Bedeutung, um die richtige Therapie einleiten zu koennen. Die Roentgenthoraxaufnahme ist selten spezifisch genug fuer die genaue Einordnung atypischer Pneumonien in Folge einer Immunsuppression. Pneumonien unter Immunsuppression werden durch ein sehr breites Erregerspektrum verursacht. Eine wichtige Rolle bei der Diagnosefindung spielen neben der Bildgebung auch die klinische Anamnese und Epidemiologie. Mithilfe der klinischen Anamnese und Epidemiologie bietet die Computertomographie (CT) bei immunsupprimierten Patienten zum einen eine erhoehte Sensitivitaet bei der Detektion insbesondere atypischer Pneumonien. Zum anderen weist die CT durch die exakte Abbildung unterschiedlicher Infiltratmuster

  12. Osteoporose bei Mb. Bechterew - neue Ansätze

    Directory of Open Access Journals (Sweden)

    Obermayer-Pietsch B

    1999-01-01

    Full Text Available Eine axiale Osteoporose und daraus resultierende vertebrale Kompressionsfrakturen sind häufige Symptome eines Mb. Bechterew (MbB, Spondylarthritis ankylosans. Als ein möglicher genetischer Faktor der Osteoporose wurde eine Assoziation der Knochendichte (BMD mit BsmI- und FokI-Polymorphismen im Vitamin D-Rezeptor-(VDR-Gen publiziert. In der vorliegenden Studie wurden die Beziehungen zwischen diesen Polymorphismen, Knochenstoffwechsel, BMD und Aktivitätsindizes bei Patienten mit MbB untersucht. Bei 47 MbB-Patienten wurden Aktivitätsindizes und morphologische Parameter sowie BMD-Messungen (Dual-Röntgen-Absorptiometrie an Wirbelsäule und Schenkelhals im Vergleich zu 52 gesunden, altersgleichen Personen erhoben. Die Laborbestimmungen umfaßten biochemische Aktivitätsparameter, HLA-Typisierung sowie Knochenan- und -abbaumarker. Aus peripheren Leukozyten wurde genomische DNA präpariert und mittels Polymerase-Kettenreaktion (PCR und anschließender FokI- und BsmI-Restriktion der VDR-Genotyp nach vorhandenen bzw. fehlenden Schnittstellen (f/b bzw. F/B bestimmt. Bei MbB-Patienten fand sich eine Osteoporose deutlich häufiger als in der Kontrollgruppe. Eine Zuordnung von Aktivitätsindizes, BMD und Knochenstoffwechselparametern zu den Genotypen zeigte bei männlichen MbB-Patienten sowohl eine Assoziation der WS-Knochendichte als auch der Entzündungsmarker mit FokI-, nicht jedoch mit BsmI-Genotypen des VDR. Die pathophysiologischen Mechanismen dieser Assoziation, insbesondere mit der entzündlichen Aktivität des Mb. Bechterew, sind noch ungeklärt. Eine frühzeitige Erfassung des Osteoporoserisikos bei MbB-Patienten mittels molekularbiologischer Tests könnte eine rechtzeitige Prophylaxe und Therapie dieser Komplikation ermöglichen.

  13. Perfusion CT in acute stroke

    International Nuclear Information System (INIS)

    Eckert, Bernd; Roether, Joachim; Fiehler, Jens; Thomalla, Goetz

    2015-01-01

    Modern multislice CT scanners enable multimodal protocols including non-enhanced CT, CT angiography, and CT perfusion. A 64-slice CT scanner provides 4-cm coverage. To cover the whole brain, a 128 - 256-slice scanner is needed. The use of perfusion CT requires an optimized scan protocol in order to reduce exposure to radiation. As compared to non-enhanced CT and CT angiography, the use of CT perfusion increases detection rates of cerebral ischemia, especially small cortical ischemic lesions, while the detection of lacunar and infratentorial stroke lesions remains limited. Perfusion CT enables estimation of collateral flow in acute occlusion of large intra- or extracranial arteries. Currently, no established reliable thresholds are available for determining infarct core and penumbral tissue by CT perfusion. Moreover, perfusion parameters depend on the processing algorithms and the software used for calculation. However, a number of studies point towards a reduction of cerebral blood volume (CBV) below 2 ml/100 g as a critical threshold that identifies infarct core. Large CBV lesions are associated with poor outcome even in the context of recanalization. The extent of early ischemic signs on non-enhanced CT remains the main parameter from CT imaging to guide acute reperfusion treatment. Nevertheless, perfusion CT increases diagnostic and therapeutic certainty in the acute setting. Similar to stroke MRI, perfusion CT enables the identification of tissue at risk of infarction by the mismatch between infarct core and the larger area of critical hypoperfusion. Further insights into the validity of perfusion parameters are expected from ongoing trials of mechanical thrombectomy in stroke.

  14. Perfusion measurement in acute pancreatitis using dynamic perfusion MDCT.

    Science.gov (United States)

    Bize, Pierre E; Platon, Alexandra; Becker, Christoph D; Poletti, Pierre-Alexandre

    2006-01-01

    Our objective was to determine whether MDCT with perfusion imaging could help in assessing the severity of acute pancreatitis in the initial phase of the disease. One hundred six patients with abdominal pain were prospectively enrolled in this study. Patients were separated into two groups: P1 (severe) and P2 (mild) acute pancreatitis. Mean perfusion value was 24.8 mL/100 mL/min in the P1 group and 50.5 mL/100 mL/min in the P2 group (p = 0.0016, significant). Our preliminary data suggest that pancreatic perfusion measurement using MDCT with perfusion imaging could help in assessing the severity of acute pancreatitis.

  15. Perfusion defects in pulmonary perfusion iodine maps: causes and semiology.

    Science.gov (United States)

    Bustos Fiore, A; González Vázquez, M; Trinidad López, C; Mera Fernández, D; Costas Álvarez, M

    2017-12-14

    to describe the usefulness of dual-energy CT for obtaining pulmonary perfusion maps to provide morphological and functional information in patients with pulmonary embolisms. To review the semiology of perfusion defects due to pulmonary embolism so they can be differentiated from perfusion defects due to other causes: alterations outside the range used in the iodine map caused by other diseases of the lung parenchyma or artifacts. CT angiography of the pulmonary arteries is the technique of choice for the diagnosis of pulmonary embolisms. New dual-energy CT scanners are useful for detecting perfusion defects secondary to complete or partial obstruction of pulmonary arteries and is most useful for detecting pulmonary embolisms in subsegmental branches. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Bevacizumab treatment in malignant meningioma with additional radiation necrosis. An MRI diffusion and perfusion case study

    Energy Technology Data Exchange (ETDEWEB)

    Bostroem, J.P. [University of Bonn Medical Center, Department of Neurosurgery, Bonn (Germany); MediClin Robert Janker Clinic and MVZ MediClin, Department of Radiosurgery and Stereotactic Radiotherapy, Bonn (Germany); Seifert, M.; Greschus, S. [University of Bonn Medical Center, Department of Radiology, Bonn (Germany); Schaefer, N.; Herrlinger, U. [University of Bonn Medical Center, Division of Clinical Neurooncology, Department of Neurology, Bonn (Germany); Glas, M. [University of Bonn Medical Center, Division of Clinical Neurooncology, Department of Neurology, Bonn (Germany); University of Bonn Medical Center, Stem Cell Pathologies, Institute of Reconstructive Neurobiology, Bonn (Germany); MediClin Robert Janker Clinic, Clinical Cooperation Unit Neurooncology, Bonn (Germany); Lammering, G. [MediClin Robert Janker Clinic and MVZ MediClin, Department of Radiosurgery and Stereotactic Radiotherapy, Bonn (Germany); MediClin Robert Janker Clinic, Clinical Cooperation Unit Neurooncology, Bonn (Germany); Heinrich-Heine-University of Duesseldorf, Department of Radiotherapy and Radiation Oncology, Duesseldorf (Germany)

    2014-04-15

    Recently two retrospective cohort studies report efficacy of bevacizumab in patients with recurrent atypical and anaplastic meningioma. Another successful therapeutic option of bevacizumab seems to be treatment of cerebral radiation necrosis. However, the antiangiogenic effects in MRI diffusion and perfusion in meningiomas have not been previously described in detail. The objective of this research was to evaluate the clinical and MR imaging effects of bevacizumab in a malignant meningioma patient harboring additional cerebral radiation necrosis. We report the case of an 80-year-old woman who underwent bevacizumab therapy (5 mg/kg every 2 weeks for 2 months) for treatment of a symptomatic radiation necrosis in malignant meningiomatosis of World Health Organization (WHO) grade III. The patient was closely monitored with MRI including diffusion and perfusion studies. Upon bevacizumab therapy, the clinical situation was well stabilized over a period of 4 months until the patient unfortunately died due to pneumonia/septicemia probably unrelated to bevacizumab therapy. Consecutive MRI demonstrated 4 important aspects: (1) considerable decrease of the contrast medium (CM)-enhanced radiation necrosis, (2) mixed response with respect to the meningiomatosis with stable and predominantly growing tumor lesions, (3) a new diffusion-weighted imaging (DWI) lesion in a CM-enhanced tumor as described in gliomas, which we did not interpret as a response to bevacizumab therapy, and (4) new thrombembolic infarcts, which are a known side-effect of bevacizumab treatment. Bevacizumab is effective in the treatment of radiation necrosis. We could not confirm the potential antitumor effect of bevacizumab in this patient. However, we could describe several new radiographic effects of bevacizumab therapy in malignant meningioma. (orig.) [German] In zwei aktuellen retrospektiven Kohortenstudien konnte eine Wirksamkeit von Bevacizumab bei Patienten mit rezidivierenden atypischen und

  17. Quantitative lung perfusion evaluation using Fourier decomposition perfusion MRI.

    Science.gov (United States)

    Kjørstad, Åsmund; Corteville, Dominique M R; Fischer, Andre; Henzler, Thomas; Schmid-Bindert, Gerald; Zöllner, Frank G; Schad, Lothar R

    2014-08-01

    To quantitatively evaluate lung perfusion using Fourier decomposition perfusion MRI. The Fourier decomposition (FD) method is a noninvasive method for assessing ventilation- and perfusion-related information in the lungs, where the perfusion maps in particular have shown promise for clinical use. However, the perfusion maps are nonquantitative and dimensionless, making follow-ups and direct comparisons between patients difficult. We present an approach to obtain physically meaningful and quantifiable perfusion maps using the FD method. The standard FD perfusion images are quantified by comparing the partially blood-filled pixels in the lung parenchyma with the fully blood-filled pixels in the aorta. The percentage of blood in a pixel is then combined with the temporal information, yielding quantitative blood flow values. The values of 10 healthy volunteers are compared with SEEPAGE measurements which have shown high consistency with dynamic contrast enhanced-MRI. All pulmonary blood flow (PBF) values are within the expected range. The two methods are in good agreement (mean difference = 0.2 mL/min/100 mL, mean absolute difference = 11 mL/min/100 mL, mean PBF-FD = 150 mL/min/100 mL, mean PBF-SEEPAGE = 151 mL/min/100 mL). The Bland-Altman plot shows a good spread of values, indicating no systematic bias between the methods. Quantitative lung perfusion can be obtained using the Fourier Decomposition method combined with a small amount of postprocessing. Copyright © 2013 Wiley Periodicals, Inc.

  18. Multi-detector CT perfusion

    Directory of Open Access Journals (Sweden)

    Ashraf M. Enite

    2016-09-01

    Conclusion: CTP is a promising non-invasive technique assessing the efficacy, predicting early response to local treatment therapies and monitoring tumor recurrence. It assesses the degree of post therapy tumor perfusion especially the degree of arterialization.

  19. Analytische Betrachtung des Quantisierungsfehlers bei grundlegenden Rechenoperationen der digitalen Signalverarbeitung

    Directory of Open Access Journals (Sweden)

    W. Schlecker

    2005-01-01

    Full Text Available Bei der Realisierung digitaler Schaltungen mit einem ASIC oder FPGA kann die Wortbreite der Berechnungen frei gewählt werden. Um die Fläche bzw. die benötigte Hardware zu minimieren, wird versucht, die Berechnungen mit minimaler Wortbreite zu implementieren. Dabei muss jedoch das Quantisierungsrauschen, das durch das Beschränken der Wortbreite entsteht, berücksichtigt werden. Häufig wird hierzu eine worst-case Abschätzung des Fehlers gemacht oder mit Simulationen die benötigte Wortbreite bestimmt. Der vorliegende Beitrag betrachtet die Auswirkungen der Quantisierung analytisch. Dabei wird von gleichverteilten Eingangssignalen ausgegangen. Es wird das Quantisierungsrauschen in Abhängigkeit von der Eingangs- und Ausgangswortbreite bei der Multiplikation und beim Skalarprodukt betrachtet. Die Untersuchungen wurden für Runden und für Abschneiden analytisch durchgeführt und durch Simulation bestätigt.

  20. Wirksamkeit von Bitumenemulsionen bei der Wiederverwertung pechhaltiger Materialien im Straßenbau

    OpenAIRE

    Metz, Georg

    2009-01-01

    Die Wirksamkeit von Bitumenemulsionen bei der Wiederverwertung pechhaltiger Straßenausbaustoffe hängt von ihrer Fähigkeit zur Immobilisierung der im Pech enthaltenen PAK und Phenole sowie von ihrer bautechnischen Eignung bei der Verarbeitung eines konkreten Straßenausbaustoffes ab. Die Arbeit befasst sich mit der Untersuchung und modellhaften Beschreibung des Brechverhaltens handelsüblicher Bitumenemulsionen sowie anhand von pechhaltigem Modellmischgut mit deren Fähigkeiten bei der Einkapselu...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-04-15

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

  2. Die Rolle von RANK-Ligand und Osteoprotegerin bei Osteoporose

    Directory of Open Access Journals (Sweden)

    Hofbauer LC

    2004-01-01

    Full Text Available Receptor activator of nuclear factor (NF- κB ligand (RANKL, sein zellulärer Rezeptor RANK und der Decoy-Rezeptor Osteoprotegerin (OPG stellen ein essentielles Zytokinsystem für die Zellbiologie von Osteoklasten dar. Verschiedene Untersuchungen belegen die Bedeutung von Störungen des OPG/RANKL/RANK-Systems bei der Pathogenese metabolischer Knochenerkrankungen. In dieser Arbeit werden die wichtigsten Störungen des OPG/RANKL/RANK-Systems bei verschiedenen Osteoporoseformen dargestellt. Östrogenrezeptor- (ER- Agonisten wie 17 β-Östradiol, Raloxifen und Genistein stimulieren die osteoblastäre Produktion von OPG durch Aktivierung von ER- α in vitro, während Lymphozyten von Patientinnen mit Östrogenmangel RANKL überexprimieren. Die parenterale Gabe von OPG vermag den mit Östrogenmangel assoziierten Knochenverlust im Tiermodell und in einer kleineren klinischen Studie zu verhindern. Glukokortikoide und Immunsuppressiva steigern gleichzeitig die RANKL-Expression und hemmen die OPG-Produktion in osteoblastären Zellen in vitro. Glukokortikoide sind auch in vivo imstande, die OPG-Serumspiegel deutlich zu reduzieren. Dagegen hemmen biomechanische Reize in vitro die RANKL-Produktion und steigern die OPG-Produktion. Ein Fehlen dieser biomechanischen Reize bei längerer Immobilisierung kann daher den RANKL/OPG-Quotienten steigern, während die tierexperimentelle Immobilisierungs-Osteoporose durch die parenterale Gabe von OPG gemildert werden kann.

  3. Rigiscan®-Monitoring der Erektion unter audiovisueller sexueller Stimulation ohne/mit Viagra™ bei Patienten mit erektiler Dysfunktion

    Directory of Open Access Journals (Sweden)

    Perabo FGE

    2000-01-01

    zwischen negativem Pharmakoduplex (keine oder geringe Erektion, ungenügende Perfusion und Mißerfolg der Viagra™-Medikation. Patienten mit einer negativen Pharmako-Testung sprachen in 60 % auf Viagra™ an. Bei positivem Pharmakoduplex ist die Wahrscheinlichkeit groß, daß auch Viagra™ erfolgreich ist. Die RigiScan®-Messung unter visueller Stimulation ohne/mit Viagra™ trägt zur einfachen Differenzierung zwischen organischer und psychogener Erektionsstörung bei. Die aufwendige Diagnostik bei der erektilen Dysfunktion kann deshalb zugunsten des RigiScan®-Monitorings unter audiovisueller Stimulation ohne/mit 50 mg Viagra™ verlassen werden.

  4. UMA PROSPOSTA DEDUTIVISTA PARA PRINCÍPIOS CONTÁBEIS

    Directory of Open Access Journals (Sweden)

    Paulo Schmidt

    2009-09-01

    Full Text Available A proposta deste estudo a apresentar um breve relato sobre a evolução do pensamento cientifico ocorrida na física com a substituição dos princípios contábeis e filosófico, desde a Antiguidade grega ate os dias de hoje, como forma de fundamentar o posicionamento contrario ao raciocínio indutivo para o estabelecimento de uma estrutura conceitual para a contabilidade e para o desenvolvimento dos princípios contábeis. Apos essa incursão pelo campo filosófico, será aduzido um dos trabalhos de D. R. Scott, ex-professor da Universidade de Michigan, que já na década de 1930 defendia o processo de raciocínio dedutivo e a necessidade de coerência e unidade para o estabelecimento dos princípios contábeis. Este estudo justifica-se, principalmente, porque ainda existem pesquisadores da área contábil que defendem o método indutivo com único procedimento cientifico capaz de levar a certeza, Como defendia Descartes. Alem disso, mesmo apos a revolução cientifica princípios teóricos de Newton, pelos princípios da teoria da relatividade de Einstein, alguns pesquisadores defendem a imutabilidade dos princípios contábeis, como sendo verdades indubitáveis, não aceitando o permanente desenvolvimento da teoria contábil e sua continua adaptabilidade a nova realidade ambiental. A contabilidade, assim como toda disciplina do conhecimento humano que postula um patamar cientifico, deve estruturar-se com base em um conjunto de princípios racionalmente dispostos. Diante desse panorama, faz-se mister inquirir se os princípios contábeis podem ser oniscientes e impassíveis as mudanças do mundo?

  5. Pulmonary manifestations in collagen vascular diseases; Pulmonale Manifestationen bei Kollagenosen

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, M.N.A. [Thoraxklinik, Universitaetsklinikum Heidelberg, Abteilung fuer Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Heidelberg (Germany); Universitaetsklinikum Heidelberg, Translational Lung Research Center (TLRC), Heidelberg (Germany); Kreuter, M. [Thoraxklinik, Universitaetsklinikum Heidelberg, Zentrum fuer interstitielle und seltene Lungenerkrankungen, Pneumologie und Beatmungsmedizin, Heidelberg (Germany); Universitaetsklinikum Heidelberg, Translational Lung Research Center (TLRC), Heidelberg (Germany); Kauczor, H.U. [Radiologische Klinik, Universitaetsklinikum Heidelberg, Abteilung fuer Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Universitaetsklinikum Heidelberg, Translational Lung Research Center (TLRC), Heidelberg (Germany); Heussel, C.P. [Thoraxklinik, Universitaetsklinikum Heidelberg, Abteilung fuer Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Heidelberg (Germany); Radiologische Klinik, Universitaetsklinikum Heidelberg, Abteilung fuer Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Universitaetsklinikum Heidelberg, Translational Lung Research Center (TLRC), Heidelberg (Germany)

    2016-10-15

    Pulmonary complications are frequent in patients with collagen vascular diseases (CVD). Frequent causes are a direct manifestation of the underlying disease, side effects of specific medications and lung infections. The standard radiological procedure for the work-up of pulmonary pathologies in patients with CVD is multidetector computed tomography (MDCT) with thin-slice high-resolution reconstruction. The accuracy of thin-slice CT for the identification of particular disease patterns is very high. The pattern of usual interstitial pneumonia (UIP) representing the direct pulmonary manifestation of rheumatoid arthritis (RA) can be identified with a sensitivity of 45 % and a specificity of 96 %. Both direct pulmonary manifestations, drug-induced toxicity and certain infections can have a similar appearance in thin-slice MDCT in various forms of CVD. Knowledge of the patterns and causes contributes to the diagnostic certainty. At first diagnosis of a CVD and associated pulmonary symptoms thin-slice MDCT is recommended. Clinical, lung function and imaging follow-up examinations should be performed every 6-12 months depending on the results of the MDCT. In every case the individual CT morphological patterns of pulmonary involvement must be identified. The combination of information on the anamnesis, clinical and imaging results is a prerequisite for an appropriate disease management. (orig.) [German] Pulmonale Komplikationen sind bei Patienten mit Kollagenosen keine Seltenheit. Haeufig sind eine direkte Manifestation der Grunderkrankung, eine Nebenwirkung der medikamentoesen Therapie oder eine Lungeninfektion die Ursachen. Das radiologische Standardverfahren zur Klaerung pulmonaler Pathologien bei Patienten mit Kollagenosen ist die Multidetektorcomputertomographie mit duennschichtigen Rekonstruktionen (Duennschicht-MDCT). Die Treffsicherheit der Duennschicht-MDCT ist fuer die Identifikation eines Erkrankungsmusters sehr hoch. So kann beispielsweise das Muster einer

  6. New imaging strategies for monitoring molecular pharmacotherapy of GIST; Neue bildgebende Strategien zum Monitoring molekularer Pharmakotherapien bei GIST

    Energy Technology Data Exchange (ETDEWEB)

    Berger, F.; Reiser, M. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen, Institut fuer Klinische Radiologie, Muenchen (Germany)

    2008-09-15

    Erfassung des fruehen und zur Praediktion des laengerfristigen Therapieansprechens auf Imatinib. Die Anwendung der PET ist jedoch aufgrund begrenzter Verfuegbarkeit und der hohen Kosten eingeschraenkt. Modifizierte CT-Kriterien, die sowohl Groesse- als auch Dichteaenderungen beruecksichtigen, sind besonders bei der Evaluation des fruehen Therapieansprechens viel versprechend. Die weitere Optimierung von Responsekriterien sowie Evaluation moeglicher neuer Responsemarker, wie die quantitative Bewertung der Perfusion, koennen vermutlich zu einem verbesserten Monitoring molekularer Pharmakotherapien bei GIST beitragen. (orig.)

  7. Lung perfusion scintigraphy by SPECT

    International Nuclear Information System (INIS)

    Hirayama, Takanobu

    1990-01-01

    The initial study reports the characteristic performance using lung segmental phantom filled in Tc-99m pertechnetate. To evaluate the segmental defect in lung perfusion scintigraphy, we applied Bull's-eye analysis in addition to planar image set. Bull's-eye analysis especially facilitated the interpretation in both middle and lower lobes. Subsequently, to evolute the clinical application of Bull's-eye analysis, pulmonary scintigraphy was performed on 10 normal subjects and 60 patients with several pulmonary diseases. Of interest, Bull's-eye analysis, however, encouraged the interpretation in both lower lobes. To calculate the extention and severity of perfusion defect, the present study describes Bull's-eye analysis. Quantitative scoring showed higher in patients with lung cancer than those with pulmonary tuberculosis. The present study focus that Bull's-eye analysis can be useful for evaluating perfusion in patients with a couple of pulmonary diseases. (author)

  8. Dynamic CT myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncological and Pathological Sciences, University of Rome “Sapienza”, Latina (Italy); Eid, Marwen [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul (Korea, Republic of); Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Mangold, Stefanie [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen (Germany); and others

    2016-10-15

    Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

  9. Dynamic CT myocardial perfusion imaging identifies early perfusion abnormalities in diabetes and hypertension : Insights from a multicenter registry

    NARCIS (Netherlands)

    Vliegenthart, Rozemarijn; De Cecco, Carlo N.; Wichmann, Julian L.; Meinel, Felix G.; Pelgrim, Gert Jan; Tesche, Christian; Ebersberger, Ullrich; Pugliese, Francesca; Bamberg, Fabian; Choe, Yeon Hyeon; Wang, Yining; Schoepf, U. Joseph

    2016-01-01

    Background: To identify patients with early signs of myocardial perfusion reduction, a reference base for perfusion measures is needed. Objective: To analyze perfusion parameters derived from dynamic computed tomography perfusion imaging (CTPI) in patients with suspected coronary artery disease

  10. Placental perfusion - a human alternative

    DEFF Research Database (Denmark)

    Mose, Tina; Knudsen, Lisbeth E

    2006-01-01

    between the mother and foetus. Dual perfusion of a single cotyledon in the human placenta can contribute to a better understanding of the placental barrier, transport rate and mechanisms of different substances and placental metabolism. The perfusion system has recently been established in Copenhagen...... and represents a supplement and alternative to animal testing, bypassing the animal to human extrapolation. Placentas are readily obtainable from most births upon informed consent from the mothers and are considered a promising tissue alternative/supplement to animal experiments. The system is validated...... as a part of work package 2 of the integrated project ReProTect....

  11. Erste Erfahrungen mit der subkutanen Harnableitung bei der palliativen Therapie von Ureterobstruktionen

    Directory of Open Access Journals (Sweden)

    Würnschimmel E

    2003-01-01

    Full Text Available Eine Harnableitung in Form von Nephrostomien oder inneren Schienen ist bei Patienten mit Harnstauungsnieren aufgrund retroperitonealer Malignome nicht selten die einzige palliative Therapiemöglichkeit. Die subkutane Harnableitung mittels einer Prothese aus Silikon-PTFE ist eine neue, minimal-invasive Therapieoption. Wir haben bisher bei 4 Patientinnen diese Behandlung mit ausgezeichneten Ergebnissen angewendet.

  12. "Updates to Model Algorithms & Inputs for the Biogenic Emissions Inventory System (BEIS) Model"

    Science.gov (United States)

    We have developed new canopy emission algorithms and land use data for BEIS. Simulations with BEIS v3.4 and these updates in CMAQ v5.0.2 are compared these changes to the Model of Emissions of Gases and Aerosols from Nature (MEGAN) and evaluated the simulations against observatio...

  13. Automatic assessment of cardiac perfusion MRI

    DEFF Research Database (Denmark)

    Ólafsdóttir, Hildur; Stegmann, Mikkel Bille; Larsson, Henrik B.W.

    2004-01-01

    In this paper, a method based on Active Appearance Models (AAM) is applied for automatic registration of myocardial perfusion MRI. A semi-quantitative perfusion assessment of the registered image sequences is presented. This includes the formation of perfusion maps for three parameters; maximum up...

  14. MRCP in primary sclerosing cholangitis; MRCP bei primaerer sklerosierender Cholangitis

    Energy Technology Data Exchange (ETDEWEB)

    Weber, C.; Krupski, G.; Lorenzen, J.; Adam, G. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie; Grotelueschen, R.; Rogiers, X. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Abt. fuer Hepatobilaere Chirurgie; Seitz, U. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Klinik fuer Interdisziplinaere Endoskopie

    2003-02-01

    Purpose: Evaluation of MR-cholangiopancreaticography (MRCP) for the diagnosis of primary sclerosing cholangitis (PSC) in correlation with endoscopic retrograde cholangiopancreaticography (ERCP) and in comparison to the diagnostic accuracy of various T2-weighted sequences. Methods and Materials: Fifty-five patients (34 males, 21 females: mean age 40 years, range 16 to 65 years) with suspected PSC were examined in a 1.5 T MR unit (Magnetom Vision, Siemens, Erlangen), using breath-hold transverse and coronal HASTE, paracoronal RARE and thin-sliced HASTE (TS-HASTE) sequences. Applying a five-point-scale, two blinded investigators assessed the image quality for ROC analysis. Morphologic criteria of PSC were documented and correlated with ERCP, which served as the gold standard, and sensitivity, specificity and diagnostic accuracy were calculated. Results: PSC was confirmed in 40 of 55 patients (ERCP 55 of 55, liver biopsy 37 of 55), with concomitant chronic ulcerative colitis in 27 and Crohn's disease in 6 of the 40 patients. Qualitative analysis of the image quality showed no significant difference between RARE, HASTE and thin-sliced HASTE sequences (3.4/3.5/3.2). The RARE sequence had the highest sensitivity (97%), specificity (64%) and accuracy (84%) for the detection of PSC. The difference between HASTE and thin-sliced HASTE was statistically significant (p<0.01). Of the 40 patients with confirmed PSC, 29 were followed by MRI and 3 underwent a liver transplantation within the follow-up period. A Klatskin tumor, which was misdiagnosed by MRCP, was diagnosed by brush biopsy in 1 of the 40 patients. Interobserver variability was adequate to good (kappa 0.4 to 0.7), depending on the chosen sequence. (orig.) [German] Ziel: Wertigkeit der MRCP bei der Diagnostik der primaeren sklerosierenden Cholangitis (PSC) in Korrelation zur endoskopischen retrograden Cholangiopankreatikographie (ERCP) und Vergleich der diagnostischen Treffsicherheit verschiedener T{sub 2

  15. 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.)

  16. Shoulder injuries in overhead sports; Schultergelenkverletzungen bei Ueberkopfsportarten

    Energy Technology Data Exchange (ETDEWEB)

    Woertler, K. [Technische Universitaet Muenchen (Germany). Institut fuer Roentgendiagnostik

    2010-05-15

    Overhead sport places great demands on the shoulder joint. Shoulder pain in overhead athletes and throwers can in the majority of cases be attributed to lesions resulting from chronic overuse of tendons and capsuloligamentous structures or to sequels of microinstability and secondary impingement. Due to its great impact on therapeutic decisions, imaging in athletes with unclear shoulder pain is a challenge. In this connection, magnetic resonance (MR) arthrography represents the cross-sectional imaging modality of first choice, as it allows depiction and exclusion of pathologic alterations of all relevant joint structures with sufficient confidence. This article reviews the biomechanical and clinical aspects and MR arthrographic features of the most common shoulder pathologies in overhead athletes, including biceps tendinopathy, superior labral anterior-posterior (SLAP) lesions, rotator cuff lesions, as well as extrinsic and intrinsic impingement syndromes. (orig.) [German] Ueberkopfsportarten stellen grosse Anforderungen an das Schultergelenk. Schulterbeschwerden bei Ueberkopf- und Wurfsportlern koennen in der Mehrzahl der Faelle auf eine chronische Ueberlastung von Sehnen und Kapsel-Band-Strukturen oder auf die Folgen einer Mikroinstabilitaet und sekundaerer Impingementsyndrome zurueckgefuehrt werden. Wegen ihres grossen Einflusses auf die Therapieentscheidung stellt die Bildgebung bei Athleten mit unklaren Schulterbeschwerden eine Herausforderung dar. Die MR-Arthrographie ist in diesem Zusammenhang als Schnittbildverfahren der ersten Wahl anzusehen, da sie den Nachweis bzw. Ausschluss pathologischer Veraenderungen aller relevanten Gelenkstrukturen mit ausreichender Sicherheit ermoeglicht. Dieser Artikel gibt eine Uebersicht ueber biomechanische und klinische Aspekte sowie MR-arthrographische Befunde der haeufigsten Schultergelenkpathologien bei Ueberkopfsportlern, wie Bizepstendinopathie, Superior-labral-anterior-posterior- (SLAP-)Laesionen, Laesionen der

  17. Diagnostic evaluation of deep vein thrombosis; Diagnostik bei tiefer Venenthrombose

    Energy Technology Data Exchange (ETDEWEB)

    Fuerst, G.; Saleh, A. [Universitaetsklinikum Duesseldorf (Germany). Inst. fuer Diagnostische Radiologie

    2001-12-01

    CT and MRI are efficient modalities for the imaging of venous thrombi. Their application currently is restricted to complementary use, in cases when results of US and/or phlebography leave open questions (as e.g. central extension of thrombi, assessment of causes, post-surgery follow-up). (orig./CB) [German] CT und MRT sind effiziente Techniken zur Venendarstellung bei Thrombose. Ihr Einsatz ist derzeit Fragestellungen vorbehalten, die sich sonographisch und/oder phlebographisch nicht ausreichend klaeren lassen (z. B. Thromboseausdehnung nach zentral, Ursachenabklaerung, postoperative Kontrollen). (orig.)

  18. [IV drug perfusions: safety principles].

    Science.gov (United States)

    Lelieur, Florence; Cabelguenne, Delphine; Marcel, Marie; Favier, Claudine; Piriou, Vincent

    2017-05-01

    An intravenous perfusion is a procedure which comprises infection and medication risks. To manage these risks, caregivers must respect, in addition to the usual hygiene rules, a series of best practices, ensuring the proper use and management of the medical devices and administered drugs. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. Pulmonary ventilation/perfusion scan

    Science.gov (United States)

    ... to stop eating (fast), be on a special diet, or take any medicines before the test. A chest x-ray is usually done before or after a ventilation and perfusion scan. You wear a hospital gown or comfortable clothing that does not have ...

  20. 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

  1. Contralateral thalamic hypoperfusion on brain perfusion SPECT

    International Nuclear Information System (INIS)

    Lee, Seok Mo; Bae, Sang Kyun; Yoo, Kyung Moo; Yum, Ha Yong

    2000-01-01

    Brain perfusion single photon emission computed tomography (SPECT) is useful for the localization of cerebrovascular lesion and sometimes reveals more definite lesion than radiologic imaging modality such as CT or MRI does. The purpose of this study was to evaluate the diagnostic usefulness of brain perfusion SPECT in patients with hemisensory impairment. Thirteen consecutive patients (M:F= 8:5, mean age = 48) who has hemisensory impairment were included. Brain perfusion SPECT was performed after intravenous injection of 1110 MBq of Tc-99m ECD. The images were obtained using a dual-head gamma camera with ultra-high resolution collimator. Semiquantitative analysis was performed after placing multiple ROIs on cerebral cortex, basal ganglia, thalamus and cerebellum. There were 10 patients with left hemisensory impairment and 3 patients with right-sided symptom. Only 2 patients revealed abnormal signal change in the thalamus on MRI. But brain perfusion SPECT showed decreased perfusion in the thalamus in 9 patients. Six patients among 10 patients with left hemisensory impairment revealed decreased perfusion in the contralateral thalamus on brain SPECT. The other 4 patients revealed no abnormality. Two patients among 3 patients with right hemisensory impairment also showed decreased perfusion in the contralateral thalamus on brain SPECT. One patients with right hemisensory impairment showed ipsilateral perfusion decrease. Two patients who had follow-up brain perfusion SEPCT after treatment revealed normalization of perfusion in the thalamus. Brain perfusion SPECT might be a useful tool in diagnosing patients with hemisensory impairment

  2. Magnetic resonance perfusion imaging without contrast media

    International Nuclear Information System (INIS)

    Martirosian, Petros; Graf, Hansjoerg; Schick, Fritz; Boss, Andreas; Schraml, Christina; Schwenzer, Nina F.; Claussen, Claus D.

    2010-01-01

    Principles of magnetic resonance imaging techniques providing perfusion-related contrast weighting without administration of contrast media are reported and analysed systematically. Especially common approaches to arterial spin labelling (ASL) perfusion imaging allowing quantitative assessment of specific perfusion rates are described in detail. The potential of ASL for perfusion imaging was tested in several types of tissue. After a systematic comparison of technical aspects of continuous and pulsed ASL techniques the standard kinetic model and tissue properties of influence to quantitative measurements of perfusion are reported. For the applications demonstrated in this paper a flow-sensitive alternating inversion recovery (FAIR) ASL perfusion preparation approach followed by true fast imaging with steady precession (true FISP) data recording was developed and implemented on whole-body scanners operating at 0.2, 1.5 and 3 T for quantitative perfusion measurement in various types of tissue. ASL imaging provides a non-invasive tool for assessment of tissue perfusion rates in vivo. Images recorded from kidney, lung, brain, salivary gland and thyroid gland provide a spatial resolution of a few millimetres and sufficient signal to noise ratio in perfusion maps after 2-5 min of examination time. Newly developed ASL techniques provide especially high image quality and quantitative perfusion maps in tissues with relatively high perfusion rates (as also present in many tumours). Averaging of acquisitions and image subtraction procedures are mandatory, leading to the necessity of synchronization of data recording to breathing in abdominal and thoracic organs. (orig.)

  3. Taxonomia de distorções contábeis

    Directory of Open Access Journals (Sweden)

    José Humberto da Cruz Cunha

    2017-05-01

    Full Text Available http://dx.doi.org/10.5007/1518-2924.2017v22n49p127 Discute o uso de uma taxonomia de distorções contábeis provenientes de erros e fraudes, voltada para o uso dos auditores na análise dos riscos e escolha dos procedimentos de auditoria. Sua elaboração segue as orientações conceituais da classificação facetada, por meio de levantamento conceitual em pesquisa bibliográfica. A taxonomia apresentada possui como categorias fundamentais as fases da informação, aspectos essenciais, afirmações, ciclos de recursos, subciclos de recursos, distorções contábeis e afirmações (objetivos de auditoria. É apresentada a metodologia de elaboração da taxonomia, bem como a sua aplicabilidade na auditoria contábil como instrumento de organização da informação e do conhecimento. Conclui que, a partir dos exemplos utilizados, é possível afirmar que a taxonomia orienta a análise das distorções como uma trilha de auditoria, padronizando os conceitos identificados na linguagem natural em uma estrutura de classificação padronizada.

  4. Die Rolle von Osteoklasten bei der arthritischen Knochenerosion

    Directory of Open Access Journals (Sweden)

    Schett G

    2003-01-01

    Full Text Available Knöcherne Erosionen stellen eine wesentliche Ursache für die funktionelle Einschränkung von Patienten mit rheumatoider Arthritis dar. Bis vor kurzem war über den Pathomechanismus dieser Veränderungen nur wenig bekannt. Dieser Review faßt die letzten Erkenntnisse über die Ausbildung einer Knochenschädigung bei entzündlichen Gelenkerkrankungen zusammen und fokussiert insbesondere die Rolle von Osteoklasten. Es wird ein Überblickzu den Hinweisen für eine Präsenz von Osteoklasten im entzündlich veränderten Gelenk gegeben. Weiters werden die Faktoren diskutiert, die die Osteoklastogenese im Rahmen einer Gelenkentzündung aktivieren können. Hier wird im besonderen auf die Rolle von Receptor-Activator of Nuclear Factor Kappa B Ligand (RANKL eingegangen. Im weiteren werden die Auswirkungen einer Osteoklastenhemmung in den verschiedenen Arthritismodellen zusammengefaßt und Möglichkeiten einer therapeutischen Nutzung bei rheumatoider Arthritis diskutiert.

  5. Bewegungstherapie bei Adipositas und Fettstoffwechselstörungen

    Directory of Open Access Journals (Sweden)

    Haber P

    2014-01-01

    Full Text Available Die physiologische Ursache der Adipositas ist eine langfristig positive Energiebilanz. Eine Verringerung des durchschnittlichen Energieumsatzes im Berufsalltag ohne Kompensation in der Freizeit und eine geringe Zunahme der durchschnittlichen täglichen Energieaufnahme in den vergangenen Jahrzehnten sind die Grundlage der modernen Adipositasepidemie. Die physiologische Voraussetzung zum Abbau von Körperfett ist eine langfristig negative Energiebilanz. Zusätzliche körperliche Bewegung, sowohl als Alltagsbewegung als auch als sportliches Training, ohne Kompensation durch vermehrte Nahrungsaufnahme, macht dies möglich. Dies führt zu einem Abbau von Körperfett, bis sich eine neue Energiehomöostase bei geringerem Gewicht und Körperfett einstellt. Für eine bleibende Wirkung ist es allerdings erforderlich, dass das Bewegungsprogramm im Prinzip lebenslänglich beibehalten wird, da sich bei Verminderung der Bewegungsenergie wieder eine positive Energiebilanz einstellt. Die Wirkung von aerobem Ausdauertraining auf die Blutlipide ist bescheiden. Die Hauptwirkung besteht in einer Änderung der Zusammensetzung des LDL-Cholesterins (Abnahme der „Small-dense“-LDL-Partikel und einer Zunahme der HDL2-Subfraktion. Speziell die Wirkung auf die Lipide wird bereits mit Bewegung mit geringer Intensität (Gehen erreicht. Die Fitness (V°O2max hat keinen zusätzlichen Einfluss. Eine deutlich stärkere Wirkung auf die Lipide als Ausdauertraining scheint ein Muskelaufbautraining mit Vermehrung von Muskelmasse zu haben.

  6. Temporal changes in tumor oxygenation and perfusion upon normo- and hyperbaric inspiratory hyperoxia

    Energy Technology Data Exchange (ETDEWEB)

    Thews, Oliver [University of Halle, Institute of Physiology, Halle (Saale) (Germany); Vaupel, Peter [University Medical Center Mainz, Department of Radiooncology and Radiotherapy, Tumor Pathophysiology Section, Mainz (Germany)

    2016-03-15

    Inspiratory hyperoxia under hyperbaric conditions has been shown to effectively reduce tumor hypoxia and to improve radiosensitivity. However, applying irradiation (RT) under hyperbaric conditions is technically difficult in the clinical setting since RT after decompression may be effective only if tumor pO{sub 2} remains elevated for a certain period of time. The aim of the present study was to analyze the time course of tumor oxygenation and perfusion during and after hyperbaric hyperoxia. Tumor oxygenation, red blood cell (RBC) flux for perfusion monitoring, and vascular resistance were assessed continuously in experimental rat DS-sarcomas by polarographic catheter electrodes and laser Doppler flowmetry at 1 and 2 atm (bar) of environmental pressure during breathing of pure O{sub 2} or carbogen (95 % O{sub 2} + 5 % CO{sub 2}). During room air breathing, the tumor pO{sub 2} followed very rapidly within a few minutes the change of the ambient pressure during compression or decompression. With O{sub 2} breathing under hyperbaric conditions, the tumor pO{sub 2} increased more than expected based on the rise of the environmental pressure, although the time course was comparably rapid. Breathing carbogen, the tumor pO{sub 2} followed with a slight delay of the pressure change, and within 10 min after decompression the baseline values were reached again. RBC flux increased during carbogen breathing but remained almost constant with pure O{sub 2}, indicating a vasodilation (decrease in vascular resistance) with carbogen but a vasoconstriction (increase in vascular resistance) with O{sub 2} during hyperbaric conditions. Since the tumor pO{sub 2} directly followed the environmental pressure, teletherapy after hyperbaric conditions does not seem to be promising as the pO{sub 2} reaches baseline values again within 5-10 min after decompression. (orig.) [German] Inspiratorische Hyperoxie unter hyperbaren Bedingungen reduziert sehr effektiv die Tumorhypoxie und erhoeht die

  7. Myocardial perfusion modeling using MRI

    DEFF Research Database (Denmark)

    Larsson, H B; Fritz-Hansen, T; Rostrup, Egill

    1996-01-01

    In the present study, it is shown that it is possible to quantify myocardial perfusion using magnetic resonance imaging in combination with gadolinium diethylenetriaminopentaacetic acid (Gd-DTPA). Previously, a simple model and method for measuring myocardial perfusion using an inversion recovery...... of Gd-DTPA (lambda), the vascular blood volume (Vb), and the time delay through the coronary arteries (delta T). The model was evaluated by computer simulation and used on experimental results from seven healthy subjects. The results in the healthy volunteers for a region of interest placed...... in the anterior myocardial wall were (mean +/- SD) Ki = 54 +/- 10 ml/100 g/min, lambda = 30 +/- 3 ml/100 g, Vb = 9 +/- 2 ml/100 g, delta T = 3.2 +/- 1.1 s. These results are in good agreement with similar results obtained by other methods....

  8. Die hyperbare Oxygenierung als ultima ratio bei schwerwiegenden Wundheilungsstörungen nach Salvage-Laryngektomie

    OpenAIRE

    Ahmad, Z; Lorenz, KJ; Tisch, M

    2017-01-01

    Die Salvage-LE nach primärer RCT bei Larynx-Tumoren ist mit einer hohen Komplikationsrate hinsichtlich pharyngokutaner Fisteln und Wundheilungsstörungen assoziiert. Mittels gestielter Lappenplastiken kann diese Situation verbessert werden. Wir berichten über einen Patienten, bei dem nach primärer RCT eines cT3 cn2c M0 G3 Larynx-CA's bei Rezidivsituation eine Salvage-LE notwendig wurde. Intraoperativ wurde der Neopharynx zudem mit einem M. pectoralis-Lappen gedeckt. Nach zunächst unauffälligem...

  9. Quantitative perfusion imaging in magnetic resonance imaging; Quantitative Perfusionsbildgebung in der Magnetresonanztomographie

    Energy Technology Data Exchange (ETDEWEB)

    Zoellner, F.G.; Gaa, T.; Zimmer, F. [Universitaet Heidelberg, Computerunterstuetzte Klinische Medizin, Medizinische Fakultaet Mannheim, Mannheim (Germany); Ong, M.M.; Riffel, P.; Hausmann, D.; Schoenberg, S.O.; Weis, M. [Universitaet Heidelberg, Institut fuer Klinische Radiologie und Nuklearmedizin, Universitaetsmedizin Mannheim, Medizinische Fakultaet Mannheim, Mannheim (Germany)

    2016-02-15

    Magnetic resonance imaging (MRI) is recognized for its superior tissue contrast while being non-invasive and free of ionizing radiation. Due to the development of new scanner hardware and fast imaging techniques during the last decades, access to tissue and organ functions became possible. One of these functional imaging techniques is perfusion imaging with which tissue perfusion and capillary permeability can be determined from dynamic imaging data. Perfusion imaging by MRI can be performed by two approaches, arterial spin labeling (ASL) and dynamic contrast-enhanced (DCE) MRI. While the first method uses magnetically labelled water protons in arterial blood as an endogenous tracer, the latter involves the injection of a contrast agent, usually gadolinium (Gd), as a tracer for calculating hemodynamic parameters. Studies have demonstrated the potential of perfusion MRI for diagnostics and also for therapy monitoring. The utilization and application of perfusion MRI are still restricted to specialized centers, such as university hospitals. A broad application of the technique has not yet been implemented. The MRI perfusion technique is a valuable tool that might come broadly available after implementation of standards on European and international levels. Such efforts are being promoted by the respective professional bodies. (orig.) [German] Die Magnetresonanztomographie (MRT) zeichnet sich durch einen ueberlegenen Gewebekontrast aus, waehrend sie nichtinvasiv und frei von ionisierender Strahlung ist. Sie bietet Zugang zu Gewebe- und Organfunktion. Eine dieser funktionellen bildgebenden Verfahren ist die Perfusionsbildgebung. Mit dieser Technik koennen u. a. Gewebeperfusion und Kapillarpermeabilitaet aus dynamischen Bilddaten bestimmt werden. Perfusionsbildgebung mithilfe der MRT kann durch 2 Ansaetze, naemlich ''arterial spin labeling'' (ASL) und dynamische kontrastverstaerkte (DCE-)MRT durchgefuehrt werden. Waehrend die erste Methode magnetisch

  10. Dosimetry in myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Toledo, Janine M.; Trindade, Bruno; Ribeiro, Tarcisio P.C.

    2011-01-01

    This paper conducts a dosimetric investigation on the myocardial perfusion image protocol, together with a literature reviewing, motivated by the significant statistic increasing on mortality, morbidity and disability associated with cardiovascular disease, surpassing infectious diseases. Nuclear Cardiology plays a role n the diagnostic functional evaluation of the heart and in the prognostic of patients with suspected or known cardiac ischemia. In the context of unstable myocardial ischemic syndrome, myocardial perfusion scintigraphy is a non-invasive procedure performed by administering a radiopharmaceutical targeted to the heart. As tool for this study are that the images obtained by thoracic angiotomography and abdominal aorta as a anatomic and functional information for model reproduction in SISCODES - System of Codes for Absorbed Dose Calculations based on Stochastic Methods. Data were manipulated in order to create a voxel computational model of the heart to be running in MCNP - Monte Carlo Neutron Particle Code. . It was assumed a homogeneous distribution of Tl-201 in cardiac muscle. Simulations of the transport of particles through the voxel and the interaction with the heart tissue were performed. As a result, the isodose curves in the heart model are displayed as well as the dose versus volume histogram of the heart muscle. We conclude that the present computational tools can generate doses distributed in myocardial perfusion. (author)

  11. Dosimetry in myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Toledo, Janine M.; Trindade, Bruno; Ribeiro, Tarcisio P.C. [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte (Brazil). Dept. de Engenharia Nuclear. Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares

    2011-07-01

    This paper conducts a dosimetric investigation on the myocardial perfusion image protocol, together with a literature reviewing, motivated by the significant statistic increasing on mortality, morbidity and disability associated with cardiovascular disease, surpassing infectious diseases. Nuclear Cardiology plays a role n the diagnostic functional evaluation of the heart and in the prognostic of patients with suspected or known cardiac ischemia. In the context of unstable myocardial ischemic syndrome, myocardial perfusion scintigraphy is a non-invasive procedure performed by administering a radiopharmaceutical targeted to the heart. As tool for this study are that the images obtained by thoracic angiotomography and abdominal aorta as a anatomic and functional information for model reproduction in SISCODES - System of Codes for Absorbed Dose Calculations based on Stochastic Methods. Data were manipulated in order to create a voxel computational model of the heart to be running in MCNP - Monte Carlo Neutron Particle Code. . It was assumed a homogeneous distribution of Tl-201 in cardiac muscle. Simulations of the transport of particles through the voxel and the interaction with the heart tissue were performed. As a result, the isodose curves in the heart model are displayed as well as the dose versus volume histogram of the heart muscle. We conclude that the present computational tools can generate doses distributed in myocardial perfusion. (author)

  12. Standardized perfusion value of the esophageal carcinoma and its correlation with quantitative CT perfusion parameter values.

    Science.gov (United States)

    Djuric-Stefanovic, A; Saranovic, Dj; Sobic-Saranovic, D; Masulovic, D; Artiko, V

    2015-03-01

    Standardized perfusion value (SPV) is a universal indicator of tissue perfusion, normalized to the whole-body perfusion, which was proposed to simplify, unify and allow the interchangeability among the perfusion measurements and comparison between the tumor perfusion and metabolism. The aims of our study were to assess the standardized perfusion value (SPV) of the esophageal carcinoma, and its correlation with quantitative CT perfusion measurements: blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface area product (PS) of the same tumor volume samples, which were obtained by deconvolution-based CT perfusion analysis. Forty CT perfusion studies of the esophageal cancer were analyzed, using the commercial deconvolution-based CT perfusion software (Perfusion 3.0, GE Healthcare). The SPV of the esophageal tumor and neighboring skeletal muscle were correlated with the corresponding mean tumor and muscle quantitative CT perfusion parameter values, using Spearman's rank correlation coefficient (rS). Median SPV of the esophageal carcinoma (7.1; range: 2.8-13.4) significantly differed from the SPV of the skeletal muscle (median: 1.0; range: 0.4-2.4), (Z=-5.511, pCT perfusion measurements and statistically significant correlation was proved. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Konservative und operative Therapie bei Harninkontinenz, Deszensus und Urogenitalbschwerden

    Directory of Open Access Journals (Sweden)

    Eberhard J

    2000-01-01

    Full Text Available Urogynäkologische Beschwerden wie Harninkontinenz, Infektionen, vulvo-vaginale und vesikale Reizzustände, Juckreiz, Dyspareunie, Beckenbodenschwäche, Deszensusbeschwerden werden in irgendeiner Form bei fast jeder Frau im Laufe ihres Lebens zur behandlungsbedürftigen Krankheit. Die Ursachen dieser häufigsten Frauenleiden sind vielfältig. Eine erfolgreiche Therapie sollte auf der Polyätiologie urogynäkologischer Krankheiten aufbauen und die verschiedenen Therapiemöglichkeiten zu einem patienten- und krankheitsadaptierten Behandlungskonzept zusammenfügen. Die Bausteine der konservativen Therapie sind: Trink- und Miktionstraining, Physiotherapie mit den Hilfsmitteln Kugeln, Kegel, Elektrostimulation und Biofeedbackmethoden; Östrogene, Pessare, Infekttherapie, Intimpflege, blasenrelaxierende und andere urogynäkologische Medikamente. Der Einsatz dieser Therapiebausteine wird ausführlich besprochen. Auch wird gezeigt, wann und wie operiert werden soll, wenn die konservative Therapie nicht zum Ziel führt.

  14. Cryotherapy in rheumatic disorders; Kryotherapie bei rheumatischen Erkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, H. [Rheumaklinik Immanuel-Krankenhaus, Berlin (Germany). Innere Rheumatologische Abt.

    1994-12-31

    When applied locally, cold therapy (cryotherapy) has the effect of inhibiting inflammation, occluding blood vessels, and stopping bleeding. Active rheumatic inflammation, activated arthrosis, and swelling after injury can be alleviated by local cold application, while heat application would worsen the situation. In whole-body cryotherapy the whole patient, wearing only a bathing suit, is exposed to a temperature of -100 C. The present paper descrcribes the cold room of the Immanuel Hospital in Berlin-Wannsee. (BWI) [Deutsch] Kaeltetherapie (Kryotherapie) wirkt lokal angewendet entzuendungshemmend, blutgefaessabdichtend und blutstillend. Eine aktive rheumatische Entzuendung, aktivierte Arthrose und Schwellungsreaktionen bei Verletzungen werden durch lokale Kaelteanwendungen gedaempft, wogegen Waerme den akuten Zustand verschlimmern wuerde. In der Ganzkoerperkaeltetherapie wird der ganze Mensch in Badebekleidung einer realen Temperatur von -100 C ausgesetzt. Der vorliegende Beitrag beschreibt die Kaeltekammer des Immanuel Krankenhauses in Berlin Wannsee. (BWI)

  15. Suche nach Charginos in 4 Jet Ereignissen bei LEP2

    CERN Document Server

    AUTHOR|(CDS)2086503

    1997-01-01

    Zum heutigen Tag sind der Hochenergiephysik einige Hundert Teilchen und Teilchenzustände bekannt, die dem Anschein nach auf sehr komplexe Weise wechselwirken und so die beobachtbare Welt konstituieren. Bei näherer Betrachtung sind jedoch nur wenige Teilchen und Wechselwirkungen elementar, in dem Sinne, dass die übrigen sich als aus ihnen zusammengesetzt ansehen lassen. Die Frage, wie man diese elementaren Teilchen und ihre fundamentalen Wechselwirkungen systematisch beschreiben kann, beantwortet das Standardmodell der Elementarteilchenphysik. Es verwendet das Spektrum der fundamentalen Materie, die inneren Symmetrieeigenschaften dieses Spektrums und das Eichprinzip, um eine Beschreibung im Rahmen der Quantenfeldtheorie zu formalisieren. Das Standardmodell leistet so eine prinzipielle Beschreibung der bis heute betrachteten Hochenergiephysik. Dabei treten allerdings einige Probleme auf, die es attraktiv erscheinen lassen, das Standardmodell um eine weitere Symmetrieeigenschaft zu erweitern, nämlich um die ...

  16. Cyber-Physical Systems - Wissenschaftliche Herausforderungen Bei Der Entwicklung

    Science.gov (United States)

    Broy, Manfred

    Cyber-Physical Systems adressieren die enge Verbindung eingebetteter Systeme zur Überwachung und Steuerung physikalischer Vorgänge mittels Sensoren und Aktuatoren über Kommunikationseinrichtungen mit den globalen digitalen Netzen (dem Cyberspace"). Dieser Typus von Systemen ermöglicht über Wirkketten eine Verbindung zwischen Vorgängen der physischen Realität und den heute verfügbaren digitalen Netzinfrastrukturen. Dies erlaubt vielfältige Applikationen mit hohem wirtschaftlichen Potential, und mit starker Innovationskraft. Die vollständige Ausschöpfung des Potentials erfordert aber gezielte wissenschaftliche Anstrengungen bei der Entwicklung solcher Systeme im Hinblick auf Methodik, Technologie, Kostenbeherrschung und funktionale Angemessenheit.

  17. Berechnung verkehrlicher Substitutionseffekte im Personenverkehr bei Online-Shopping

    Science.gov (United States)

    Nerlich, Mark R.; Schiffner, Felix; Vogt, Walter; Rauh, Jürgen; Breidenbach, Petra

    Für Güter des täglichen, mittelfristigen und langfristigen Bedarfs sowie für das Beispiel Baumarktartikel wird das Potenzial für Personenverkehrsaufwand von Einkaufsaktivtäten quantitativ abgeschätzt. Die entwickelten Algorithmen behandeln die einkaufsvorbereitende Information und den eigentlichen Einkauf, d.h. den Erwerb eines Gutes, separat. Informationsaktivitäten haben insbesondere bei höherwertigen Gütern einen hohen Stellenwert und damit auch verkehrliche Relevanz. Wie Berechnungen zeigen, spart Online-Shopping Informations- und Einkaufsverkehrsaufwand im Pkw-Verkehr ein. Die notwendigen Eingangsdaten wie differenzierte Informations- und Einkaufshäufigkeiten sowie verkehrliche Parameter zu Verkehrsmittelwahl, Entfernungen und Wegekopplungen wurden aus eigenen Erhebungen gewonnen.

  18. 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.)

  19. Pathophysiologie des Kollagenstoffwechsels bei Patienten mit Induratio penis plastica (IPP

    Directory of Open Access Journals (Sweden)

    Lahme S

    2000-01-01

    Full Text Available Die Pathogenese der IPP ist bis heute nicht geklärt. Histopathologische Untersuchungen zeigen, daß der Kollagenstoffwechsel eine Rolle spielt. Dies veranlaßte uns zur genauen Analyse der Kollagenstoffwechselparameter bei IPP. Bei 11 Patienten mit IPP und 11 Kontrollpersonen wurden Kollagenstoffwechselparameter (Prokollagen III [PIIIP], PMN-Elastase [PMN-E], Fibronektin [FN], Fibronektinrezeptor [FN-R] und alpha1-Proteinase-Inhibitor [alpha1-PI] im cavernösen und peripheren Blut bestimmt. PMN-E, PIIIP, FN und FN-R waren in den beiden Untersuchungsgruppen nicht unterschiedlich. Die peripher venösen unterschieden sich nicht von den cavernösen Blutproben. Sowohl im peripher venös (158,55 mg/dl als auch im cavernös entnommenen Blut (168,29 mg/dl war die Konzentration des a1-PI signifikant niedriger als in der Kontrollgruppe (214,82 mg/dl. An einem zweiten Kollektiv von 23 Patienten wurden Analysen des Phänotyps für alpha1-PI im Hinblick auf das Vorliegen von genetisch determinierten Mangelallelen vorgenommen. Hier zeigte sich kein signifikanter Unterschied zu einem Kontrollkollektiv von 19 gesunden Probanden. Die alpha1-PI Erniedrigung der IPP-Patienten ist signifikant und liegt unterhalb des Normalwertbereichs für die gesunde Population. Ein Mangel an alpha1-PI kann zur Aktivitätserhöhung der Proteasen und zum Umbau des Kollagengewebes führen. Möglicherweise kommt es zusammen mit einem lokal wirksamen Einflußfaktor schließlich zur dystrophen Kalzifikation. Die humangenetischen Untersuchungen sprechen nicht für eine genetische Determinierung des alpha1-PI-Mangels, sondern legen eine erworbene hepatische Störung nahe.

  20. Therapeutische Überlegungen bei sensomotorischer diabetischer Neuropathie

    Directory of Open Access Journals (Sweden)

    Bührlen M

    2013-01-01

    Full Text Available Der Begriff der sensomotorischen diabetischen Neuropathie beschreibt einen heterogenen Beschwerdekomplex, der auf einer diabetesbedingten Schädigung des peripheren Nervensystems beruht. Bis zu 50 % der Menschen mit Diabetes mellitus leiden im Verlauf ihrer Erkrankung an Symptomen einer sensomotorischen Neuropathie. Chronische Schmerzen, Dysund Parästhesien sowie die Komplikation des diabetischen Fußsyndroms stellen für die Betroffenen gravierende Folgen dar. Die Optimierung der metabolischen Kontrolle stellt eine wichtige Basismaßnahme dar. Andere, zweifelsfrei gesicherte Möglichkeiten der Prävention oder kausalen Therapie sind nicht bekannt. Bei Auftreten einer schmerzhaften Neuropathie sollte eine gezielte analgetische Therapie möglichst früh begonnen werden. Mit den trizyklischen Antidepressiva, Duloxetin, Gabapentin und Pregabalin stehen Wirkstoffe zur Verfügung, die eine spezifische Therapie neuropathischer Schmerzen ermöglichen. Dabei ist zu beachten, dass in der Regel keine Schmerzfreiheit erreicht werden kann. Entscheidend ist das Erreichen eines für den Patienten tolerablen Schmerzniveaus unter Minimierung medikamentenassoziierter Nebenwirkungen. Das individuelle Ansprechen auf ein Medikament und die optimale Dosis können nicht vorhergesagt, sondern müssen individuell erprobt werden. Bei leichten Schmerzen können die Nicht-Opioid- Analgetika Paracetamol und Metamizol eingesetzt werden. Fehlen Therapiealternativen, dann stellen Opioide eine weitere Möglichkeit der Therapie starker Schmerzen dar. Aufgrund einer zusätzlichen Monoamin-Wiederaufnahmehemmerwirkung nehmen Tramadol und Tapentadol in dieser Gruppe eine Sonderstellung ein. In der Risiko- Nutzen-Abwägung darf das Nebenwirkungs- und Abhängigkeitspotenzial der Opioide in der Langzeittherapie nicht unterschätzt werden. Für andere medikamentöse Therapien oder alternative Therapiemethoden liegt keine ausreichende wissenschaftliche Evidenz vor. Sie können aber im

  1. Molecular imaging in neurological diseases; Molekulare Bildgebung bei neurologischen Erkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Reimold, M.; Fougere, C. la [Universitaetsklinikum Tuebingen, Abteilung Nuklearmedizin und Klinische Molekulare Bildgebung, Department Radiologie, Tuebingen (Germany)

    2016-07-15

    In neurodegeneration and in neuro-oncology, the standard imaging procedure, magnetic resonance imaging (MRI), shows limited sensitivity and specificity. Molecular imaging with specific positron-emission tomography (PET) and single-photon emission computed tomography (SPECT) tracers allows various molecular targets and metabolic processes to be assessed and is thus a valuable adjunct to MRI. Two important examples are referred to here: amino acid transport for neuro-oncological issues, and the recently approved PET tracers for detecting amyloid depositions during the preclinical stage of Alzheimer's disease. This review discusses the clinical relevance and indications for the following nuclear medicine imaging procedures: amyloid PET, {sup 18}F-fluorodeoxyglucose (FDG)-PET, and dopamine transporter (DaT)-SPECT for the diagnosis of dementia and the differential diagnosis of Parkinson's disease, in addition to amino acid PET for the diagnosis of brain tumors and somatostatin receptor imaging in meningioma. (orig.) [German] Die Magnetresonanztomographie (MRT) weist als Standardverfahren bei neurodegenerativen und neuroonkologischen Fragestellungen eine eingeschraenkte Sensitivitaet und Spezifitaet auf. Die nuklearmedizinische molekulare Bildgebung mit spezifischen Positronenemissionstomographie(PET)- und single-photon-emission-computed-tomography(SPECT)-Tracern ermoeglicht die Darstellung verschiedener molekularer Targets bzw. Stoffwechselprozesse und stellt damit eine wichtige Ergaenzung zur MRT dar. Hier sei exemplarisch auf die Darstellung des Aminosaeuretransports im Rahmen neuroonkologischer Fragestellungen verwiesen, sowie auf die bereits im praeklinischen Stadium der Alzheimer-Demenz nachweisbaren Amyloidablagerungen mit hierfuer seit Kurzem zugelassenen PET-Tracern. Dieser Uebersichtsbeitrag bespricht die klinische Bedeutung bzw. die Indikationen der folgenden nuklearmedizinischen Untersuchungsverfahren: der Amyloid-PET, der {sup 18}F

  2. Basic considerations in organ perfusion physiology.

    Science.gov (United States)

    Zimmerman, Michael A; Martin, Alicia; Hong, Johnny C

    2016-06-01

    Owing to a severe shortage of organs for patients with end-stage diseases, novel techniques in organ preservation and perfusion need to be studied and reviewed to increase the number of available organs for transplant. Many patients will die while waiting for an organ. To make organs from extended-criteria donors feasible, optimal conditions for pulsatile perfusion and the potential for organ reconditioning at implantation need to be addressed. Many techniques in organ preservation and perfusion are being studied. Several laboratories are studying the effects of temperature for organ perfusion. Two areas being studied are hypothermic and normothermic machine perfusion. In the area of organ preservation, new solutions are being studied such as a substrate-enriched, oxygen-saturated, and leukocyte-depleted perfusate to help with organ quality. Even with the strides being made in organ preservation and perfusion, there are still many unanswered questions. More studies will need to be done to find the optimal conditions for duration of perfusion in the cold phase, optimal perfusion solution, degree of oxygenation, and the addition of pharmacologic agents, to improve organ function and expand the organ pool.

  3. Tryptophanabhängige Synthese von indolhaltigen Pigmenten bei verschiedenen humanpathogenen Asco- und Basidiomyceten

    OpenAIRE

    Nies, Silke Marie

    2006-01-01

    Der Begriff "Pigment" beschreibt in erster Linie farbige Substanzen. Pigmente sind aber darüber hinaus für wichtige metabolische oder physiologische Prozesse verantwortlich. Im Reich der Pilze gibt es eine Vielzahl von Pigmenten. Zu ihnen zählen die Melanine, die Carotenoide, die Naphthoquinone, die Phenoxazine, die Flavonoide sowie indolhaltige Pigmente. Gewisse Indolderivate wurden von einer Arbeitsgruppe um Prof. Mayser 1998 erstmals bei der Hefe Malassezia furfur beschrieben, bei der ...

  4. Einflussfaktoren auf den persönlichen Stress bei Studienanfängern in der Humanmedizin

    OpenAIRE

    Schulze, Johannes; Duderstadt, Monika; Hodjat, Beheshta; Wu, Yue-Ying

    2013-01-01

    Die derzeitige Regelung der Zulassung zum Medizinstudium berücksichtigt die Abiturnote und Wartezeiten; universitäre Parameter können diese Kriterien modifizieren. Hierzu zählen z.B. die Leistungskurswahl, wie es an der Goethe-Universität Frankfurt gehandhabt wird. Im Rahmen der Untersuchung zu Stress und Resilienz bei Medizinstudenten haben wir bei den Studenten des 1. vorklinischen Semesters soziodemographische Daten erhoben, die einen Kohortenvergleich erlauben. Die chronische Stressbelast...

  5. Estimation of Satellite PCO Offsets for BeiDou based on MGEX Net Solution

    Science.gov (United States)

    Yize, Zhang; Junping, Chen; Bin, Wu; Jiexian, Wang

    2015-04-01

    BeiDou Satellite Navigation System currently has a total 14 satellites including GEO/IGSO/MEO satellites and providing a regional PNT service. Due to a lack of publicly available antenna phase center offsets (PCO) for the BeiDou satellites, conventional values of (+0.6 m, 0.0 m, +1.1 m) are recommended for orbit and clock determination of the GEO/IGSO/MEO satellites, which needs to be further estimation and refinement. In this paper, we propose a multi-GNSS network solution for the estimation of BeiDou satellite PCO. More than 35 ground stations of International GNSS MGEX tracking network are used to determine the BeiDou satellite PCO. In this strategy, the GPS and BeiDou satellite orbits and clocks are derived from IGS final products, and GPS satellite PCO and PCV are fixed according to igs08.atx. The BeiDou satellites PCO are estimated together with the station clock, troposphere delay and LC combination ambiguity parameter. Result shows that the RMS of phase residuals for all stations is 1.8cm and is 1.6m for code residual, respectively. The estimated PCO is different for each satellite. Appling the new PCO for precise point positioning, we found that the positioning error improves from 6cm to 2cm in height.

  6. Research Article. Improved Dual Frequency PPP Model Using GPS and BeiDou Observations

    Science.gov (United States)

    Afifi, A.; El-Rabbany, A.

    2017-02-01

    This paper introduces a new dual-frequency precise point positioning (PPP) model, which combines GPS and BeiDou observations. Combining GPS and BeiDou observations in a PPP model offers more visible satellites to the user, which is expected to enhance the satellite geometry and the overall PPP solution in comparison with GPSonly PPP solution. However, combining different GNSS constellations introduces additional biases, which require rigorous modelling, including GNSS time offset and hardware delays. In this research, ionosphere-free linear combination PPP model is developed. The additional biases, which result from combining the GPS and BeiDou observables, are lumped into a new unknown parameter identified as the inter-system bias. Natural Resources Canada's GPSPace PPP software is modified to enable a combined GPS/BeiDou PPP solution and to handle the newly introduced biases. A total of four data sets at four IGS stations are processed to verify the developed PPP model. Precise satellite orbit and clock products from the IGS-MGEX network are used to correct both of the GPS and BeiDou measurements. It is shown that a sub-decimeter positioning accuracy level and 25% reduction in the solution convergence time can be achieved with combining GPS and Bei-Dou observables in a PPP model, in comparison with the GPS-only PPP solution.

  7. Hyperventilation, cerebral perfusion, and syncope

    DEFF Research Database (Denmark)

    Immink, R V; Pott, F C; Secher, N H

    2014-01-01

    the contribution of a low PaCO2 to the early postural reduction in middle cerebral artery blood velocity is transient. HV together with postural stress does not reduce cerebral perfusion to such an extent that TLOC develops. However when HV is combined with cardiovascular stressors like cold immersion or reduced...... dioxide (PaCO2) and oxygen (PaO2) partial pressures so that hypercapnia/hypoxia increases and hypocapnia/hyperoxia reduces global cerebral blood flow. Cerebral hypoperfusion and TLOC have been associated with hypocapnia related to HV. Notwithstanding pronounced cerebrovascular effects of PaCO2...

  8. Kontrastmittelverstärkte Magnet-Resonanz-Urographie unter forcierter Diurese - Stellenwert in der Differentialdiagnostik bei Obstruktionen des oberen Harntraktes

    Directory of Open Access Journals (Sweden)

    Jung P

    2001-01-01

    Full Text Available Die Magnet-Resonanz-Urographie (MRU ist ein relativ neues Verfahren in der Diagnostik des oberen Harntraktes. Das Ziel dieser Studie war der Vergleich der Aussagefähigkeit der MRU unter Gabe von Gadolinium und Furosemid und dem konventionellen Urogramm (IVU in der Diagnostik der Ursache von Obstruktionen im Bereich des Harnleiters. 82 Patienten mit im IVU nachgewiesener Obstruktion des oberen Harntraktes oder urographisch stummer Niere bei sonographisch nachgewiesener Dilatation wurden der MRU zugeführt. Die Bilder beider Untersuchungsmethoden wurden von voneinander unabhängigen Untersuchern befundet. Zwei Urologen befundeten die IVU-Bilder, zwei Radiologen die MRU-Bilder, die Radiologen kannten die IVU-Diagnose nicht. Bei unklarer Diagnose wurden weitere Untersuchungen wie Computertomographie, retrograde Pyelographie oder Ureteroskopie durchgeführt. Die Diagnosen waren: Harnleitersteine bei 72 Patienten, Harnleitertumore bei 8 Patienten und extraureterale Tumore bei 2 Patienten. Eine richtige Diagnose bei den Steinpatienten wurde durch IVU bei 49 von 72 Patienten und durch MRU bei 64 von 72 Patienten gestellt. In dieser Patientengruppe wurden durch die MRU zwei falsche Diagnosen gestellt. Fehlende Kontrastmittelausscheidung war der Hauptgrund für Versagen der IVU. 3 der 8 Patienten mit Harnleitertumoren wurden durch die IVU richtig dignostiziert, bei dreien wurde eine falsche Diagnose gestellt. Durch die MRU konnten in dieser Gruppe 7 von 8 Patienten korrekt diagnostiziert werden, es wurde keine falsche Diagnose erhoben. IVU wird zunächst die Standarduntersuchungstechnik zur Darstellung des oberen Harntraktes bleiben, aber durch diese Studie konnte die Möglichkeit gezeigt werden, die in der MRU in Kombination mit Gadolinium und Furosemid liegt. Die größte Bedeutung dieser Untersuchung liegt in der urographisch stummen Niere, bei Untersuchungen in der Schwangerschaft, bei Kindern und bei Patienten mit Kontrastmittelunverträglichkeit.

  9. Clinical application of cerebral dynamic perfusion studies

    International Nuclear Information System (INIS)

    DeLand, F.H.

    1975-01-01

    Radionuclide cerebral perfusion studies are assuming a far greater importance in the detection and differential diagnosis of cerebral lesions. Perfusion studies not only contribute to the differential diagnosis of lesions but in certain cases are the preferred methods by which more accurate clinical interpretations can be made. The characteristic blood flow of arterio-venous malformations readily differentiates this lesion from neoplasms. The decreased perfusion or absent perfusion observed in cerebral infarctions is diagnostic without concurrent evidence from static images. Changes in rates and direction of blood flow contribute fundamental information to the status of stenosis and vascular occlusion and, in addition, offer valuable information on the competency and routes of collateral circulation. The degree of cerebral perfusion after cerebral vascular accidents appears to be directly related to patient recovery, particularly muscular function. Cerebral perfusion adds a new parameter in the diagnosis of subdural haematomas and concussion and in the differentiation of obscuring radioactivity from superficial trauma. Although pictorial displays of perfusion blood flow will offer information in most cerebral vascular problems, the addition of computer analysis better defines temporal relationships of regional blood flow, quantitative changes in flow and the detection of the more subtle increases or decreases in cerebral blood flow. The status of radionuclide cerebral perfusion studies has taken on an importance making it the primary modality for the diagnosis of cerebral lesions. (author)

  10. Analgetische Wirkungen lokalanästhetischer Salbe bei der Kryotherapie von Warzen: eine Meta-analyse randomisierter Studien.

    Science.gov (United States)

    Lee, Chin-Yu; Tung, Tao-Hsin; Liu, Chia-Yu; Wang, Shu-Hui; Chi, Ching-Chi

    2018-03-01

    Lokalanästhetische Creme (LAC) wird zur Analgesie bei verschiedenen Verfahren angewendet. Ihre analgetische Wirkung bei der Kryotherapie von Warzen ist jedoch unklar. Wir untersuchten die Wirkung von LAC bei der Kryotherapie von Warzen. Wir erstellten eine systematische Übersicht und Meta-analyse randomisierter kontrollierter Studien (RCTs) zu Wirkungen von LAC bei der Kryotherapie von Warzen. Dazu haben wir MEDLINE, CENTRAL und EMBASE am 31. März 2017 nach relevanten RCTs durchsucht. Zwei Autoren wählten unabhängig voneinander die Studien aus, schätzten das Verzerrungsrisiko ab und extrahierten Daten. Meinungsdifferenzen wurden durch Diskussion mit einem dritten Autor gelöst. Wir schlossen drei RCTs mit 228 Teilnehmern ein. Zwei dieser RCTs bergen ein hohes Risiko einer selektiven Berichterstattung (reporting bias), wobei bei einer der beiden Studien auch das Risiko anderer Bias hoch ist. Lokalanästhetische Creme senkte bei Kindern den Schmerz bei der Kryotherapie von Warzen auf verhornter Haut (visuelle Analogskala, mittlere Differenz -20,80; 95 % - Konfidenzintervall -40,71 bis -0,89), jedoch nicht bei Erwachsenen oder auf nicht verhornter Haut von Erwachsenen oder Kindern. Die routinemäßige Verwendung von LAC ≤ 60 min bei der Kryotherapie von Warzen wird nicht durch Literaturbelege gestützt. © 2018 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  11. Dynamic contrast enhanced MRI for perfusion quantification

    DEFF Research Database (Denmark)

    Andersen, Irene Klærke

    2002-01-01

    Magnetic resonance imaging, during bolus passage of a paramagnetic contrast agent, is used world-wide to obtain parameters that reflect the pathological state of tissue. Abnormal perfusion occurs in diseases such as stoke and tumour. Consequently, perfusion quantication could have signi cant...... the contrastagent concentration, [Ca], and the changes in R2 or R 2 has been questioned. In this thesis, an MRI scanner sequence for detection of the longitudinal relaxation rate, R1 during bolus passage was modied for brain perfusion measurements, since the linearity between the changes in R1 and [Ca] is expected...... to be more robust. Successful brain perfusion quantication based on R1 weighted signals has not previously been reported, due to the poor signal to noise ratio of the images. Initial experiments reported in this thesis show that improved sequence may provide more accurate perfusion estimates in the brain...

  12. Methodology for ventilation/perfusion SPECT

    DEFF Research Database (Denmark)

    Bajc, Marika; Neilly, Brian; Miniati, Massimo

    2010-01-01

    radiolabeled liquid aerosols are not restricted to the presence of obstructive lung disease. Radiolabeled macroaggregated human albumin is the imaging agent of choice for perfusion scintigraphy. An optimal combination of nuclide activities and acquisition times for ventilation and perfusion, collimators......Ventilation/perfusion single-photon emission computed tomography (V/Q SPECT) is the scintigraphic technique of choice for the diagnosis of pulmonary embolism and many other disorders that affect lung function. Data from recent ventilation studies show that the theoretic advantages of Technegas over......, and imaging matrix yields an adequate V/Q SPECT study in approximately 20 minutes of imaging time. The recommended protocol based on the patient remaining in an unchanged position during the initial ventilation study and the perfusion study allows presentation of matching ventilation and perfusion slices...

  13. Brain Perfusion Changes in Intracerebral Hemorrhage

    International Nuclear Information System (INIS)

    Mititelu, R.; Mazilu, C.; Ghita, S.; Rimbu, A.; Marinescu, G.; Codorean, I.; Bajenaru, O.

    2006-01-01

    Full text: Purpose: Despite the latest advances in medical treatment and neuro critical care, patients suffering spontaneous intracerebral hemorrhage (SICH) still have a very poor prognosis, with a greater mortality and larger neurological deficits at the survivors than for ischemic stroke. Many authors have shown that there are many mechanisms involved in the pathology of SICH: edema, ischemia, inflammation, apoptosis. All of these factors are affecting brain tissue surrounding hematoma and are responsible of the progressive neurological deterioration; most of these damages are not revealed by anatomical imaging techniques. The aim of our study was to asses the role of brain perfusion SPECT in demonstrating perfusion changes in SICH patients. Method: 17 SICH pts were studied. All pts underwent same day CT and brain SPECT with 99mTcHMPAO, 24h-5d from onset of stroke. Results: 14/17 pts showed a larger perfusion defect than expected after CT. In 2 pts hematoma diameter was comparable on CT and SPECT; 1pt had quasinormal aspect of SPECT study. In pts with larger defects, SPECT revealed a large cold spot with similar size compared with CT, and a surrounding hypo perfused area. 6/17 pts revealed cortical hyper perfusion adjacent to hypo perfused area and corresponding to a normal-appearing brain tissue on CT. In 3 pts we found crossed cerebellar diaskisis.In 2 pts we found cortical hypo perfused area in the contralateral cortex, with normal appearing brain tissue on CT. Conclusions: Brain perfusion SPECT revealed different types of perfusion changes in the brain tissue surrounding hematoma. These areas contain viable brain tissue that may be a target for future ne uroprotective strategies. Further studies are definitely required to demonstrate prognostic significance of these changes, but we can conclude that brain perfusion SPECT can play an important role in SICH, by early demonstrating functional changes responsible of clinical deterioration, thus allowing prompt

  14. Gas hydrates in gas storage caverns; Gashydrate bei der Gaskavernenspeicherung

    Energy Technology Data Exchange (ETDEWEB)

    Groenefeld, P. [Kavernen Bau- und Betriebs-GmbH, Hannover (Germany)

    1997-12-31

    Given appropriate pressure and temperature conditions the storage of natural gas in salt caverns can lead to the formation of gas hydrates in the producing well or aboveground operating facilities. This is attributable to the stored gas becoming more or less saturated with water vapour. The present contribution describes the humidity, pressure, and temperature conditions conducive to gas hydrate formation. It also deals with the reduction of the gas removal capacity resulting from gas hydrate formation, and possible measures for preventing hydrate formation such as injection of glycol, the reduction of water vapour absorption from the cavern sump, and dewatering of the cavern sump. (MSK) [Deutsch] Bei der Speicherung von Erdgas in Salzkavernen kann es unter entsprechenden Druck- und Temperaturverhaeltnissen zur Gashydratbildung in den Foerdersonden oder obertaegigen Betriebseinrichtungen kommen, weil sich das eingelagerte Gas mehr oder weniger mit Wasserdampf aufsaettigt. Im Folgenden werden die Feuchtigkeits-, Druck- und Temperaturbedingungen, die zur Hydratbildung fuehren erlaeutert. Ebenso werden die Verringerung der Auslagerungskapazitaet durch die Hydratbildung, Massnahmen zur Verhinderung der Hydratbildung wie die Injektion von Glykol, die Verringerung der Wasserdampfaufnahme aus dem Kavernensumpf und die Entwaesserung der Kavernensumpfs selbst beschrieben.

  15. Regional heterogeneity of myocardial perfusion in healthy human myocardium: assessment with magnetic resonance perfusion imaging.

    Science.gov (United States)

    Muehling, Olaf M; Jerosch-Herold, Michael; Panse, Prasad; Zenovich, Andrey; Wilson, Betsy V; Wilson, Robert F; Wilke, Norbert

    2004-01-01

    The knowledge of myocardial perfusion in healthy volunteers is fundamental for evaluation of patients with ischemic heart disease. The study was conducted to determine range, regional variability, and transmural gradient of myocardial perfusion in normal volunteers with Magnetic Resonance Perfusion Imaging (MRPI). Perfusion was assessed in 17 healthy volunteers (age: 20-47 yr, 11 males) at rest and adenosine-induced hyperemia using a 1.5 T MR scanner. Perfusion was quantified (mL/g/min) for the transmural myocardium and separately for the endo- and epimyocardium in the anterior, lateral, posterior, and septal left ventricular wall using the Fermi model for constrained deconvolution. Regional variabilities for resting, hyperemic perfusion, and perfusion reserve were 22 +/- 8%, 21 +/- 10%, and 35 +/- 18%. Mean resting, hyperemic perfusion, and perfusion reserve were 1.1 +/- 0.4 mL/g/min, 4.2 +/- 1.1 mL/g/min, and 4.1 +/- 1.4. Perfusion in the septum was higher at rest (1.3 +/- 0.3 mL/g/min vs. 1.0 +/- 0.3 mL/g/min, p < 0.05) and lower during hyperemia (3.6 +/- 0.8 mL/g/min vs. 4.5 +/- 1.1 mL/g/min, p < 0.03), resulting in a reduced perfusion reserve (PR) (3.2 +/- 0.9 vs. 4.5 +/- 1.4, p < 0.01) in the septum vs. the combined anterior, lateral, and posterior segments. Resting (0.9 +/- 0.3 mL/g/min vs. 1.4 +/- 0.5 mL/g/min, p < 0.01), but not hyperemic perfusion, was lower in the epi- vs. endomyocardium, resulting in a higher epimyocardial PR (4.8 +/- 1.8 vs. 3.5 +/- 1.4, p < 0.01) in all regions but the septum, where endo- and epimyocardial perfusion and perfusion reserve were not different. A considerable regional variability of myocardial perfusion was confirmed with MRPI. The exceptional anatomical position of the septum is reflected by the lack of a perfusion gradient, which was demonstrated in all other regions but the septum.

  16. Kyphoplastie als palliative Therapieoption bei pathologischen Frakturen der Brust- und Lendenwirbelsäule

    Directory of Open Access Journals (Sweden)

    Hartwig E

    2004-01-01

    Full Text Available Bedingt durch Fortschritte in der Behandlung von Tumoren hat sich die Lebenserwartung von Krebspatienten deutlich verbessert. Jedoch steigt hiermit auch die Inzidenz von Knochenmetastasen. Mit wenigen Ausnahmen, die primären Knochentumoren betreffend, ist die Art der Behandlung dieser Läsionen in der Regel palliativ. Durch operatives Intervenieren muß bei diesen Patienten ein maximaler palliativer Effekt bei minimaler Morbidität und Mortalität erzielt werden. Die vorwiegenden Ziele sind Schmerzreduktion unter Erhalt der Stabilität und Funktion. Durch die Kyphoplastie wurden Zementierungsverfahren an der Wirbelsäule auch für pathologische Frakturen auf dem Boden metastatischer Manifestationen elegibel. In einer telefonischen Evaluation von 10 Patienten konnte die Wertigkeit des Verfahrens in der palliativen Situation bei Patienten mit Wirbelsäulenmetastasen gezeigt werden.

  17. Radiotherapy for treatment of induratio penis plastica; Strahlentherapie bei Induratio penis plastica

    Energy Technology Data Exchange (ETDEWEB)

    Bruns, F.; Kardels, B.; Schaefer, U.; Schoenekaes, K.; Willich, N. [Westfaelische Wilhelms-Univ., Muenster (Germany). Klinik und Poliklinik fuer Strahlentherapie-Radioonkologie

    1999-06-01

    Radiotherapy is shown to be an effective, low-cost and non-invasive modality for treatment of induratio penis plastica. Its efficiency could be proven especially for inflammatory stages of the disease, or as an alternative after failure of conventional treatment. A total dose of no more than 20-25 Gy was found to achieve clear improvements in two thirds of the patients treated, while avoiding at the same time cosmetically disadvantageous late effects. (orig./CB) [Deutsch] Die Strahlentherapie ist eine wirksame, kostenguenstige und nicht-invasive Behandlungsmoeglichkeit bei Induratio penis plastica. Ihren Stellenwert konnte sie insbesondere im inflammatorischen Stadium und nach Versagen anderer konservativer Therapieansaetze zeigen. Eine Gesamteinstrahldosis von 20-25 Gy reicht aus, um bei 2/3 der Patienten eine deutliche Besserung der Symptomatik zu erzielen bei gleichzeitiger Vermeidung kosmetisch relevanter Spaetnebenwirkungen. (orig.)

  18. Ventilation-perfused studies using SPECT

    International Nuclear Information System (INIS)

    Zwijnenburg, A.

    1989-01-01

    A method for the quantitative analysis of ventilation-perfusion SPECT studies is decribed and an effort is made to evaluate its usefullness. The technical details of the emthod are described. In the the transaxial reconstructions of the tomographic studies the contour of the lungs is detected and regional values of lung volume, ventilation, perfusion and ventilation-perfusion ratios are calculated. The method is operator independent. The lung volume calculations from the SPECT studies are validated by comparing them with lung volume measurements using the helium dilution technique. A good correlation (r=0.91) was found between the two volumes. SPECT volume was greater than the volume measured with helium dilution, which was attributed to non-gas-containing structures in the. lungs. The use of ventilation-perfusion ratio SPECT is described to evaluate the effect of ionizing radiation on the lungs in patients treated with mantle field irradiation for Hodgkin's disease. Perfusion changes appear as early as 2 months after the start of irradiation. Ventilation changes appear later and relatively minor. No changes are seen outside the radiation portals. The ventilation-perfusion inequality in pulmonary sarcoidosis is treated. It is suggested that the decrease D LCO in these patients may be partly due to an even distribution of ventilation perfusion ratios. An effort is made to establish the properties of a new tracer used for the assessment of the metabolic function of the pulmonary endothelium. The lung uptake of I-123 IMP mimics the distribution of a perfusion tracer and it is suggested that this tracer may be useful for the early detection of pulmonary vascular damage, even when blood flow is still intact. Some aspects of the use of Kr-81m as a ventilation tracer are discussed as well as the effect of noise on Kr-81m SPECT reconstructions. (author). 146 refs.; 39 figs.; 8 tabs

  19. Vicarious audiovisual learning in perfusion education.

    Science.gov (United States)

    Rath, Thomas E; Holt, David W

    2010-12-01

    Perfusion technology is a mechanical and visual science traditionally taught with didactic instruction combined with clinical experience. It is difficult to provide perfusion students the opportunity to experience difficult clinical situations, set up complex perfusion equipment, or observe corrective measures taken during catastrophic events because of patient safety concerns. Although high fidelity simulators offer exciting opportunities for future perfusion training, we explore the use of a less costly low fidelity form of simulation instruction, vicarious audiovisual learning. Two low fidelity modes of instruction; description with text and a vicarious, first person audiovisual production depicting the same content were compared. Students (n = 37) sampled from five North American perfusion schools were prospectively randomized to one of two online learning modules, text or video.These modules described the setup and operation of the MAQUET ROTAFLOW stand-alone centrifugal console and pump. Using a 10 question multiple-choice test, students were assessed immediately after viewing the module (test #1) and then again 2 weeks later (test #2) to determine cognition and recall of the module content. In addition, students completed a questionnaire assessing the learning preferences of today's perfusion student. Mean test scores from test #1 for video learners (n = 18) were significantly higher (88.89%) than for text learners (n = 19) (74.74%), (p learning module than text learners. Vicarious audiovisual learning modules may be an efficacious, low cost means of delivering perfusion training on subjects such as equipment setup and operation. Video learning appears to improve cognition and retention of learned content and may play an important role in how we teach perfusion in the future, as simulation technology becomes more prevalent.

  20. Measurement of myocardial perfusion using magnetic resonance

    DEFF Research Database (Denmark)

    Fritz-Hansen, T.; Jensen, L.T.; Larsson, H.B.

    2008-01-01

    Cardiac magnetic resonance imaging (MRI) has evolved rapidly. Recent developments have made non-invasive quantitative myocardial perfusion measurements possible. MRI is particularly attractive due to its high spatial resolution and because it does not involve ionising radiation. This paper reviews...... myocardial perfusion imaging with MR contrast agents: methods, validation and experiences from clinical studies. Unresolved issues still restrict the use of these techniques to research although clinical applications are within reach Udgivelsesdato: 2008/12/8...

  1. 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

  2. Apophyseal damage in adolescent athlete; Apophysenschaeden bei jugendlichen Sportlern

    Energy Technology Data Exchange (ETDEWEB)

    Nehrer, S.; Huber, W.; Dirisamer, A.; Kainberger, F. [Universitaetsklinik fuer Orthopaedie, Wien (Austria)

    2002-10-01

    The increasing demands on the adolescent athlete in high perfomance sports puts high biomechanical stress on the growing structures of the active and passive locomotor system. The ''growing factor'' itself increases stretching forces on tendon insertions, which are often overloaded when a physical demanding sport is performed additionally. The apophysis is an ossification nucleus near the tendon insertion, which appears before the growing age resumes and these apophysis finally fuses with the adjacent bone. The tensile forces from vigorous sports activity leads to a chronic or acute avulsion of the ossifying tendon insertion. The radiological appearance of this apophyseal damage with ossification and osteolytic processes is sometimes difficult with respect to differential diagnoses. Apophyseal impairment is associated with pain, tenderness to palpation and decreased muscle function. If it is not diagnosed and treated properly it can lead to end of career in many adolescent athletes. (orig.) [German] Die Leistungsentwicklung im Spitzensport erfordert in zunehmendem Masse die Aufnahme eines zielorientierten Trainingsprozesses im Kindes- und Jugendalter und bringt junge Sportler in hohe Belastungsbereiche. Der aktive und passive Bewegungsapparat wird hier in der Phase der Entwicklung und des Wachstums gefordert, und leider auch manchmal ueberfordert. Die vermehrte Zugwirkung der Sehnenansaetze im Wachstum und das intensive Betreiben von Sport fuehren zur Ueberlastung der Sehneninsertionen. Die Apophysen, als Ossifikationskerne in Sehnen- und Muskelinsertionen, sind empfindliche Wachstumsstrukturen, die unter dieser biomechanischen Ueberlastungssituation Schaeden erleiden, die bereits als sportspezifische Veraenderungen bei Kindern und Jugendlichen beschrieben werden. Typische radiologische Befunde koennen v. a. im Bereich des Beckens und der grossen Gelenke gefunden werden. Ihre Charakteristik und Differenzialdiagnostik stellt den sportmedizinisch

  3. Imaging of hip joint arthroplasty; Bildgebung bei Hueftgelenkendoprothesen

    Energy Technology Data Exchange (ETDEWEB)

    Mayerhoefer, M.E.; Fruehwald-Pallamar, J.; Czerny, C. [Univ.-Klinik fuer Radiodiagnostik, Medizinische Universitaet Wien, Abteilung fuer Neuroradiologie und Muskuloskelettale Radiologie, Wien (Austria)

    2009-05-15

    . Computertomographie (CT) und Magnetresonanztomographie (MRT) haben sich im Laufe der Jahre fuer spezielle Fragestellungen und bei unklarem projektionsradiographischem Befund etabliert. So lassen sich entzuendliche Prozesse mit (CT) oder auch ohne (MRT) Kontrastmittel ausgezeichnet beurteilen. Unabhaengig von der bildgebenden Modalitaet ist in jedem Fall eine Korrelation mit der klinischen Symptomatik des Patienten unerlaesslich. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-03-01

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

  5. CT perfusion study of neck lymph nodes

    International Nuclear Information System (INIS)

    Zhong Jin; Liu Jun; Hua Rui; Qiao Hui; Gong Yi

    2011-01-01

    Objective: To study the CT perfusion features of various lymph nodes in the neck. Methods: Dynamic perfusion CT scanning was performed in 83 neck lymph nodes proved by pathology, including tuberculosis lymph nodes, lymphoma and metastatic lymph nodes. The shapes, blood flow modes, and perfusion parameters of these lymph nodes were compared among 3 groups. Statistical analysis of L/T and CT perfusion parameters was performed by one-way ANOVA and LSD test. Results: The values of MTT of tuberculosis lymph nodes, lymphoma and metastatic lymph nodes were (28.13±5.08), (31.08±5.82), and (11.24±5.31) s, respectively. The MTT of metastatic lymph nodes was statistically lower than that of tuberculosis lymph nodes and lymphoma (P -1 · 100 g -1 , respectively. The values of BV were (24.68±2.84), (25.30±3.16), and (25.15± 8.81) ml·100 g -1 respectively. The values of TTP were (40.90±8.85), (40.67±6.45), and (40.98±6.62) s, respectively. There were no significant differences in L/T, BF, BV and TTP among tuberculosis lymph nodes, lymphoma and metastatic lymph nodes (P>0.05). Conclusion: CT perfusion, especially combination functional imaging with perfusion images may be helpful in judging the nature of neck lymph nodes. (authors)

  6. Tc-99m-bicisate (ECD)-brain-SPECT in rapidly progressive dementia; Hirn-SPECT mit Tc-99m-Bicisat (ECD) bei rasch progredientem dementiellen Syndrom

    Energy Technology Data Exchange (ETDEWEB)

    Marienhagen, J.; Eilles, C. [Regensburg Univ. (Germany). Abt. fuer Nuklearmedizin; Weingaertner, U.; Blaha, L. [Bezirkskrankenhaus Mainkofen (Germany). Psychiatrische Klinik; Zerr, I.; Poser, S. [Goettingen Univ. (Germany). Klinik und Poliklinik fuer Neurologie

    1999-07-01

    We present a 61-year-old male patient with progressive dementia. A brain SPECT with Tc-99m-bicisate was performed for confirmation of clinically suspected Alzheimer-dementia. At the time of the SPECT-investigation marked apraxia and aphasia besides severe dementia were present. Electrophysiological as well as anatomical neuroimaging findings showed non-diagnostic alterations. SPECT revealed distinct perfusion defects, which made Alzheimer Dementia unlikely. The further course of the patient was determined by rapidly progressive deterioration with development of akinetic mutism. Thereafter, increased levels of neuron-specific enolase as well as 14-3-3 proteins were found in the cerebro-spinal fluid (CSF). The patient finally died with signs of cerebral decortication. Due to the clinical course and the CSF-findings the patient's final diagnosis was Creutzfeld-Jakob-disease, nevertheless no autopsy was performed. The presented case report underscores the clinical utility of perfusion brain SPECT in the differential diagnosis of dementias. (orig.) [German] Wir berichten ueber einen 61jaehrigen Patienten mit progredientem dementiellen Syndrom, der unter der Verdachtsdiagnose einer Demenz vom Alzheimer-Typ (DAT) zur Hirn-SPECT-Untersuchung mit TC-99m-Bicisat (ECD) vorgestellt wurde. Zum Untersuchungszeitpunkt bestanden neben dem Vollbild einer Demenz eine ausgepraegte Apraxie und Aphasie bei unspezifischen Veraenderungen im EEG sowie der neuroradiologischen Bildgebung. In der Hirn-SPECT-Untersuchung fanden sich fuer eine DAT untypische ausgedehnte, vorwiegend rechtshemisphaerische Perfusionsstoerungen. Im weiteren Verlauf rasche Progredienz des Krankheitsbildes mit Entwicklung eines akinetischen Mutismus sowie Nachweis erhoehter Werte der neuronspezifischen Enolase und des 14-3-3-Proteins im Liquor. Der Patient verstarb schliesslich unter dem Bild einer Decortication. Aufgrund des klinischen Verlaufs sowie der Liquorbefunde wurde, da eine autoptische Befundsicherung

  7. Harnableitung bei Kindern und Jugendlichen mit neurogener Blasenfunktionsstörung: auch langfristig eine sichere Therapieoption?

    Directory of Open Access Journals (Sweden)

    Stein R

    2002-01-01

    Full Text Available Einleitung: Pharmakotherapie, der saubere Einmalkatheterismus (clean intermittent catheterization = CIC und die Infektionsprophylaxe sind die drei Säulen der konservativen Therapie bei Patienten mit neurogener Blasenfunktionsstörung. Während der Pubertät werden die Patienten zunehmend unabhängiger vom Elternhaus. Gleichzeitig nimmt jedoch die Compliance der Medikamenteneinnahme und der Durchführung des regelmäßigen CIC ab. Der orthopädische und/oder neurologische Status kann sich ebenfalls verändern. Dies kann letztlich zum Fehlschlagen der konservativen Therapie (Inkontinenz, Restharn, Verschlechterung der Funktion des oberen Harntraktes führen. In einem multidisziplinären Team wird diese Problematik der Kinder und Jugendlichen unter Berücksichtigung der Wünsche des Patienten als auch der medizinischen Ziele (z. B. Schutz der Nierenfunktion in unserer Klinik diskutiert. Die Harnableitung wurde hierbei in einigen Fällen als notwendige Kompromißlösung angesehen. In der vorliegenden retrospektiven Studie untersuchten wir, ob die Harnableitung auch langfristig ein sicheres Verfahren darstellt. Material und Methode: Zwischen 1967 und 1997 erfolgte bei 149 Kindern und Heranwachsenden die Anlage einer Harnableitung. 129 Patienten konnten durchschnittlich 11,8 Jahre (0,8-28,5 nachbeobachtet werden. Das durchschnittliche Alter bei der Operation betrug 12,1 Jahre (0,8-20. Ein Colon-Conduit wurde bei 59 Patienten (in der Mehrzahl der Fälle vor der Ära des CIC und der kontinenten Harnableitung angelegt, eine orthotope Blasensubstitution erfolgte bei 12, eine kontinente kutane Harnableitung bei 58 Patienten (50 % Rollstuhlfahrer. Ergebnisse: Der obere Harntrakt blieb bei 95-97 % der renoureteralen Einheiten (RUE stabil, bzw. verbesserte sich. Alle Patienten mit einer orthotopen Blasensubstitution sind tagsüber kontinent; eine Patientin benötigt zur Sicherheit zeitweise eine Vorlage während der Nacht. 7 der 12 Patienten führen einen

  8. PC-BEIS: a personal computer version of the biogenic emissions inventory system

    International Nuclear Information System (INIS)

    Pierce, T.E.; Waldruff, P.S.

    1991-01-01

    The US Environmental Protection Agency's Biogenic Emissions Inventory System (BEIS) has been adapted for use on IBM-compatible personal computers (PCs). PC-BEIS estimates hourly emissions of isoprene, α-pinene, other monoterpenes, and unidentified hydrocarbons for any county in the contiguous United States. To run the program, users must provide hourly data on ambient temperature, relative humidity, wind speed, cloud cover, and a code that identifies the particular county. This paper provides an overview of the method used to calculate biogenic emissions, shows an example application, and gives information on how to obtain a copy of the program

  9. Methodik zur Ermittlung von Emissionsfaktoren und Minderungsmaßnahmen bei aufgewirbelten Feinstaubpartikeln auf befestigten Fahrbahnen

    OpenAIRE

    EL-Waraki, M. Sami

    2009-01-01

    Seit vielen Jahrzehnten ist bekannt, dass die Feinstaubbelastung in Städten und Ballungsgebieten zunimmt. Menschen, Tiere, Pflanzen, Boden, Wasser und Atmosphäre werden durch diesen Feinstaub belastet. Im Allgemeinen wird der Straßenverkehr als Hauptverursacher für Immissionswertüberschreitungen angesehen, während die durch industrielle Prozesse verursachten Feinstaubemissionen rückläufig sind. Er hat sowohl bei den primär emittierten als auch bei den sekundär gebildeten Partik...

  10. Technical aspects of MR perfusion

    International Nuclear Information System (INIS)

    Sourbron, Steven

    2010-01-01

    The most common methods for measuring perfusion with MRI are arterial spin labelling (ASL), dynamic susceptibility contrast (DSC-MRI), and T 1 -weighted dynamic contrast enhancement (DCE-MRI). This review focuses on the latter approach, which is by far the most common in the body and produces measures of capillary permeability as well. The aim is to present a concise but complete overview of the technical issues involved in DCE-MRI data acquisition and analysis. For details the reader is referred to the references. The presentation of the topic is essentially generic and focuses on technical aspects that are common to all DCE-MRI measurements. For organ-specific problems and illustrations, we refer to the other papers in this issue. In Section 1 'Theory' the basic quantities are defined, and the physical mechanisms are presented that provide a relation between the hemodynamic parameters and the DCE-MRI signal. Section 2 'Data acquisition' discusses the issues involved in the design of an optimal measurement protocol. Section 3 'Data analysis' summarizes the steps that need to be taken to determine the hemodynamic parameters from the measured data.

  11. Abnormal perfusion on myocardial perfusion SPECT in patients with WPW syndrome: clinical implications

    International Nuclear Information System (INIS)

    Kang, Do Young; Cha, Kwang Soo; Kim, Moo Hyun; Kim, Young Dae; Kim, Duk Kyu

    2001-01-01

    Myocardial perfusion is altered significantly in patients with rhythm disturbances such as CLBBB and right ventricular pacing rhythm. Abnormal myocardial perfusion may be caused by ventricular preexcitation, but its location, extent, severity and correlation with accessory pathway (AP) are not established. We evaluated perfusion patterns on SPECT in patients with WPW syndrome. Adenosine Tc-99m MIBI or Tl-201 myocardial SPECT with or without coronary angiography were performed in 11 patients with WPW syndrome. Perfusion defects (PD) were compared to AP location based on ECG or electrophysiologic study. Small to large extent (11.0 8.5%, range: 0 35%) and mild to moderate severity (-71.8 42.7%, range: -217 0%) of reversible (n=9) or fixed (n=1) perfusion defects were noted. One patient with right free wall AP showed normal. Other defect locations were as follows. Myocardial perfusion defect showed variable extent, severity and location in patients with WPW syndrome. It was not specifically correlated with location of accessory pathway, but most of all patients were abnormal perfusion pattern. Therefore myocardial perfusion SPECT was interpreted carefully in patients with WPW syndrome

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-02-01

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

  13. GPU-accelerated voxelwise hepatic perfusion quantification.

    Science.gov (United States)

    Wang, H; Cao, Y

    2012-09-07

    Voxelwise quantification of hepatic perfusion parameters from dynamic contrast enhanced (DCE) imaging greatly contributes to assessment of liver function in response to radiation therapy. However, the efficiency of the estimation of hepatic perfusion parameters voxel-by-voxel in the whole liver using a dual-input single-compartment model requires substantial improvement for routine clinical applications. In this paper, we utilize the parallel computation power of a graphics processing unit (GPU) to accelerate the computation, while maintaining the same accuracy as the conventional method. Using compute unified device architecture-GPU, the hepatic perfusion computations over multiple voxels are run across the GPU blocks concurrently but independently. At each voxel, nonlinear least-squares fitting the time series of the liver DCE data to the compartmental model is distributed to multiple threads in a block, and the computations of different time points are performed simultaneously and synchronically. An efficient fast Fourier transform in a block is also developed for the convolution computation in the model. The GPU computations of the voxel-by-voxel hepatic perfusion images are compared with ones by the CPU using the simulated DCE data and the experimental DCE MR images from patients. The computation speed is improved by 30 times using a NVIDIA Tesla C2050 GPU compared to a 2.67 GHz Intel Xeon CPU processor. To obtain liver perfusion maps with 626 400 voxels in a patient's liver, it takes 0.9 min with the GPU-accelerated voxelwise computation, compared to 110 min with the CPU, while both methods result in perfusion parameters differences less than 10(-6). The method will be useful for generating liver perfusion images in clinical settings.

  14. GPU-Accelerated Voxelwise Hepatic Perfusion Quantification

    Science.gov (United States)

    Wang, H; Cao, Y

    2012-01-01

    Voxelwise quantification of hepatic perfusion parameters from dynamic contrast enhanced (DCE) imaging greatly contributes to assessment of liver function in response to radiation therapy. However, the efficiency of the estimation of hepatic perfusion parameters voxel-by-voxel in the whole liver using a dual-input single-compartment model requires substantial improvement for routine clinical applications. In this paper, we utilize the parallel computation power of a graphics processing unit (GPU) to accelerate the computation, while maintaining the same accuracy as the conventional method. Using CUDA-GPU, the hepatic perfusion computations over multiple voxels are run across the GPU blocks concurrently but independently. At each voxel, non-linear least squares fitting the time series of the liver DCE data to the compartmental model is distributed to multiple threads in a block, and the computations of different time points are performed simultaneously and synchronically. An efficient fast Fourier transform in a block is also developed for the convolution computation in the model. The GPU computations of the voxel-by-voxel hepatic perfusion images are compared with ones by the CPU using the simulated DCE data and the experimental DCE MR images from patients. The computation speed is improved by 30 times using a NVIDIA Tesla C2050 GPU compared to a 2.67 GHz Intel Xeon CPU processor. To obtain liver perfusion maps with 626400 voxels in a patient’s liver, it takes 0.9 min with the GPU-accelerated voxelwise computation, compared to 110 min with the CPU, while both methods result in perfusion parameters differences less than 10−6. The method will be useful for generating liver perfusion images in clinical settings. PMID:22892645

  15. Analgesic interventions for spinal diseases; Schmerztherapeutische Ansaetze bei Wirbelsaeulenerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-09-15

    Zuordnung kann durch spezielle Nervenblockaden erfolgen. Voraussetzung zur Durchfuehrung einer diagnostischen Nervenblockade sind eine ausfuehrliche Schmerzanamnese und Untersuchung des Patienten vor der Blockade. Bei ca. 15-45% der Patienten sind die Facettengelenke Ursache der Rueckenschmerzen. Eine Anaesthesie der Facettengelenke kann durch direkte intraartikulaere Applikation des Lokalanaesthetikums oder durch Blockade des Ramus medialis des hinteren Asts von jeweils 2 Spinalnerven erfolgen. Am einfachsten ist eine computertomographisch gesteuerte Facettenblockade. (orig.)

  16. The Relation Between Perfusion Pattern of Hepatic Artery Perfusion Scintigraphy and Response to Y-90 Microsphere Therapy

    Directory of Open Access Journals (Sweden)

    Bilge Volkan-Salancı

    2013-12-01

    Full Text Available Objective: Hepatic artery perfusion scintigraphy is a routine procedure for patient evaluation before Y-90 radiomicrosphere therapy and mostly used for prediction of extrahepatic leakage. Moreover, it also displays perfusion pattern of tumours, which is an important parameter on success of the therapy. The aim of this study is to assess the relation between the perfusion pattern on hepatic artery perfusion scintigraphy and radiomicrosphere therapy response. Methods: A total of 99 radiomicrosphere therapy applications were carried out in 80 patients (M/F: 55/25. Results: Heterogeneous and diffuse perfusion patterns were observed in 47 patients and 52 patients, respectively. The patients with diffuse perfusion pattern had better therapy response both on FDG PET/CT (p= 0.04 and CT (p=0.008 when compared to those with heterogenous perfusion pattern. Conclusion: Perfusion pattern observed on hepatic artery perfusion scintigraphy may be a successful predictor of early response to radiomicrosphere therapy

  17. Körperdysmorphe Symptome, soziale Anpassung und Motivation zu psychotherapeutischer Beratung bei ambulanten dermatologischen Patienten.

    Science.gov (United States)

    Ritter, Viktoria; Fluhr, Joachim W; Schliemann-Willers, Sibylle; Elsner, Peter; Strauß, Bernhard; Stangier, Ulrich

    2016-09-01

    Die Dermatologie ist zunehmend mit Patienten konfrontiert, die unter einer körperdysmorphen Störung (KDS) leiden. Die KDS ist gekennzeichnet durch die übermäßige Beschäftigung mit einem oder mehreren wahrgenommenen Defekten oder Makeln in der äußeren Erscheinung, die für andere nicht oder allenfalls minimal erkennbar sind. Bislang gibt es nur wenige Prävalenzstudien bei KDS im ambulanten dermatologischen Setting. Darüber hinaus wurde die Motivation zu psychotherapeutischer Beratung bei ambulanten dermatologischen Patienten mit körperdysmorphen Symptomen noch nicht systematisch erfasst. Ziel der vorliegenden Studie war daher, die Häufigkeit körperdysmorpher Symptome, die soziale Anpassung sowie die Motivation zu psychotherapeutischer Beratung bei ambulanten dermatologischen Patienten zu untersuchen. 252 ambulante Patienten einer Universitäts-Hautpoliklinik wurden konsekutiv rekrutiert und mittels Dysmorphic Concerns Questionnaire, Soziale Aktivität Selbstbeurteilungs-Skala sowie Veränderungsstadien-Skala untersucht. 7,9 % der unselektierten Gesamtstichprobe erzielten Testresultate, die auf klinisch relevante körperdysmorphe Symptome hinweisen. Patienten mit klinisch relevanten körperdysmorphen Symptomen wiesen eine geringe soziale Anpassung auf. Entgegen den Erwartungen zeigten sie eine hohe Veränderungsmotivation und Bedarf an Psychotherapie. Die Ergebnisse bestätigen die bisherigen Prävalenzraten bei KDS im ambulanten dermatologischen Setting und verdeutlichen die Notwendigkeit psychotherapeutischer Beratungsangebote in der Dermatologie. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  18. Hollywood Megaplex cinema building at Pasching near Linz, Austria; Hollywood Megaplex. Grosskino in Pasching bei Linz

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1996-08-01

    The contribution describes the projecting and construction of a large cinema building at Pasching near Linz. It goes into detail about heating systems, air conditioning systems, and energy conservation measures. (HW) [Deutsch] Es wird berichtet ueber die Planung und die Ausfuehrung der Baumassnahmen Grosskino in Pasching bei Linz. Im Einzelnen: Heizungssysteme; Klimaanlage; Energiesparmassnahmen. (HW)

  19. Precise orbit determination and point positioning using GPS, Glonass, Galileo and BeiDou

    Directory of Open Access Journals (Sweden)

    Tegedor J.

    2014-04-01

    Full Text Available State of the art Precise Point Positioning (PPP is currently based on dual-frequency processing of GPS and Glonass navigation systems. The International GNSS Service (IGS is routinely providing the most accurate orbit and clock products for these constellations, allowing point positioning at centimeter-level accuracy. At the same time, the GNSS landscape is evolving rapidly, with the deployment of new constellations, such as Galileo and BeiDou. The BeiDou constellation currently consists of 14 operational satellites, and the 4 Galileo In-Orbit Validation (IOV satellites are transmitting initial Galileo signals. This paper focuses on the integration of Galileo and BeiDou in PPP, together with GPS and Glonass. Satellite orbits and clocks for all constellations are generated using a network adjustment with observation data collected by the IGS Multi-GNSS Experiment (MGEX, as well as from Fugro proprietary reference station network. The orbit processing strategy is described, and orbit accuracy for Galileo and BeiDou is assessed via orbit overlaps, for different arc lengths. Kinematic post-processed multi-GNSS positioning results are presented. The benefits of multiconstellation PPP are discussed in terms of enhanced availability and positioning accuracy.

  20. Diagnostik der Fatigue bei Multipler Sklerose [Assessment of fatigue in multiple sclerosis

    NARCIS (Netherlands)

    Sander, C.; Voelter, H.U.; Schlake, H.P.; Eling, P.A.T.M.; Hildebrandt, H.

    2017-01-01

    Hintergrund: Fatigue ist eines der häufigsten Symptome bei Multipler Sklerose (MS) und hat deutliche Auswirkungen auf die Lebensqualität sowie die Berufstätigkeit. Die adäquate Messung der erlebten Fatigue ist aber auch heutzutage noch mit erheblicher Unsicherheit behaftet. Ziel der Arbeit: In dem

  1. Zeitlicher Verlauf der avaskulären Nekrose des Hüftkopfes bei Patienten mit Pemphigus vulgaris.

    Science.gov (United States)

    Balighi, Kamran; Daneshpazhooh, Maryam; Aghazadeh, Nessa; Saeidi, Vahide; Shahpouri, Farzam; Hejazi, Pardis; Chams-Davatchi, Cheyda

    2016-10-01

    Pemphigus vulgaris (PV) wird in der Regel mit systemischen Corticosteroiden und Immunsuppressiva behandelt. Avaskuläre Nekrose (AVN) des Hüftkopfes ist eine gut bekannte schwerere Komplikation einer Corticosteroid-Therapie. Die Charakteristika dieser schweren Komplikation bei PV sind nach wie vor unbekannt. Nicht kontrollierte, retrospektive Untersuchung aller PV-bedingten AVN-Fälle, die in einer iranischen Klinik für bullöse Autoimmunerkrankungen zwischen 1985 und 2013 diagnostiziert wurden. Anhand der Krankenakten von 2321 untersuchten PV-Patienten wurden 45 Fälle (1,93 %) von femoraler AVN identifiziert. Dreißig davon waren Männer. Das mittlere Alter bei der Diagnose der AVN betrug 47,4 ± 14,2 Jahre. Der mittlere Zeitraum zwischen der Diagnose des PV und dem Einsetzen der AVN lag bei 25,3 ± 18,3 Monaten. Mit Ausnahme von acht Fällen (17,8 %) setzte die AVN bei der Mehrheit der Patienten innerhalb von drei Jahren nach Diagnose des PV ein. Die mittlere kumulative Dosis von Prednisolon bei Patienten mit AVN betrug 13.115,8 ± 7041,1 mg. Zwischen der Prednisolon-Gesamtdosis und dem Zeitraum bis zum Einsetzen der AVN bestand eine starke Korrelation (p = 0,001). Bei Patienten mit Alendronateinnahme in der Vorgeschichte war dieser Zeitraum signifikant kürzer (p = 0,01). Die AVN ist eine schwere Komplikation einer Corticosteroid-Behandlung bei Patienten mit PV. Sie wird bei 2 % der Patienten beobachtet und tritt vor allem in den ersten drei Behandlungsjahren auf. Bei Patienten, die höhere Dosen von Prednisolon erhalten, setzt die AVN tendenziell früher ein. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  2. Myocardial perfusion imaging with dual energy CT

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); De Cecco, Carlo N. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza”, Rome (Italy); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Spandorfer, Adam; Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States)

    2016-10-15

    Highlights: • Stress dual-energy sCTMPI offers the possibility to directly detect the presence of myocardial perfusion defects. • Stress dual-energy sCTMPI allows differentiating between reversible and fixed myocardial perfusion defects. • The combination of coronary CT angiography and dual-energy sCTMPI can improve the ability of CT to detect hemodynamically relevant coronary artery disease. - Abstract: Dual-energy CT (DECT) enables simultaneous use of two different tube voltages, thus different x-ray absorption characteristics are acquired in the same anatomic location with two different X-ray spectra. The various DECT techniques allow material decomposition and mapping of the iodine distribution within the myocardium. Static dual-energy myocardial perfusion imaging (sCTMPI) using pharmacological stress agents demonstrate myocardial ischemia by single snapshot images of myocardial iodine distribution. sCTMPI gives incremental values to coronary artery stenosis detected on coronary CT angiography (CCTA) by showing consequent reversible or fixed myocardial perfusion defects. The comprehensive acquisition of CCTA and sCTMPI offers extensive morphological and functional evaluation of coronary artery disease. Recent studies have revealed that dual-energy sCTMPI shows promising diagnostic accuracy for the detection of hemodynamically significant coronary artery disease compared to single-photon emission computed tomography, invasive coronary angiography, and cardiac MRI. The aim of this review is to present currently available DECT techniques for static myocardial perfusion imaging and recent clinical applications and ongoing investigations.

  3. Standardized perfusion value of the esophageal carcinoma and its correlation with quantitative CT perfusion parameter values

    Energy Technology Data Exchange (ETDEWEB)

    Djuric-Stefanovic, A., E-mail: avstefan@eunet.rs [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Unit of Digestive Radiology (First University Surgical Clinic), Center of Radiology and MR, Clinical Center of Serbia, Belgrade (Serbia); Saranovic, Dj., E-mail: crvzve4@gmail.com [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Unit of Digestive Radiology (First University Surgical Clinic), Center of Radiology and MR, Clinical Center of Serbia, Belgrade (Serbia); Sobic-Saranovic, D., E-mail: dsobic2@gmail.com [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Center of Nuclear Medicine, Clinical Center of Serbia, Belgrade (Serbia); Masulovic, D., E-mail: draganmasulovic@yahoo.com [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Unit of Digestive Radiology (First University Surgical Clinic), Center of Radiology and MR, Clinical Center of Serbia, Belgrade (Serbia); Artiko, V., E-mail: veraart@beotel.rs [Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Center of Nuclear Medicine, Clinical Center of Serbia, Belgrade (Serbia)

    2015-03-15

    Purpose: Standardized perfusion value (SPV) is a universal indicator of tissue perfusion, normalized to the whole-body perfusion, which was proposed to simplify, unify and allow the interchangeability among the perfusion measurements and comparison between the tumor perfusion and metabolism. The aims of our study were to assess the standardized perfusion value (SPV) of the esophageal carcinoma, and its correlation with quantitative CT perfusion measurements: blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface area product (PS) of the same tumor volume samples, which were obtained by deconvolution-based CT perfusion analysis. Methods: Forty CT perfusion studies of the esophageal cancer were analyzed, using the commercial deconvolution-based CT perfusion software (Perfusion 3.0, GE Healthcare). The SPV of the esophageal tumor and neighboring skeletal muscle were correlated with the corresponding mean tumor and muscle quantitative CT perfusion parameter values, using Spearman's rank correlation coefficient (r{sub S}). Results: Median SPV of the esophageal carcinoma (7.1; range: 2.8–13.4) significantly differed from the SPV of the skeletal muscle (median: 1.0; range: 0.4–2.4), (Z = −5.511, p < 0.001). The cut-off value of the SPV of 2.5 enabled discrimination of esophageal cancer from the skeletal muscle with sensitivity and specificity of 100%. SPV of the esophageal carcinoma significantly correlated with corresponding tumor BF (r{sub S} = 0.484, p = 0.002), BV (r{sub S} = 0.637, p < 0.001) and PS (r{sub S} = 0.432, p = 0.005), and SPV of the skeletal muscle significantly correlated with corresponding muscle BF (r{sub S} = 0.573, p < 0.001), BV (r{sub S} = 0.849, p < 0.001) and PS (r{sub S} = 0.761, p < 0.001). Conclusions: We presented a database of the SPV for the esophageal cancer and proved that SPV of the esophageal neoplasm significantly differs from the SPV of the skeletal muscle, which represented a sample of healthy

  4. Effekte oraler Vitamin-B12-Substitution auf den Stoffwechsel und den Gesundheitsstatus bei Milchkühen

    OpenAIRE

    Obitz, Kristin

    2015-01-01

    Einleitung: Vitamin B12 hat wichtige Funktionen im Energiestoffwechsel sowie bei der Erythropoese. Beide Funktionskreise werden bei Hochleistungskühen besonders beansprucht und können bei Belastungen und ungenügender Vitamin-B12-Versorgung Ausgangspunkt für klinische Störungen werden. Ziele der Untersuchungen: In den vorliegenden Studien wurde der Fragestellung nachgegangen, wie sich die Vitamin-B12-Konzentration im Blutserum von Milchkühen in der Frühlaktation verhält und welche Zusammen...

  5. Treatment of malignant biliary obstructions via the percutaneous approach; Interventionen bei malignen Gallenwegstenosen

    Energy Technology Data Exchange (ETDEWEB)

    Radeleff, B.A.; Lopez-Benitez, R.; Hallscheidt, P.; Grenacher, L.; Libicher, M.; Richter, G.M.; Kauffmann, G.W. [Radiologische Klinik der Ruprecht-Karls-Universitaet Heidelberg (Germany). Abteilung fuer Radiodiagnostik

    2005-11-01

    This paper gives an overview of experience and success of percutaneous transhepatic interventions in malignant biliary obstruction. Even after exhaustion of surgical and endoscopic therapy options, the percutaneously inserted stents provide effective palliation. The palliative treatment of malignant jaundice using a stent is an established procedure in clinical practice, particularly whenever the endoscopic, transpapillary approach is not possible due to high obstructions or previous surgery. The technical success rate is very high (about 95-100%), and the complication rate is about 10-30%. Since the patency rate of stents is higher than that of plastic endoprostheses, their primary use is justified despite higher costs, provided the patients are adequately selected. (orig.) [German] Vorgelegt wird eine Uebersicht ueber den gegenwaertigen Stellenwert radiologischer Interventionen bei malignen Gallenwegstenosen, die nur bei 10-20% der Patienten heilbar sind. Wenn ein endoskopisch transpapillaerer Zugang nicht moeglich ist, z. B. bei hohen Obstruktionen oder nach frueheren Eingriffen, ermoeglichen die perkutane transhepatische Punktion und Implantation von Metallendoprothesen eine gute Palliation. Die perkutane Gallengangdrainage und Stentplatzierung sind fuer den erfahrenen, interventionell taetigen Radiologen wenig kompliziert und mit einer Erfolgsrate von 95-100% dem endoskopischen Vorgehen deutlich ueberlegen. Morbiditaet und Mortalitaet der endoskopischen Verfahren waren in aelteren Arbeiten noch geringer als die der perkutanen Methoden. Aktuellen Studien zufolge sind beide Verfahren gleichwertig, wahrscheinlich aufgrund technischer Verbesserungen der perkutanen Interventionen. Die technische Erfolgsrate bei der Stentapplikation liegt ueber 95%. Mittels perkutaner transhepatischer biliaerer Drainageneinlage (PTCD) eingelegte Metallstents bleiben haeufiger und laenger offen als Plastikstents. Bei entsprechender Lebenserwartung des Patienten ist ihr Einsatz daher

  6. Increasing heel skin perfusion by elevation.

    Science.gov (United States)

    Huber, Jacqueline; Reddy, Raj; Pitham, Tom; Huber, David

    2008-01-01

    To determine the efficacy of elevation in the primary prevention and treatment of pressure ulcers by studying the blood flow in tissue at risk of ulceration. A prospective study was used to compare different preventative devices with an elevating prosthesis. : Wollongong Hospital Wollongong, New South Wales, Australia. Normal subjects and subjects with vasculopathy were tested with their heel resting on a hospital bed, medical-grade lamb's wool, or a viscoelastic gel overlay, with or without the test prosthesis. Skin perfusion was measured throughout using a laser Doppler monitor. A device designed to elevate the heel off the bed and distribute the weight of the leg and foot on the calf. Heel capillary blood perfusion. Perfusion in the heel was significantly greater when elevated than when using the other devices tested. The differences in mean red blood cell flux were significant, with P pressure ulcer prevention and treatment and should be incorporated into health care practice.

  7. Dynamic perfusion patterns in temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Dupont, Patrick; Paesschen, Wim van [KU Leuven/UZ Gasthuisberg, Nuclear Medicine, Medical Imaging Center and Neurology, Leuven (Belgium); Zaknun, John J. [International Atomic Energy Agency (IAEA), Nuclear Medicine Section, Division of Human Health, Wagramer Strasse 5, PO BOX 200, Vienna (Austria); University Hospital of Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Maes, Alex [KU Leuven/UZ Gasthuisberg, Nuclear Medicine, Medical Imaging Center and Neurology, Leuven (Belgium); AZ Groeninge, Nuclear Medicine, Kortrijk (Belgium); Tepmongkol, Supatporn; Locharernkul, Chaichon [Chulalongkorn University, Nuclear Medicine and Neurology, Bangkok (Thailand); Vasquez, Silvia; Carpintiero, Silvina [Fleni Instituto de Investigaciones Neurologicas, Nuclear Medicine, Buenos Aires (Argentina); Bal, C.S. [All India Institute of Medical Sciences, Nuclear Medicine, New Delhi (India); Dondi, Maurizio [International Atomic Energy Agency (IAEA), Nuclear Medicine Section, Division of Human Health, Wagramer Strasse 5, PO BOX 200, Vienna (Austria); Ospedale Maggiore, Nuclear Medicine, Bologna (Italy)

    2009-05-15

    To investigate dynamic ictal perfusion changes during temporal lobe epilepsy (TLE). We investigated 37 patients with TLE by ictal and interictal SPECT. All ictal injections were performed within 60 s of seizure onset. Statistical parametric mapping was used to analyse brain perfusion changes and temporal relationships with injection time and seizure duration as covariates. The analysis revealed significant ictal hyperperfusion in the ipsilateral temporal lobe extending to subcortical regions. Hypoperfusion was observed in large extratemporal areas. There were also significant dynamic changes in several extratemporal regions: ipsilateral orbitofrontal and bilateral superior frontal gyri and the contralateral cerebellum and ipsilateral striatum. The study demonstrated early dynamic perfusion changes in extratemporal regions probably involved in both propagation of epileptic activity and initiation of inhibitory mechanisms. (orig.)

  8. Pulmonary perfusion patterns and pulmonary arterial pressure.

    Science.gov (United States)

    Scott, James A

    2002-08-01

    To use artificial intelligence methods to determine whether quantitative parameters describing the perfusion image can be synthesized to make a reasonable estimate of the pulmonary arterial (PA) pressure measured at angiography. Radionuclide perfusion images were obtained in 120 patients with normal chest radiographs who also underwent angiographic PA pressure measurement within 3 days of the radionuclide study. An artificial neural network (ANN) was constructed from several image parameters describing statistical and boundary characteristics of the perfusion images. With use of a leave-one-out cross-validation technique, this method was used to predict the PA systolic pressure in cases on which the ANN had not been trained. A Pearson correlation coefficient was determined between the predicted and measured PA systolic pressures. ANN predictions correlated with measured pulmonary systolic pressures (r = 0.846, P artificial intelligence methods helps to reveal physiologic information not readily apparent at visual image inspection. Copyright RSNA, 2002

  9. CT-based Techniques for Brain Perfusion.

    Science.gov (United States)

    Krishnan, Pradeep; Murphy, Amanda; Aviv, Richard I

    2017-06-01

    Recent rapid advances in endovascular treatment for acute ischemic stroke highlight the crucial role of neuroimaging especially multimodal computed tomography (CT) including CT perfusion in stroke triage and management decisions. With an increasing focus on changes in cerebral physiology along with time-based matrices in clinical decisions for acute ischemic stroke, CT perfusion provides a rapid and practical modality for assessment and identification of salvageable tissue at risk and infarct core and provides a better understanding of the changes in cerebral physiology. Although there are challenges with the lack of standardization and accuracy of quantitative assessment, CT perfusion is evolving as a cornerstone for imaging-based strategies in the rapid management of acute ischemic stroke.

  10. Optimization of perfusion studies using Atropine

    International Nuclear Information System (INIS)

    Alvarado, A.N.; Valle, V.M.; Montoya, M.J.; Eskenazi, E.S.; Montiel, M.L.; Cueto, C.C.

    2002-01-01

    The studies of myocardial perfusion require an adequate stress; exercise or pharmacological. Every day, more pharmacological studies are performed, specially in some group of patients (women, AMI, etc). There some drugs that are used for this purpose, as adenosine and dobutamine. However, their cost and the lack of availability and infrastructure in our country do not allow there routinely use. We performed dipyridamol as a pharmacological stress, however in some patients there is a doubt regarding if the pharmacological effect was adequate. Atropine is a drug that is frequently used for different purpose and it is well know its tachycardic response. We present and alternative technique, using dipyridamol-atropine as a protocol of stress perfusion study. Our goal was to correlate the standard dipyridamol -thallium perfusion study and the dipyridamol -atropine-perfusion in patients with chronic coronary disease. We evaluated 6 patients (5 males) with stable angina and chronic coronary disease. A standard dipyridamol-thallium study was performed in all of them. Dipyridamole was administered intravenously at a rate of 0.14 mg/kg/min over 6 min for a total of 0.84 mg/kg body weight. Blood pressure, heart rate, EKG and symptoms were monitored before, during and after the pharmacological infusion. Two minutes after the infusion was completed, the radiotracer was injected intravenously. In the next 6 months, without any modification of the clinical situation (symptoms and therapy) a new dipyridamol study was performed, using 1 mg of atropine after the administration of dipyridamol. There were no differences in the collateral effects and we observed and average increase of 30% in the heart rate in relation with the study using dipyridamol alone. The addition of atropine to the standard dipyridamol perfusion study is safe, cheaper and improved the detection of perfusion defects in patients with coronary artery disease

  11. Cerebral perfusion imaging in HIV positive patients

    International Nuclear Information System (INIS)

    Kundley, Kshama; Chowdhury, D.; Lele, V.R.; Lele, R.D.

    1998-01-01

    Full text: Twelve human immunodeficiency virus (HIV) positive patients were studied by SPECT cerebral perfusion imaging 1 hour post injection of 15 mCi of 99m Tc-ECD under ideal conditions with a triple head gamma camera (Prism 3000 X P LEUHR), fanbeam collimators followed by Folstein Mini Mental Status Examination (FMMSE) and AIDS dementia complex (ADC) staging on the same day. All 12 patients were male, in the age range of 23-45 y (mean 31 y). The infected status was diagnosed by ELISA (10 patients) or Western blot (5 patients). The interval between diagnosis and imaging ranged from 1 month - 35 months (mean 15.3 months). Two patients were alcoholic and 2 were smokers. None of them had CNS disorder clinically. ADC staging and FMMSE could be performed in 4 patients. Two patients were normal (stage 0) and 2 were subclinical (stage 0.5) on ADC staging. FMMSE revealed normal or near normal status (mean score 35; maximum score 36). Cerebral perfusion images were interpreted simultaneously by 3 observers blind towards history and examination using semi-quantitative and quantitative methods by consensus. It revealed multiple areas of hypoperfusion, viz. temporal (11 patients (91 %), parietal 10 patients (83%), frontal 9 patients (75%, pre and post central gyrus 7 patients (58%), occipital 6 patients (50%) cingulate gyrus and cerebellum 5 patients (41%) and thalamic in 2 patients (16%). Hyper perfusion in caudate nuclei was noted in 10 patients (83%). The study reveals presence of multiple perfusion abnormalities on cerebral perfusion imaging in HIV positive patients who have normal/near normal mental status suggesting precedence of perfusion abnormality over clinically apparent mental deficit

  12. Meta-Analysis of Stress Myocardial Perfusion Imaging

    Science.gov (United States)

    2017-06-06

    Coronary Disease; Echocardiography; Fractional Flow Reserve, Myocardial; Hemodynamics; Humans; Magnetic Resonance Imaging; Myocardial Perfusion Imaging; Perfusion; Predictive Value of Tests; Single Photon Emission Computed Tomography; Positron Emission Tomography; Multidetector Computed Tomography; Echocardiography, Stress; Coronary Angiography

  13. A novel microthermal probe for the measurement of perfusion

    Science.gov (United States)

    Yi, Ming; Kausik, Aditya; Podhajsky, Ronald J.; Mahajan, Roop L.

    2009-02-01

    Using micro-fabrication techniques a micro thermal probe has been developed in our laboratory to measure the thermal conductivity of biological tissues. This paper presents our latest experimental results which demonstrate the usefulness of the micro thermal probe in mapping the complicated perfusion field inside biological tissues. A perfused pig liver model has been constructed to simulate in vivo conditions. The portal vein and hepatic artery of a porcine liver were intubated and connected to a perfusion circuit. Saline water was perfused through the liver driven by a peristaltic pump. By varying the pumping rate of the perfused model, we measured the effective thermal conductivity at different perfusion rates in different locations. The results show that the effective thermal conductivity varies with the square root of the perfusion rate. Also, by rotating the micro probes, we observed a strong directional dependence of the effective thermal conductivity, revealing that perfusion is not a scalar but a vector field.

  14. Improved visualization of delayed perfusion in lung MRI

    International Nuclear Information System (INIS)

    Risse, Frank; Eichinger, Monika; Kauczor, Hans-Ulrich; Semmler, Wolfhard; Puderbach, Michael

    2011-01-01

    Introduction: The investigation of pulmonary perfusion by three-dimensional (3D) dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was proposed recently. Subtraction images are generated for clinical evaluation, but temporal information is lost and perfusion defects might therefore be masked in this process. The aim of this study is to demonstrate a simple analysis strategy and classification for 3D-DCE-MRI perfusion datasets in the lung without omitting the temporal information. Materials and methods: Pulmonary perfusion measurements were performed in patients with different lung diseases using a 1.5 T MR-scanner with a time-resolved 3D-GRE pulse sequence. 25 3D-volumes were acquired after iv-injection of 0.1 mmol/kg KG Gadolinium-DTPA. Three parameters were determined for each pixel: (1) peak enhancement S n,max normalized to the arterial input function to detect regions of reduced perfusion; (2) time between arterial peak enhancement in the large pulmonary artery and tissue peak enhancement τ to visualize regions with delayed bolus onset; and (3) ratio R = S n,max /τ was calculated to visualize impaired perfusion, irrespectively of whether related to reduced or delayed perfusion. Results: A manual selection of peak perfusion images is not required. Five different types of perfusion can be found: (1) normal perfusion; (2) delayed non-reduced perfusion; (3) reduced non-delayed perfusion; (4) reduced and delayed perfusion; and (5) no perfusion. Types II and IV could not be seen in subtraction images since the temporal information is necessary for this purpose. Conclusions: The analysis strategy in this study allows for a simple and observer-independent visualization and classification of impaired perfusion in dynamic contrast-enhanced pulmonary perfusion MRI by using the temporal information of the datasets.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-11-01

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

  16. CT angiography and CT perfusion in acute ischemic stroke

    NARCIS (Netherlands)

    Seeters, T. van

    2016-01-01

    CT angiography and CT perfusion are used in patients with acute ischemic stroke for diagnostic purposes and to select patients for treatment. In this thesis, the reproducibility of CT angiography and CT perfusion is examined, the additional value of CT angiography and CT perfusion for stroke outcome

  17. Automatic Detection of Myocardial Boundaries in MR Cardio Perfusion Images

    NARCIS (Netherlands)

    Spreeuwers, Luuk; Breeuwer, Marcel

    2001-01-01

    Cardiovascular diseases often result in reduced blood perfusion of the myocardium (MC). Recent advances in MR allow fast recordingof contrast enhanced myocardial perfusion scans. For perfusion analysis the myocardial boundaries must be traced. Currently this is done manually. In this paper a method

  18. Increased sinusoidal volume and solute extraction during retrograde liver perfusion

    International Nuclear Information System (INIS)

    Bass, N.M.; Manning, J.A.; Weisiger, R.A.

    1989-01-01

    Retrograde isolated liver perfusion has been used to probe acinar functional heterogeneity, but the hemodynamic effects of backward flow have not been characterized. In this study, extraction of a long-chain fatty acid derivative, 12-N-methyl-7-nitrobenzo-2-oxa-1,3-diazol-amino stearate (12-NBDS), was greater during retrograde than during anterograde perfusion of isolated rat liver. To determine whether hemodynamic differences between anterograde and retrograde perfused livers could account for this finding, the hepatic extracellular space was measured for both directions of flow by means of [ 14 C]sucrose washout during perfusion as well as by direct measurement of [ 14 C]sucrose entrapped during perfusion. A three- to fourfold enlargement of the total hepatic extracellular space was found during retrograde perfusion by both approaches. Examination of perfusion-fixed livers by light microscopy and morphometry revealed that marked distension of the sinusoids occurred during retrograde perfusion and that this accounts for the observed increase in the [ 14 C]sucrose space. These findings support the hypothesis that maximum resistance to perfusate flow in the isolated perfused rat liver is located at the presinusoidal level. In addition, increased transit time of perfusate through the liver and greater sinusoidal surface area resulting from sinusoidal distension may account for the higher extraction of 12-NBDS and possibly other compounds by retrograde perfused liver

  19. An alternative method for neonatal cerebro-myocardial perfusion

    Science.gov (United States)

    Luciani, Giovanni Battista; De Rita, Fabrizio; Faggian, Giuseppe; Mazzucco, Alessandro

    2012-01-01

    Several techniques have already been described for selective cerebral perfusion during repair of aortic arch pathology in children. One method combining cerebral with myocardial perfusion has also been proposed. A novel technique is reported here for selective and independent cerebro-myocardial perfusion for neonatal and infant arch surgery. Technical aspects and potential advantages are discussed. PMID:22307393

  20. Der zivilisationswortschatz bei den Serben und Kroaten im 19. jahrhundert: Am beispiel einiger begriffe aus wirtschaft und bankwesen

    Directory of Open Access Journals (Sweden)

    Neveklovski Gerhard

    2008-01-01

    Full Text Available (nemački Die angeführten Belege aus den Sachgebieten Wirtschaft, Handel Bankwesen stellen eine Auswahl aus dem umfangreichen Projekt 'Gesellschaft und Wirtschaft' der Balkankommission der Österreichischen Akademie der Wissenschaften dar. Sie zeigen deutlich, wie bei den Serben und Kroaten bei der Schaffung eines den Zeiterfordernissen angepassten Wortschatzes auf verschiedene Traditionen zurückgegriffen wird, und dass diese Traditionen ihre Kontinuität bis heute besitzen. Bei den Serben bleiben viel eher internationale Entlehnungen erhalten als bei den Kroaten, die eher einheimisches Wortmaterial vorziehen. Im einzelnen werden die Begriffe Aktie Bankrott, Darlehen, Kapital, Kasse, Pacht, Ware, Zinsen mit ihren Ableitungen behandelt. Die Beispiele sind Beiträge zur Wortgeschichte, die Angaben im großen Akademiewörterbuch (ARj ergänzen oder korrigieren und einen Überblick über die Techniken der Entstehung neuer Wörter vermitteln sollen.

  1. A direct comparison of the sensitivity of CT and MR cardiac perfusion using a myocardial perfusion phantom.

    OpenAIRE

    Otton, James; Morton, Geraint; Schuster, Andreas; Bigalke, Boris; Marano, Riccardo; Olivotti, Luca; Nagel, Eike; Chiribiri, Amedeo

    2013-01-01

    BACKGROUND: Direct comparison of CT and magnetic resonance (MR) perfusion techniques has been limited and in vivo assessment is affected by physiological variability, timing of image acquisition, and parameter selection. OBJECTIVE: We precisely compared high-resolution k-t SENSE MR cardiac perfusion at 3 T with single-phase CT perfusion (CTP) under identical imaging conditions. METHODS: We used a customized MR imaging and CT compatible dynamic myocardial perfusion phantom to represe...

  2. Stellenwert der Leberelastometrie (Acoustic Radiaion Force Impulse) während antiviraler Tripeltherapie bei chronischer Hepatitis C

    OpenAIRE

    Rösch, Lara

    2017-01-01

    Hintergrund und Ziele: In einer prospektiven Studie wurden Änderungen der Leberelastizität bei Patienten mit chronischer Hepatitis C unter antiviraler Therapie und deren potentielle prognostische Aussagekraft bezüglich eines Therapieansprechens untersucht. Methodik: Im Zeitraum von 09/2012 bis 08/2014 wurde prospektiv bei 23 Patienten zu definierten Zeitpunkten (Therapiebeginn, Therapieende, 12 Wochen nach Therapie) die Elastizität der Leber bestimmt. Hierfür wurde eine ultraschall-basie...

  3. MRA in inflammatory disorders of the central nervous system; Magnetresonanz-Angiographie bei entzuendlichen Hirnerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Felber, S. [Universitaetsklinik Innsbruck (Austria). Klinische Abt. fuer Radiologie II; Auer, A. [Universitaetsklinik Innsbruck (Austria). Inst. fuer Magnetresonanztomographie und Spektroskopie; Schmutzhard, E. [Universitaetsklinik fuer Neurologie, Innsbruck (Austria)

    2000-11-01

    In this review, we discuss the diagnostic potential of time of flight (TOF) MRA and contrast enhanced (CE) MRA in inflammatory disorders of the meninges and the brain. Cerebrovascular complications are frequently observed during infectious meningoencepalitis. 3D TOF-MRA and CE-MRA are complementary for the detection of basal intracranial artery stenosis and septic cerebral vein and sinus thrombosis due to secondary vasculitis. MRA reveals stenosis and occlusion as indirect signs of vasculitis, whereas MRI shows the inflammation of the brain and meninges and occasionally the vessel wall, together with the ischemic or hemorrhagic complication. In case of septic emboli MRA can detect peripheral occlusions and 'mycotic' aneurysms. For the diagnosis of noninfectious vasculitides of the intracranial vessels, high resolution 3D TOF-MRA is superior to CE-MRA for the detection of multiloculated segmental stenoses. However, there are presently no prospective studies on the sensitivity and specificity of MRA for these indications. Therefore, only positive MRA results can directly influence clinical management. In case of normal MRA, confirmation by catheder angiography may still be required. (orig.) [German] Diese Uebersicht behandelt die Moeglichkeiten der Time of flight MRA (TOF-MRA) und der kontrastmittelunterstuetzten MRA (KM-MRA) bei zerebral entzuendlichen Erkrankungen. Vaskulaere Komplikationen bei entzuendlichen Erkrankungen des Gehirns und der Meningen sind haeufig. Bei der infektioesen Meningitis kann die MRA eine sekundaere Vaskulitis des Circulus arteriosus Willisii und seiner Aeste, aber auch eine septische Hirnvenen- und Sinusthrombose nachweisen. Die TOF-MRA und KM-MRA liefern dabei komplementaere Informationen. In der gleichen Untersuchung kann eine entzuendliche Infiltration der Meningen bildgebend diagnostiziert werden. Bei der haematogen Herdenzephalitis im Rahmen einer Sepsis oder Endokarditis ist die MRA zur diagnose embolischer

  4. Magnetic resonance spectroscopy in schizophrenia. Possibilities and limitations; Magnetresonanzspektroskopie bei Schizophrenie. Moeglichkeiten und Grenzen

    Energy Technology Data Exchange (ETDEWEB)

    Wobrock, T. [Universitaetsklinikum des Saarlandes, Homburg/Saar (Germany). Klinik fuer Psychiatrie und Psychotherapie; Universitaetsklinikum des Saarlandes, Klinik fuer Psychiatrie und Psychotherapie, Homburg/Saar (Germany); Scherk, H.; Falkai, P. [Universitaetsklinikum des Saarlandes, Homburg/Saar (Germany). Klinik fuer Psychiatrie und Psychotherapie

    2005-02-01

    Magnetic resonance spectroscopy is a noninvasive investigative technique for in vivo detection of biochemical changes in neuropsychiatric disorders for which especially proton ({sup 1}H-MRS) and phosphorus ({sup 31}P-MRS) magnetic resonance spectroscopy have been used. In this review we explain the principles of MRS and summarize the studies in schizophrenia. A systematic literature review was carried out for {sup 1}H-MRS studies investigating schizophrenic patients compared to controls. The inconsistent results in the cited studies may be due to different study population, specific neuroimaging technique, and selected brain regions. Frequent findings are decreased PME and increased PDE concentrations ({sup 31}P-MRS) linked to altered metabolism of membrane phospholipids and decreased N-acetylaspartate (NAA) or NAA/choline ratio ({sup 1}H-MRS) linked to neuronal damage in frontal (DLPFC) or temporal regions in patients with schizophrenia. These results contribute to the disturbed frontotemporal-thalamic network assumed in schizophrenia and are supported by additional functional neuroimaging, MRI morphometry, and neuropsychological evaluation. The combination of the described investigative techniques with MRS in follow-up studies may provide more specific clues for understanding the pathogenesis and disease course in schizophrenia. (orig.) [German] Die Magnetresonanzspektroskopie (MRS) stellt ein nichtinvasives Verfahren dar, mit dem in vivo biochemische Veraenderungen spezifischer Hirnregionen bei verschiedenen psychiatrischen Erkrankungen untersucht werden koennen. Dabei werden insbesondere die Protonenmagnetresonanzspektroskopie ({sup 1}H-MRS) sowie die Phosphormagnetresonanzspektroskopie ({sup 31}P-MRS) verwendet. In der vorliegenden Uebersichtsarbeit werden die methodischen Grundlagen erlaeutert sowie die Befundlage bei der Schizophrenie referiert. Fuer die Darstellung der Studien zur {sup 1}H-MRS bei schizophrenen Patienten im Vergleich zu einer Kontrollgruppe

  5. Urothelkarzinome des oberen Harntraktes: Retrospektive Studie zu Diagnostik, Tumorcharakteristika und Therapie bei 28 Patienten

    Directory of Open Access Journals (Sweden)

    Maruschke M

    2005-01-01

    Full Text Available Urotheliale Tumoren des oberen Harntraktes sind selten. Sie repräsentieren nur etwa 5 % aller Urothelkarzinome. In der vorliegenden Studie wurden Tumorparameter, demographische Faktoren, diagnostische und therapeutische Maßnahmen sowie die Follow-up-Daten von 28 Patienen mit Urothelkarzinomen des oberen Harntraktes analysiert und retrospektiv bezüglich der Effektivität diagnostischer Methoden (Urinzytologie, Ausscheidungsurogramm, retrogrades Ureteropyelogramm, CT, Endoskopie sowie hinsichtlich des therapeutischen Vorgehens ausgewertet. Zusätzlich fanden das histopathologische Tumorstaging, das Grading der Tumoren sowie die Rezidivhäufigkeit und das Patientenüberleben Berücksichtigung. Die Hauptsymptome waren eine Hämaturie in 60,0 % und Flankenschmerzen in 39,0 %. Eine Urinzytologie wurde bei 17 Patienten (60,7 % durchgeführt, mit richtig-positivem Ergebnis in 8 Fällen (47,0 %. Folgende radiologische Untersuchungsmethoden kamen zur Anwendung: 21 Patienten 75,0 % erhielten ein Ausscheidungsurogramm (AUG, 15 Patienten (53,5 % ein retrogrades Ureteropyelogramm (RUP und 25 Patienten (89,3 % ein CT. Eine Tumoridentifikation gelang mit AUG bei 14 Patienten (66,6 %, mit RUP bei 14 Patienten (93,3 % und mit CT bei 20 Patienten (80,0 %. Eine Ureterorenoskopie wurde bei 13 Patienten (46,4 % durchgeführt, davon mit richtig-positivem Ergebnis in 10 Fällen (77,0 %. Eine chirurgische Therapie erhielten alle 28 Patienten; in 24 Fällen erfolgte eine radikale Nephroureterektomie (86 %. Das mittlere Follow-up betrug 56,6 Monate (Range: 2–97 Monate. 8 Patienten (28,5 % entwickelten ein rezidivierendes Urothelkarzinom in der Harnblase nach durchschnittlich 23,1 Monaten. 4 Patienten (14,28 % verstarben im Tumorprogreß nach durchschnittlich 12,25 Monaten (Range: 2–23 Monate. Bei Patienten mit Hämaturie und/oder Flankenschmerzen muß das Vorliegen eines Urotheltumors des oberen Harntraktes differentialdiagnostisch in Betracht gezogen werden. Die

  6. Study of lung perfusion in colagenosis

    International Nuclear Information System (INIS)

    Macedo de Carvalho, A.C.; Calegaro, J.U.M.

    1982-01-01

    The lung involvement in the various types of colagenosis has been widely described in the literature. However, the study of lung perfusion utilizing radionuclides has been only mentioned in a few papers. With the intention of ascertaining the importance of the lung perfusion scanning in colagenosis, ten cases were studied, seven of which were females and three males, with the following pathologies: 4 rheumatoid arthritis, 4 systemic lupus eritematosous, 1 scleroderma and 1 scleroderma plus dermatomyositis. The ages of the patients varied from 20 to 73 years, and the duration of the disease from 1 month to 39 years. The lung scanning showed perfusion defects in 100% of the cases, not related with the type of colagenosis, duration of the disease, sex or age. On the other hand, the X rays study showed alterations in only 2 patients (20% of the cases). The ventilatory and respiratory functions were tested on 7 patients showing alteration (mixed pattern with predominance of the restrictive factor) in only one (14.3%), while the other patients were normal (85.7%). The importance of the lung perfusion scanning study in all patients with collagen vascular diseases is emphasized. (author) [es

  7. Hypothermic machine perfusion in kidney transplantation

    NARCIS (Netherlands)

    De Deken, Julie; Kocabayoglu, Peri; Moers, Cyril

    Purpose of reviewThis article summarizes novel developments in hypothermic machine perfusion (HMP) as an organ preservation modality for kidneys recovered from deceased donors.Recent findingsHMP has undergone a renaissance in recent years. This renewed interest has arisen parallel to a shift in

  8. Methodology for ventilation/perfusion SPECT

    DEFF Research Database (Denmark)

    Bajc, Marika; Neilly, Brian; Miniati, Massimo

    2010-01-01

    in all projections as well as in rotating volume images based upon maximum intensity projections. Probabilistic interpretation of V/Q SPECT should be replaced by a holistic interpretation strategy on the basis of all relevant information about the patient and all ventilation/perfusion patterns. PE...

  9. Nonrigid registration of myocardial perfusion MRI

    DEFF Research Database (Denmark)

    Ólafsdóttir, Hildur

    2005-01-01

    This paper describes a fully automatic registration of 10 multi-slice myocardial perfusion magnetic resonance image sequences. The registration of these sequences is crucial for the clinical interpretation, which currently is subjected to manual labour. The approach used in this study is a nonrig...

  10. Quality assessment of a placental perfusion protocol

    DEFF Research Database (Denmark)

    Mathiesen, Line; Mose, Tina; Mørck, Thit Juul

    2010-01-01

    Validation of in vitro test systems using the modular approach with steps addressing reliability and relevance is an important aim when developing in vitro tests in e.g. reproductive toxicology. The ex vivo human placental perfusion system may be used for such validation, here presenting...

  11. Computed Tomography (CT) Perfusion in Abdominal Cancer

    DEFF Research Database (Denmark)

    Hansen, Martin Lundsgaard; Norling, Rikke; Lauridsen, Carsten

    2013-01-01

    for assessment of vascularity. CT perfusion has also been used for tumor characterization, staging of disease, response evaluation of newer drugs targeted towards angiogenesis and as a method for early detection of recurrence after radiation and embolization. There are several software solutions available...

  12. Methodology for ventilation/perfusion SPECT

    DEFF Research Database (Denmark)

    Bajc, Marika; Neilly, Brian; Miniati, Massimo

    2010-01-01

    Ventilation/perfusion single-photon emission computed tomography (V/Q SPECT) is the scintigraphic technique of choice for the diagnosis of pulmonary embolism and many other disorders that affect lung function. Data from recent ventilation studies show that the theoretic advantages of Technegas ov...

  13. Study of lung perfusion in colagenosis

    Energy Technology Data Exchange (ETDEWEB)

    Macedo de Carvalho, A.C.; Calegaro, J.U.M. (Fundacao Hospitalar do Distrito Federal, Distrito Federal (Brazil). Unidade de Medicina Nuclear)

    1982-07-01

    The lung involvement in the various types of colagenosis has been widely described in the literature. However, the study of lung perfusion utilizing radionuclides has been only mentioned in a few papers. With the intention of ascertaining the importance of the lung perfusion scanning in colagenosis, ten cases were studied, seven of which were females and three males, with the following pathologies: 4 rheumatoid arthritis, 4 systemic lupus eritematosous, 1 scleroderma and 1 scleroderma plus dermatomyositis. The ages of the patients varied from 20 to 73 years, and the duration of the disease from 1 month to 39 years. The lung scanning showed perfusion defects in 100% of the cases, not related with the type of colagenosis, duration of the disease, sex or age. On the other hand, the X rays study showed alterations in only 2 patients (20% of the cases). The ventilatory and respiratory functions were tested on 7 patients showing alteration (mixed pattern with predominance of the restrictive factor) in only one (14.3%), while the other patients were normal (85.7%). The importance of the lung perfusion scanning study in all patients with collagen vascular diseases is emphasized.

  14. Nuclear cardiology: Myocardial perfusion and function

    International Nuclear Information System (INIS)

    Seldin, D.W.

    1991-01-01

    Myocardial perfusion studies continue to be a major focus of research, with new investigations of the relationship of exercise-redistribution thallium imaging to diagnosis, prognosis, and case management. The redistribution phenomenon, which seemed to be fairly well understood a few years ago, is now recognized to be much more complex than originally thought, and various strategies have been proposed to clarify the meaning of persistent defects. Pharmacologic intervention with dipyridamole and adenosine has become available as an alternative to exercise, and comparisons with exercise imaging and catheterization results have been described. Thallium itself is no longer the sole single-photon perfusion radiopharmaceutical; two new technetium agents are now widely available. In addition to perfusion studies, advances in the study of ventricular function have been made, including reports of studies performed in conjunction with technetium perfusion studies, new insights into cardiac physiology, and the prognostic and case-management information that function studies provide. Finally, work has continued with monoclonal antibodies for the identification of areas of myocyte necrosis. 41 references

  15. Volume perfusion CT imaging of cerebral vasospasm: diagnostic performance of different perfusion maps

    Energy Technology Data Exchange (ETDEWEB)

    Othman, Ahmed E. [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); Eberhard Karls University Tuebingen, University Hospital Tuebingen, Department for Diagnostic and Interventional Radiology, Tuebingen (Germany); Afat, Saif; Nikoubashman, Omid; Mueller, Marguerite; Wiesmann, Martin; Brockmann, Carolin [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); Schubert, Gerrit Alexander [RWTH Aachen University, Department of Neurosurgery, Aachen (Germany); Bier, Georg [Eberhard Karls University Tuebingen, University Hospital Tuebingen, Department for Diagnostic and Interventional Neuroradiology, Tuebingen (Germany); Brockmann, Marc A. [RWTH Aachen University, Department of Diagnostic and Interventional Neuroradiology, Aachen (Germany); University Hospital Mainz, Department of Neuroradiology, Mainz (Germany)

    2016-08-15

    In this study, we aimed to evaluate the diagnostic performance of different volume perfusion CT (VPCT) maps regarding the detection of cerebral vasospasm compared to angiographic findings. Forty-one datasets of 26 patients (57.5 ± 10.8 years, 18 F) with subarachnoid hemorrhage and suspected cerebral vasospasm, who underwent VPCT and angiography within 6 h, were included. Two neuroradiologists independently evaluated the presence and severity of vasospasm on perfusion maps on a 3-point Likert scale (0 - no vasospasm, 1 - vasospasm affecting <50 %, 2 - vasospasm affecting >50 % of vascular territory). A third neuroradiologist independently assessed angiography for the presence and severity of vasospasm on a 3-point Likert scale (0 - no vasospasm, 1 - vasospasm affecting < 50 %, 2 - vasospasm affecting > 50 % of vessel diameter). Perfusion maps of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to drain (TTD) were evaluated regarding diagnostic accuracy for cerebral vasospasm with angiography as reference standard. Correlation analysis of vasospasm severity on perfusion maps and angiographic images was performed. Furthermore, inter-reader agreement was assessed regarding findings on perfusion maps. Diagnostic accuracy for TTD and MTT was significantly higher than for all other perfusion maps (TTD, AUC = 0.832; MTT, AUC = 0.791; p < 0.001). TTD revealed higher sensitivity than MTT (p = 0.007). The severity of vasospasm on TTD maps showed significantly higher correlation levels with angiography than all other perfusion maps (p ≤ 0.048). Inter-reader agreement was (almost) perfect for all perfusion maps (kappa ≥ 0.927). The results of this study indicate that TTD maps have the highest sensitivity for the detection of cerebral vasospasm and highest correlation with angiography regarding the severity of vasospasm. (orig.)

  16. Basic consideration of diffusion/perfusion imaging

    International Nuclear Information System (INIS)

    Tamagawa, Yoichi; Kimura, Hirohiko; Matsuda, Tsuyoshi; Kawamura, Yasutaka; Nakatsugawa, Shigekazu; Ishii, Yasushi; Sakuma, Hajime; Tsukamoto, Tetsuji.

    1990-01-01

    In magnetic resonance imaging (MRI), microscopic motion of biological system such as molecular diffusion of water and microcirculation of blood in the capillary network (perfusion) has been proposed to cause signal attenuation as an intravoxel incoherent motion (IVIM). Quantitative imaging of the IVIM phenomenon was attempted to generate from a set of spin-echo (SE) sequences with or without sensitization by motion probing gradient (MPG). The IVIM imaging is characterized by a parameter, apparent diffusion coefficient (ADC), which is an integration of both the diffusion and the perfusion factor on voxel-by-voxel basis. Hard ware was adjusted to avoid image artifact mainly produced by eddy current. Feasibility of the method was tested using bottle phantom filled with water at different temperature and acetone, and the calculated ADC values of these media corresponded well with accepted values of diffusion. The method was then applied to biological system to investigate mutual participation of diffusion/perfusion on the ADC value. The result of tumor model born on nude mouse suggested considerable participation of perfusion factor which immediately disappeared after sacrificing the animal. Meanwhile, lower value of sacrificed tissue without microcirculation was suggested to have some restriction of diffusion factor by biological tissue. To substantiate the restriction effect on the diffusion, a series of observation have made on a fiber phantom, stalk of celory with botanical fibers and human brain with nerve fibers, in applying unidirectional MPG along the course of these banch of fiber system. The directional restriction effect of diffusion along the course of fiber (diffusion anisotrophy) was clearly visualized as directional change of ADC value. The present method for tissue characterization by diffusion/perfusion on microscopic level will provide a new insight for evaluation of functional derangement in human brain and other organs. (author)

  17. Ventilation-perfusion distribution in normal subjects.

    Science.gov (United States)

    Beck, Kenneth C; Johnson, Bruce D; Olson, Thomas P; Wilson, Theodore A

    2012-09-01

    Functional values of LogSD of the ventilation distribution (σ(V)) have been reported previously, but functional values of LogSD of the perfusion distribution (σ(q)) and the coefficient of correlation between ventilation and perfusion (ρ) have not been measured in humans. Here, we report values for σ(V), σ(q), and ρ obtained from wash-in data for three gases, helium and two soluble gases, acetylene and dimethyl ether. Normal subjects inspired gas containing the test gases, and the concentrations of the gases at end-expiration during the first 10 breaths were measured with the subjects at rest and at increasing levels of exercise. The regional distribution of ventilation and perfusion was described by a bivariate log-normal distribution with parameters σ(V), σ(q), and ρ, and these parameters were evaluated by matching the values of expired gas concentrations calculated for this distribution to the measured values. Values of cardiac output and LogSD ventilation/perfusion (Va/Q) were obtained. At rest, σ(q) is high (1.08 ± 0.12). With the onset of ventilation, σ(q) decreases to 0.85 ± 0.09 but remains higher than σ(V) (0.43 ± 0.09) at all exercise levels. Rho increases to 0.87 ± 0.07, and the value of LogSD Va/Q for light and moderate exercise is primarily the result of the difference between the magnitudes of σ(q) and σ(V). With known values for the parameters, the bivariate distribution describes the comprehensive distribution of ventilation and perfusion that underlies the distribution of the Va/Q ratio.

  18. Ventilation and perfusion display in a single image

    International Nuclear Information System (INIS)

    Lima, J.J.P. de; Botelho, M.F.R.; Pereira, A.M.S.; Rafael, J.A.S.; Pinto, A.J.; Marques, M.A.T.; Pereira, M.C.; Baganha, M.F.; Godinho, F.

    1991-01-01

    A new method of ventilation and perfusion display onto a single image is presented. From the data on regions of interest of the lungs, three-dimensional histograms are created, containing as parameters X and Y for the position of the pixels, Z for the perfusion and colour for local ventilation. The perfusion value is supplied by sets of curves having Z proportional to the local perfusion count rate. Ventilation modulates colour. Four perspective views of the histogram are simultaneously displayed to allow visualization of the entire organ. Information about the normal ranges for both ventilation and perfusion is also provided in the histograms. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-04-15

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

  20. C-Arm Conebeam CT Perfusion Imaging in the Angiographic Suite: A Comparison with Multidetector CT Perfusion Imaging.

    Science.gov (United States)

    Niu, K; Yang, P; Wu, Y; Struffert, T; Doerfler, A; Schafer, S; Royalty, K; Strother, C; Chen, G-H

    2016-07-01

    Perfusion imaging in the angiography suite may provide a way to reduce time from stroke onset to endovascular revascularization of patients with large-vessel occlusion. Our purpose was to compare conebeam CT perfusion with multidetector CT perfusion. Data from 7 subjects with both multidetector CT perfusion and conebeam CT perfusion were retrospectively processed and analyzed. Two algorithms were used to enhance temporal resolution and temporal sampling density and reduce the noise of conebeam CT data before generating perfusion maps. Two readers performed qualitative image-quality evaluation on maps by using a 5-point scale. ROIs indicating CBF/CBV abnormalities were drawn. Quantitative analyses were performed by using the Sørensen-Dice coefficients to quantify the similarity of abnormalities. A noninferiority hypothesis was tested to compare conebeam CT perfusion against multidetector CT perfusion. Average image-quality scores for multidetector CT perfusion and conebeam CT perfusion images were 2.4 and 2.3, respectively. The average confidence score in diagnosis was 1.4 for both multidetector CT and conebeam CT; the average confidence scores for the presence of a CBV/CBF mismatch were 1.7 (κ = 0.50) and 1.5 (κ = 0.64). For multidetector CT perfusion and conebeam CT perfusion maps, the average scores of confidence in making treatment decisions were 1.4 (κ = 0.79) and 1.3 (κ = 0.90). The area under the visual grading characteristic for the above 4 qualitative quality scores showed an average area under visual grading characteristic of 0.50, with 95% confidence level cover centered at the mean for both readers. The Sørensen-Dice coefficient for CBF maps was 0.81, and for CBV maps, 0.55. After postprocessing methods were applied to enhance image quality for conebeam CT perfusion maps, the conebeam CT perfusion maps were not inferior to those generated from multidetector CT perfusion. © 2016 by American Journal of Neuroradiology.

  1. FAIR true-FISP perfusion imaging of the thyroid gland.

    Science.gov (United States)

    Schraml, Christina; Boss, Andreas; Martirosian, Petros; Schwenzer, Nina F; Claussen, Claus D; Schick, Fritz

    2007-07-01

    To evaluate the feasibility of quantitative perfusion MRI of the thyroid gland using an arterial spin labeling (ASL) method. An ASL technique with flow-sensitive alternating inversion-recovery (FAIR) spin preparation and a true fast imaging in the steady state (TrueFISP) signal readout strategy was implemented on a 1.5T whole-body unit. Anatomical and perfusion imaging of the thyroid gland was performed in eight healthy volunteers and one patient with functioning adenoma. Quantitative perfusion maps were calculated using the extended Bloch equations. In all subjects the perfusion images showed diagnostic image quality. The mean examination time was 24 minutes for multiplanar perfusion imaging of the entire thyroid gland. Individual perfusion values ranged between 341 +/- 91 and 640 +/- 90 mL/100 g/minute, with a mean perfusion of 461 +/- 90 mL/100 g/minute. The functioning adenoma showed markedly reduced perfusion compared to normal thyroidal parenchyma. No perfusion was noticeable inside four detected thyroid cysts. Quantitative ASL perfusion imaging of the thyroid gland using a FAIR-TrueFISP sequence leads to perfusion maps that may provide important information for assessing thyroid gland pathologies and monitoring therapeutic treatment. Copyright 2007 Wiley-Liss, Inc.

  2. Auswirkungen des Urin-pH auf das Ballonvolumen bei Dauerkathetern

    Directory of Open Access Journals (Sweden)

    Pannek J

    2007-01-01

    Full Text Available Einleitung: Eine häufige Komplikation der transurethralen oder suprapubischen Dauerkatheterversorgung ist die Dislokation durch eine insuffiziente Katheterblockung. Die Auswirkungen des Urin-pH auf das Ballonvolumen sind dabei bisher nicht untersucht. Methodik: In einer In-vitro-Studie wurden Dauerkatheter aus Silikon und Latex mit entweder 10%iger Glyzerinlösung oder mit 0,9%iger NaCl-Lösung geblockt und 14 Tage bei verschiedenen pH-Werten in künstlichem Urin gelagert. Nach diesem Zeitraum wurde die rückgewonnene Flüssigkeit aus dem Katheterballon gemessen. Ergebnisse: Bei allen Katheterballons wurde eine Reduktion des Ballonvolumens von maximal 20 % festgestellt. Weder das verwendete Füllmedium noch das Kathetermaterial hatte signifikante Auswirkungen auf das Ausmaß der Volumenänderung. Schlußfolgerung: Die Änderung des Urin-pH führt nicht zu Volumenverschiebungen im Katheterballon.

  3. The Design of Compass/BeiDou Navigation Satellite Terminal for Migrant Bird Research

    Directory of Open Access Journals (Sweden)

    Yaohui Li

    2014-01-01

    Full Text Available A terminal of Compass Navigation Satellite System (CNSS, which can not only support BeiDou-1 and BeiDou-2 but also support Global Positioning System (GPS, is designed to research the activities of the migrant birds, with our novel design of a multiband antenna. By a high-density integration, this terminal is designed with a compact size and light weight. When the terminal is assembled to a whooper swan, its flying trace is recorded by the CNSS, which is in agreement with that of GPS. The flying route map based on the CNSS is useful to check the situation and habit of the migrant bird, which is important for animal protection and bird flu outbreak prediction.

  4. Pulmonary ventilation and perfusion abnormalities and ventilation perfusion imbalance in children with pulmonary atresia or extreme tetralogy of Fallot

    International Nuclear Information System (INIS)

    Dowdle, S.C.; Human, D.G.; Mann, M.D.

    1990-01-01

    Xenon-133 lung ventilation and perfusion scans were done preoperatively after cardiac catheterization and cineangiocardiography in 19 children; 6 had pulmonary atresia with an intact ventricular septum and hypoplastic right ventricle, 4 pulmonary atresia with associated complex univentricular heart, and 9 extreme Tetralogy of Fallot. The four patients with discrepancies in the sizes of the left and right pulmonary arteries on angiography had marked asymmetry of pulmonary perfusion and ventilation-perfusion imbalance on scintigraphy. Similar degrees of asymmetry and imbalance were present in 6 of the 15 children with equal-size pulmonary vessels. Asymmetry of pulmonary perfusion and ventilation-perfusion imbalance were associated with a poor prognosis

  5. Pulmonary ventilation and perfusion abnormalities and ventilation perfusion imbalance in children with pulmonary atresia or extreme tetralogy of Fallot

    Energy Technology Data Exchange (ETDEWEB)

    Dowdle, S.C.; Human, D.G.; Mann, M.D. (Univ. of Cape Town (South Africa))

    1990-08-01

    Xenon-133 lung ventilation and perfusion scans were done preoperatively after cardiac catheterization and cineangiocardiography in 19 children; 6 had pulmonary atresia with an intact ventricular septum and hypoplastic right ventricle, 4 pulmonary atresia with associated complex univentricular heart, and 9 extreme Tetralogy of Fallot. The four patients with discrepancies in the sizes of the left and right pulmonary arteries on angiography had marked asymmetry of pulmonary perfusion and ventilation-perfusion imbalance on scintigraphy. Similar degrees of asymmetry and imbalance were present in 6 of the 15 children with equal-size pulmonary vessels. Asymmetry of pulmonary perfusion and ventilation-perfusion imbalance were associated with a poor prognosis.

  6. Erkrankungen des Traumaspektrums bei ruandischen Waisen des Genozids : Epidemiologie und Behandlung

    OpenAIRE

    Schaal, Susanne

    2006-01-01

    Im Jahre 1994 kamen in Ruanda innerhalb von 100 Tagen fast eine Million Menschen auf brutalste Weise ums Leben. Vorliegende Studie untersuchte die Traumakonfrontation und mentalen Gesundheitseffekte dieses staatlich organisierten Genozids bei ruandischen Waisen (n = 118) 11 Jahre nach dem Völkermord. Die Stichprobe setzte sich aus Vollwaisen zusammen, die entweder in kindergeführten Haushalten oder in Waisenheimen der Hauptstadt Kigali lebten. Risikofaktoren wurden analysiert und die Wirksamk...

  7. Comparison of Ultra-Rapid Orbit Prediction Strategies for GPS, GLONASS, Galileo and BeiDou

    OpenAIRE

    Tao Geng; Peng Zhang; Wei Wang; Xin Xie

    2018-01-01

    Currently, ultra-rapid orbits play an important role in the high-speed development of global navigation satellite system (GNSS) real-time applications. This contribution focuses on the impact of the fitting arc length of observed orbits and solar radiation pressure (SRP) on the orbit prediction performance for GPS, GLONASS, Galileo and BeiDou. One full year’s precise ephemerides during 2015 were used as fitted observed orbits and then as references to be compared with predicted orbits, togeth...

  8. Zur Rolle der Familie bei Essanfällen im Kindes- und Jugendalter

    OpenAIRE

    Tetzlaff, Anne; Hilbert, Anja

    2016-01-01

    Fragestellung: Während der Einfluss der Familie bei Anorexia Nervosa und Bulimia Nervosa im Kindes- und Jugendalter gut belegt ist und bereits mehrmals in Übersichtsarbeiten zusammengefasst wurde, liegen derzeit wenige Befunde zum Zusammenhang zu Essanfällen ohne kompensatorische Verhaltensweisen vor. Ziel dieser systematischen Übersichtsarbeit ist es daher, familiäre Einflussfaktoren auf die Entstehung und Aufrechterhaltung von Essanfällen zu beschreiben. Methodik: Eine systematische Date...

  9. Functional MR urography in patients with renal transplants; Funktionelle MR-Urographie bei Patienten mit Nierentransplantaten

    Energy Technology Data Exchange (ETDEWEB)

    Knopp, M.V. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Doersam, J. [Heidelberg Univ. (Germany). Abt. Urologie und Poliklinik; Oesingmann, N. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Piesche, S. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Hawighorst, H. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Wiesel, M. [Heidelberg Univ. (Germany). Abt. Urologie und Poliklinik; Schad, L.R. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Kaick, G. van [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie

    1997-03-01

    Purpose: To assess the value of functional magnetic resonance urography for the noninvasive postoperative evaluation of renal transplants. Methods: A saturation inversion projection sequence allows the selective imaging of strongly T1 weighted signal from the MR contrast agent. A coronal slab leads to images comparable to conventional urography which can be acquired as a sequence with four images per minute. Results: 15 patients with urologic questionable findings after renal transplantation were studied. FMRU revealed in 6 patients normal findings, in 6 moderate dilatation of the renal pelvis without any urodynamic relevant obstruction. 3 pathologic findings, ureteral leak, ureteropelvic-junction obstruction and ureteral stenosis were diagnosed and consequently surgically treated. The imaging quality in all studies was diagnostic and urologically relevant. Conclusion: FMRU can be used as a noninvasive technique for the assessment of renal transplant in cases with suspicion of complication in the excretory system. (orig.) [Deutsch] Fragestellung: Laesst sich die funktionelle Magnetresonanzurographie (FMRU) zur nichtinvasiven Diagnostik im postoperativen Verlauf von Nierentransplantaten einsetzen? Methodik: Mit Hilfe einer Saturation-Inversion-Projektionstechnik kann eine selektive Darstellung der durch das Kontrastmittel stark verkuerzten T1-gewichteten Signalanteile erreicht werden. Durch koronare Schichtfuehrung entstehen Bilder vergleichbar mit einer konventionellen Urographie, die als Sequenz von 4 Bildern pro Minute aufgenommen werden. Ergebnisse: 15 Patienten mit urologisch abklaerungsbeduerftigen Befunden nach Nierentransplantation wurden untersucht. Mit der FMRU konnte bei 6 Patienten ein unauffaelliger Befund, bei 6 eine diskrete Dilatation des Nierenbeckenkelchsystems ohne urodynamisch relevante Abflussbehinderung nachgewiesen werden, jeweils eine Harnleiterleckage, eine Harnleitermuendungsstenose und eine Harnleiterabgangsenge wurden diagnostiziert und

  10. Kognitiv-behaviorale Psychotherapie bei Jugendlichen mit Essstörungen

    OpenAIRE

    Ruhl, Uwe; Jacobi, Corinna

    2005-01-01

    Anorexia nervosa (AN), Bulimia nervosa (BN) und Binge Eating Störungen (BED) werden unter dem Begriff Essstörungen zusammengefasst. Insbesondere die AN stellt im Jugendalter aufgrund des typischen Beginns in diesem Altersbereich eine häufige Erkrankung mit häufig ungünstigen Verlauf (Steinhausen 2002) dar. Die psychischen, sozialen und körperlichen Folgen sind gravierend. Die Therapieforschung zeigt, dass die kognitiv-behaviorale Behandlung (CBT) bei BN, BN und BED im Erwachsenena...

  11. Ambulante und stationäre Krisenintervention bei Kindern und Jugendlichen

    OpenAIRE

    Deutschmann-Barth, Katharina

    2002-01-01

    Einleitung: In der vorliegenden Studie werden, aufbauend auf zwei frühere Studien aus der Abteilung für Psychiatrie und Psychotherapie im Kindes- und Jugendalter der Universitätsklinik Tübingen, stationäre und ambulante Kriseninterventionen unter verschiedenen Blickwinkeln miteinander verglichen. Ein Schwerpunkt der Arbeit liegt in der Darstellung des Vorgehens bei ambulanten und stationären Kriseninterventionen , sowie des jeweiligen Aufwandes der für Therapie und Betreuung der Krisenpatient...

  12. Vitex-agnus-castus-Extrakt (Ze 440 zur Symptombehandlung bei Frauen mit menstruellen Zyklusstörungen

    Directory of Open Access Journals (Sweden)

    Eltbogen R

    2015-01-01

    Full Text Available Ziel: Diese nichtinterventionelle Beobachtungsstudie (NIS wurde von Schweizer Gynäkologen und Allgemeinmedizinern im Rahmen der üblichen ärztlichen Grundversorgung durchgeführt. Das Ziel der NIS war es, die Wirksamkeit und Sicherheit von Vitex-agnus-castus-(VAC Extrakt (Ze 440: premens, Zeller Medical AG, Romanshorn, Schweiz bei Frauen, die unter menstruellen Zyklusstörungen wie Polymenorrhö, Oligomenorrhö oder Amenorrhö litten, zu untersuchen. Methode: Insgesamt 211 Patientinnen nahmen an dieser NIS teil. Symptome, die mit menstruellen Zyklusstörungen („menstrual cycle irregularities“ [MCIs] und der Menstruationsblutung in Verbindung stehen, wurden bei einer Erstuntersuchung („baseline visit“ [BV] und einer Kontrolluntersuchung („follow-up visit“ [FV] nach Behandlung mit VAC-Extrakt über einen Zeitraum von 3 aufeinanderfolgenden Menstruationszyklen beurteilt. Ergebnisse: Der Anteil der Patientinnen, bei denen eine Beschwerdefreiheit oder eine Besserung der MCIs (insgesamt und spezifischer Beschwerdebilder wie Polymenorrhö, Oligomenorrhö und Amenorrhö erzielt werden konnte, lag bei der FV bei 79–85 %. Bei Symptomen im Zusammenhang mit der Menstruationsblutung wie Dysmenorrhö, Zwischenblutungen, Hypermenorrhö, Menometrorrhagie, Ovulationsblutung, präoder postmenstrueller Blutung betrug der Anteil der Patientinnen, bei denen ein Rückgang oder eine Besserung festgestellt wurde, bei der FV zwischen 60 und 88 %. Von 53 Patientinnen, die bei der BV von einem unerfüllten Kinderwunsch berichteten, wurden 12 Frauen (23 % während der Behandlung mit VAC-Extrakt schwanger. Bei der FV waren 91 % der Ärzte und 92 % der Patientinnen mit den erzielten Behandlungsergebnissen „zufrieden“ oder „sehr zufrieden“ und 80 % der Patientinnen bestätigten, dass sie gerne mit der Behandlung mit VAC-Extrakt fortfahren wollen. Fazit: Diese Beobachtungsstudie im Bereich der ärztlichen Grundversorgung ergab, dass die Behandlung mit VAC

  13. First experiences with MR mammography in aftercare following plastic surgery of cancer of the breast; Erste Erfahrungen mit der MR-Mammographie in der Nachsorge bei lappenunterstuetzter operativer Behandlung des Mammakarzinoms

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, B. [Radiologische Klinik, Evangelisches Krankenhaus Duesseldorf (Germany); Audretsch, W. [Abt. fuer Senologie, Frauenklinik des Krankenhauses Gerresheim, Kliniken der Landeshauptstadt Duesseldorf (Germany); Rezai, M. [Abt. fuer Senologie, Frauenklinik des Krankenhauses Gerresheim, Kliniken der Landeshauptstadt Duesseldorf (Germany); Achten, C. [Radiologische Klinik, Evangelisches Krankenhaus Duesseldorf (Germany); Zocholl, G. [Radiologische Klinik, Evangelisches Krankenhaus Duesseldorf (Germany)

    1996-04-01

    To demonstrate typical MR mammographic findings after plastic surgery of breast cancer. Postoperative (7-38 months, median 13) MR mammographic examinations of 25 patients operated for breast cancer (11 latissimus dorsiflaps (LAT)), 14 rectus abdominis myocutaneous-flaps (TRAM) were reevaluated. The examinations were performed with a breast coil at 1 T. The sequences applied were a fat-suppressed 2-D turbo IR-sequence protonweighted and a T{sub 1}-weighted FLASH 3-D sequence as dynamic series. Scars between the myocutaneous flap and the remaining breast tissue always appeared in form of a ligament or septum. Signal and perfusion characteristics of scar tissue and muscle stalk in this investigation were clearly different from fat necrosis was found and rectified by biopsy. MR mammography is a very valuable diagnostic method for postoperative evaluation of myocutaneous flap-based therapy of breast cancer. (orig.) [Deutsch] Erfassung typischer MR-mammographischer Befunde bei lappenunterstuetzter operativer Behandlung des Mammakarzinoms. Die postoperativen (7-38 Monate, Median 13 Monate) MR-Mammographien von 25 (11 Latissimus-dorsi-Plastiken (LAT)), 14 Rectus-abdominis-Plastiken (TRAM) wegen eines Mammakarzinoms lappenunterstuetzt operierten Patientinnen (Alter 34-67 Jahre, Median 48 Jahre) wurden retrospektiv ausgewertet. Die Untersuchungen erfolgten mit einer bimammaeren Brustspule 1 T. Als Untersuchungssequenz dienten eine Protonen-gewichtete, fettsupprimierte 2-D-Turbo-IR-Sequenz und eine T{sub 1}-gewichtete FLASH-3-D-Sequenz als dynamische Untersuchung. Das Narbengewebe zwischen Lappenplastik und Restdruesengewebe stellte sich immer band- oder septenfoermig dar. Signal- und Anreicherungsverhalten der Narben boten in unserem Kollektiv kein differential-diagnostisches Problem bei der Abgrenzung zum Tumorgewebe. Ein Tumorrezidiv und eine Fettgewebsnekrose wurden durch die MR-Mammographie erfasst und histologisch verifiziert. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-01

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

  15. An accurate Kriging-based regional ionospheric model using combined GPS/BeiDou observations

    Science.gov (United States)

    Abdelazeem, Mohamed; Çelik, Rahmi N.; El-Rabbany, Ahmed

    2018-01-01

    In this study, we propose a regional ionospheric model (RIM) based on both of the GPS-only and the combined GPS/BeiDou observations for single-frequency precise point positioning (SF-PPP) users in Europe. GPS/BeiDou observations from 16 reference stations are processed in the zero-difference mode. A least-squares algorithm is developed to determine the vertical total electron content (VTEC) bi-linear function parameters for a 15-minute time interval. The Kriging interpolation method is used to estimate the VTEC values at a 1 ° × 1 ° grid. The resulting RIMs are validated for PPP applications using GNSS observations from another set of stations. The SF-PPP accuracy and convergence time obtained through the proposed RIMs are computed and compared with those obtained through the international GNSS service global ionospheric maps (IGS-GIM). The results show that the RIMs speed up the convergence time and enhance the overall positioning accuracy in comparison with the IGS-GIM model, particularly the combined GPS/BeiDou-based model.

  16. Neuere Untersuchungen zur Prädiktion von EEG-Signalen bei Epilepsie

    Directory of Open Access Journals (Sweden)

    C. Niederhöfer

    2007-06-01

    Full Text Available Seit einigen Jahren ist die Analyse von EEG-Signalen bei Epilepsie Gegenstand zahlreicher wissenschaftlicher Arbeiten; Zielvorstellung ist dabei die Entwicklung von Verfahren zur Erkennung eines möglichen Voranfallszustandes. Im Vordergrund steht beispielsweise die Approximation einer so genannten effektiven Korrelationsdimension, die Bestimmung der maximalen Lyapunov-Exponenten, Detektionsverfahren für Muster bei Zellularen Nichtlinearen Netzwerken, die Bestimmung der mittleren Phasenkohärenz und Verfahren zur nichtlinearen Prädiktion von EEG-Signalen. Trotz umfangreicher Bemühungen kann bis heute eine Erkennung von Anfallsvorboten mit einer Sensitivität und Spezifität, die eine automatisierte Anfallsvorhersage ermöglichen würde, noch nicht durchgeführt werden. In diesem Beitrag werden neue Ergebnisse zur Prädiktion von EEG-Signalen bei Epilepsie vorgestellt. Dabei werden Signale, welche mittels intrakranieller electrocorticographischer (ECoG und stereoelectroencephalographischer (SEEG Ableitungen registriert wurden, segmentweise analysiert. Unter der Annahme, dass sich Änderungen des Systems ,,Gehirn" als Änderungen im Prädiktor, d.h. in seinen Systemparametern widerspiegeln, könnte eine nähere Betrachtung der Prädiktoreigenschaften zu einer Erkennung von Anfallsvorboten führen.

  17. A Fast and High-precision Orientation Algorithm for BeiDou Based on Dimensionality Reduction

    Directory of Open Access Journals (Sweden)

    ZHAO Jiaojiao

    2015-05-01

    Full Text Available A fast and high-precision orientation algorithm for BeiDou is proposed by deeply analyzing the constellation characteristics of BeiDou and GEO satellites features.With the advantage of good east-west geometry, the baseline vector candidate values were solved by the GEO satellites observations combined with the dimensionality reduction theory at first.Then, we use the ambiguity function to judge the values in order to obtain the optical baseline vector and get the wide lane integer ambiguities. On this basis, the B1 ambiguities were solved. Finally, the high-precision orientation was estimated by the determinating B1 ambiguities. This new algorithm not only can improve the ill-condition of traditional algorithm, but also can reduce the ambiguity search region to a great extent, thus calculating the integer ambiguities in a single-epoch.The algorithm is simulated by the actual BeiDou ephemeris and the result shows that the method is efficient and fast for orientation. It is capable of very high single-epoch success rate(99.31% and accurate attitude angle (the standard deviation of pitch and heading is respectively 0.07°and 0.13°in a real time and dynamic environment.

  18. Normas e práticas contábeis aplicadas ao Terceiro Setor

    Directory of Open Access Journals (Sweden)

    Franciane Santos Silva

    2009-10-01

    Full Text Available Observa-se um grande crescimento de organizações não-governamentais, que não visam ao lucro e produzem serviços para o atendimento das demandas da coletividade. Constitui um setor específico, para além do Estado - primeiro setor - e do setor privado - segundo setor -, que se convencionou chamar terceiro setor. O governo brasileiro tem buscado mecanismos para normatizar as ações desse setor, especialmente no que diz respeito ao repasse de recursos públicos. Neste contexto, a contabilidade passou a ser requerida pelos vários organismos governamentais e não-governamentais, para o fornecimento de demonstrações contábeis e outras informações por ela geradas. No entanto, verifica-se que, apesar da existência de alguns normativos contábeis, tais como as normas editadas pelo Conselho Federal de Contabilidade (NBC T 10.4, 10.16, 10.18 e 10.19, e a obrigatoriedade da observação dos princípios fundamentais de contabilidade, no existe uma uniformidade nos procedimentos contábeis adotados pelo terceiro setor.

  19. Hepatic perfusion changes in an experimental model of acute pancreatitis: Evaluation by perfusion CT

    Energy Technology Data Exchange (ETDEWEB)

    Tutcu, Semra [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey); Serter, Selim, E-mail: serterselim@gmail.co [Department of Radiology, Celal Bayar University, School of Medicine, Manisa (Turkey); Kaya, Yavuz; Kara, Eray [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey); Nese, Nalan [Department of Pathology, Celal Bayar University, School of Medicine, Manisa (Turkey); Pekindil, Goekhan [Department of Radiology, Celal Bayar University, School of Medicine, Manisa (Turkey); Coskun, Teoman [Department of Surgery, Celal Bayar University, School of Medicine, Manisa (Turkey)

    2010-08-15

    Purpose: It is known that acute pancreatitis may cause secondary changes in several organs. Liver is one of these involved organs. In different experimental studies hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT. Materials and methods: Forty Sprague-Dawley rats of both genders with average weights of 250 g were used. Rats were randomized into two groups. Twenty rats were in control group and 20 in acute pancreatitis group. pCT was performed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student's t test was used for statistical analyses. Results: In pCT we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p < 0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance. Conclusion: The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue. Systemic mediators seem to be effective as well as local inflammatory changes in perfusion changes.

  20. Patient satisfaction with coronary CT angiography, myocardial CT perfusion, myocardial perfusion MRI, SPECT myocardial perfusion imaging and conventional coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Feger, S.; Rief, M.; Zimmermann, E.; Richter, F.; Roehle, R. [Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Humboldt-Universitaet zu Berlin, Berlin (Germany); Dewey, M. [Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Humboldt-Universitaet zu Berlin, Berlin (Germany); Institut fuer Radiologie, Berlin (Germany); Schoenenberger, E. [Medizinische Hochschule Hannover, Department of Medicine, Hannover (Germany)

    2015-07-15

    To evaluate patient acceptance of noninvasive imaging tests for detection of coronary artery disease (CAD), including single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI), stress perfusion magnetic resonance imaging (MRI), coronary CT angiography (CTA) in combination with CT myocardial stress perfusion (CTP), and conventional coronary angiography (CCA). Intraindividual comparison of perception of 48 patients from the CORE320 multicentre multinational study who underwent rest and stress SPECT-MPI with a technetium-based tracer, combined CTA and CTP (both with contrast agent, CTP with adenosine), MRI, and CCA. The analysis was performed by using a validated questionnaire. Patients had significantly more concern prior to CCA than before CTA/CTP (p < 0.001). CTA/CTP was also rated as more comfortable than SPECT-MPI (p = 0.001). Overall satisfaction with CT was superior to that of MRI (p = 0.007). More patients preferred CT (46 %; p < 0.001) as a future diagnostic test. Regarding combined CTA/CTP, CTP was characterised by higher pain levels and an increased frequency of angina pectoris during the examination (p < 0.001). Subgroup analysis showed a higher degree of pain during SPECT-MPI with adenosine stress compared to physical exercise (p = 0.016). All noninvasive cardiac imaging tests are well accepted by patients, with CT being the preferred examination. (orig.)

  1. Hat die Ejakulation in Medium einen Effekt auf die Schwangerschaftsrate bei der Intrazytoplasmatischen Spermieninjektion bei Patienten mit schwerer Oligoasthenoteratozoospermie? Ergebnisse einer retrospektiven Analyse

    Directory of Open Access Journals (Sweden)

    Zollner K-P

    2002-01-01

    Full Text Available Durch die Gewinnung einer Samenprobe in Medium erhöht sich der Anteil der antikörperfreien Spermatozoen in Samenproben mit antikörperbehafteten Spermien und erhöht somit die Fertilisationsrate in vitro. Das Ziel dieser Studie war es zu untersuchen, ob sich dieser Verdünnungseffekt auch günstig auf Ejakulate mit einem Oligoasthenoterato-zoospermie (OAT-Syndrom auswirkt, in denen oft eine große Anzahl an Bakterien und Zelldetritus den Spermien anhaftet. Die Zugabe von Medium vor der Verflüssigung könnte das Anhaften von Bakterien und Detritus an der Spermienoberfläche verhindern und somit zu besseren Befruchtungschancen führen. 173 Patienten, die in einem Probespermiogramm oder einem früheren IVF-Zyklus ein schweres OAT-Syndrom zeigten, wurden in diese retrospektive Studie eingeschlossen. Alle Patienten durchliefen 1997 und 1998 das ICSI-ET (Intrazytoplasmatische Spermieninjektion und Embryotransfer Programm an der Universität Würzburg. 118 Patienten gewannen ihre Samenprobe in leere, sterile Gefäße (Gruppe A und 55 Patienten ejakulierten in 20 ml Hepes gepuffertes Ham's F-10-Medium, das mit 10 % HSA (humanes Serumalbumin versetzt war (Gruppe B. Das Alter der Patientinnen und der Ehemänner, die Ejakulatparameter und die Anzahl der transferierten Embryonen war in beiden Gruppen vergleichbar. Alle Ejakulate wurden gemäß WHO-Kriterien klassifiziert. Nach Gewinnung der Samenprobe in Medium wurde das Ejakulat der Gruppe B für 30 min inkubiert, anschließend zentrifugiert und mit einer Swim-up-Technik aufbereitet. Die Ejakulate der Gruppe A wurden ebenfalls mit einer Swim-up-Technik präpariert. Bei den 173 ICSI-Zyklen konnten durchschnittlich 9,3 Eizellen gewonnen werden. Die mediane Fertilisationsrate (FR lag bei 83,3 % und unterschied sich in den Gruppen A (FR = 87,5 % und B (FR = 77,8 % nicht signifikant. Es wurden im Mittel 2,7 Embryonen transferiert. 27 von 118 Patientinnen der Gruppe A konzipierten, was zu einer klinischen

  2. Effects of spin-orbit coupling on laser cooling of BeI and MgI.

    Science.gov (United States)

    Wan, Mingjie; Huang, Duohui; Shao, Juxiang; Yu, You; Li, Song; Li, Yuanyuan

    2015-10-28

    We present the ab initio study of spin-orbit coupling effects on laser cooling of BeI and MgI molecules. Potential energy curves for the X(2)Σ(+)(1/2), A(2)Π(1/2,3/2), and 2(2)Π(3/2,1/2) states are calculated using multi-reference configuration interaction method plus Davidson corrections. Spectroscopic parameters of BeI and MgI are in excellent agreement with available experimental and theoretical values. The A(2)Π(3/2) state of MgI is a repulsive state. It is an unsuitable scheme for the A(2)Π(3/2)(υ')← X(2)Σ(+)(1/2) (υ″) transition for laser cooling of MgI. Highly diagonally distributed Franck-Condon factors f00 for the A(2)Π(1/2,3/2) (υ' = 0) ← X(2)Σ(+)(1/2) (υ″ = 0) transitions and suitable radiative lifetimes τ for the A(2)Π(1/2,3/2) (υ' = 0) of BeI and MgI are obtained. Three laser wavelength drives are required for the A(2)Π(1/2,3/2)(υ')←X(2)Σ(+)(1/2) (υ″) transitions of BeI and MgI. The proposed cooling wavelengths of BeI and MgI are both in the violet region. The results imply the feasibility of laser cooling of BeI and MgI, and that laser cooling of BeI is more possible.

  3. Adjuvant chemo- and radiotherapy in gastrointestinal tumors; Adjuvante Chemo- und Strahlentherapie bei gastrointestinalen Tumoren

    Energy Technology Data Exchange (ETDEWEB)

    Sendler, A. [Technische Univ. Muenchen (Germany). Chirurgische Klinik und Poliklinik; Feldmann, H.J. [Technische Univ. Muenchen (Germany). Inst. und Poliklinik fuer Strahlentherapie und Radiologische Onkologie; Fink, U. [Technische Univ. Muenchen (Germany). Chirurgische Klinik und Poliklinik; Molls, M. [Technische Univ. Muenchen (Germany). Inst. und Poliklinik fuer Strahlentherapie und Radiologische Onkologie; Siewert, J.R. [Technische Univ. Muenchen (Germany). Chirurgische Klinik und Poliklinik

    1995-04-21

    In modern surgical oncology, adjuvant therapies are important complementary strategies. In local advanced carcinomas of the gastrointestinal tract, 5-year survival data are still disappointing despite standardized surgery. In this context, it has to be differentiated between adjuvant therapy following complete tumor exstirpation (so-called UICC R{sub 0} resection) and additive therapies following incomplete tumor resections (UICC R{sub 1} or R{sub 2} resection). Modalities in the adjuvant setting are chemotherapy, radiotherapy or the combined radio-/chemotherapy. In esophageal and gastric cancer there is up to now no benefit of postoperative adjuvant therapy. In pancreatic cancer, there are studies indicating a benefit of combined radio-/chemotherapy after complete tumor resection. A standard adjuvant chemotherapeutic treatment is proven in colon cancer stage III (Dukes C) with levamisole and 5-FU. Completely resected rectal carcinoma should be treated postoperatively with combined radio-/chemotherapy. In the common clinical or practical setting, adjuvant therapy is indicated only in locally advanced gastrointestinal tumors following R{sub 0} resection. Postoperative therapy following incomplete tumor resection has its reason only in a palliative intention. (orig.) [Deutsch] Adjuvante Therapiestrategien sind wichtige flankierende Massnahmen der modernen onkologischen Chirurgie, da u.a. die 5-Jahres-Ueberlebensquoten bei lokal fortgeschrittenen Tumoren des Gastrointestinaltraktes nach wie vor unbefriedingend sind. Dabei muss grundsaetzlich zwischen adjuvanten Behandlungen nach kompletter Tumorexstirpation (UICC-R{sub 0}-Resektion) und der additiven Therapie nach palliativer Resektion (UICC-R{sub 1}- oder -R{sub 2}-Resektion) unterschieden werden. Als Modalitaeten kommen Chemotherapie, Strahlentherapie und ihre Kombination in Frage. Bei Oesophagus- und Magenkarzinomen kann derzeit keine gueltige Empfehlung zur adjuvanten Therapie gegeben werden. Die Radio

  4. Furosemide urogram in patients with neobladder; Das Diureseurogramm bei Patienten mit Harnblasenersatz

    Energy Technology Data Exchange (ETDEWEB)

    Merkle, E.M. [Univ. Ulm (Germany). Abt. Radiologie; Aschoff, A.J. [Univ. Ulm (Germany). Abt. Radiologie; Bachor, R. [Univ. Ulm (Germany). Abt. fuer Urologie; Vogel, J. [Univ. Ulm (Germany). Abt. Radiologie; Merk, J. [Univ. Ulm (Germany). Abt. Radiologie; Brambs, H.J. [Univ. Ulm (Germany). Abt. Radiologie

    1996-11-01

    Purpose: To differentiate between urodynamically relevant obstruction and functionally unimportant dilation of the upper urinary tract in patients with neobladder using a modified furosemide urogram. Method: An excretory urogram with furosemide loading was carried out in 19 patients with neobladder and sonographically and urographically confirmed dilation of the upper urinary tract. Once strong contrasting of the renal pelves and calyces has been achieved, 20 mg of furosemide were applied and late radiographs were obtained at 15 min and 30 min, respectively. An obstruction was defined as increasing dilation of the renal pelves and calices during forced diuresis and lack of washout effect of the contrast medium. Results: In 32 cases, the renoureteral unit (RUU) was dilated on ultrasound. Of these, 25 RUU`s showed good emptyness of contrast medium upon stimulation of diuresis, six RUU`s returned a borderline findings, while one RUU was found to exhibit a decompensated anastomotic stenosis, which was dilated. Two further patients with bordeline findings were later treated surgically due to their pain symptoms. No patient required further preoperative diagnostic procedures. Conclusions: The modified furosemide urogram represents a cost-effective diagnostic orientation strategy in patients with neobladder and dilated renal pelves and calyses and is both well-tolerated by patients and meets with broad acceptance from the urologic staff. (orig.) [Deutsch] Ziel: Differenzierung zwischen urodynamisch relevanter Obstruktion und funktionell bedeutungsloser Dilatation des oberen Harntraktes bei Patienten mit Harnblasenersatz durch ein modifiziertes Diureseurogramm. Methodik: Bei 19 Patienten mit Harnableitung und sonographisch sowie urographisch nachgewiesener Erweiterung des oberen Harntraktes wurde ein Ausscheidungsurogramm mit Furosemidbelastung durchgefuehrt. Bei kraeftiger Kontrastierung des erweiterten Nierenbeckenkelchsystems (NBKS) wurden 20 mg Furosemid appliziert und

  5. Perfusion lung scintigraphy in primary pulmonary hypertension

    International Nuclear Information System (INIS)

    Ogawa, Y.; Hayashida, K.; Uehara, T.; Shimonagata, T.; Nishimura, T.; Osaka Univ., Suita

    1993-01-01

    15 cases of primary pulmonary hypertension were classified into two groups by patterns of perfusion lung scintigraphy. Perfusion scintigrams showed multiple, small, ill-defined defects (mottled + ve) pattern in eight cases, and the remaining seven cases had a normal (mottled - ve) pattern. The mean pulmonary arterial pressure in patients with a mottled pattern (54 ± 10 mmHg) was higher than in those with a normal pattern (42 ± 9 mmHg, p < 0.05). There were no significant differences between the two groups in right ventricular ejection fraction, partial pressures of oxygen in the arterial blood or alveolo-arterial oxygen difference. All the patients with a mottled pattern died within 2 years following the lung scintigraphy. There was a significant difference in the survival curves between the two groups. (author)

  6. Perfusion lung scintigraphy in primary pulmonary hypertension

    International Nuclear Information System (INIS)

    Ogawa, Yoji; Nishimura, Tsunehiko; Kumita, Shin-ichirou; Hayashida, Kohei; Uehara, Toshiisa; Shimonagata, Tsuyoshi; Ohno, Akira

    1991-01-01

    Fifteen cases with primary pulmonary hypertension (PPH) were classified into two groups by using the perfusion lung scan pattern. Eight cases had multiple, small, ill-defined defects (mottled pattern), and remaining seven cases had no mottled pattern. These two groups were compared with mean pulmonary arterial pressure (mean PAP), right ventricular ejection fraction (RVEF), blood gas at room air (PaO 2 ), and alveolar-arterial O 2 difference (A-aDo 2 ). The cases with mottled pattern showed a significant increase in mean PAP. There were no significant differences in RVEF, PaO 2 , and A-aDo 2 , between the groups. The survival rate of the patients with mottled pattern was significantly lower than that without mottled pattern (p<0.05). We concluded that perfusion lung scan is very useful for evaluation of the prognosis in primary pulmonary hypertension. (author)

  7. Quantitative aspects of myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Vogel, R.A.

    1980-01-01

    Myocardial perfusion measurements have traditionally been performed in a quantitative fashion using application of the Sapirstein, Fick, Kety-Schmidt, or compartmental analysis principles. Although global myocardial blood flow measurements have not proven clinically useful, regional determinations have substantially advanced our understanding of and ability to detect myocardial ischemia. With the introduction of thallium-201, such studies have become widely available, although these have generally undergone qualitative evaluation. Using computer-digitized data, several methods for the quantification of myocardial perfusion images have been introduced. These include orthogonal and polar coordinate systems and anatomically oriented region of interest segmentation. Statistical ranges of normal and time-activity analyses have been applied to these data, resulting in objective and reproducible means of data evaluation

  8. Non-contrast MRI perfusion angiosome in diabetic feet

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Jie [Cardiovascular Imaging Lab, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Hastings, Mary K.; Mueller, Michael J. [Washington University School of Medicine, The Program in Physical Therapy, St. Louis, MO (United States); Muccigross, David; Hildebolt, Charles F. [Washington University School of Medicine, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Fan, Zhaoyang [Cedars-Sinai Medical Center, Biomedical Imaging Research Institute, Los Angeles, CA (United States); Gao, Fabao [West China Hospital, Sichuan University, Department of Radiology, Chengdu (China); Curci, John [Washington University School of Medicine, The Department of Surgery, St. Louis, MO (United States)

    2015-01-15

    The purpose of this study is to develop a non-contrast magnetic resonance imaging (MRI) approach to evaluate skeletal muscle perfusion in the diabetic foot based on the concept of angiosomes of the foot. Five healthy volunteers and five participants with diabetes (HbA1c = 7.2 ± 1.8 %) without a history of peripheral artery disease were examined. The non-contrast perfusion measurements were performed during a toe flexion challenge. Absolute perfusion maps were created and two regions (medial and lateral) on the maps were segmented based on angiosomes. Regional difference in the perfusion of foot muscle was readily visualized in the MRI perfusion angiosomes during the challenge. In the participants with diabetes, the perfusion during toe flexion challenge was significantly lower than in healthy volunteers (P < 0.01). The average perfusion for the medial plantar region of the right foot was lower in subjects with diabetes (38 ± 9 ml/min/100 g) than in healthy subjects (93 ± 33 ml/min/100 g). Non-contrast MRI perfusion angiosome maps demonstrate the feasibility of determining regional perfusion in foot muscles during toe challenge and may facilitate evaluation of muscle perfusion in diabetic feet. (orig.)

  9. Dynamic CT perfusion measurement in a cardiac phantom.

    Science.gov (United States)

    Ziemer, Benjamin P; Hubbard, Logan; Lipinski, Jerry; Molloi, Sabee

    2015-10-01

    Widespread clinical implementation of dynamic CT myocardial perfusion has been hampered by its limited accuracy and high radiation dose. The purpose of this study was to evaluate the accuracy and radiation dose reduction of a dynamic CT myocardial perfusion technique based on first pass analysis (FPA). To test the FPA technique, a pulsatile pump was used to generate known perfusion rates in a range of 0.96-2.49 mL/min/g. All the known perfusion rates were determined using an ultrasonic flow probe and the known mass of the perfusion volume. FPA and maximum slope model (MSM) perfusion rates were measured using volume scans acquired from a 320-slice CT scanner, and then compared to the known perfusion rates. The measured perfusion using FPA (P(FPA)), with two volume scans, and the maximum slope model (P(MSM)) were related to known perfusion (P(K)) by P(FPA) = 0.91P(K) + 0.06 (r = 0.98) and P(MSM) = 0.25P(K) - 0.02 (r = 0.96), respectively. The standard error of estimate for the FPA technique, using two volume scans, and the MSM was 0.14 and 0.30 mL/min/g, respectively. The estimated radiation dose required for the FPA technique with two volume scans and the MSM was 2.6 and 11.7-17.5 mSv, respectively. Therefore, the FPA technique can yield accurate perfusion measurements using as few as two volume scans, corresponding to approximately a factor of four reductions in radiation dose as compared with the currently available MSM. In conclusion, the results of the study indicate that the FPA technique can make accurate dynamic CT perfusion measurements over a range of clinically relevant perfusion rates, while substantially reducing radiation dose, as compared to currently available dynamic CT perfusion techniques.

  10. [Value of perfusion scintigraphy of the testis].

    Science.gov (United States)

    Kotzerke, J; Erpenbach, K; Hengst, W

    1987-10-01

    Perfusion scintigraphy of the testicles has still its place, in addition to scrotal ultrasound imaging, in the investigation of the "acute scrotum". It reveals scintigraphic patterns typical for twisted testicle and acute or subacute epididymitis. Especially in the Bundeswehr, with its large number of young men, this method enhances the diagnostic spectrum and helps in making surgical decisions. However, in the examination of scrotal masses, ultrasound imaging or surgery is to be preferred.

  11. The evolution of perfusion education in America.

    Science.gov (United States)

    Toomasian, John M; Searles, Bruce; Kurusz, Mark

    2003-07-01

    Clinical cardiopulmonary perfusion has evolved significantly during its 50 years. The science, technology and educational processes related to cardiopulmonary bypass have undergone continual change and metamorphosis. Perfusionists were initially trained on the job or in the laboratory, but with the advent of myocardial revascularization and the explosion in cardiac surgery, the need for formal educational training programs became apparent. The American Society of Extracorporeal Technology began the arduous processes of credentialing and developing certification guidelines that have continued under the American Board of Cardiovascular Perfusion. Licensure has also been adopted in many states during the past 10 years where nearly 50% of all perfusionists are covered by some legislative act. One additonal challenge has been developing minimal standards in which perfusionists practice. The initial standards included the use of a checklist and have evolved to monitoring and recording the significant events and parameters of each clinical procedure. The education of perfusionists will continue to be a challenge related primarily to reduced fiscal resources, the applicant pool and the ever-changing demands for extracorporeal circulation services. According to demographic and census information, it is expected the overall number of cardiovascular interventions will increase dramatically towards the latter end of the current decade in the US. The question arises as to what role perfusionists will play, as treatment strategies continue to change. If the number of education programs and new graduates continue to decline, the total number of perfusionists will decline, especially as many senior perfusionists leave the field or retire. It may be difficult to predict the total number of cardiovascular interventions that will be required in the next several years. However, if the total number of cardiovascular interventions that require perfusion services increase as a function

  12. Myocardial perfusion studies in coronary diseases

    International Nuclear Information System (INIS)

    Mut, Fernando

    1994-01-01

    For detecting in precocious form a coronary disease is necessary to apply a diagnostic techniques. The main considerations to be indicated in the present work are: physiological considerations, myocardial perfusion studies with radiotracers such as Talio 201, 99mTc, MIBI, 99mTc-Teboroxima, 99mTc-Fosfinas, instrumentation for obtain good images,proceedings protocols, studies interpretation, standards, SPECT, anomalies standards, coronary diseases

  13. Regional cerebral perfusion in cardiovascular reflex syncope

    International Nuclear Information System (INIS)

    Toeyry, J.P.; Kuikka, J.T.; Laensimies, E.A.

    1997-01-01

    Little is known about the regional cerebral perfusion in subjects with presyncope or syncope, and the impact that autonomic nervous dysfunction has on it. Seven subjects with cardiovascular vasodepressor reflex syncope were studied. A baseline test was performed with the patients standing in the 70 upright position, while the passive head-up tilt table test with and without isoprenaline infusion was employed for provocation. Regional cerebral perfusion was assessed by means of single-photon emission tomography with technetium-99m labelled V-oxo-1,2-N,N 1 -ethylenedylbis-l-cysteine diethylester (baseline, and during blood pressure decline in the provocation test) and the autonomic nervous function by means of spectral analysis of heart rate variability (baseline, and before blood pressure decline in the provocation test). Every subject showed an abrupt decline in blood pressure in the provocation test (five with presyncope and two with syncope). The systolic and diastolic blood pressures decreased significantly (P<0.001) between the baseline and the provocation study time points (radiopharmaceutical injection and lowest systolic blood pressure). Mean cerebral perfusion as average count densities decreased upon provocation as compared with baseline (190±63 vs 307±90 counts/voxel, respectively, P=0.013). Hypoperfusion was most pronounced in the frontal lobe. These results suggest that cerebral perfusion decreases markedly during presyncope or syncope with systemic blood pressure decline in subjects with cardiovascular vasodepressor syncope. Furthermore, the autonomic nervous function remains unchanged before the systemic blood pressure decline. (orig.). With 3 figs., 2 tabs

  14. Towards robust deconvolution of low-dose perfusion CT: Sparse perfusion deconvolution using online dictionary learning

    Science.gov (United States)

    Fang, Ruogu; Chen, Tsuhan; Sanelli, Pina C.

    2014-01-01

    Computed tomography perfusion (CTP) is an important functional imaging modality in the evaluation of cerebrovascular diseases, particularly in acute stroke and vasospasm. However, the post-processed parametric maps of blood flow tend to be noisy, especially in low-dose CTP, due to the noisy contrast enhancement profile and the oscillatory nature of the results generated by the current computational methods. In this paper, we propose a robust sparse perfusion deconvolution method (SPD) to estimate cerebral blood flow in CTP performed at low radiation dose. We first build a dictionary from high-dose perfusion maps using online dictionary learning and then perform deconvolution-based hemodynamic parameters estimation on the low-dose CTP data. Our method is validated on clinical data of patients with normal and pathological CBF maps. The results show that we achieve superior performance than existing methods, and potentially improve the differentiation between normal and ischemic tissue in the brain. PMID:23542422

  15. Transport of benzo[alpha]pyrene in the dually perfused human placenta perfusion model: effect of albumin in the perfusion medium

    DEFF Research Database (Denmark)

    Mathiesen, Line; Rytting, Erik; Mose, Tina

    2009-01-01

    Transport of benzo[alpha]pyrene (BaP) across the placenta was examined because it is a ubiquitous and highly carcinogenic substance found in tobacco smoke, polluted air and certain foods. Foetal exposure to this substance is highly relevant but is difficult to estimate. The human placenta is unique...... compared to other species; since it is available without major ethical obstacles, we have used the human placenta perfusion model to study transport from mother to foetus. Placentas were donated after births at Rigshospitalet in Copenhagen from pregnant mothers who signed an informed consent. Ba......P is lipophilic and studies using cell culture medium in 6-hr placenta perfusions showed minimal transport through the placenta. To increase the solubility of BaP in perfusion medium and to increase physiological relevance, perfusions were also performed with albumin added to the perfusion medium [2 and 30 mg...

  16. Myocardial perfusion in type 2 diabetes with left ventricular hypertrophy

    DEFF Research Database (Denmark)

    Hesse, Birger; Meyer, Christian; Nielsen, Flemming S

    2004-01-01

    The purpose of this study was to assess whether acute angiotensin-converting enzyme (ACE) inhibition would improve myocardial perfusion and perfusion reserve in a subpopulation of normotensive patients with diabetes and left ventricular hypertrophy (LVH), both independent risk factors of coronary...... disease. Using positron emission tomography (PET), we investigated the response of regional myocardial perfusion to acute ACE inhibition with i.v. infusion of perindoprilat (vs saline infusion as control, minimum interval 3 days) in 12 diabetic patients with LVH. Myocardial perfusion was quantified...... with controls, maximal perfusion was reduced in patients (1.8+/-0.6 vs 2.5+/-1.0 ml min(-1) g(-1); P2.7+/-1.0 vs 3.6+/-1.3; P=0.059). During perindoprilat infusion, myocardial perfusion reserve in patients increased to 3.9+/-0.9 ( P

  17. Magnetic Resonance Imaging of Ventilation and Perfusion in the Lung

    Science.gov (United States)

    Prisk, Gordon Kim (Inventor); Hopkins, Susan Roberta (Inventor); Buxton, Richard Bruce (Inventor); Pereira De Sa, Rui Carlos (Inventor); Theilmann, Rebecca Jean (Inventor); Cronin, Matthew Vincent (Inventor)

    2017-01-01

    Methods, devices, and systems are disclosed for implementing a fully quantitative non-injectable contrast proton MRI technique to measure spatial ventilation-perfusion (VA/Q) matching and spatial distribution of ventilation and perfusion. In one aspect, a method using MRI to characterize ventilation and perfusion in a lung includes acquiring an MR image of the lung having MR data in a voxel and obtaining a breathing frequency parameter, determining a water density value, a specific ventilation value, and a perfusion value in at least one voxel of the MR image based on the MR data and using the water density value to determine an air content value, and determining a ventilation-perfusion ratio value that is the product of the specific ventilation value, the air content value, the inverse of the perfusion value, and the breathing frequency.

  18. Reversible ventilation and perfusion abnormalities in unilateral obstructed lung

    International Nuclear Information System (INIS)

    Ward, H.E.; Jones, R.L.; King, E.G.; Sproule, B.J.; Fortune, R.L.

    1982-01-01

    An intraluminal carcinoid tumor obstructing the left mainstem bronchus produced hypoxemia through alteration in ventilation/perfusion matching. Studies of regional lung function using 133-xenon (/sup 133/Xe) and a multiprobe computerized instrumentation system documented a reduction of perfusion to 22 percent and ventilation to 6 percent of the total. There was negligible washout of intravenously injected /sup 133/Xe from the left lung consistent with air trapping. Four days after left mainstem bronchial sleeve resection, perfusion, ventilation and washout of injected xenon had significantly improved and by four months postresection, all measurements were virtually normal, although complete restoration of perfusion in relation to ventilation was delayed. Regional lung function studied with a multiprobe system in this patient provided a clinical model for the study of ventilation and perfusion inter-relationships in large airway obstruction and demonstrated that a prolonged time may be required for return of perfusion to normal

  19. Brain perfusion: computed tomography and magnetic resonance techniques.

    Science.gov (United States)

    Copen, William A; Lev, Michael H; Rapalino, Otto

    2016-01-01

    Cerebral perfusion imaging provides assessment of regional microvascular hemodynamics in the living brain, enabling in vivo measurement of a variety of different hemodynamic parameters. Perfusion imaging techniques that are used in the clinical setting usually rely upon X-ray computed tomography (CT) or magnetic resonance imaging (MRI). This chapter reviews CT- and MRI-based perfusion imaging techniques, with attention to image acquisition, clinically relevant aspects of image postprocessing, and fundamental differences between CT- and MRI-based techniques. Correlations with cerebrovascular physiology and potential clinical applications of perfusion imaging are reviewed, focusing upon the two major classes of neurologic disease in which perfusion imaging is most often performed: primary perfusion disorders (including ischemic stroke, transient ischemic attack, and reperfusion syndrome), and brain tumors. © 2016 Elsevier B.V. All rights reserved.

  20. Quantitative analysis of SPECT imaging parameters in patients with resting perfusion defects on myocardial perfusion scintigraphy

    International Nuclear Information System (INIS)

    Pruthi, Ankur; Asopa, Ramesh; Rajan, M.G.R.; Basu, Sandip

    2010-01-01

    Functional status/contractile behaviour of hibernating myocardium was analyzed objectively by analyzing the available quantitative parameters obtained on gated SPECT myocardial perfusion imaging (MPI) using Emory cardiac toolbox (ECTB) software. Materials and Methods: In this retrospective study, 70 patients with perfusion defects on 99 Tc-Sestamibi MPI (12 females, 58 males) who also underwent 18 F-FDG Cardiac PET study for assessment of hibernating myocardium were included for analysis. Patients were divided in three categories based on summed rest score (SRS) obtained from ECTB software, depicting the extent of perfusion defects. In a study population matched for extent of perfusion defects, quantitative parameters obtained from ECTB software such as left ventricular ejection fraction (LVEF), left ventricular end diastolic volume (EDV), left ventricular end systolic volume (ESV) and left ventricular stroke volume (SV) were compared between patients showing evidence of hibernating myocardium and patients showing no evidence of hibernating myocardium. Student 't' test was applied on the given observations and a P-value <0.05 was considered as a significant difference between the means in two categories. Results: There was no significant difference in LVEF, EDV, ESV and SV measurements between those who demonstrate hibernating myocardium and those who show no evidence of hibernating myocardium across all the categories of patients. Few trends were evident in the present study in LVEF, EDV and ESV measurements i.e., fall in mean LVEF with increasing SRS and rise in mean EDV and ESV with increasing SRS. Conclusions: The findings were consistent with the nature of hibernating myocardium i.e., non-contractile and dysfunctional. The fall in the LVEF was suggestive of deteriorating myocardial function with increasing extent of perfusion defects. The increasing left ventricular EDV and ESV with increasing extent of perfusion defects was suggestive of rising incidence of

  1. Whole-brain dynamic CT angiography and perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Orrison, W.W. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Department of Medical Education, University of Nevada School of Medicine, Reno, NV (United States); Snyder, K.V.; Hopkins, L.N. [Department of Neurosurgery, Millard Fillmore Gates Circle Hospital, Buffalo, NY (United States); Roach, C.J. [School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Ringdahl, E.N. [Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV (United States); Nazir, R. [Shifa International Hospital, Islamabad (Pakistan); Hanson, E.H., E-mail: eric.hanson@amigenics.co [College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States)

    2011-06-15

    The availability of whole brain computed tomography (CT) perfusion has expanded the opportunities for analysing the haemodynamic parameters associated with varied neurological conditions. Examples demonstrating the clinical utility of whole-brain CT perfusion imaging in selected acute and chronic ischaemic arterial neurovascular conditions are presented. Whole-brain CT perfusion enables the detection and focused haemodynamic analyses of acute and chronic arterial conditions in the central nervous system without the limitation of partial anatomical coverage of the brain.

  2. Perfusion lung scanning: differentiation of primary from thromboembolic pulmonary hypertension

    International Nuclear Information System (INIS)

    Lisbona, R.; Kreisman, H.; Novales-Diaz, J.; Derbekyan, V.

    1985-01-01

    Of eight patients with pulmonary arterial hypertension, final diagnosis established by autopsy or angiography, four had primary hypertension and four hypertension from thromboembolism. The perfusion lung scan was distinctly different in the two groups. The lung scan in primary pulmonary hypertension was associated with nonsegmental, patchy defects of perfusion, while in thromboembolic hypertensives it was characterized by segmental and/or lobar defects of perfusion with or without subsegmental defects. The perfusion lung scan is a valuable, noninvasive study in the evaluation of the patient with pulmonary hypertension of undetermined cause and in the exclusion of occult large-vessel pulmonary thromboembolism

  3. Effect of Defocused CO2 Laser on Equine Tissue Perfusion

    Directory of Open Access Journals (Sweden)

    Bergh A

    2006-03-01

    Full Text Available Treatment with defocused CO2 laser can have a therapeutic effect on equine injuries, but the mechanisms involved are unclear. A recent study has shown that laser causes an increase in equine superficial tissue temperature, which may result in an increase in blood perfusion and a stimulating effect on tissue regeneration. However, no studies have described the effects on equine tissue perfusion. The aim of the present study was to investigate the effect of defocused CO2 laser on blood perfusion and to correlate it with temperature in skin and underlying muscle in anaesthetized horses. Differences between clipped and unclipped haircoat were also assessed. Eight horses and two controls received CO2 laser treatment (91 J/cm2 in a randomised order, on a clipped and unclipped area of the hamstring muscles, respectively. The significant increase in clipped skin perfusion and temperature was on average 146.3 ± 33.4 perfusion units (334% and 5.5 ± 1.5°C, respectively. The significant increase in perfusion and temperature in unclipped skin were 80.6 ± 20.4 perfusion units (264% and 4.8 ± 1.4°C. No significant changes were seen in muscle perfusion or temperature. In conclusion, treatment with defocused CO2 laser causes a significant increase in skin perfusion, which is correlated to an increase in skin temperature.

  4. Perfusion CT imaging of the liver: review of clinical applications

    Science.gov (United States)

    Oğul, Hayri; Kantarcı, Mecit; Genç, Berhan; Pirimoğlu, Berhan; Çullu, Neşat; Kızrak, Yeşim; Yılmaz, Ömer; Karabulut, Nevzat

    2014-01-01

    Perfusion computed tomography (CT) has a great potential for determining hepatic and portal blood flow; it offers the advantages of quantitative determination of lesion hemodynamics, distinguishing malignant and benign processes, as well as providing morphological data. Many studies have reported the use of this method in the assessment of hepatic tumors, hepatic fibrosis associated with chronic liver disease, treatment response following radiotherapy and chemotherapy, and hepatic perfusion changes after radiological or surgical interventions. The main goal of liver perfusion imaging is to improve the accuracy in the characterization of liver disorders. In this study, we reviewed the clinical application of perfusion CT in various hepatic diseases. PMID:24834487

  5. Prior CT May Improve Diagnostic Confidence in Myocardial Perfusion Imaging.

    Science.gov (United States)

    Mehta, Pareen; Wassef, Heidi; Colletti, Patrick M

    2015-10-01

    Many patients with matching myocardial perfusion imaging defects may have prior CT examinations that include the myocardial region of interest, such as a CT chest or CT abdomen. We correlate these perfusion defects with available prior CT examinations to determine if this will improve diagnostic confidence. Myocardial perfusion scans were reviewed to identify cases with myocardial perfusion defects and prior CT imaging that included the myocardium. The CT was reviewed for evidence of myocardial injury that correlated with the perfusion defect. A retrospective review of 732 myocardial perfusion scans was performed, of which 69 cases with perfusion defects were identified that also had prior CT imaging available for review. Of this subset of patients, 19 patients had findings on the CT scan compatible with ischemia or infarction in the expected region of the perfusion defect, which allowed for a more confident diagnosis. Reviewing a prior CT scan, if available, during the interpretation of a myocardial perfusion scan, can help improve diagnostic confidence in over 25% of cases. This can lead to decreased indeterminate results and can be used to potentially avoid unhelpful further testing.

  6. Perfusion index as a possible predictor for postanesthetic shivering.

    Science.gov (United States)

    Kuroki, Chiharu; Godai, Kohei; Hasegawa-Moriyama, Maiko; Kuniyoshi, Tamotsu; Matsunaga, Akira; Kanmura, Yuichi; Kuwaki, Tomoyuki

    2014-02-01

    Postanesthetic shivering can be triggered by surgical stress and several aspects of anesthetic management and is frequently preceded by a decrease in peripheral blood flow due to thermoregulatory vasoconstriction. As perfusion index correlates with peripheral blood flow, we examined whether perioperative perfusion index, measured using pulse oximetry, might be correlated with postanesthetic shivering. Twenty-eight patients presenting for elective abdominal surgery were enrolled. Core (esophagus) and peripheral (finger) temperatures and perfusion index were recorded in the perioperative periods. Correlations between perfusion index and peripheral temperature and core-to-peripheral temperature gradient were then explored. Plasma levels of epinephrine and norepinephrine were also measured. The extent of shivering was graded after emergence from anesthesia. Perfusion index declined before emergence from anesthesia in patients who then developed postanesthetic shivering. This coincided with the time at which the difference between core and peripheral temperature became dissociated and peripheral temperature declined. Perioperative perfusion index was correlated with peripheral temperature and peripheral-core temperature gradient. Perfusion index at closure of the peritoneum predicted postanesthetic shivering and was significantly correlated with the extent of shivering. Plasma levels of both epinephrine and norepinephrine were significantly elevated after shivering events. Perfusion index was significantly lower in patients with postanesthetic shivering before emergence from anesthesia, indicating that measurement of perfusion index during and before the end of anesthesia might be a useful means of predicting postanesthetic shivering.

  7. Indirekt-lymphographische Befunde bei Lymphödemen und Lipödemen der unteren Extremitäten unter besonderer Berücksichtigung ihrer Mischformen

    OpenAIRE

    Knorz, Siegfried

    2000-01-01

    In der Arbeit werden die Untersuchungsmethoden der Lymphograpie, Xeroradiographie und der Isotopenlymphographie bei der Diagnostik von Lymphödemen, insbesondere von Mischformen, verglichen. Als Alternative zur Xeroradiographie für die Bildgebung bei der indirekten Lymphographie werden die Verfahren der digitalen Speicherfolien-Radiographie und der digitalen Bildverstärker-Radiographie vorgestellt.

  8. Padrões Contábeis internacionais do IASB: Um estudo comparativo com as normas contábeis brasileiras e sua aplicação

    Directory of Open Access Journals (Sweden)

    L. Nelson Carvalho

    2009-10-01

    Full Text Available Atribui-se a Jonh Kennteh Galbraith a afirmativa de que os economistas deveriam se preocupar em medir "Felicidade Nacional Bruta" do que "Produto Nacional Bruto" e que "Felicidade", objetivamente considerada , é o pai da família ou jovem em idade de trabalho a encontratem emprego e oportunidades. Isso se dá, em grande parte, por um setor empresarial empreendedor, e este mostra sua vitalidade por meio de mecanismos de comunicação que espelhem suas virtudes. O melhor, o mais clássico e universal - conquanto não é o único- mecanismo de comunicação de desempenho empresarial com credores , investidores, governo, fornecedores é o conjunto das demonstrações contábeis.

  9. Phthalate monoesters in perfusate from a dual placenta perfusion system, the placenta tissue and umbilical cord blood

    DEFF Research Database (Denmark)

    Mose, Tina; Mortensen, Gerda K; Hedegaard, Morten

    2006-01-01

    BP), and mono (2-ethyl-hexyl) phthalate (mEHP) were detected in both maternal and fetal perfusate, demonstrating a release of compounds from tissue or blood to perfusates. The distribution of compounds between perfusate, umbilical cord plasma, and tissue was in accordance with the physical-chemical properties...... of the compounds. Results from the present study of compounds residing in the tissue are essential before studying human transplacental transfer, storage, and metabolism of selected phthalate monoesters....

  10. 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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-11-01

    wichtige Ursache von Schlaganfaellen bei juengeren Erwachsenen. Wir untersuchten die diagnostischen Moeglichkeiten der Magnetresonanzangiographie (MRA) in Kombination mit der Magnetresonanztomographie (MRT) bei vertebrobasilaeren Dissektionen anhand einer retrospektiven Analyse von 24 Patienten mit einer Vertebralisdissektion und einem Patienten mit einer Basilarisdissektion. Bei 24 von 25 Patienten (95,5%) wurden mit der Magnetresonanzangiographie abnorme Flussverhaeltnisse im disseziierten Gefaess erkannt. Die Sensitivitaet der konventionellen Angiographie war 100% und die des Ultraschalls 77%. In 7 Faellen (30,4%) ergab die Magnetresonanz spezifische Hinweise auf eine Dissektion (Doppellumen n=1, murales Haematom n=4, Pseudoaneurysma n=2). Demgegenueber standen 36,4% spezifische Befunde in der Angiographie. Dabei waren die spezifischen Resultate von MRT/MRA und Angiographie z.T. komplementaer, beide Methoden zusammen erzielten 43,5% Spezifitaet. Die kombinierte MRT und MRA kann bei etwa 1/3 der Patienten bereits die Diagnose einer Vertebralisdissektion stellen. Bei den anderen Patienten kann die Indikation zur konventionellen Angiographie verbessert werden. Dies gilt besonders fuer jene Patienten mit unspezifischen Prodromalsymptomen. Eine negative Magnetresonanzuntersuchung erzetzt bei Patienten mit hinweisenden Symptomen die konventionelle Angiographie allerdings nicht. Die Angiographie wird aufgrund der hoeheren Ortsaufloesung und der sicheren Beurteilbarkeit auch des proximalen V Abschnittes 1 vorerst diagnostischer Standard bleiben. (orig.)

  12. Perfusion Intensity Correlates with Expression Levels of Psoriasis-Related Genes and Proteins

    NARCIS (Netherlands)

    Hendriks, Anke G M; Steenbergen, Wiendelt; Zeeuwen, Patrick L J M; Schalkwijk, Joost; Hondebrink, Erwin; Klitsie, Michiel A J; Schreurs, Ruud; Van De Kerkhof, Peter C M; Seyger, Marieke M B

    2015-01-01

    Background: Previous research revealed heterogeneity in the perfusion intensity within clinically homogenous-Appearing plaques, without differences in erythema. In addition, an increased perfusion was found within the perilesional skin. This raises the question whether the heterogeneity in perfusion

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-01-01

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

  14. 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

  15. Aspects of radiation protection during chest X-radiography; Strahlenhygienische Aspekte bei der Roentgenuntersuchung des Thorax

    Energy Technology Data Exchange (ETDEWEB)

    Seidenbusch, M.C.; Schneider, K. [Dr. von Haunersches Kinderspital, Klinikum der Universitaet Muenchen, Institut fuer Klinische Radiologie - Kinderradiologie, Muenchen (Germany)

    2015-07-15

    Radiation safety in conventional X-ray diagnostics is based on the concepts of justification, optimization of an X-ray examination and limitation of the radiation exposure achieved during the examination. Optimization of an X-ray examination has to be considered as a multimodal process in which all technical components of the X-ray equipment have to be adapted to each other and also have to be adapted to the anthropometric characteristics of patients and the clinical indications. In this article the technical components of a conventional pediatric chest X-radiograph are presented, and recommendations for optimizing chest X-rays in children are provided. The following measures are of prime importance: correct x-ray beam limitation, using the posteroanterior projection when possible and not using anti-scatter grids in children under approximately 8 years old. In pediatric radiology chest x-rays that are taken not at the peak of inspiration can also be of some diagnostic significance. Optimization of an X-ray examination inevitably results in the limitation of radiation exposure. (orig.) [German] Die Strahlenhygiene in der konventionellen radiologischen Diagnostik basiert auf der Trias Rechtfertigung, Optimierung bzw. Limitierung der Roentgenuntersuchung bzw. Strahlenexposition. Die Optimierung einer Roentgenuntersuchung ist als multimodaler Prozess aufzufassen, in welchem saemtliche technische Komponenten der Roentgeneinrichtung sowohl miteinander als auch mit den anthropometrischen Eigenschaften des Patienten und der klinischen Fragestellung abzustimmen sind. Im vorliegenden Beitrag werden die technischen Komponenten bei der konventionellen Roentgenuntersuchung des paediatrischen Thorax in ihrer Beziehung zueinander dargestellt und Empfehlungen fuer eine Optimierung der konventionellen Thoraxaufnahme bei Kindern ausgesprochen. Die wichtigsten Massnahmen bestehen in einer korrekten Einblendung, in der Anfertigung der Aufnahmen im posteroanterioren Strahlengang und im

  16. Metabolomic perfusate analysis during kidney machine perfusion: the pig provides an appropriate model for human studies.

    Directory of Open Access Journals (Sweden)

    Jay Nath

    Full Text Available Hypothermic machine perfusion offers great promise in kidney transplantation and experimental studies are needed to establish the optimal conditions for this to occur. Pig kidneys are considered to be a good model for this purpose and share many properties with human organs. However it is not established whether the metabolism of pig kidneys in such hypothermic hypoxic conditions is comparable to human organs.Standard criteria human (n = 12 and porcine (n = 10 kidneys underwent HMP using the LifePort Kidney Transporter 1.0 (Organ Recovery Systems using KPS-1 solution. Perfusate was sampled at 45 minutes and 4 hours of perfusion and metabolomic analysis performed using 1-D 1H-NMR spectroscopy.There was no inter-species difference in the number of metabolites identified. Of the 30 metabolites analysed, 16 (53.3% were present in comparable concentrations in the pig and human kidney perfusates. The rate of change of concentration for 3-Hydroxybutyrate was greater for human kidneys (p<0.001. For the other 29 metabolites (96.7%, there was no difference in the rate of change of concentration between pig and human samples.Whilst there are some differences between pig and human kidneys during HMP they appear to be metabolically similar and the pig seems to be a valid model for human studies.

  17. Xeno- and auto-perfusion of rabbit kidney. Machine perfusion with blood at 37 degrees C

    DEFF Research Database (Denmark)

    Jørgensen, K A; Kemp, E; Barfort, P

    1985-01-01

    Five rabbit kidneys were perfused with human blood and another five with their own blood in a re-circulating oxygenated system at 37 degrees C. The flow decreased to 2 ml/min. within 30 min. in all xenoperfusions, while none of the autoperfused had decreased to this level by 60 min. Endothelial...

  18. Retrospektive Analyse von Zufallsbefunden, die bei Patienten mit kutanem malignen Malignom durch (18) F-Fluordeoxyglucose-PET/CT erhoben wurden.

    Science.gov (United States)

    Conrad, Franziska; Winkens, Thomas; Kaatz, Martin; Goetze, Steven; Freesmeyer, Martin

    2016-08-01

    Bei der (18) F-Fluordeoxyglucose-Positronenemissionstomographie/Computertomographie (FDG-PET/CT) ergeben sich häufig Zufallsbefunde. In der vorliegenden Studie konzentrierten wir uns auf mittels FDG-PET/CT erhaltene Zufallsbefunde bei Patienten mit kutanem Melanom und überprüften deren Relevanz hinsichtlich weiterer diagnostischer Maßnahmen und Interventionen. Die Krankenakten von 181 konsekutiven Melanom-Patienten wurden retrospektiv ausgewertet, um das Management von Zufallsbefunden zu dokumentieren. Der Schwerpunkt lag dabei auf den histologischen Befunden. Bei 33 von 181 (18 %) Patienten lagen 39 relevante Zufallsbefunde vor, und zwar im Kolorektalbereich (n = 15 Patienten), in der Schilddrüse (n = 8), der Prostata (n = 2), dem Bewegungsapparat (n = 2), in Lymphknoten (n = 2), der Parotis (n = 1), den Mandeln (n = 1), den Nieren (n = 1) und der Gallenblase (n = 1). Bei 25 Patienten schlossen sich weitere diagnostische Verfahren an, wobei in 21 Fällen ein klinisches Korrelat nachgewiesen wurde. Bei 16 von 21 Patienten ergab sich eine Neoplasie, darunter fünf maligne Läsionen (vier Kolonkarzinome und ein Prostatakarzinom). Die Malignome wurden frühzeitig diagnostiziert und in der Mehrzahl der Fälle erfolgreich entfernt. Der Einsatz der FDG-PET/CT als Routine-Diagnostik wird in den Leitlinien empfohlen und ist indiziert bei malignem Melanom ab Stadium IIC. In dieser Studie wurden auf effektive Weise ansonsten nicht erkannte Krebserkrankungen, insbesondere Kolonkarzinome, detektiert. In den meisten Fällen war eine frühe Intervention möglich. Zufallsbefunde durch FDG-PET/CT sollten, unter Berücksichtigung des Zustands und der Wünsche des Patienten, mit den geeigneten diagnostischen Maßnahmen abgeklärt werden. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  19. Der Einfluss von Alitretinoin auf die Lebensqualität bei Patienten mit schwerem chronischen Handekzem: FUGETTA - Beobachtungsstudie unter Praxisbedingungen.

    Science.gov (United States)

    Augustin, Matthias; Thaçi, Diamant; Kamps, Anja

    2016-12-01

    Alitretinoin ist die einzige zugelassene Behandlung für schweres chronisches Handekzem (CHE), das refraktär gegenüber potenten topischen Corticosteroiden ist. Bei dieser Studie (FUGETTA) wurde die Wirksamkeit von leitliniengerecht angewendetem oralem Alitretinoin sowie dessen Einfluss auf die Lebensqualität (LQ) bei Patienten mit schwerem refraktärem CHE beurteilt. Multizentrische, offene, nichtinterventionelle Beobachtungsstudie, durchgeführt in Deutschland. Die Patienten wurden nach Ermessen ihres behandelnden Arztes mit Alitretinoin 10 mg oder 30 mg einmal täglich über maximal 24 Wochen behandelt. Die Wirksamkeit wurde anhand des Physician Global Assessment (PGA) und des Dermatology Life Quality Index (DLQI) bewertet. Zudem wurden unerwünschte Ereignisse (UE) erfasst. Die Studienpopulation bestand aus 658 Patienten (30 mg: n = 581; 10 mg: n = 77). Bei Beobachtungsbeginn litten die meisten Patienten (83 %) gemäß PGA an einem schweren CHE. Bei Beobachtungsende war das Handekzem bei 48 % der Patienten gemäß PGA vollständig oder fast vollständig abgeheilt (30 mg: 49 %; 10 mg: 43 %). Die mittlere Verbesserung des DLQI-Scores in Woche 24 betrug 58 % (30 mg: mittlere [SD] Veränderung gegenüber dem Ausgangswert -10,4 [8,04]) und 70 % (10 mg: mittlere [SD] Veränderung gegenüber dem Ausgangswert -10,8 [7,29]). Die Gesamtinzidenz von NW war niedrig und in den beiden Gruppen ähnlich. Alitretinoin führte zu einer schnellen, deutlichen Verbesserung der LQ bei Patienten mit schwerem CHE. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  20. Pseudoketogenesis in the perfused rat heart

    Energy Technology Data Exchange (ETDEWEB)

    Fink, G.; Desrochers, S.; Des Rosiers, C.; Garneau, M.; David, F.; Daloze, T.; Landau, B.R.; Brunengraber, H.

    1988-12-05

    Ketogenesis is usually measured in vivo by dilution of tracers of (3R)-hydroxybutyrate or acetoacetate. We show that, in perfused working rat hearts, the specific activities of (3R)-hydroxybutyrate and acetoacetate are diluted by isotopic exchanges in the absence of net ketogenesis. We call this process pseudoketogenesis. When hearts are perfused with buffer containing 2.3 mM of (4-3H)- plus (3-14C)acetoacetate, the specific activities of (4-3H) and (3-14C)acetoacetate decrease while C-1 of acetoacetate becomes progressively labeled with 14C. This is explained by the reversibility of reactions catalyzed by mitochondrial 3-oxoacid-CoA transferase and acetoacetyl-CoA thiolase. After activation of labeled acetoacetate, the specific activity of acetoacetyl-CoA is diluted by unlabeled acetoacetyl-CoA derived from endogenous fatty acids or glucose. Acetoacetyl-CoA thiolase partially exchanges 14C between C-1 and C-3 of acetoacetyl-CoA. Finally, 3-oxoacid-CoA transferase liberates weakly labeled acetoacetate which dilutes the specific activity of extracellular acetoacetate. An isotopic exchange in the reverse direction is observed when hearts are perfused with unlabeled acetoacetate plus (1-14C)-, (13-14C)-, or (15-14C)palmitate; here also, acetoacetate becomes labeled on C-1 and C-3. Computations of specific activities of (3R)-hydroxybutyrate, acetoacetate, and acetyl-CoA yield minimal rates of pseudoketogenesis ranging from 19 to 32% of the net uptake of (3R)-hydroxybutyrate plus acetoacetate by the heart.

  1. Myocardial perfusion tomography with 7-pinhole collimator

    Energy Technology Data Exchange (ETDEWEB)

    Yonekura, Y.; Mukai, T.; Yamamoto, K. (Kyoto Univ. (Japan). Faculty of Medicine)

    1980-12-01

    The clinical efficacy of tomographic presentation of myocardial perfusion imaging with 7-pinhole collimator was evaluated. 35 cases including 5 normals, 4 patients with diffuse left ventricular hypertrophy, 21 with coronary artery disease (CAD) and 5 with hypertrophic cardiomyopathy (HCM) documented by coronary angiography and left ventriculography were selected for this study. Following the conventional /sup 201/Tl myocardial perfusion imaging (MPI), myocardial perfusion tomography (MPT) with 7-pinhole collimator was performed in both LAO and RAO projection. In addition, to examine wall motion abnormalities tomographically, /sup 201/Tl MPI as well as sup(99m)Tc-RBC blood pool imaging were gated to reconstruct multigated MPT (MGMPT) and multigated cardiac pool tomography (MGCPT). The detectability of the defect of the 7-pinhole tomography was compared with that of the conventional image using a cardiac phantom. The same degree of detectability was shown with both these two images. The MPT in LAO projection revealed superior sensitivity to the conventional MPI in the case of inferior wall infarction, and the MPT in RAO projection revealed superior sensitivity in the case of anterior wall infarction. A combination of the MGMPT and MGCPT succeeded in visualizing a subendocardial infarction as a focal gap between these two images. In the case of the small infarction undetectable in the conventional MPI, it can be seen as subtle wall motion abnormalities in the tomographic presentation in movie format. An asymmetrical hypertrophy in HCM can readily be localized in tomographic visualization. Tomographic reconstruction with 7-pinhole collimator from the optimal tomographic plane should be attempted, when the conventional display is equivocal.

  2. Radiological interventions in inflammatory bowel disease; Interventionelle Verfahren bei entzuendlichen Darmerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Krolak, C.; Rock, C.; Reiser, M. [Institut fuer Klinische Radiologie, Klinikum der Universitaet Muenchen (Germany)

    2003-01-01

    Abscesses, fistulas,hemorrhages and stenoses are common complications of inflammatory bowel diseases.This study provides an overview on various methods of radiological intervention and the clinical usefulness of these methods is analyzed. The success rate of percutaneous abscess drainage (PAD), embolisation of hemorrhages and dilatation of bowel stenoses is reviewed and current literature is adressed.Success rate is defined in terms of cure rate and need for subsequent surgery. After PAD, surgery can be avoided during the observation period in about 50% of patients with abscesses due to Crohn's disease and diverticulitis.Preoperative PAD reduces the degree of invasiveness and thus the risk of surgery.Abscess recurrence is found with the same frecuency following surgery or PAD.Bowel dilatation can be performed both with radiological and with endoscopic guidance.Embolisation of GI-hemorrhage is technically feasible, but the indication should be limited to strictly selected cases. In treating abscesses and fistulas associated with Crohn's disease and diverticulitis, PAD is a valuable treatment option.Embolisation or dilatation are restricted to rare cares. (orig.) [German] Fragestellung Abszesse, Fisteln, Blutungen und Darmstenosen sind typische Komplikationen entzuendlicher Darmerkrankungen. Es werden verschiedene radiologisch-interventionelle Verfahren vorgestellt und ihre Wertigkeit fuer die Behandlung geprueft.Methodik Unter Beruecksichtigung der neueren Literatur werden der Erfolg der perkutanen Abszessdrainage (PAD) hinsichtlich der Ausheilung und Notwendigkeit einer folgenden OP, die perkutane Embolisation und die Dilatation von Darmstenosen bewertet.Ergebnisse Die PAD vermeidet bei 50% der Patienten mit Morbus Crohn und bei 20% der Patienten mit Divertikulitis eine OP im kurzfristigen Verlauf.Die PAD verringert die Invasivitaet einer nachfolgenden OP.Rezidivabszesse treten nach PAD und OP gleich haeufig auf.Die Dilatation entzuendlicher Darmstenosen

  3. 10-Jahres-Katamnese bei Alkoholkranken unter besonderer Berücksichtigung der Frauen

    OpenAIRE

    Kraus, Elvira

    2009-01-01

    In der vorliegenden 10-Jahres-Katamnese wurden 215 alkoholkranke Patienten, die in den Jahren 1993 und 1994 die sechswöchige stationäre und die sich anschließende einjährige ambulante Entwöhnungstherapie in der Universitätsklinik für Psychiatrie und Psychotherapie Tübingen durchlaufen haben, nachuntersucht. Die damalige Datenbasis beruht auf dem BMBF-Projekt „Langzeitverlauf und Rückfallprophylaxe bei alkoholabhängigen Frauen und Männern“ (Mann et al. 1996a). Die statistischen Berechnungen wu...

  4. Quality management and ecoaudit in organic waste treatment; Qualitaetsmanagement und Oeko-Audit bei der Bioabfallbehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Hangen, H.O. [comp.

    1996-12-31

    This conference volume discusses quality management and environmental management in biologicalwaste treatment. Subjects: DIN EN ISO 9000; Goals of the Eco-audit in theory and practice; Legal aspects; Cost reduction; Certification; Quality assurance by legal regulations; Introduction of a quality management system. (SR) [Deutsch] Dieser Tagungsband behandelt das Qualitaetsmanagement und das Umweltmanagement bei der Bioabfallbehandlung. Themen sind unter anderem: DIN EN ISO 9000, Ziele des Oeko-Audits in Theorie und Praxis, juristische Aspekte, Kostenersparnis, Zertifizierung, Qualitaetssicherung auf dem Verordnungswege und Einfuehrung eines Qualitaetsmanagementsystems. (SR)

  5. Konzepte und Methoden zur Qualitätssicherung bei der Produktion von hypertextuellen Online-Lernumgebungen

    Directory of Open Access Journals (Sweden)

    Christian Swertz

    2002-04-01

    Full Text Available Die didaktische Ontologie der Webdidaktik ermöglicht die Qualitätssicherung von Prozessen und Ergebnissen bei der Produktion von Online- Lernumgebungen. Die Qualität wird durch die am pädagogischen Prozess beteiligten Menschen bestimmt. Der Qualitätssicherungsprozess kann durch Software unterstützt werden. Für diese Prozesse der Qualitätssicherung bringt der Autor Beispiele aus dem Lerndorf (www.lerndorf.de und der Lernumgebung des von der Deutschen Bundesstiftung Umwelt geförderten Forschungs- und Entwicklungsprojekt «Zentrum für Umweltwissen und Bildung» (ZUB.

  6. Radiological intervention in postoperative complications following liver transplantation; Interventionelle radiologische Verfahren bei postoperativen Komplikationen nach Lebertransplantation

    Energy Technology Data Exchange (ETDEWEB)

    Berger, H. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern, Univ. Muenchen (Germany); Staebler, A. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern, Univ. Muenchen (Germany); Kunzfeld, A. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern, Univ. Muenchen (Germany); Zuelke, C. [Chirurgische Klinik und Poliklinik, Klinikum Grosshadern, Univ. Muenchen (Germany); Anthuber, M. [Chirurgische Klinik und Poliklinik, Klinikum Grosshadern, Univ. Muenchen (Germany); Kraemling, H.J. [Chirurgische Klinik und Poliklinik, Klinikum Grosshadern, Univ. Muenchen (Germany)

    1997-03-01

    Purpose: Postoperative complications contribute significantly to the morbidity and mortality of liver transplant patients. The management of these complications requires a multidisciplinary approach in which interventional radiology plays an integral role. Indications, techniques, and results of radiological interventions in the management of the liver transplant patient are presented. Material and methods: During a 10-year period, 52 out of 420 liver transplant recipients underwent radiological interventions, including angioplasty (n=20), embolization (n=2), percutaneous drainage (n=11), and biliary interventions (n=19). Results: Nine out of ten arterial stenoses located at the anastomoses (n=8), within the liver (n=1) and in the coeliac trunk (n=1) were successfully treated by balloon dilatation. Angioplasty of supra- or infrahepatic anastomotic stenoses of the IVC (n=5) provided long-term success only in combination with stent implantation. Portal vein stenoses and chronic thrombosis were treated by balloon dilatation and stent insertion via transhepatic catheterization of the portal vein. Late strictures of bile-duct anastomoses can be managed by ante- or retrograde interventions. If biliary complications are related to inflammatory or septic problems, the prognosis of graft survival is poor. Conclusion: Interventional radiological procedures are very useful in the management of vascular and biliary complications after liver transplantation. These techniques provide a cure in many situations, and thus, surgical interventions may be avoided in selected cases. (orig.) [Deutsch] Die komplexe chirurgisch-technische Operation sowie immunologische und ischaemieverursachte Probleme tragen zur relativ hohen Komplikationsrate nach Lebertransplantation bei, die grundsaetzlich organ- bzw. lebensbedrohlich fuer den Patienten sind. Interventionelle radiologische Techniken sind aufgrund ihres minimal-invasiven Charakters in der klinischen Versorgung dieser Komplikationen

  7. EXCESS CASH HOLDINGS DAN KEPEMILIKAN INSTITUSIONAL PADA PERUSAHAAN MANUFAKTUR YANG TERDAFTAR DI BEI

    Directory of Open Access Journals (Sweden)

    Yessica Tria Christina

    2014-02-01

    Full Text Available This research provides an empirical evidence about the effect of institutional ownerships as a proxy of information transparancy on excess cash holdings. Manufacture companies listed on BEI from years 2002 to 2011 are employed. The results show that the higher the proportion of institutional ownership, the lower the excess cash holdings. Informational transparancy, as one of the requirements of good corporate governance, can in fact lower the chance of aggrevating the manager’s behavior to practice excess cash holdings that can lower the company’s efficiency.

  8. Prospektive Entwicklung des postoperativen Sprachverstehens nach Tympanoplastik bei chronischer Otitis media

    OpenAIRE

    Knof, B; Plotz, K; Krack, A; Stumper, J; Schönfeld, R

    2013-01-01

    Einleitung: Tympanoplastiken I/III bei chron. Otitis media COM (mesotympanalis CMOM und epitympanalis CEOM). In der Literatur werden erfolgreiche operative Behandlungen mit Verringerung der Schallleitungskomponente (air-bone gap) belegt (Gierke et al. 2011). Aus Sicht des Patienten steht die Verbesserung des Hörvermögens und des Sprachverstehens im Alltag im Vordergrund. Das Ziel war die Untersuchung der Entwicklung des Hörvermögens in Ruhe sowie im Störgeräusch.Methoden: An den Hör- und Sp...

  9. A auditoria externa e as demonstrações contábeis no direito comercial

    OpenAIRE

    Alexandre Demetrius Pereira

    2010-01-01

    A auditoria externa de demonstrações contábeis é um dos instrumentos mais importantes para o desenvolvimento do mercado, pelo fato de adicionar credibilidade e segurança às informações financeiras prestadas pelos agentes econômicos que buscam captar recursos junto ao público investidor. A doutrina jurídica pátria, entretanto, ao contrário do que ocorre em outros países, tem relegado o estudo do assunto a um papel secundário, quase não abordado nas obras nacionais, deixando sua pormenorização ...

  10. Reflexos Contábeis no Novo Código Civil de 2002

    Directory of Open Access Journals (Sweden)

    Ildefonso Assing

    2003-07-01

    Full Text Available Através do presente trabalho, visa-se apresentar aos contabilistas e demais interessados na área contábil, as principais alterações, práticas e teóricas, a respeito do exercício das funções contábeis no novo código civil de 2002. Para facilitar o entendimento dos artigos inerentes à função, menciona-se o artigo e comenta-se o mesmo, a fim de posicionar o interessado no contexto atual.

  11. Valuasi Harga Wajar Saham Sektor Perbankan Yang Go Public Di BEI

    OpenAIRE

    Khairi, Sherly Emita

    2011-01-01

    Investment on stock needs analyisis about valuation of stocks to calculate the intrinsic value of each stocks based on the its fundamental data. The aim of this research is to calculate the intrinsic stock prices of the two company which included in financial sectors and to see whether the stocks of the companies is in the undervalued or overvalued conditions. This research takes samples of financial sectors which are got IPO in BEI from 2005 to 2010. As the samples, it is chosen two banks...

  12. Richtungshören bei Senioren mit Hörgeräteversorgung

    OpenAIRE

    Neumayer, T; Baumann, U; Stöver, T; Weißgerber, T

    2015-01-01

    Einleitung: Da die Lebenserwartung weiter ansteigt, muss in Zukunft Erkrankungen und Veränderungen des Alters eine größere Bedeutung zukommen. So gibt es einen deutlichen Anstieg der mittels Hörhilfen zu versorgenden Presbyakusis. Viele Hörgeräte (HG) werden hinter dem Ohr getragen, somit fehlt die richtungsabhängige Filterwirkung der Ohrmuschel. Ziel dieser Studie war die Untersuchung der Richtungshörfähigkeit bei Senioren mit Hörgeräten.Material/Methoden: 40 Probanden im Alter von 76,3 (±...

  13. Fast Registration of Cardiac Perfusion MRI

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Larsson, Henrik B. W.

    2003-01-01

    This abstract presents a novel method for registration of cardiac perfusion MRI sequences. By performing complex analyses of variance and clustering in an annotated training set off-line, our method provides real-time segmentation in an on-line setting. This renders the method feasible for live...... motion-compensation in MR scanners. Changes in image intensity during the bolus passage are modelled by an Active Appearance Model augmented with a cluster analysis of the training set. Preliminary validation carried out using five subjects showed acceptable segmentation accuracy produced very rapidly...

  14. Stress-only myocardial perfusion scintigraphy

    DEFF Research Database (Denmark)

    Ejlersen, June A; May, Ole; Mortensen, Jesper

    2017-01-01

    and no previous coronary artery disease underwent a 2-day stress (exercise)/rest, gated, and attenuation-corrected (AC), 99m-technetium-sestamibi perfusion study, followed by invasive coronary angiography. The stress datasets were evaluated twice by four physicians with two different training levels (expert...... and novice): familiar and unfamiliar with AC. The two experts also made a consensus reading of the integrated stress-rest datasets. The consensus reading and quantitative data from the invasive coronary angiography were applied as reference methods. RESULTS: The sensitivity/specificity were 0...

  15. Reaktive Sauerstoffradikale bei Patienten mit obstruktivem Schlaf-Apnoe-Syndrom und Regulation der Radikalenbildung durch Angiotensin Rezeptoren

    OpenAIRE

    Stemmler, Susanne

    2003-01-01

    Hohe reaktive Sauerstoffradikalkonzentrationen (ROS) führen zu einer Schädigung der Zelle. In dieser Arbeit wurde überprüft, ob Veränderungen von intrazellulären ROS bei Patienten mit obstruktivem Schlaf-Apnoe-Syndrom (OSAS) vorliegen und welchen Einfluß Angiotensin AT-2-Rezeptoren bei der Bildung der ROS haben. Die ROS-Konzentration wurden fluoreszenzspektrophotometrisch in mononukleären Leukozyten bestimmt. Die intrazelluläre ROS-Konzentration stieg spontan und nach Stimulation ...

  16. Verhaltenssymptome bei Kindern im Vorschul- und Schulalter mit Prader-Willi-Syndrom - eine explorative Studie zu ritualisierten Verhaltensformen

    OpenAIRE

    Sarimski, Klaus; Ebner, Sarah; Wördemann, Claudia

    2012-01-01

    Die Eltern von 64 Kindern und Jugendlichen mit Prader-Willi-Syndrom (PWS) beschrieben Verhaltensmerkmale ihrer Kinder in standardisierten Fragebögen. Dazu wurden im frühen Kindesalter die "Temperament and Atypical Behavior Scale", im späteren Kindes- und Jugendalter der "Verhaltensfragebogen bei Entwicklungsstörungen" verwendet. Während sich im frühen Kindesalter nicht mehr Verhaltensauffälligkeiten zeigten als bei anderen Kindern mit kognitiven Beeinträchtigungen, ergaben sich im späteren Al...

  17. Sind Jugendliche "online" besser zu erreichen? Zur Internetnutzung bei Stresspräventionsmaßnahmen für Jugendliche

    OpenAIRE

    Fridrici, Mirko; Beyer, Anke; Lohaus, Arnold

    2008-01-01

    Jugendliche gelten als eine schwierige Zielgruppe für Gesundheitsförderungsangebote. Vor diesem Hintergrund wird der Frage nachgegangen, welche Möglichkeiten und Grenzen sich bei der Nutzung des Internets zur Verbreitung von Angeboten zur Stressprävention ergeben. Dazu werden die Ergebnisse zweier Studien berichtet. In der ersten Studie mit 1.988 Jugendlichen der siebten bis neunten Klasse wurde untersucht, in welchem Ausmaß eine Internetnutzung bei den Schülern verbreitet ist und welchen Ste...

  18. Ensino de notas explicativas nos Cursos de Ciências Contábeis de universidades públicas brasileiras

    OpenAIRE

    Campos, Couto; Lemes, Sirlei

    2013-01-01

    A evidenciação contábil é um dos principais mecanismos utilizados por stakeholders para obterem informações referentes a uma empresa e, com elas, embasarem suas decisões. Entretanto, pesquisas sobre evidenciação contábil têm mostrado a dificuldade das empresas e, por conseguinte, dos profissionais contábeis em elaborar notas explicativas claras e objetivas.  Assim, o objetivo do presente estudo é analisar como os Cursos de Ciências Contábeis das universidades públicas brasileiras preparam seu...

  19. Evaluation of a regional real-time precise positioning system based on GPS/BeiDou observations in Australia

    Science.gov (United States)

    Ding, Wenwu; Tan, Bingfeng; Chen, Yongchang; Teferle, Felix Norman; Yuan, Yunbin

    2018-02-01

    The performance of real-time (RT) precise positioning can be improved by utilizing observations from multiple Global Navigation Satellite Systems (GNSS) instead of one particular system. Since the end of 2012, BeiDou, independently established by China, began to provide operational services for users in the Asia-Pacific regions. In this study, a regional RT precise positioning system is developed to evaluate the performance of GPS/BeiDou observations in Australia in providing high precision positioning services for users. Fixing three hourly updated satellite orbits, RT correction messages are generated and broadcasted by processing RT observation/navigation data streams from the national network of GNSS Continuously Operating Reference Stations in Australia (AUSCORS) at the server side. At the user side, RT PPP is realized by processing RT data streams and the RT correction messages received. RT clock offsets, for which the accuracy reached 0.07 and 0.28 ns for GPS and BeiDou, respectively, can be determined. Based on these corrections, an accuracy of 12.2, 30.0 and 45.6 cm in the North, East and Up directions was achieved for the BeiDou-only solution after 30 min while the GPS-only solution reached 5.1, 15.3 and 15.5 cm for the same components at the same time. A further improvement of 43.7, 36.9 and 45.0 percent in the three directions, respectively, was achieved for the combined GPS/BeiDou solution. After the initialization process, the North, East and Up positioning accuracies were 5.2, 8.1 and 17.8 cm, respectively, for the BeiDou-only solution, while 1.5, 3.0, and 4.7 cm for the GPS-only solution. However, we only noticed a 20.9% improvement in the East direction was obtained for the GPS/BeiDou solution, while no improvements in the other directions were detected. It is expected that such improvements may become bigger with the increasing accuracy of the BeiDou-only solution.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-05-01

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

  1. Isolated limb perfusion: what is the evidence for its use?

    NARCIS (Netherlands)

    Noorda, Eva M.; Vrouenraets, Bart C.; Nieweg, Omgo E.; van Coevorden, Frits; Kroon, Bin B. R.

    2004-01-01

    BACKGROUND: This study was conducted to assess the best available evidence for the use of isolated limb perfusion. METHODS: Following the principles of Evidence-Based Medicine, we reviewed the best available evidence for isolated limb perfusion (ILP) for melanoma and soft tissue sarcoma (STS) of the

  2. Tissue-specific sparse deconvolution for brain CT perfusion.

    Science.gov (United States)

    Fang, Ruogu; Jiang, Haodi; Huang, Junzhou

    2015-12-01

    Enhancing perfusion maps in low-dose computed tomography perfusion (CTP) for cerebrovascular disease diagnosis is a challenging task, especially for low-contrast tissue categories where infarct core and ischemic penumbra usually occur. Sparse perfusion deconvolution has been recently proposed to effectively improve the image quality and diagnostic accuracy of low-dose perfusion CT by extracting the complementary information from the high-dose perfusion maps to restore the low-dose using a joint spatio-temporal model. However the low-contrast tissue classes where infarct core and ischemic penumbra are likely to occur in cerebral perfusion CT tend to be over-smoothed, leading to loss of essential biomarkers. In this paper, we propose a tissue-specific sparse deconvolution approach to preserve the subtle perfusion information in the low-contrast tissue classes. We first build tissue-specific dictionaries from segmentations of high-dose perfusion maps using online dictionary learning, and then perform deconvolution-based hemodynamic parameters estimation for block-wise tissue segments on the low-dose CTP data. Extensive validation on clinical datasets of patients with cerebrovascular disease demonstrates the superior performance of our proposed method compared to state-of-art, and potentially improve diagnostic accuracy by increasing the differentiation between normal and ischemic tissues in the brain. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Hypothermic Machine Perfusion of Kidney Grafts: Which Pressure is Preferred?

    NARCIS (Netherlands)

    Doorschodt, B. M.; Schreinemachers, M. C. J. M.; Behbahani, M.; Florquin, S.; Weis, J.; Staat, M.; Tolba, R. H.

    2011-01-01

    To assess the effect of the perfusion pressure (PP) during machine perfusion (MP) on the preservation quality of kidney grafts, we compared mean PPs of 25 and 30 mmHg using a porcine autotransplantation model. After assessment of the microcirculation, animals underwent left nephrectomy. Thereafter,

  4. Spatio-temporal analysis of blood perfusion by imaging photoplethysmography

    Science.gov (United States)

    Zaunseder, Sebastian; Trumpp, Alexander; Ernst, Hannes; Förster, Michael; Malberg, Hagen

    2018-02-01

    Imaging photoplethysmography (iPPG) has attracted much attention over the last years. The vast majority of works focuses on methods to reliably extract the heart rate from videos. Only a few works addressed iPPGs ability to exploit spatio-temporal perfusion pattern to derive further diagnostic statements. This work directs at the spatio-temporal analysis of blood perfusion from videos. We present a novel algorithm that bases on the two-dimensional representation of the blood pulsation (perfusion map). The basic idea behind the proposed algorithm consists of a pairwise estimation of time delays between photoplethysmographic signals of spatially separated regions. The probabilistic approach yields a parameter denoted as perfusion speed. We compare the perfusion speed versus two parameters, which assess the strength of blood pulsation (perfusion strength and signal to noise ratio). Preliminary results using video data with different physiological stimuli (cold pressure test, cold face test) show that all measures are influenced by those stimuli (some of them with statistical certainty). The perfusion speed turned out to be more sensitive than the other measures in some cases. However, our results also show that the intraindividual stability and interindividual comparability of all used measures remain critical points. This work proves the general feasibility of employing the perfusion speed as novel iPPG quantity. Future studies will address open points like the handling of ballistocardiographic effects and will try to deepen the understanding of the predominant physiological mechanisms and their relation to the algorithmic performance.

  5. Brain perfusion imaging with iodinated amines

    International Nuclear Information System (INIS)

    Kung, H.F.

    1989-01-01

    Traditional nuclear medicine brain study using 99m Tc pertechnetate, glucoheptonate or diethlenetriaminepentacetic acid (DTPA) and planar imaging has experienced a significant decline in the past 10 years. This is mainly due to the introduction of X-ray CT and more recently the nuclear magnetic resonance (NMR) imaging, by which detailed morphology of the brain, including the detection of breakdown of the blood-brain barrier, can be obtained. The nuclear medicine brain imaging is only prescribed as a complementary test when X-ray CT is negative or equivocal and clinical suspicion remains. The attention of nuclear medicine brain imaging has been shifted from the detection of the breakdown of the blood-brain barrier to the study of brain function-perfusion, metabolism, and receptor binding, etc. The functional brain imaging provides diagnostic information usually unattainable by other radiological techniques. In this article, the iodinated amines as brain perfusion imaging agents are reviewed. Potential clinical application of these agents is discussed

  6. A model system for perfusion quantification using FAIR

    DEFF Research Database (Denmark)

    Andersen, Irene Klærke; Sidaros, Karam; Gesmar, Henrik

    2000-01-01

    Flow-sensitive experiments (FAIR) have been performed on a tube-flow phantom in order to validate quantitative perfusion measurements on humans. A straight-forward correspondence between perfusion and bulk-flow is found. It is shown that the flow phantom model only holds when the slice profiles...... of the involved RF pulses are taken into account. A small flow-independent off-set may be present in the data. The off-set is explained by the model. Based on the correspondence between the phantom and the in vivo models, it is shown that the lowest flow values that could be measured in the phantom correspond...... to perfusion values lower than the cortical perfusion in the brain. Thus, the experimental accuracy and the computational methods for quantitative perfusion measurements in vivo can be validated by a tube-flow phantom....

  7. A model system for perfusion quantification using FAIR

    DEFF Research Database (Denmark)

    Andersen, I.K.; Sidaros, Karam; Gesmar, H

    2000-01-01

    Flow-sensitive experiments (FAIR) have been performed on a tube-flow phantom in order to validate quantitative perfusion measurements on humans. A straight-forward correspondence between perfusion and bulk-flow is found. It is shown that the flow phantom model only holds when the slice profiles...... of the involved RF pulses are taken into account. A small flow-independent off-set may be present in the data. The off-set is explained by the model. Based on the correspondence between the phantom and the in vivo models, it is shown that the lowest flow values that could be measured in the phantom correspond...... to perfusion values lower than the cortical perfusion in the brain. Thus, the experimental accuracy and the computational methods for quantitative perfusion measurements in vivo can be validated by a tube-flow phantom...

  8. Clinically relevant incidental cardiovascular findings in CT examinations; Klinisch relevante kardiovaskulaere Zufallsbefunde bei CT-Untersuchungen

    Energy Technology Data Exchange (ETDEWEB)

    Voigt, P.; Fahnert, J.; Kahn, T.; Surov, A. [Universitaetsklinikum Leipzig, Klinik fuer Diagnostische und Interventionelle Radiologie, Leipzig (Germany); Schramm, D.; Bach, A.G. [Universitaetsklinikum Halle (Saale), Klinik fuer Radiologie, Halle (Germany)

    2017-04-15

    Incidental cardiovascular findings are a frequent phenomenon in computed tomography (CT) examinations. As the result of a dedicated PubMed search this article gives a systemic overview of the current literature on the most important incidental cardiovascular findings, their prevalence and clinical relevance. The majority of incidental cardiovascular findings are of only low clinical relevance; however, highly relevant incidental findings, such as aortic aneurysms, thromboses and thromboembolic events can also occasionally be found, especially in oncology patients. The scans from every CT examination should also be investigated for incidental findings as they can be of decisive importance for the further clinical management of patients, depending on their clinical relevance. (orig.) [German] Inzidentelle kardiovaskulaere Befunde sind ein haeufiges Phaenomen bei CT-Untersuchungen. Mit dieser Arbeit soll nach gezielter PubMed-Recherche ein systematischer Literaturueberblick ueber die wichtigsten kardiovaskulaeren Zufallsbefunde sowie deren Haeufigkeit und klinische Relevanz gegeben werden. Die Mehrzahl der inzidentellen kardiovaskulaeren Befunde sind klinisch nur von untergeordneter Bedeutung, allerdings werden immer wieder auch hochgradig relevante Zufallsbefunde wie beispielsweise Aortenaneurysmata oder - gerade bei onkologischen Patienten - Thrombosen und thrombembolische Ereignisse detektiert. Jede CT-Untersuchung sollte gezielt nach inzidentellen Befunden durchsucht werden, da diese je nach klinischer Relevanz von entscheidender Bedeutung fuer das weitere klinische Management des Patienten sein koennen. (orig.)

  9. Comparison of Ultra-Rapid Orbit Prediction Strategies for GPS, GLONASS, Galileo and BeiDou

    Directory of Open Access Journals (Sweden)

    Tao Geng

    2018-02-01

    Full Text Available Currently, ultra-rapid orbits play an important role in the high-speed development of global navigation satellite system (GNSS real-time applications. This contribution focuses on the impact of the fitting arc length of observed orbits and solar radiation pressure (SRP on the orbit prediction performance for GPS, GLONASS, Galileo and BeiDou. One full year’s precise ephemerides during 2015 were used as fitted observed orbits and then as references to be compared with predicted orbits, together with known earth rotation parameters. The full nine-parameter Empirical Center for Orbit Determination in Europe (CODE Orbit Model (ECOM and its reduced version were chosen in our study. The arc lengths of observed fitted orbits that showed the smallest weighted root mean squares (WRMSs and medians of the orbit differences after a Helmert transformation fell between 40 and 45 h for GPS and GLONASS and between 42 and 48 h for Galileo, while the WRMS values and medians become flat after a 42 h arc length for BeiDou. The stability of the Helmert transformation and SRP parameters also confirmed the similar optimal arc lengths. The range around 42–45 h is suggested to be the optimal arc length interval of the fitted observed orbits for the multi-GNSS joint solution of ultra-rapid orbits.

  10. Bedeutung einer Supplementation bei Osteopenie mit einer Kombination aus Kalzium und Vitamin D

    Directory of Open Access Journals (Sweden)

    Kudlacek S

    2005-01-01

    Full Text Available Sowohl Vitamin D als auch Kalzium werden für den gesunden Knochenstoffwechsel in ausreichender Konzentration benötigt. Die erhobenen Normwerte für die tägliche Aufnahme sind mit der Nahrung kaum abzudecken und die Regulationsmechanismen von Parathormon führen zur Osteoporose. Bisher ist, abgesehen vom Knochenstoffwechsel, eine Reihe von chronischen Erkrankungen bekannt, die wahrscheinlich mit einer Hypovitaminose D in Zusammenhang stehen. Da derzeit in den überwiegenden Studien die gezielte Supplementation von Vitamin D und Kalzium einen nachweisbaren Effekt zeigte oder zumindest fixer Bestandteil des Therapieregimes ist, kann die derzeit praktizierte Applikation als Standard gelten. Einen positiven Effekt auf Frakturdaten zeigte auch die kürzlich veröffentlichte Metaanalyse, allerdings bei einer Dosierung von 700–800 IU. Da eindeutige Vitamin-D-Defizite in der gesunden Bevölkerung nachweisbar sind, sollte Vitamin D vermehrt appliziert werden, sei es durch Sonne, Ernährung oder auch mittels Supplementation. Wünschenswert ist allerdings zukünftig eine Vitamin D-Anreicherung von Nahrungsmitteln, z. B. Milch. Somit könnte zumindest bei Risikogruppen, wie es Altenheimbewohner sind, eine den Richtlinien entsprechende Versorgung gewährleistet werden.

  11. Pediatric radiological diagnostics in suspected child abuse; Kinderradiologische Diagnostik bei Verdacht auf Kindesmisshandlung

    Energy Technology Data Exchange (ETDEWEB)

    Erfurt, C.; Schmidt, U. [Technische Universitaet Dresden, Institut fuer Rechtsmedizin, Medizinische Fakultaet, Dresden (Germany); Hahn, G. [Universitaetsklinikum Carl Gustav Carus, Dresden, Abteilung Kinderradiologie, Institut und Poliklinik fuer Radiologische Diagnostik, Dresden (Germany); Roesner, D. [Universitaetsklinikum Carl Gustav Carus, Dresden, Klinik und Poliklinik fuer Kinderchirurgie, Dresden (Germany)

    2009-10-15

    Advanced and specialized radiological diagnostics are essential in the case of clinical suspicion of pediatric injuries to the head, thorax, abdomen, and extremities when there is no case history or when ''battered child syndrome'' is assumed on the basis of inadequate trauma. In particular, the aim of this sophisticated diagnostic procedure is the detection of lesions of the central nervous system (CNS) in order to initiate prompt medical treatment. If diagnostic imaging shows typical findings of child abuse, accurate documented evidence of the diagnostic results is required to prevent further endangerment of the child's welfare. (orig.) [German] Klinisch diagnostizierte Verletzungen an Kopf, Thorax, Abdomen oder Extremitaeten eines Kindes bei scheinbar leerer Anamnese oder Angabe eines inadaequaten Traumas erfordern beim Verdacht auf ein Battered-Child-Syndrom eine erweiterte und spezialisierte radiologische Diagnostik. Diese soll insbesondere im Bereich des ZNS Verletzungsfolgen erfassen, um therapeutische Massnahmen einleiten zu koennen. Bei typischen, auf eine Misshandlung hinweisenden radiologischen Befunden ist eine praezise beweissichere Befunddokumentation erforderlich, um eine weitere Kindeswohlgefaehrdung zu vermeiden. (orig.)

  12. Radiotherapy for solitary plasmacytoma and multiple myeloma; Strahlentherapie bei solitaerem Plasmozytom und multiplem Myelom

    Energy Technology Data Exchange (ETDEWEB)

    Schmaus, M.C. [Universitaetsklinikum Heidelberg, Klinik fuer Radioonkologie und Strahlentherapie, Heidelberg (Germany); Neuhof, D. [MVZ Strahlentherapie und Nuklearmedizin Weinheim, Weinheim (Germany)

    2014-06-15

    Solitary plasmacytoma and multiple myeloma require a differentiated radiotherapy. The irradiation for plasmacytoma with an adequate total dose (medullary 40-50 Gy or extramedullary 50-60 Gy) leads to a high degree of local control with a low rate of side effects. In cases of multiple myeloma radiotherapy will achieve effective palliation, both in terms of recalcification as well as reduction of neurological symptoms and analgesia. In terms of analgesia the rule is the higher the single dose fraction the faster the reduction of pain. As part of a conditioning treatment prior to stem cell transplantation radiotherapy contributes to the establishment of a graft versus myeloma effect (GVM). (orig.) [German] Das solitaere Plasmozytom und das multiple Myelom fordern eine differenzierte Strahlenbehandlung. Bei Plasmozytomen fuehrt eine Bestrahlung mit ausreichender Gesamtdosis (medullaer 40-50 Gy oder extramedullaer 50-60 Gy) zu einer hohen Lokalkontrolle mit einer geringen Rate an Nebenwirkungen. Beim multiplen Myelom kann die Strahlentherapie eine effektive Palliation sowohl hinsichtlich Rekalzifikation als auch Reduktion neurologischer Symptomatik und Analgesie erzielen. Hinsichtlich der Analgesie gilt: Je hoeher die Einzeldosis, desto schneller der Wirkeintritt. Im Rahmen einer Konditionierungstherapie vor Stammzelltransplantation traegt die Strahlentherapie zur Etablierung eines Graft-versus-Myelom-Effekts (GvM) bei. (orig.)

  13. Comparison of Ultra-Rapid Orbit Prediction Strategies for GPS, GLONASS, Galileo and BeiDou.

    Science.gov (United States)

    Geng, Tao; Zhang, Peng; Wang, Wei; Xie, Xin

    2018-02-06

    Currently, ultra-rapid orbits play an important role in the high-speed development of global navigation satellite system (GNSS) real-time applications. This contribution focuses on the impact of the fitting arc length of observed orbits and solar radiation pressure (SRP) on the orbit prediction performance for GPS, GLONASS, Galileo and BeiDou. One full year's precise ephemerides during 2015 were used as fitted observed orbits and then as references to be compared with predicted orbits, together with known earth rotation parameters. The full nine-parameter Empirical Center for Orbit Determination in Europe (CODE) Orbit Model (ECOM) and its reduced version were chosen in our study. The arc lengths of observed fitted orbits that showed the smallest weighted root mean squares (WRMSs) and medians of the orbit differences after a Helmert transformation fell between 40 and 45 h for GPS and GLONASS and between 42 and 48 h for Galileo, while the WRMS values and medians become flat after a 42 h arc length for BeiDou. The stability of the Helmert transformation and SRP parameters also confirmed the similar optimal arc lengths. The range around 42-45 h is suggested to be the optimal arc length interval of the fitted observed orbits for the multi-GNSS joint solution of ultra-rapid orbits.

  14. Kyphoplasty and vertebroplasty for spinal trauma; Kyphoplastie und Vertebroplastie bei Wirbelsaeulentraumata

    Energy Technology Data Exchange (ETDEWEB)

    Ahlhelm, F. [Kantonsspital Baden AG, Abteilung fuer Neuroradiologie, Institut fuer Radiologie, Baden (Switzerland); Omidi, R. [Kantonsspital Baden AG, Interventionelle Radiologie, Institut fuer Radiologie, Baden (Switzerland)

    2016-08-15

    Minimally invasive treatment of spinal fractures. Conservative treatment versus spinal surgery. Minimally invasive stabilization techniques, such as percutaneous (assisted) cementoplasty have been introduced as new procedures. Magnetic resonance imaging (MRI), X-rays and computed tomography (CT) are the imaging techniques of first choice. The most important questions concern recent fractures, instability and indications for minimally invasive treatment. Vertebroplasty and kyphoplasty are established methods for the treatment of patients with osteoporosis. Cementoplasty techniques are promising treatment options for traumatic spinal injuries. The application of the techniques should best be carried out in individual cases within the framework of prospective controlled studies. (orig.) [German] Minimal-invasive Behandlung von Wirbelsaeulentraumata. Konservative Behandlung vs. Wirbelsaeulenchirurgie. Als neue Verfahren wurden minimal-invasive Stabilisationstechniken, z. B. perkutane (assistierte) Zementoplastien eingefuehrt. Roentgen, MRT und CT sind die bildgebenden Verfahren der ersten Wahl. Die wichtigsten Fragestellungen sind: Frische Fraktur? Instabilitaet? Indikation fuer minimal-invasive Behandlung ?Vertebroplastie und Kyphoplastie sind bei Osteoporosepatienten etabliert. Bei Wirbelsaeulentraumata sind Zementoplastietechniken vielversprechende Therapieoptionen. Die Anwendung der Techniken sollte im individuellen Fall am besten im Rahmen prospektiver kontrollierter Studien erfolgen. (orig.)

  15. Comparison of Ultra-Rapid Orbit Prediction Strategies for GPS, GLONASS, Galileo and BeiDou

    Science.gov (United States)

    Zhang, Peng; Wang, Wei; Xie, Xin

    2018-01-01

    Currently, ultra-rapid orbits play an important role in the high-speed development of global navigation satellite system (GNSS) real-time applications. This contribution focuses on the impact of the fitting arc length of observed orbits and solar radiation pressure (SRP) on the orbit prediction performance for GPS, GLONASS, Galileo and BeiDou. One full year’s precise ephemerides during 2015 were used as fitted observed orbits and then as references to be compared with predicted orbits, together with known earth rotation parameters. The full nine-parameter Empirical Center for Orbit Determination in Europe (CODE) Orbit Model (ECOM) and its reduced version were chosen in our study. The arc lengths of observed fitted orbits that showed the smallest weighted root mean squares (WRMSs) and medians of the orbit differences after a Helmert transformation fell between 40 and 45 h for GPS and GLONASS and between 42 and 48 h for Galileo, while the WRMS values and medians become flat after a 42 h arc length for BeiDou. The stability of the Helmert transformation and SRP parameters also confirmed the similar optimal arc lengths. The range around 42–45 h is suggested to be the optimal arc length interval of the fitted observed orbits for the multi-GNSS joint solution of ultra-rapid orbits. PMID:29415467

  16. Global Ionospheric Modelling using Multi-GNSS: BeiDou, Galileo, GLONASS and GPS.

    Science.gov (United States)

    Ren, Xiaodong; Zhang, Xiaohong; Xie, Weiliang; Zhang, Keke; Yuan, Yongqiang; Li, Xingxing

    2016-09-15

    The emergence of China's Beidou, Europe's Galileo and Russia's GLONASS satellites has multiplied the number of ionospheric piercing points (IPP) offered by GPS alone. This provides great opportunities for deriving precise global ionospheric maps (GIMs) with high resolution to improve positioning accuracy and ionospheric monitoring capabilities. In this paper, the GIM is developed based on multi-GNSS (GPS, GLONASS, BeiDou and Galileo) observations in the current multi-constellation condition. The performance and contribution of multi-GNSS for ionospheric modelling are carefully analysed and evaluated. Multi-GNSS observations of over 300 stations from the Multi-GNSS Experiment (MGEX) and International GNSS Service (IGS) networks for two months are processed. The results show that the multi-GNSS GIM products are better than those of GIM products based on GPS-only. Differential code biases (DCB) are by-products of the multi-GNSS ionosphere modelling, the corresponding standard deviations (STDs) are 0.06 ns, 0.10 ns, 0.18 ns and 0.15 ns for GPS, GLONASS, BeiDou and Galileo, respectively in satellite, and the STDs for the receiver are approximately 0.2~0.4 ns. The single-frequency precise point positioning (SF-PPP) results indicate that the ionospheric modelling accuracy of the proposed method based on multi-GNSS observations is better than that of the current dual-system GIM in specific areas.

  17. Negative pressure ventilation enhances acinar perfusion in isolated rat lungs.

    Science.gov (United States)

    Watson, Kal E; Segal, Gilad S; Conhaim, Robert L

    2018-01-01

    We compared acinar perfusion in isolated rat lungs ventilated using positive or negative pressures. The lungs were ventilated with air at transpulmomary pressures of 15/5 cm H 2 O, at 25 breaths/min, and perfused with a hetastarch solution at P pulm art /P LA pressures of 10/0 cm H 2 O. We evaluated overall perfusability from perfusate flows, and from the venous concentrations of 4-µm diameter fluorescent latex particles infused into the pulmonary circulation during perfusion. We measured perfusion distribution from the trapping patterns of those particles within the lung. We infused approximately 9 million red fluorescent particles into each lung, followed 20 min later by an infusion of an equal number of green particles. In positive pressure lungs, 94.7 ± 2.4% of the infused particles remained trapped within the lungs, compared to 86.8 ± 5.6% in negative pressure lungs ( P ≤ 0.05). Perfusate flows averaged 2.5 ± 0.1 mL/min in lungs ventilated with positive pressures, compared to 5.6 ± 01 mL/min in lungs ventilated with negative pressures ( P ≤ 0.05). Particle infusions had little effect on perfusate flows. In confocal images of dried sections of each lung, red and green particles were co-localized in clusters in positive pressure lungs, suggesting that acinar vessels that lacked particles were collapsed by these pressures thereby preventing perfusion through them. Particles were more broadly and uniformly distributed in negative pressure lungs, suggesting that perfusion in these lungs was also more uniformly distributed. Our results suggest that the acinar circulation is organized as a web, and further suggest that portions of this web are collapsed by positive pressure ventilation.

  18. Value of chest X-ray combined with perfusion scan versus ventilation/perfusion scan in acute pulmonary embolism

    NARCIS (Netherlands)

    de Groot, M. R.; Turkstra, F.; van Marwijk Kooy, M.; Oostdijk, A. H.; van Beek, E. J.; Büller, H. R.

    2000-01-01

    The main purpose of ventilation scanning, as adjunct to perfusion lung scintigraphy, in acute pulmonary embolism is to allow for the classification of segmental perfusion defects as mismatched, which is generally accepted as proof for the presence of pulmonary embolism. We examined whether this

  19. Determination of an adequate perfusion pressure for continuous dual vessel hypothermic machine perfusion of the rat liver

    NARCIS (Netherlands)

    't Hart, Nils A.; der van Plaats, Arjan; Leuvenink, Henri G. D.; van Goor, Harry; Wiersema-Buist, Janneke; Verkerke, Gijsbertus J.; Rakhorst, Gerhard; Ploeg, Rutger J.

    Hypothermic machine perfusion (HMP) provides better protection against ischemic damage of the kidney compared to cold-storage. The required perfusion pressures needed for optimal HMP of the liver are, however, unknown. Rat livers were preserved in University of Wisconsin organ preservation solution

  20. 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.)

  1. Perfusion vector - a new method to quantify myocardial perfusion scintigraphy images: a simulation study with validation in patients

    DEFF Research Database (Denmark)

    Minarik, David; Senneby, Martin; Wollmer, Per

    2015-01-01

    Background The interpretation of myocardial perfusion scintigraphy (MPS) largely relies on visual assessment by the physician of the localization and extent of a perfusion defect. The aim of this study was to introduce the concept of the perfusion vector as a new objective quantitative method...... for further assisting the visual interpretation and to test the concept using simulated MPS images as well as patients. Methods The perfusion vector is based on calculating the difference between the anatomical centroid and the perfusion center of gravity of the left ventricle. Simulated MPS images were.......001) but not for patients with infarction. The correlation between the defect size and stress vector magnitude was also found to be significant (p assisting the visual interpretation in MPS studies. Further...

  2. Qualidade das informações contábeis na oferta pública de ações e debêntures pelas companhias abertas brasileiras

    Directory of Open Access Journals (Sweden)

    Edilson Paulo

    2012-01-01

    Full Text Available Apesar de as debêntures apresentarem maior volume de negociações no ambiente brasileiro, grande parte das pesquisas nacionais sobre a qualidade das informações contábeis tem focado no mercado de ações. Considerando-se que diversos estudos sugerem que o ambiente institucional e organizacional das firmas afeta o comportamento dos números contábeis, pode-se levantar o seguinte problema de pesquisa: A qualidade das informações contábeis é afetada significativamente pela oferta pública de ações e debêntures? O objetivo deste trabalho é analisar a qualidade das informações contábeis na oferta pública de ações e debêntures por companhias abertas brasileiras, com o intuito de verificar se existem diferenças significativas nos números contábeis. Para atingir o propósito deste trabalho, desenvolveu-se uma pesquisa empírica, com uma amostra formada por empresas que efetuaram ofertas públicas entre 2000 e 2006. Os resultados evidenciam que a oferta pública não afeta, significativamente, os números contábeis, sugerindo, assim, que a qualidade das informações contábeis não é influenciada pela emissão de ações e debêntures.

  3. Europe CERN recherche - Pret de 300 millions d'euros de la BEI pour l'accelerateur de particules

    CERN Multimedia

    2002-01-01

    "La Banque europeenne d'investissement (BEI) va preter 300 millions d'euros pour financer la phase finale de la construction du grand accelerateur de particules LHC (Large Hadron Collider) du CERN, a indique jeudi l'organisation europeenne pour la recherche nucleaire" (1/2 page).

  4. Von der Straße ins Labor: Die Modifikation der Sprachproduktion bei lauten Fahrgeräuschen

    DEFF Research Database (Denmark)

    Landgraf, Rabea; Niebuhr, Oliver; Schmidt, Gerhard

    2015-01-01

    entstehende Lombard-Sprache unter kontrollierten Laborbedingungen nachgebildet und somit im Labor möglichst realitätsnah untersucht werden kann, wurde eine an der Universität Kiel entwickelte akustische Umgebungssimulation verwendet. In dieser Laborsituation sowie während einer echten Fahrsituation wurden bei...... Labor und im fahrenden Auto auftretende Lombard-Effekt qualitativ gleich ist....

  5. USER'S GUIDE TO THE PERSONAL COMPUTER VERSION OF THE BIOGENIC EMISSIONS INVENTORY SYSTEM (PC-BEIS2)

    Science.gov (United States)

    The document is a user's guide for an updated Personal Computer version of the Biogenic Emissions Inventory System (PC-BEIS2), allowing users to estimate hourly emissions of biogenic volatile organic compounds (BVOCs) and soil nitrogen oxide emissions for any county in the contig...

  6. Solution Method and Precision Analysis of Double-difference Dynamic Precise Orbit Determination of BeiDou Navigation Satellite System

    Directory of Open Access Journals (Sweden)

    LIU Weiping

    2016-02-01

    Full Text Available To resolve the high relativity between the transverse element of GEO orbit and double-difference ambiguity, the classical double-difference dynamic method is improved and the method, which is to determine precise BeiDou satellite orbit using carrier phase and pseudo-range smoothed by phase, is proposed. The feasibility of the method is discussed and the influence of the method about ambiguity fixing is analyzed. Considering the characteristic of BeiDou, the method, which is to fix double-difference ambiguity of BeiDou satellites by QIF, is derived. The real data analysis shows that the new method, which can reduce the relativity and assure the precision, is better than the classical double-difference dynamic method. The result of ambiguity fixing is well by QIF, but the ambiguity fixing success rate is not high on the whole. So the precision of BeiDou orbit can't be improved clearly after ambiguity fixing.

  7. Intra-Arterial MR Perfusion Imaging of Meningiomas: Comparison to Digital Subtraction Angiography and Intravenous MR Perfusion Imaging.

    Directory of Open Access Journals (Sweden)

    Mark A Lum

    Full Text Available To evaluate the ability of IA MR perfusion to characterize meningioma blood supply.Studies were performed in a suite comprised of an x-ray angiography unit and 1.5T MR scanner that permitted intraprocedural patient movement between the imaging modalities. Patients underwent intra-arterial (IA and intravenous (IV T2* dynamic susceptibility MR perfusion immediately prior to meningioma embolization. Regional tumor arterial supply was characterized by digital subtraction angiography and classified as external carotid artery (ECA dural, internal carotid artery (ICA dural, or pial. MR perfusion data regions of interest (ROIs were analyzed in regions with different vascular supply to extract peak height, full-width at half-maximum (FWHM, relative cerebral blood flow (rCBF, relative cerebral blood volume (rCBV, and mean transit time (MTT. Linear mixed modeling was used to identify perfusion curve parameter differences for each ROI for IA and IV MR imaging techniques. IA vs. IV perfusion parameters were also directly compared for each ROI using linear mixed modeling.18 ROIs were analyzed in 12 patients. Arterial supply was identified as ECA dural (n = 11, ICA dural (n = 4, or pial (n = 3. FWHM, rCBV, and rCBF showed statistically significant differences between ROIs for IA MR perfusion. Peak Height and FWHM showed statistically significant differences between ROIs for IV MR perfusion. RCBV and MTT were significantly lower for IA perfusion in the Dural ECA compared to IV perfusion. Relative CBF in IA MR was found to be significantly higher in the Dural ICA region and MTT significantly lower compared to IV perfusion.

  8. Pulmonary artery perfusion versus no perfusion during cardiopulmonary bypass for open heart surgery in adults

    DEFF Research Database (Denmark)

    Buggeskov, Katrine B; Grønlykke, Lars; Risom, Emilie C

    2018-01-01

    handsearched retrieved study reports and scanned citations of included studies and relevant reviews to ensure that no relevant trials were missed. We searched for ongoing trials and unpublished trials in the World Health Organization International Clinical Trials Registry Platform (ICTRP) and at clinicaltrials...... of mortality, pulmonary events, serious adverse events (SAEs), and increased inflammatory markers for adult surgical patients. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Science Citation Index Expanded, and advanced Google for relevant studies. We......). We used GRADE principles to assess the quality of evidence. MAIN RESULTS: We included in this review four RCTs (210 participants) reporting relevant outcomes. Investigators randomly assigned participants to pulmonary artery perfusion with blood versus no perfusion during CPB. Only one trial included...

  9. First results of concurrent preoperative radiochemotherapy of locally advanced rectal cancer; Erste Ergebnisse der neoadjuvanten simultanen Radiochemotherapie bei fortgeschrittenen Rektumkarzinomen

    Energy Technology Data Exchange (ETDEWEB)

    Kuechenmeister, U.; Klautke, G.; Muecke, R.; Fietkau, R. [Rostock Univ. (Germany). Klinik und Poliklinik fuer Strahlentherapie; Kirchner, R.; Mellert, J.; Hopt, U.T. [Rostock Univ. (Germany). Klinik und Poliklinik fuer Chirurgie

    2000-12-01

    Between May 1997 and November 1999 22 patients were treated with preoperative radiochemotherapy. A total dose of 45 Gy with a small-volume boost of 5.4 Gy was delivered in conventional fractionation (single dose 1,8 Gy). On days 1 to 5 and 29 to 33 patients received concurrently 5-fluorouracil (5-FU) as continuous infusion of 1,000 mg/m{sup 2}. If there was any sign of cardiac toxicity chemotherapy was changed to 5-FU/folinic acid or ralitrexed. Results: Surgery following radiochemotherapy was performed in 19/22 patients. Resections with negative margins were achieved in 16/19 (84%) patients. Sphincter-conserving surgery was possible in 9/19 (47%) patients. A downstaging of at least 1 T category was found in 12/19 (63%) patients. With a median follow-up of 16 months no locoregional recurrences occurred in patients who underwent surgery. Two-year disease-free survival of resected patients is 62%, 2-year overall survival in 89%, of the whole population 76%. (orig.) [German] Vom 1.5.1997 bis 30.11.1999 wurden bei 22 Patienten eine neoadjuvante Radiochemotherapie durchgefuehrt. Appliziert wurde eine Dosis von 45 Gy zuzueglich eines Boostes von 5,4 Gy. In der ersten und fuenften Bestrahlungswoche erhielten die Patienten an fuenf aufeinander folgenden Tagen eine Dosis von taeglich 1000 mg/m{sup 2} 5-FU als intravenoese Dauerinfusion ueber 24 Stunden. Bei auftretender Kardiotoxizitaet wurde die Chemotherapie auf 5-FU-Bolusinfusion oder Ralitrexed umgestellt. Ergebnisse: 19/22 Patienten konnten einer Operation zugefuehrt werden. Bei 16/19 (84%) der operierten Patienten konnte eine R0-Resektion erreicht werden. Eine funktionserhaltende Behandlung war bei 9/19 (47%) Patienten moeglich. Ein Downstaging um mindestens eine T-Kategorie wurde bei 12/19 (63%) Patienten erzielt. Bei einer medianen Nachbeobachtungszeit von 16 Monaten ist bisher kein lokales Rezidiv bei den operierten Patienten aufgetreten. Das progressionsfreie Ueberleben der operierten Patienten (R0/R1) betraegt

  10. Myocardial CT perfusion imaging for ischemia detection

    Science.gov (United States)

    Capunay, Carlos

    2017-01-01

    Coronary computed tomography angiography (CCTA) plays an important role in many specific scenarios such as in symptomatic patients with intermediate pretest of coronary artery disease (CAD), as well as in the triage of patients with acute chest pain with TIMI risk ≤2. However, it cannot detect the presence of associated ischemia, which is critical for clinical decision making among patients with moderate to severe stenosis. Although functional information can be obtained with different non-invasive tools, cardiac CT is the unique modality that can perform a comprehensive evaluation of coronary anatomy plus the functional significance of lesions. Myocardial CT perfusion (CTP) can be performed with different approaches such as static and dynamic CTP. In addition, static CTP can be performed using single energy CT (SECT) or dual energy CT (DECT). In this review, we will discuss the technical parameters and the available clinical evidence of static CTP using both SECT and DECT. PMID:28540208

  11. Perfusion computed tomography evaluation of angiogenesis in liver cancer.

    Science.gov (United States)

    Yang, Han Feng; Du, Yong; Ni, Jia Xiang; Zhou, Xiang Ping; Li, Jin Dong; Zhang, Qing; Xu, Xiao Xue; Li, Yang

    2010-06-01

    To investigate the value of computed tomography (CT) perfusion imaging for assessment of angiogenesis in liver cancer. Twenty-one patients with histologically proven liver cancer underwent CT perfusion examination. We compared the following perfusion parameters in the tumour area versus the non-tumour area: total blood flow (TBF), hepatic arterial perfusion (HAP), hepatic portal perfusion (HPP) and hepatic arterial perfusion index (HAPI). Slices of postoperative specimen were stained with haematoxylin-eosin and anti-CD34 immunohistochemistry. The slices were evaluated with emphasis on the CD34-positive neovasculature in the tumour parenchyma. Tumour microvascular density (MVD) was calculated according to the Weidner method. Pearson correlation was used to detect correlations between tumour MVD and tumour perfusion parameters. TBF and HPP in the tumour area were lower than in the non-tumour area (P HAP and HAPI in the tumour area were higher than those of the non-tumour area (P HAP in the tumour area correlated with MVD in the tumour (P cancer. TBF or HAP may be a useful parameter in assessing angiogenesis of liver cancer.

  12. Non-invasive MR perfusion study in patients with depression

    International Nuclear Information System (INIS)

    Lv Su; Huang Xiaoqi; Zou Ling; Li Dongming; Tang Hehan; Yang Hong; Zhang Tijiang; Li Xiuli; Gong Qiyong; Sun Xueli; Zou Ke

    2009-01-01

    Objective: To investigate the brain perfusion changes in patients with refractory depressive disorder (RDD) and non-refractory depressive disorder (NDD) using arterial spin labeling (ASL). Methods: Present study included 12 patients with RDD, 37 patients with NDD and 42 controls, and their age, sex and handedness were matched among the three groups. FAIR sequences were performed using a 3 T MR imaging system with an 8 channel phase array head coil. The labelled and controled images were subtracted and then averaged to obtain perfusion-weighted images. The first 2 images were excluded to avoid T 1 equilibrium effects and then voxel based analysis was performed using SPM2. One way ANOVA analysis using age as covariance (thresholded at P<0.01 uncorrected) was performed. Results: Patients with NDD showed regional alteration of the brain perfusion, mainly involved in two frontal- subcortical circuits, i.e. significantly decreased perfusion in the left frontal and thalamus (the limbic- thalamo-cortical circuit) whereas significantly increased perfusion in bilateral hippocampi, right lentiform and left anterior cingulated gyms (the limbic-striatal-pallidal-thalamic circuit). In contrast, patients with RDD presented significantly decreased perfusion involving bilateral frontal areas (the limbic-thalamo-cortical circuit) whereby no significantly increased perfusion areas were observed. Conclusion: In addition to the reported experimental evidences, our results suggest that the RDD is associated with inactivity of bilateral frontal areas, while the NDD is associated with inactivity of left frontal areas and overaetivity of bilateral limbic system. (authors)

  13. Radiological contrast media and pancreatic blood perfusion in anesthetized rats.

    Science.gov (United States)

    Linder, G; Carlsson, P O; Källskog, Ö; Hansell, P; Jansson, L; Riesenfeld Källskog, V

    2007-12-01

    Radiological contrast media (CM) have been suggested to be able to impair pancreatic microcirculation. To evaluate the effects of an iso-osmolar (iodixanol, 290 mOsm/kg H2O) and a low-osmolar (iopromide, 660 mOsm/kg H2O) CM on total pancreatic and islet blood perfusion. Thiobutabarbital-anesthetized rats were injected with iodine equivalent doses (600 mg I/kg body weight) of iodixanol or iopromide. Saline or low-osmolar mannitol (660 mOsm/kg H2O) solutions served as control substances. Blood perfusion measurements were then carried out with a microsphere technique. Iso-osmolar iodixanol had no effects on blood perfusion. Low-osmolar iopromide increased total pancreatic blood perfusion, whereas islet blood perfusion was unchanged. No differences were seen when mannitol solutions were given. Neither an iso-osmolar nor a low-osmolar CM affected pancreatic islet blood perfusion, whereas the low-osmolar CM increased total pancreatic blood perfusion. The absence of hemodynamic effect of low-osmolar mannitol suggests that the hyperosmolality per se of iopromide versus iodixanol does not induce the hemodynamic effect. The consequences of the effect of iopromide for pancreatic function remain to be established.

  14. Low dose CT perfusion using k-means clustering

    Science.gov (United States)

    Pisana, Francesco; Henzler, Thomas; Schönberg, Stefan; Klotz, Ernst; Schmidt, Bernhard; Kachelrieß, Marc

    2016-03-01

    We aim at improving low dose CT perfusion functional parameters maps and CT images quality, preserving quantitative information. In a dynamic CT perfusion dataset, each voxel is measured T times, where T is the number of acquired time points. In this sense, we can think about a voxel as a point in a T-dimensional space, where the coordinates of the voxels would be the values of its time attenuation curve (TAC). Starting from this idea, a k-means algorithm was designed to group voxels in K classes. A modified guided time-intensity profile similarity (gTIPS) filter was implemented and applied only for those voxels belonging to the same class. The approach was tested on a digital brain perfusion phantom as well as on clinical brain and body perfusion datasets, and compared to the original TIPS implementation. The TIPS filter showed the highest CNR improvement, but lowest spatial resolution. gTIPS proved to have the best combination of spatial resolution and CNR improvement for CT images, while k-gTIPS was superior to both gTIPS and TIPS in terms of perfusion maps image quality. We demonstrate k-means clustering analysis can be applied to denoise dynamic CT perfusion data and to improve functional maps. Beside the promising results, this approach has the major benefit of being independent from the perfusion model employed for functional parameters calculation. No similar approaches were found in literature.

  15. Ventilation and ventilation/perfusion ratios

    International Nuclear Information System (INIS)

    Valind, S.O.

    1989-01-01

    The thesis is based on five different papers. The labelling of specific tracer compounds with positron emitting radionuclides enables a range of structural, physiological and biochemical parameters in the lung to be measured non-invasively, using positron emission tomography. This concept affords a unique opportunity for in vivo studies of different expressions of pulmonary pathophysiology at the regional level. The present thesis describes the application of positron emission tomography to the measurements of ventilation and ventilation/perfusion ratios using inert gas tracers, neon-19 and nitrogen-13 respectively. The validity of the methods applied was investigated with respect to the transport of inert gas tracers in the human lung. Both ventilation and the ventilation/perfusion ratio may be obtained with errors less than 10 % in the normal lung. In disease, however, errors may increase in those instances where the regional ventilation is very low or the intra-regional gas flow distribution is markedly nonuniform. A 2-3 fold increase in ventilation was demonstrated in normal nonsmoking subjects going from ventral to dorsal regions in the supine posture. These large regional differences could be well explained by the intrinsic elastic properties of lung tissue, considering the gravitational gradient in transpulmonary pressure. In asymptomatic smokers substantial regional ventilatroy abnormalities were found whilst the regional gas volume was similar in smokers and nonsmokers. The uncoupling between ventilation and gas volume probably reflects inflammatory changes in the airways. The regional differences in dV/dt/dQ/dt were relatively small and blood flow was largely matched to ventilation in the supine posture. However, small regions of lung with very low ventilation, unmatched by blood flow commonly exists in the most dependent parts of the lung in both smokers and nonsmokers. (29 illustrations, 7 tables, 113 references)

  16. Brain perfusion SPECT in dementia syndromes

    International Nuclear Information System (INIS)

    Libus, P.; Stupalova, J.; Kuzelka, I.; Konrad, J.

    2002-01-01

    Aim: Brain perfusion SPECT is used in differential diagnostics of dementia syndromes. First of all the aim is to distinguish vascular dementia from degenerative dementia and to differentiate dementia from delirium, psychiatric syndromes, depression and secondary dementia, which is important in relation to therapy. The purpose of our study was to detect significance of BP SPECT and include it into the diagnostic process in dementia syndromes. Materials and methods: 51 women and 63 men aged 55 - 88 were evaluated in the study. The patients correspond to the general criteria of dementia diagnosis. They were sent to the examination by neurological, internal and psychiatric departments and out-patient departments. All patients were examined by 99mTc ECD SPECT using a double head camera PRISM 200 VP with LEHR collimator. The scintigraphic data were evaluated by the visual and semiquantitative analysis. Results: It was established that most patients in our group had vascular dementia, while Alzheimer's disease was second. In other groups we found out dementia at strategic infarct location, e.g. in gyrus angularis in the dominant hemisphere, frontal temporal lobe dementia and alcoholic dementia. Twenty-four patients had a normal diagnosis. Fifteen of them had a somatic reason of the delirious state and were re-classified into pseudodementia. Nine patients were not diagnostically included and the examination will repeated in four months time. Conclusion: We have found out a good applicability of brain perfusion SPECT in dementia syndromes diagnosis in our work. The best diagnosticable and most specific were the findings in multi-infarct dementia, Alzheimer's disease and frontal temporal lobe dementia. When vascular dementia is concerned we can even distinguish dementia at strategic infarction location, e.g. in thalamus, basal frontal telencefalon, in gyrus angularis of the dominant hemisphere, etc

  17. A Aderência dos Pronunciamentos Contábeis do CPC às Normas Internacionais de Contabilidade

    Directory of Open Access Journals (Sweden)

    Jorge Andrade Costa

    2012-09-01

    Full Text Available A convergência para os padrões contábeis internacionais tem se tornado um assunto relevante, com agenda definida para sua adesão em muitos países ao redor do mundo. No Brasil, coube ao CPC a responsabilidade de emitir pronunciamentos contábeis de acordo com as normas IFRS. Cada documento emitido pelo CPC corresponde a uma norma internacional de contabilidade emitida pelo IASB. Este trabalho tem como objetivo comparar os pronunciamentos do CPC com as normas do IASB e verificar a existência de diferenças entre os mesmos. Para tanto, realizou-se uma pesquisa documental aos pronunciamentos do CPC e às normas do IASB. Utilizou-se a técnica da análise de conteúdo, tendo o tema como unidade de significação. O universo de análise compreendeu os 65 pronunciamentos técnicos que estão sendo utilizados nas demonstrações contábeis das companhias brasileiras, emitidos pelo CPC entre os anos de 2007 a 2011. Os resultados apontaram para a existência de diferenças entre os pronunciamentos emitidos pelo CPC e as normas emitidas pelo IASB, as quais foram agrupadas em quatro categorias de análise. Após análise, concluiu-se que as diferenças apontadas não prejudicam a declaração de que as demonstrações contábeis consolidadas brasileiras, preparadas de acordo com os CPCs estão de acordo com as normas do IASB. Palavras-chave: CPC, IFRS, IASB, demonstrações contábeis

  18. Prognostischer Wert der Fläche und Dichte von Lymphgefäßen bei kutanem Plattenepithelkarzinom.

    Science.gov (United States)

    Krediet, Jorien Tannette; Kanitakis, Jean; Bob, Adrienne; Schmitter, Julia; Carine Krediet, Annelot; Röwert, Joachim; Stockfleth, Eggert; Painsi, Clemens; Hügel, Rainer; Terhorst, Dorothea; Lange-Asschenfeldt, Bernhard

    2016-11-01

    Kutane Plattenepithelkarzinome (SCC) sind bekannt für ihre Fähigkeit, über Lymphgefäße zu metastasieren. In neueren Studien wird das Ausmaß der Lymphangiogenese als möglicher prognostischer Faktor bei einigen Hauttumoren genannt. Ziel dieser Studie war die Quantifizierung der Lymphangiogenese bei SCC entweder durch computergestützte Bildanalyse oder mithilfe der Zählmethode nach Chalkley. Gefäßparameter wurden im Hinblick auf ihre Vorhersagekraft für die Bildung von Tumormetastasen beurteilt und verglichen. In dieser Fallkontrollstudie wurden die klinischen und histologischen Daten von jeweils 15 SCC-Patienten mit bzw. ohne Metastasen retrospektiv analysiert. In den SCC-Proben wurde der für das Lymphendothel spezifische Marker D2-40 und der pan-vaskuläre Marker CD31 immunhistochemisch angefärbt und durch computergestützte morphometrische Bildanalyse in Hotspots sowie mithilfe der digitalisierten Zählmethode nach Chalkley analysiert. Die Dichte von Lymphgefäßen, die relative Lymphgefäßfläche und die mit der Chalkley-Methode ermittelte Zahl an Lymphgefäßen (Chalkley-Count) waren bei metastasierten SCC signifikant erhöht. Die Tumordicke war bei metastasierten SCC signifikant höher und besaß die höchste Vorhersagekraft für eine Metastasierung. Die Tumordicke war ein signifikanter Prädiktor für Lymphangiogeneseparameter. Die Lymphangiogenese ist bei metastasierten SCC erhöht, doch ihr Ausmaß wird von der Tumordicke beeinflusst. Die Tumordicke bildet weiterhin den zuverlässigsten prädiktiven Faktor für die Metastasierung. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  19. CT Perfusion of the Liver: Principles and Applications in Oncology

    Science.gov (United States)

    Kim, Se Hyung; Kamaya, Aya

    2014-01-01

    With the introduction of molecularly targeted chemotherapeutics, there is an increasing need for defining new response criteria for therapeutic success because use of morphologic imaging alone may not fully assess tumor response. Computed tomographic (CT) perfusion imaging of the liver provides functional information about the microcirculation of normal parenchyma and focal liver lesions and is a promising technique for assessing the efficacy of various anticancer treatments. CT perfusion also shows promising results for diagnosing primary or metastatic tumors, for predicting early response to anticancer treatments, and for monitoring tumor recurrence after therapy. Many of the limitations of early CT perfusion studies performed in the liver, such as limited coverage, motion artifacts, and high radiation dose of CT, are being addressed by recent technical advances. These include a wide area detector with or without volumetric spiral or shuttle modes, motion correction algorithms, and new CT reconstruction technologies such as iterative algorithms. Although several issues related to perfusion imaging—such as paucity of large multicenter trials, limited accessibility of perfusion software, and lack of standardization in methods—remain unsolved, CT perfusion has now reached technical maturity, allowing for its use in assessing tumor vascularity in larger-scale prospective clinical trials. In this review, basic principles, current acquisition protocols, and pharmacokinetic models used for CT perfusion imaging of the liver are described. Various oncologic applications of CT perfusion of the liver are discussed and current challenges, as well as possible solutions, for CT perfusion are presented. © RSNA, 2014 Online supplemental material is available for this article. PMID:25058132

  20. Development of an Ex Vivo, Beating Heart Model for CT Myocardial Perfusion

    NARCIS (Netherlands)

    Pelgrim, Gert Jan; Das, Marco; Haberland, Ulrike; Slump, Cees; Handayani, Astri; van Tuijl, Sjoerd; Stijnen, Marco; Klotz, Ernst; Oudkerk, Matthijs; Wildberger, Joachim E.; Vliegenthart, Rozemarijn

    2015-01-01

    Objective. To test the feasibility of a CT-compatible, ex vivo, perfused porcine heart model for myocardial perfusion CT imaging. Methods. One porcine heart was perfused according to Langendorff. Dynamic perfusion scanning was performed with a second-generation dual source CT scanner. Circulatory

  1. A FORMAÇÃO COMPORTAMENTAL DE AUDITORES CONTÁBEIS INDEPENDENTES: UM ESTUDO MULTICASO

    Directory of Open Access Journals (Sweden)

    Luiz Alberton

    2002-11-01

    Full Text Available RESUMO
    O presente artigo tem como objetivo apresentar uma proposta de um modelo de formação comportamental para auditores contábeis independentes. Deste modo, inicialmente, discorre-se sobre os aspectos que devem ser considerados pelo profissional responsável pela gestão das pessoas nas organizações que prestam serviços de auditoria contábil independente, e do perfil destas pessoas requerido pelas empresas. Em seguida são identificadas as teorias que tratam da gestão de pessoas nas organizações, especificamente nos processos de recrutamento e seleção, capacitação e avaliação de desempenho. As empresas buscam profissionais com talentos e, principalmente, que saibam manter o equilíbrio entre a razão e a emoção no ambiente de trabalho. Na literatura que versa sobre a profissão do auditor contábil, é dada muita ênfase aos aspectos técnicos, tratando superficialmente ou renegando os aspectos comportamentais considerados importantes ao desempenho destes profissionais. Para confirmar essas afirmações e dar suporte ao delineamento do modelo, é realizada uma pesquisa de campo com os responsáveis pela gestão de pessoas em quatro empresas internacionais de auditoria contábil independente, que fazem parte das big five, e em uma empresa nacional. Assim, para o delineamento do modelo de formação, a ênfase desta pesquisa recai sobre os aspectos de liderança, comunicação, motivação, negociação, coaching, mentoring, administração de conflitos, trabalho em equipe, técnica de entrevista, análise transacional e de programação neurolingüística, que podem ser utilizados para o desenvolvimento de auditores contábeis independentes, de forma que possam melhorar suas condições de competitividade e empregabilidade. Portanto, são incorporados esses conceitos como ponto de partida para o delineamento de um modelo de formação comportamental

  2. Imaging diagnostics of breast metastases from extramammary tumors; Bildgebende Diagnostik bei Brustmetastasen extramammaerer Tumoren

    Energy Technology Data Exchange (ETDEWEB)

    Wienbeck, S.; Lotz, J. [Georg-August-Universitaet Goettingen, Institut fuer Diagnostische und Interventionelle Radiologie, Goettingen (Germany); Nemat, S. [Universitaet Homburg/Saar, Institut fuer Diagnostische und Interventionelle Radiologie, Homburg/Saar (Germany); Surov, A. [Universitaet Leipzig, Institut fuer Diagnostische und Interventionelle Radiologie, Leipzig (Germany)

    2017-06-15

    klinischen Merkmale und die unterschiedlichen Bildgebungsbefunde intramammaerer Metastasen solider extramammaerer Tumoren aufgezeigt. Brustmetastasen werden haeufig zufaellig in Zusammenhang mit einer Computertomographie (CT) oder Positronenemissionstomographie-Computertomographie (PET-CT) entdeckt. Mammographisch weisen Brustmetastasen 2 unterschiedliche bildgebende Erscheinungsmuster im Sinne von Herdbefunden oder aber einer Architekturstoerung mit Kutisverdickung auf. Diese kommen in der Regel als solitaere, seltener als multiple runde Herdbefunde mit glatter Randbegrenzung zur Darstellung. Assoziierter Mikrokalk tritt selten auf. Eine diffuse Architekturstoerung mit Kutisverdickung kommt gehaeuft bei Brustmetastasen der meisten Magenkarzinome, Ovarialkarzinome und Rhabdomyosarkome vor. Sonographisch stellen sich die Befunde hypoechogen, oval oder rund mit glatter Randbegrenzung und dorsaler Schallverstaerkung dar. Die MR-Kriterien bei Brustmetastasen sind dagegen inkonstant und koennen nicht sicher als benigne oder maligne klassifiziert werden. Die erhobenen radiologischen Befunde imponieren hierbei eher benigne, sodass bei bekannter Malignomerkrankung stets an das Vorliegen von Brustmetastasen gedacht werden sollte. (orig.)

  3. 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

  4. Acute tolerance of hyperfractionated accelerated total body irradiation; Akuttoleranz bei der hyperfraktionierten akzelerierten Ganzkoerperbestrahlung

    Energy Technology Data Exchange (ETDEWEB)

    Latz, D. [Radiologische Universitaetsklinik Heidelberg (Germany). Abt. Klinische Radiologie; Schraube, P. [Radiologische Universitaetsklinik Heidelberg (Germany). Abt. Klinische Radiologie; Wannenmacher, M. [Radiologische Universitaetsklinik Heidelberg (Germany). Abt. Klinische Radiologie

    1996-12-01

    Background: Acute side effects of total body irradiation lead to intense molestations of the patients. Therefore, it is desirable to take measures to reduce these side effects. In a retrospective study the frequency on acute side effects of a hyperfractionated accelerated total body irradiation was assessed and compared to frequencies of other exposure schedules published in the literature. Additionally the influence of ondansetron on the frequency of nausea and vormiting was investigated. Patients and Method: From 1989 to 1992, 76 patients (47 male, 29 female; median age 38 years) underwent total body irradiation before autologeous bone marrow transplantation. They received 3 daily doses of 1.20 Gy each every 4 h on 4 successive days to a total dose of 14,40 Gy. Thirty-nine patients received 3x8 mg (daily, intravenous or per os) ondansetron during the whole course of irradiation. Results: The most relevant side effects were nausea and vomiting. Patients, who did not receive ondansetron (n=37) showed a nausea and emesis rate of 73%. With ondansetron (n=39) nausea and emesis were reduced to 38%. Also the grade of severity of these side effects was reduced. Conclusions: Ondansetron proved to be an effective medicament for relieving nausea and vormiting during total body irradiation. The results obtained are in concordance with those published in the literature. (orig.) [Deutsch] Hintergrund: Die Akutnebenwirkungen der Ganzkoerperbestrahlung fuehren zu starken Belastungen der Patienten. Massnahmen zur Reduktion dieser Nebenwirkungen sind daher notwendig. In einer retrospektiven Analyse wurde die Haeufigkeit von Akutnebenwirkungen bei einer hyperfraktionierten akzelerierten Granzkoerperbestrahlung untersucht und mit den Auftretenshaeufigkeiten anderer in der Literatur aufgefuehrter Fraktionierungsschemata verglichen. Zusaetzlich wurde der Einfluss des Serotoninantagonisten Ondansetron auf die Haeufigkeit von Uebelkeit und Erbrechen untersucht. Patienten und Methode

  5. Imaging of ventilation/perfusion ratio by gated regional spirometry

    International Nuclear Information System (INIS)

    Touya, J.J.; Jones, J.P.; Price, R.R.; Patton, J.A.; Erickson, J.J.; Rollo, F.D.

    1981-01-01

    Gated 133 Xe images of patients rebreathing into a closed system can provide images of the distribution of lung volumes, ventilation and specific ventilation. These have been shown to be accurate, precise, and do not require unusually sophisticated equipment or skills. A mathematical transformation is used to correct the images for lung movement, which does not alter the total number of counts in the image. Perfusion images are gated to remove motion blurring but not transformed. Ventilation/perfusion images showing the distribution of V/Q ratio are then generated from the individual ventilation and perfusion images. (author)

  6. Lung perfusion and ventilation scintigraphy in pre- and postoperative diagnostics

    International Nuclear Information System (INIS)

    Sandrock, D.; Munz, D.L.

    1998-01-01

    Lung perfusion (Tc-99m labeled albumin particles) and ventilation (Xe-133 gas) are used prior to thoracic surgery in order to evaluate changes in perfusion and ventilation due to the underlying diseases. Furthermore, perfusion scintigraphy allows combined with spirometry the prediction of the postinterventional vital capacity and the forced expiratory volume in 1 s. The correlation coefficient for this procedure compared with values measured postoperatively are in the range of 0.8. The method allows the assessment of operability in terms of postinterventional function. (orig.) [de

  7. Pathologic evaluation of normal and perfused term placental tissue

    DEFF Research Database (Denmark)

    Maroun, Lisa Leth; Mathiesen, Line; Hedegaard, Morten

    2014-01-01

    with addition of antibiotics to the medium. In the "normal" tissue, certain lesions were very frequent and showed only fair or poor interobserver agreement. Revised minimum criteria for these lesions were defined and found reproducible. This study has emphasized the value of pathologic examination...... and selected findings were tested against success parameters from the perfusions. Finally, the criteria for frequent lesions with fair to poor interobserver variation in the nonperfused tissue were revised and reanalyzed. In the perfused tissue, the perfusion artefact "trophoblastic vacuolization," which...

  8. Prevalence of ECG changes during adenosine stress and its association with perfusion defect on myocardial perfusion scintigraphy.

    Science.gov (United States)

    Taywade, Sameer K; Ramaiah, Vijayaraghavan L; Basavaraja, Harish; Venkatasubramaniam, Parameswaran R; Selvakumar, Job

    2017-04-01

    Myocardial perfusion scintigraphy (MPS) is a valuable, noninvasive imaging modality in the evaluation of patients with coronary artery disease. Adenosine stress may occasionally be associated with ECG changes. This study evaluated the strength of association between adenosine stress-related ECG changes and perfusion defects on Tc-MPS. 117 (mean age: 61.25±9.27 years; sex: men 87, women 30) patients with known/suspected coronary artery disease underwent adenosine stress MPS. ECG was monitored continuously during adenosine stress for ST-depression. On the basis of the summed difference score, reversible perfusion defects were categorized as follows: normal: less than 4, mild: 4-8, moderate: 9-13, and severe: more than 13. ST-depression was observed in 27/117 (23.1%) and reversible perfusion defects were observed in 18/27 (66.66%) patients. 2/27, 6/27, and 10/27 patients had mild, moderate, and severe ischemia, respectively. 9/27 patients had normal perfusion. ECG changes and perfusion defects showed a moderate strength of association (correlation coefficient r=0.35, P=0.006). The sensitivity, specificity, positive predictive value, and negative predictive value of ECG findings for prediction of ischemia were 35.29, 86.36, 67.67, and 63.33%, respectively. ECG changes during adenosine stress are not uncommon. It shows a moderate strength of association with reversible perfusion defects. ECG changes during adenosine merit critical evaluation of MPS findings.

  9. EFFECT ON PERFUSION VALUES OF SAMPLING INTERVAL OF CT PERFUSION ACQUISITIONS IN NEUROENDOCRINE LIVER METASTASES AND NORMAL LIVER

    Science.gov (United States)

    Ng, Chaan S.; Hobbs, Brian P.; Wei, Wei; Anderson, Ella F.; Herron, Delise H.; Yao, James C.; Chandler, Adam G.

    2014-01-01

    Objective To assess the effects of sampling interval (SI) of CT perfusion acquisitions on CT perfusion values in normal liver and liver metastases from neuroendocrine tumors. Methods CT perfusion in 16 patients with neuroendocrine liver metastases were analyzed by distributed parameter modeling to yield tissue blood flow, blood volume, mean transit time, permeability, and hepatic arterial fraction, for tumor and normal liver. CT perfusion values for the reference sampling interval of 0.5s (SI0.5) were compared with those of SI datasets of 1s, 2s, 3s and 4s, using mixed-effects model analyses. Results Increases in SI beyond 1s were associated with significant and increasing departures of CT perfusion parameters from reference values at SI0.5 (p≤0.0009). CT perfusion values deviated from reference with increasing uncertainty with increasing SIs. Findings for normal liver were concordant. Conclusion Increasing SIs beyond 1s yield significantly different CT perfusion parameter values compared to reference values at SI0.5. PMID:25626401

  10. Tc-99m DTPA perfusion scintigraphy and color coded duplex sonography in the evaluation of minimal renal allograft perfusion

    International Nuclear Information System (INIS)

    Bair, H.J.; Platsch, G.; Wolf, F.; Guenter, E.; Becker, D.; Rupprecht, H.; Neumayer, H.H.

    1997-01-01

    Aim: The clinical impact of perfusion scintigraphy versus color coded Duplex sonography was evaluated, with respect to their potential in assessing minimal allograft perfusion in vitally threatened kidney transplants, i.e. oligoanuric allografts suspected to have either severe rejection or thrombosis of the renal vein or artery. Methods: From July 1990 to August 1994 the grafts of 15 out of a total of 315 patients were vitally threatened. Technetium-99m DTPA scintigraphy and color coded Duplex sonography were performed in all patients. For scintigraphic evaluation of transplant perfusion analog scans up to 60 min postinjection, and time-activity curves over the first 60 sec after injection of 370-440 MBq Tc-99m diethylenetriaminepentaacetate acid (DTPA) were used and classified by a perfusion score, the time between renal and iliac artery peaks (TDiff) and the washout of the renogram curve. Additionally, evaluation of excretion function and assessment of vascular or urinary leaks were performed. By color coded Duplex sonography the perfusion in all sections of the graft as well as the vascular anastomoses were examined and the maximal blood flow velocity (Vmax) and the resistive index (RI) in the renal artery were determined by means of the pulsed Doppler device. Pathologic-anatomical diagnosis was achieved by either biopsy or post-explant histology in all grafts. Results: Scintigraphy and color coded Duplex sonography could reliably differentiate minimal (8/15) and not perfused (7/15) renal allografts. The results were confirmed either by angiography in digital subtraction technique (DSA) or the clinical follow up. Conclusion: In summary, perfusion scintigraphy and color coded Duplex sonography are comparable modalities to assess kidney graft perfusion. In clinical practice scintigraphy and colorcoded Doppler sonography can replace digital subtraction angiography in the evaluation of minimal allograft perfusion. (orig.) [de

  11. In-vivo quantitative evaluation of perfusion zones and perfusion gradient in the deep inferior epigastric artery perforator flap

    Science.gov (United States)

    Saint-Cyr, Michel; Lakhiani, Chrisovalantis; Cheng, Angela; Mangum, Michael; Liang, Jinyang; Teotia, Sumeet; Livingston, Edward H.; Zuzak, Karel J.

    2013-03-01

    The selection of well-vascularized tissue during DIEP flap harvest remains controversial. While several studies have elucidated cross-midline perfusion, further characterization of perfusion to the ipsilateral hemiabdomen is necessary for minimizing rates of fat necrosis or partial fat necrosis in bilateral DIEP flaps. Eighteen patients (29 flaps) underwent DIEP flap harvest using a prospectively designed protocol. Perforators were marked and imaged with a novel system for quantitatively measuring tissue oxygenation, the Digital Light Hyperspectral Imager. Images were then analyzed to determine if perforator selection influenced ipsilateral flap perfusion. Flaps based on a single lateral row perforator (SLRP) were found to have a higher level of hemoglobin oxygenation in Zone I (mean %HbO2 = 76.1) compared to single medial row perforator (SMRP) flaps (%HbO2 = 71.6). Perfusion of Zone III relative to Zone I was similar between SLRP and SMRP flaps (97.4% vs. 97.9%, respectively). These differences were not statistically significant (p>0.05). Perfusion to the lateral edge of the flap was slightly greater for SLRP flaps compared SMRP flaps (92.1% vs. 89.5%, respectively). SMRP flaps had superior perfusion travelling inferiorly compared to SLRP flaps (88.8% vs. 83.9%, respectively). Overall, it was observed that flaps were better perfused in the lateral direction than inferiorly. Significant differences in perfusion gradients directed inferiorly or laterally were observed, and perforator selection influenced perfusion in the most distal or inferior aspects of the flap. This suggests broader clinical implications for flap design that merit further investigation.

  12. Einsatz von E-Portfolios bei der Qualifizierung pädagogischer Professionals in restriktiven Settings

    Directory of Open Access Journals (Sweden)

    Dirk Jahn

    2010-05-01

    Full Text Available Der Beitrag zeigt den Einsatz von E-Portfolios bei der Qualifizierung pädagogischer Professionals in der beruflichen Bildung auf. Dabei werden als Referenz die Theorie der Selbstreflexion, des kritischen Denkens sowie des Konzeptwandels zugrunde gelegt. Es werden Möglichkeiten aufgezeigt, wie E-Portfolios auch in restriktiven Settings eingesetzt werden können. Bislang dominiert in der Literatur der Einsatz von E-Portfolios in der Schule bzw. in der Bildung von Lehrkräften. Restriktive Settings sind Settings, die für das formale Lernen nur kurze Zeiträume eröffnen, mit heterogenen Zielgruppen verbunden sind und die zum Teil ungünstige motivationale und kognitive Ausgangsvoraussetzungen mitbringen. Die dargestellten Ergebnisse fussen auf der Entwicklung, Erprobung und Erforschung eines solchen Settings, nämlich der Erprobung eines Qualifizierungskonzepts für pädagogische Professionals im Einzelhandel.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-12-31

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

  14. KETERKAITAN TEORI SIKLUS HIDUP KEUANGAN DALAM KEBIJAKAN DIVIDEN: STUDI PADA SEKTOR EKONOMI YANG LISTING DI BEI

    Directory of Open Access Journals (Sweden)

    Meuthia Hapsari Imayanti

    2015-09-01

    Full Text Available The purpose of this study is to analyze the linkage of financial life cycle theory to dividend policy. This study is using control variables consisting of Leverage, Return on Asset, Size and Asset Growth Rate. The data used in this study are the data in the sectors of primary and secondary market at Indonesia Capital Market (BEI. This study uses Binary Logistic Method. The factors that affect Dividend Policy in developed stock market seem to apply for this emerging market. Factor such as changes Size and ROA have positive effects on the probability of changes dividend. But, only Size has negative effects on the probability of omitting dividends. This research found that Financial Life Cycle difficult to seen in Indonesia, especially when the crisis is going onDOI: 10.15408/etk.v12i1.1902

  15. Catenary network concepts and autotransformer system at German Railway; Oberleitungsnetzkonzepte und Autotransformersystem bei der Deutschen Bahn

    Energy Technology Data Exchange (ETDEWEB)

    Eberling, W.; Levermann-Vollmer, D. [DB Energie GmbH, Frankfurt (Germany); Klinge, R.; Martens, G. [Balfour Beatty Rail GmbH, Power Systems, Offenbach (Germany)

    2002-07-01

    In Germany different circuitry designs have been developed for the catenaries supplied with AC 15 kV 16,7 Hz. By energy feeding with doubled voltage the multi-voltage system with autotransformers offers an advantageous alternative. Conversion of the about 130 km long double track line Prenzlau-Stralsund allows to suppress one converter station and three neutral sections as well as to save energy. Development of this pilot application will continue. (orig.) [German] Fuer die mit AC 15 kV 16,7 Hz gespeisten Oberleitungen in Deutschland wurden verschiedene Schaltungen entwickelt. Das Mehrspannungssystem mit Autotransformern bietet durch die Energiezufuhr mit doppelter Spannung eine guenstige Alternative. Bei der Umstellung der rund 130 km langen zweigleisigen Strecke Prenzlau-Stralsund kann auf ein Umformerwerk und drei Schutzstrecken verzichtet und Energie gespart werden. Diese Pilotanwendung wird weiter entwickelt. (orig.)

  16. Preface: BeiDou Navigation Satellite System (BDS)/GNSS+: Recent progress and new applications

    Science.gov (United States)

    Jin, Shuanggen

    2017-02-01

    Nowadays, the new China's BeiDou Navigation Satellite System (BDS) has been developed well. At the end of 2016, over 23 BDS satellites were launched, including five geostationary Earth orbit (GEO) satellites, five inclined geosynchronous orbit (IGSO) satellites and nine medium Earth orbit (MEO) satellites. The current BDS service covers China and most Asia-Pacific regions with accuracy of better than 10 m in positioning, 0.2 m/s in velocity and 50 ns in timing. The BDS with global coverage will be completely established by 2020 with five GEO satellites and 30 MEO satellites. The main function of BDS is the positioning, navigation and timing (PNT) as well as short message communications. Together with the United States' GPS, Russia's GLONASS and the European Union's Galileo system as well as other regional augmentation systems, more new applications of multi-Global Navigation Satellite Systems (GNSS) will be exploited and realized in the next decades.

  17. Anzeichen einer linearen dosis-effekt beziehung bei sehr kleinen bestrahlungsdosen

    CERN Document Server

    Diehl, I.

    1980-01-01

    Zur Aufstellung einer Strahlungsdosis - Effekt - Kurve bei kleinen Dosen wurde der Mikrokerntest verwendet, da er relativ einfach und gleich- zeitig sehr empfindlich ist. Die Bohne Vicia Faba (Fillbasket) wurde mit 60Co Gammastrahlen und mit hochenergetischen Neutronen bestrahlt. Die Neutronen wurden von 600 MeV Protonen, die auf ein Be—Target auftrafen produziert und unter einem Winkel von 0 Grad extrahiert. Informationen fiber Dosimetrie und Eigenschaften der verwandeten Strahlung wurder bereits an anderer Stelle beschriebenl) des gleichen auch Einzelheiten fiber die Aufzucht der BORE Vicia Fabaz). Nach der Bestrahlung wurden jeweils 5 Bohnen zu bestimmten Zeitpunkten fixiert und danach die Prfiparate herge— stellt. Pro Préparat wurden 1000 Zellen ausgewertet.

  18. Emission reduction in thermal processes for sewage sludge disposal; Emissionsreduzierung bei thermischen Verfahren zur Klaerschlammentsorgung

    Energy Technology Data Exchange (ETDEWEB)

    Nethe, L.P. [Maerker Umwelttechnik GmbH, Hamburg (Germany)

    1998-09-01

    Owing to the intensification of treatment processes and the construction of new sewage plants sewage arisings are due to rise considerably. The thermal treatment of sewage sludge which it has not been possible to avoid or utilise is an important and indispensable part of any sewage sludge disposal concept. If equipped with a state-of-the-art flue gas purification process that uses carbonaceous adsorbents (Sorbalit trademark), thermal treatment of sewage sludge can be regarded as an environmentally safe process technique. [Deutsch] Die anfallenden Klaerschlammengen werden durch die Intensivierung der Klaerprozesse und der Bau neuer Klaeranlagen deutlich zunehmen. Die thermische Behandlung nicht vermiedener oder verwerteter Klaerschlaemme stellt einen bedeutenden und unverzichtbaren Teil der Klaerschlamm-Entsorgungskonzepte dar. Bei Installation einer - dem Stand der Technik - entsprechenden Rauchgasreinigung mit dem Einsatz kohlenstoffhaltiger Adsorbentien (Sorbalit {sup trademark}) ist die thermische Behandlung von Klaerschlamm eine umweltsichere Verfahrenstechnik. (orig.)

  19. Analysis of conservativity analysis for clearance levels. Final report; Konservativitaetsanalysen bei Freigabegrenzwerten. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Deckert, A.; Thierfeldt, S.

    1997-07-01

    , raising the clearance levels would not lead to an increase of the material quantities because other nuclides of the respective nuclide vectors are limiting. In conclusion, the effort to alter the clearance levels of the 1995 SSK recommendation for conventional disposal does not seem worthwhile. (orig.) [Deutsch] Bei der Herleitung von Freigabewerten fuer Reststoffe/Abfaelle werden grundsaetzlich radiologisch notwendige Konservativitaeten einbezogen. Diese koennen fuer verschiedene Saetze von Freigabewerten allerdings stark differieren, was zu Inkompatibilitaeten zwischen Freigabepfaden fuehrt. Ziel ist daher der Vergleich der Konservativitaetsniveaus verschiedener Wertesaetze, wozu Konservativitaeten fuer Freigabewerte fuer Abfaelle zur Deponierung und fuer metallische Reststoffe analysiert werden. Es wurden Methoden erarbeitet, um den Grad an Konservativitaet quantitativ zu erfassen. Die Situation bei der Freigabe zur konventionellen Deponierung wurde analysiert, indem die aktuelle und zukuenftige Situation des Abfallaufkommens hinsichtlich Massen, Nuklidvektoren, geographischer Verteilung und Deponierung probabilistisch modelliert und die resultierende Dosisverteilung berechnet wurden. Als Freigabekriterium wurden die Grenzwerte fuer die Freigabe zur konventionellen Deponierung gemaess des SSK-Empfehlungsentwurfs von 1995 angesetzt. Auf der Basis realistischer Szenarien fuer die Exposition des Deponiepersonals und bei Zugrundelegung der Grenzwerte des SSK-Empfehlungsentwurfs wurde eine Dosisverteilung ermittelt, die zeigt, dass der Bereich des radiologischen Schutzziels im Bereich von 10 {mu}Sv/a nicht verlassen wird, auch wenn groessere Massen als 100 Mg/a freigegebenen Materials deponiert werden. Eine Beschraenkung der jaehrlich freigegebenen Masse oder Aktivitaet ist daher nicht erforderlich. Die Freigabewerte, die durch die Belastungspfade externe Bestrahlung und Inhalation bei Deponierpersonal bestimmt werden, weisen ein aehnliches Mass an Konservativitaet auf wie

  20. AS INFORMAÇÕES CONTÁBEIS E O AMBIENTE ECONÔMICO

    Directory of Open Access Journals (Sweden)

    Amaro Luiz de Oliveira Gomes

    2009-09-01

    Full Text Available As demonstrações financeiras, balanços patrimoniais, demonstrações do resultado, demonstrações de fluxo de caixa, acompanhadas das respectivas notas explicativas são a principal fonte de informações sobre as atividades econômicas relacionadas a uma determinada empresa. Tais fontes são utilizadas freqüentemente para avaliar o desempenho de uma instituição e de seus administradores, bem como para inferir sobre as perspectivas futuras do negocio. Embora sirva a uma variedade de usuários e para uma serie de utilidades, reconhece-se que as informações contábeis são basicamente utilizadas por aqueles que estão fora da empresa, tais como fornecedores, financiadores, os investidores, os quais estão preocupados principalmente com o destino dado pela gerencia da empresa aos recursos investidos.

  1. Magnetic resonance imaging for ankylosing spondylitis; Magnetresonanztomographie bei ankylosierender Spondylitis (Morbus Struempell-Marie-Bechterew)

    Energy Technology Data Exchange (ETDEWEB)

    Bollow, M. [Augusta-Kranken-Anstalt, Inst. fuer Radiologie, Bochum (Germany)

    2002-12-01

    ] Die ankylosierende Spondylitis (AS) gilt als Prototyp der Spondylarthropathien, welche mit einer Praevalenz von 2% zu den haeufigsten rheumatischen Erkrankungen gerechnet werden. Die Spondylarthropathie umfasst die 5 Entitaeten AS, reaktive Arthritis, Psoriasis arthropathica, enteropathische Arthritis bei Morbus Crohn und Colitis ulcerosa und die undifferenzierte Spondylarthropathie. Bei 99% der Patienten mit AS sind die ersten pathologischen Befunde an den Sakroiliakalgelenken zu finden. Die zur Diagnose einer AS geforderten Roentgenbefunde treten erst mit einer Latenz von 5-9 Jahren nach Beginn der klinischen Symptome in Erscheinung. Mit Hilfe der MRT der Sakroiliakalgelenke lassen sich sowohl chronisch-entzuendliche Veraenderungen (Erosionen, Sklerosierungen, Knochenbruecken) als auch akut-entzuendliche Veraenderungen (Synovitiden, Kapsulitiden, Osteitiden) sicher nachweisen und bezueglich ihrer Chronizitaet und Akuitaet graduieren. Enthesitiden der Ligamenta interossea des Spatium retroarticulare gehoeren zum Bild der AS. Eine Spondylodiszitis (Andersson 1937) kann als entzuendliche und als nichtentzuendliche Form (transdiskaler Ermuedungsbruch) auftreten. Zur Ankylosierung fuehrende Entzuendungen der Facetten- und der kostospinalen Gelenke sind fuer die AS typisch. Veraenderungen der Wirbelkoerper finden sich als Spondylitis anterior (Romanus 1952), posterior und marginalis. Charakteristisch fuer alle Spondylarthropathien sind darueberhinaus asymmetrische Synovitiden an den grossen Gelenken vor allem der unteren Extremitaet (Gonarthritis, Coxitis, Tarsitis, periphere Oligoarthritis), die Fibroostitis rheumatica (pelvine Enthesitis, Calcaneopathia rheumatica) und die Peri- und Synchondritiden der Symphysis pubica und der Synchondrosis sternalis. Da sich bei der AS fruehe entzuendliche Veraenderungen an der Wirbelsaeule und an den extravertebralen Manifestationsorten in der MRT vor deren Auftreten im Roentgenbild nachweisen lassen und damit die diagnostische Luecke

  2. MR spectroscopy in metabolic disorders of the brain; MR-Spektroskopie bei Stoffwechselerkrankungen des Gehirns

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-06-15

    Metabolic disorders of the brain often present a particular challenge for the neuroradiologist, since the disorders are rare, changes on conventional MR are often non-specific and there are numerous differential diagnoses for the white substance lesions. As a complementary method to conventional brain MRI, MR spectroscopy may help to reduce the scope of the differential diagnosis. Entities with specific MR spectroscopy patterns are Canavan disease, maple syrup urine disease, nonketotic hyperglycinemia and creatine deficiency. (orig.) [German] Die Diagnostik metabolischer Erkrankungen des Gehirns stellt eine besondere Herausforderung in der Neuroradiologie dar, da die Erkrankungen insgesamt selten, die bildmorphologischen Befunde haeufig unspezifisch sind und es eine Vielzahl von Differenzialdiagnosen fuer die Veraenderungen der weissen Substanz gibt. Als zusaetzliche Technik kann die MR-Spektroskopie bei Stoffwechselerkrankungen helfen, die Diagnose einzugrenzen. Krankheitsentitaeten, die spezifische Veraenderungen in der Spektroskopie aufweisen, sind der Morbus Canavan, die Ahornsirupkrankheit, die nichtketotische Hyperglyzinaemie und Kreatinmangelsyndrome. (orig.)

  3. ANALISIS RASIO ALTMAN MODIFIKASI PADA PREDIKSI KEBANGKRUTAN PERUSAHAAN PROPERTY DAN REAL ESTATE YANG TERDAFTAR DI BEI

    Directory of Open Access Journals (Sweden)

    Anita Tri Widiyawati

    2015-10-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui pengaruh rasio Altman Modifikasi terhadap prediksi kebangkrutan. Jenis penelitian ini termasuk penelitian kuantitatif. Populasi dalam penelitian ini adalah perusahaan property dan real estate yang terdaftar di BEI. Teknik pengambilan sampel menggunakan purposive sampling sehingga diperoleh sampel sejumlah 32 perusahaan property dan real estate yang menerbitkan laporan keuangannya selama tahun 2011-2013. Teknik analisis data menggunakan regresi logistik (logistic regression. Hasil penelitian menunjukkan bahwa: (1 working capital/total asset tidak berpengaruh terhadap prediksi kebangkrutan; (2 retained earning/total asset tidak berpengaruh terhadap prediksi kebangkrutan; (3 earning before interest and tax/total asset berpengaruh terhadap prediksi kebangkrutan; (4 market value of equity/book value of equity tidak berpengaruh terhadap prediksi kebangkrutan; (5 rasio Altman Modifikasi secara simultan berpengaruh terhadap prediksi kebangkrutan. Rasio Altman Modifikasi terbukti secara bersama-sama dapat digunakan untuk memprediksi kebangkrutan.

  4. Nitrogen emissions during pyrolysis and combustion; Einfluesse auf die Stickstofffreisetzung bei der Pyrolyse und Verbrennung

    Energy Technology Data Exchange (ETDEWEB)

    Koepsel, R.F.; Friebel, J.; Halang, S. [Technische Univ. Bergakademie Freiberg (Germany). Inst. IEC

    1998-09-01

    Reduction of nitric oxide emissions during brown coal combustion is an important contribution to clean utilisation of this very important domestic primary energy source. In modern processes, the nitrogen contained in the fuels is the main source of oxides. The distribution of this nitrogen in the products can be influenced by modifying the degassing parameters especially in the first phase of combustion, i.e. pyrolysis. The heat-up rate, pressure, as well as the genesis and mineral content of the coal were found to be the main influencing paramters. Depending on the fuel characteristics (degree of coalification, concentration of volatile matter, ash composition), the nitrogen released during pyrolysis and the nitrogen retained in the solid residue contribute to the total emissions of nitric oxides in different degrees. (orig.) [Deutsch] Die Verminderung der Stickoxidemission bei der Verbrennung von Braunkohle stellt einen wichtigen Beitrag zur sauberen Verwertung dieses bedeutendsten einheimischen Primaerenergietraegers dar. In modernen Prozessen bildet dabei der im Brennstoff gebundene Stickstoff die Hauptquelle der Oxide. Insbesondere durch Einflussnahme auf die Entgasungsbedingungen waehrend der ersten Phase der Verbrennung - der Pyrolyse - kann die Verteilung dieses Stickstoffes auf die Produkte beeinflusst werden. Als wesentliche Einflussgroessen auf die Einbindung in den verbleibenden Koks und die Freisetzung fluechtiger N-haltiger Gase (HCN, NH{sub 3}) wurden die Aufheizgeschwindigkeit, der Druck und die Mineralsubstanz der Kohle gefunden. Eine wesentliche Einflussgroesse stellt daneben auch die Herkunft der Kohlen dar. In Abhaengigkeit von den Brennstoffeigenschaften (Inkohlungsgrad, Gehalt an fluechtigen Bestandteilen, Aschezusammensetzung) tragen der waehrend der Pyrolyse freigesetzte und der im festen Rueckstand verbleibende Stickstoff in unterschiedlichem Masse zur Gesamtemission an Stickoxiden bei. (orig.)

  5. Dual vessel arterial spin labeling scheme for regional perfusion imaging.

    Science.gov (United States)

    Zimine, Ivan; Petersen, Esben Thade; Golay, Xavier

    2006-11-01

    Regional perfusion imaging (RPI) based on pulsed arterial spin labeling and angulated inversion slabs has been recently proposed. The technique allows mapping of individual brain perfusion territories of the major feeding arteries and could become a valuable clinical tool for evaluation of patients with cerebrovascular diseases. Here we propose a new labeling scheme for RPI where lateral and posterior circulations are labeled simultaneously. Two scans instead of three are sufficient to obtain the same perfusion territories as in the original approach, allowing for a 33% reduction in the total RPI protocol time. Moreover, the position of the inversion slabs with respect to vascular anatomy facilitates the planning and allows potentially better labeling efficiency. The new approach was tested on seven healthy volunteers and compared to the original labeling scheme. The results showed that the same perfusion territories and regional CBF values can be obtained. (c) 2006 Wiley-Liss, Inc.

  6. Carotid artery disease and low cerebral perfusion pressure

    DEFF Research Database (Denmark)

    Schroeder, T; Utzon, N P; Aabech, J

    1990-01-01

    pressures. Surgery in patients with low perfusion pressures seemed to be associated with an increased complication rate (12% versus 4%), although this was not statistically significant. Definite postoperative improvements in persisting neurological deficits were observed only in one patient. Long...

  7. Current perspectives in transplant medicine: hypothermic oxygenated perfusion

    Directory of Open Access Journals (Sweden)

    Michel SG

    2016-11-01

    Full Text Available Sebastian G Michel,1 Joren C Madsen2,3 1Department of Cardiac Surgery, Ludwig-Maximilians-University, Munich, Germany; 2Department of Surgery, Center for Transplantation Sciences, 3Division of Cardiac Surgery, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA Abstract: The purpose of this review was to provide an update on hypothermic oxygenated perfusion as a preservation technique for whole organ allografts. Clinical and experimental data in heart, lung, liver, kidney, and pancreas/islet transplantation are summarized with a special emphasis on marginal donors and donation after circulatory death. The rationale behind hypothermic machine perfusion as well as its advantages and disadvantages compared to conventional cold storage and the competing technique, normothermic machine perfusion, are reviewed. Keywords: organ transplantation, organ preservation, hypothermic perfusion

  8. Prematurity and brain perfusion: Arterial spin labeling MRI

    Directory of Open Access Journals (Sweden)

    Domenico Tortora

    2017-01-01

    Conclusions: ASL MRI demonstrated differences in brain perfusion of the basal ganglia between PN and TN. In PN, a positive correlation between CBF and neuromotor outcome was demonstrated in this area.

  9. Renal perfusion in chronic liver diseases: Evaluation by radiotechnetium renography

    International Nuclear Information System (INIS)

    Fanfani, G.; Fratello, A.; Mele, M.; Conte, E.; D'Addabbo, A.; Greco, L.

    1985-01-01

    Twenty-four patients with chronic liver diseases and seven normal controls were studied using renal and hepatic radiotechnetium angiography. The time-activity histograms generated were employed to calculate both the renal perfusion index (RPI) and the hepatic perfusion index (HPI). Renal perfusion proved to be reduced not only in cirrhotic patients but also in patients with aggressive chronic hepatitis, as well as in those with persistent chronic hepatitis. The HPI, which is to be considered as being strictly dependent on portal flow, only fell significantly in the group of cirrhotic patients. In all patient groups, the correlation coefficient between the HPI and RPI (mean of the two kidneys) was low (r=0.275) and not significant (P>0.05). After Warren's splenorenal derivation, renal perfusion did not improve but worsened, particularly in the left kidney where derivation anastomosis probably caused a venous overload. (orig.)

  10. Human males and females body thermoregulation: perfusion effect analysis.

    Science.gov (United States)

    Acharya, Saraswati; Gurung, D B; Saxena, V P

    2014-10-01

    Skin temperature is a common physiological parameter that reflects thermal responses. Blood perfusion is an important part of the physiological processes that the human body undergoes in order to maintain homeostasis. This study focuses on the effect of perfusion on the temperature distribution in human males and females body in different thermal environment. The study has been carried out for one dimensional steady cases using finite element method. The input parameter of the model is the blood perfusion or volumetric flow rate within the tissue. The appropriate physical and physiological parameters together with suitable boundary conditions that affect the heat regulations have been incorporated in the model. The study is to have a better understanding that how does thermoregulation change in human males and females skin layered due to perfusion. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Diagnostic value of transmural perfusion ratio derived from dynamic CT-based myocardial perfusion imaging for the detection of haemodynamically relevant coronary artery stenosis

    NARCIS (Netherlands)

    A. Coenen (Adriaan); M.M. Lubbers (Marisa); A. Kurata (Akira); A.K. Kono (Atsushi K.); A. Dedic (Admir); R.G. Chelu (Raluca Gabriela); M.L. Dijkshoorn (Marcel); A.G. Rossi (Adriano); R.J.M. van Geuns (Robert Jan); K. Nieman (Koen)

    2017-01-01

    textabstractObjectives: To investigate the additional value of transmural perfusion ratio (TPR) in dynamic CT myocardial perfusion imaging for detection of haemodynamically significant coronary artery disease compared with fractional flow reserve (FFR). Methods: Subjects with suspected or known

  12. A Review of Liver Perfusion Method in Toxicology Studies

    Directory of Open Access Journals (Sweden)

    M karami

    2014-06-01

    Full Text Available Introduction: The isolated perfused rat liver is an accepted method in toxicology studies. The isolated perfused rat liver (IPRL is a useful experimental system for evaluating hepatic function without the influence of other organ systems, undefined plasma constituents, and neural-hormonal effects. Methods: The untreated male rats (180-220gr body weight were anesthetised with ether and then surgery with proper method. The abdomen was opened through a midline and one transversal incision and the bile duct was cannulated. Heparin sodium solution (0.5 ml; 500 U/ml in 0.9% NaCl was injected via the abdominal vena cava to prevent blood clotting. The liver inferior venacava was cannulated with PE-10 tubing and secured. The portal vein was immediately cannulated with an 23gr catheter which was secured and then liver was perfused in situ by Krebs- Henseleit buffer (pH 7.4; saturated with 95% O2 and 5% CO2; 37°C at a flow rate of 20 ml/min for 3hr. Temperature, perfusion pressure, flow rate and perfusion fluid pH were closely monitored during the perfusion. Results: Transferase enzymes (ALT, AST alterations can be widely used as a measure of biochemical alterations in order to assess liver damage due to use of drugs such as isoniazid (INH and animal and plant toxins. Accumulated material in gallbladder are valuable samples to assess the level of Glutathione (GSH. Sections of perfused liver tissue can also be effectively analyzed for pathological aspects such as necrosis, fibrosis, cellularity. Conclusion: The isolated perfused rat liver (IPRL is a useful and Sutible experimental system for evaluating hepatic function. In this system, the effects of adjacent organs, on the liver is minimized

  13. CT perfusion image processing: analysis of liver tumors

    OpenAIRE

    D’Antò, Michela

    2013-01-01

    Perfusion CT imaging of the liver has potential to improve evaluation of tumour angiogenesis. Quantitative parameters can be obtained applying mathematical models to Time Attenuation Curve (TAC). However, there are still some difficulties for an accurate quantification of perfusion parameters due, for example, to algorithms employed, to mathematical model, to patient’s weight and cardiac output and to the acquisition system. In this thesis, new parameters and alternative methodologies ab...

  14. Whole brain CT perfusion on a 320-slice CT scanner

    Directory of Open Access Journals (Sweden)

    Jai Jai Shiva Shankar

    2011-01-01

    Full Text Available Computed tomography perfusion (CTP has been criticized for limited brain coverage. This may result in inadequate coverage of the lesion, inadequate arterial input function, or omission of the lesion within the target perfusion volume. The availability of 320-slice CT scanners offers whole brain coverage. This minimizes the chances of misregistration of lesions regardless of location, and makes the selection of the arterial input function easy. We present different clinical scenarios in which whole brain CTP is especially useful.

  15. Automatic extraction of left ventricle in SPECT myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Liu Li; Zhao Shujun; Yao Zhiming; Wang Daoyu

    1999-01-01

    An automatic method of extracting left ventricle from SPECT myocardial perfusion data was introduced. This method was based on the least square analysis of the positions of all short-axis slices pixels from the half sphere-cylinder myocardial model, and used a iterative reconstruction technique to automatically cut off the non-left ventricular tissue from the perfusion images. Thereby, this technique provided the bases for further quantitative analysis

  16. Separation of myoglobin and hemoglobin in isolated perfused pig heart

    Science.gov (United States)

    Rauh, Robert; Hiller, Michael; Trinks, Tobias; Kessler, Manfred D.

    2001-10-01

    For the quantitative determination of hemoglobin concentration in heart muscle it is important to distinguish between myoglobin and hemoglobin, two dyes with very similar optical absorption properties. With an isolated perfused pig heart model and EMPHO II SSK we measured tissue spectra in the visible range before and after adding erythrocytes to the perfusate. By calculating light intensity differences we were able to show spatial hemoglobin distribution in heart muscle.

  17. Bedeutung der Zink-Protoporphyrin-Bestimmung für die Steuerung der Eisensubstitution bei Hämodialysepatienten mit renaler Anämie

    OpenAIRE

    Kurp, G. (Gregor)

    2005-01-01

    In der Arbeit wurde bei 181 Dialysepat. der Einfluss parenteraler Eisentherapie Fe-Th auf die MCVretis, MCHretis, MCV, MCH sowie auf EPO-Dosis, bezogen auf die Eisenstoffwechselparameter ESWP: Zinkprotoporphyrin ZnPP, Ferritin Fr und Transferrinsätt. TS analysiert. Zwischen ESWP und MCV, MCH, MCVr, MCHr bestand eine sign. Korrelation. Der MCH-Anstieg nach Fe-Th war bei Pat. mit MCHr 28 p

  18. Funktionelle Bedeutung von VCAM-1 und CD4+ T-Zellen fuer die Induktion einer protektiven Immunantwort bei der murinen Toxoplasmose

    OpenAIRE

    Luetjen, Sonja

    2003-01-01

    In der vorliegenden Arbeit wurde die Funktion des Zelladhaesionsmolekuels VCAM-1 (Vascular Cell Adhesion Molecule-1) bei der Toxoplasmose, und damit erstmals bei einer murinen Infektionskrankheit, analysiert. Dazu wurden VCAMflox/flox MxCre Maeuse verwendet, in denen das VCAM-1-Gen durch eine IFN-alpha induzierbare Cre loxP-abhaengige Deletion neonatal ausgeschaltet war. Dies fuehrte zu einer fehlenden Induktion von VCAM-1 auf den...

  19. Botulinumtoxin-A in der Behandlung neurogener Blasenfunktionsstörungen bei Kindern: Funktionelle und histomorphologische Langzeitergebnisse

    Directory of Open Access Journals (Sweden)

    Schulte-Baukloh H

    2004-01-01

    Full Text Available Die etablierte Therapie der neurogenen Detrusorhyperaktivität bei Kindern besteht in der Gabe von Anticholinergika und begleitendem intermittierendem Einmalkatheterismus. Eine hohe Nebenwirkungsrate der Anticholinergika oder eine nicht ausreichende Dämpfung der Detrusoraktivität limitiert jedoch die Anwendung und zwingt nicht selten zu einem operativen Vorgehen. Wir untersuchten deshalb die Wirksamkeit von Botulinumtoxin-A (BTX-A auf die neurogene Detrusorhyperaktivität bei Kindern mit neurogener Blasenfunktionsstörung. Hierzu wurden 24 Kinder (11 Mädchen, 13 Jungen; 2,5–20 (Ø 11,9 Jahre mit maximalem Detrusordruck 40 cm H2O trotz anticholinerger Medikation in die Studie eingeschlossen. Nach urodynamischer Evaluierung wurden gewichtsadaptiert 85–300 U BTX-A (Botox(R zystoskopisch an 30–40 Stellen in den M. detrusor injiziert. Urodynamische Kontrollen erfolgten nach 1, 3 und 6 Monaten. Urodynamisch fand sich ein erhöhtes Reflexvolumen nach 1 Monat um +84 %, nach 3 Monaten um +68 % und nach 6 Monaten um +23 %. Entsprechend verhielten sich die Maximalkapazitäten: +35 % (nach 1 Monat, +23 % (nach 3 Monaten und +36 % (nach 6 Monaten. Die Maximaldrücke veränderten sich im o.g. Zeitraum um –41 %, –22 % bzw. +4 %. Die korrespondierenden Veränderungen der Inkontinenzrate betrug –46 %, –15 % bzw. –13 %. Bei 5 Kindern konnte jedoch auch mit dieser Therapie keine zufriedenstellende Drucksituation sichergestellt werden; nach der daraufhin durchgeführten Blasenaugmentation fanden sich in den Blasenresektaten histomorphologisch typische BTX-A bedingte Veränderungen, die jedoch in ihrer Ausprägung keinen signifikanten Gradienten aufwiesen. Zusammenfassend läßt sich festhalten, daß es nach Botulinumtoxin-A-Injektion in den Detrusormuskel bei der Mehrzahl der Patienten zu einer ausgeprägten und therapeutisch relevanten Verbesserung sämtlicher urodynamischer Parameter bei sehr guter Verträglichkeit des Medikamentes kommt

  20. Perfusion-weighted MR imaging in persistent hemiplegic migraine

    Energy Technology Data Exchange (ETDEWEB)

    Mourand, Isabelle; Menjot de Champfleur, Nicolas; Carra-Dalliere, Clarisse; Le Bars, Emmanuelle; Bonafe, Alain; Thouvenot, Eric [Hopital Gui de Chauliac, Service de Neuroradiologie, Montpellier (France); Roubertie, Agathe [Hopital Gui de Chauliac, Service de Neuropediatrie, Montpellier (France)

    2012-03-15

    Hemiplegic migraine is a rare type of migraine that has an aura characterized by the presence of motor weakness, which may occasionally last up to several days, and then resolve without sequela. Pathogenesis of migraine remains unclear and, recently, perfusion-weighted imaging (PWI) has provided a non-invasive method to study hemodynamic changes during acute attacks. Two female patients were admitted in our hospital suffering from prolonged hemiparesis. In both cases, they underwent MRI examination using a 1.5 T magnet including axial diffusion-weighted and perfusion sequences. From each perfusion MRI acquisition two regions of interest were delineated on each hemisphere and, the index of flow, cerebral blood volume, mean transit time, and time to peak were recorded and asymmetry indices from each perfusion parameter were calculated. Perfusion alterations were detected during the attacks. In one case, we observed, after 3 h of left hemiparesia, hypoperfusion of the right hemisphere. In the other case, who presented a familial hemiplegic migraine attack, on the third day of a persistent aura consisting of right hemiplegia and aphasia, PWI revealed hyperperfusion of the left hemisphere. Asymmetry indices for temporal parameters (mean transit time and time to peak) were the most sensitive. These findings resolved spontaneously after the attacks without any permanent sequel or signs of cerebral ischemia on follow-up MRI. PWI should be indicated for patients with migraine attacks accompanied by auras to assess the sequential changes in cerebral perfusion and to better understand its pathogenesis. (orig.)

  1. Role of myocardial perfusion SPECT in asymptomatic diabetic patients

    International Nuclear Information System (INIS)

    Cho, I.; Chun, K.; Won, K.; Lee, H.; Park, J.; Shin, D.; Kim, Y.; Shim, B.; Lee, J.

    2002-01-01

    Purpose: It is important that early diagnosis and treatment of coronary artery disease in diabetic patients, but there are few reports on the prevalence of stress-induced myocardial perfusion abnormalities and the rates of cardiac event in patients with type 2 diabetes. We evaluated the scan findings on gated myocardial perfusion SPECT in asymptomatic diabetic patients. Methods: We performed pharmacological stress test and gated perfusion SPECT in 69 diabetic patients without cardiovascular symptom (mean age: 65 year, male 31 and female 38). Patients underwent two-day imaging protocol and stress study was performed injection of Tc-99m MIBI during adenosine infusion. We followed up these patients by reviewing medical records. Results: Fifty-two of 69 patients (74.5%) showed normal scan findings and 17 patients (24.6%) showed reversible or fixed perfusion defects. Three of 52 patients with normal scan findings showed decreased LV ejection fraction and decreased wall motion. Twenty-three patients with normal scan findings were possible to follow up for more than 1yr (mean time: 18.3±3.3 mo.) and they all had no cardiac event. Three patients with reversible perfusion defects were performed coronary angioplasty. Conclusion: Myocardial perfusion SPECT is a noninvasive method and maybe useful in early diagnosis and predicting prognosis in diabetic patients

  2. CT Perfusion Characteristics Identify Metastatic Sites in Liver

    Directory of Open Access Journals (Sweden)

    Yuan Wang

    2015-01-01

    Full Text Available Tissue perfusion plays a critical role in oncology because growth and migration of cancerous cells require proliferation of new blood vessels through the process of tumor angiogenesis. Computed tomography (CT perfusion is an emerging functional imaging modality that measures tissue perfusion through dynamic CT scanning following intravenous administration of contrast medium. This noninvasive technique provides a quantitative basis for assessing tumor angiogenesis. CT perfusion has been utilized on a variety of organs including lung, prostate, liver, and brain, with promising results in cancer diagnosis, disease prognostication, prediction, and treatment monitoring. In this paper, we focus on assessing the extent to which CT perfusion characteristics can be used to discriminate liver metastases from neuroendocrine tumors from normal liver tissues. The neuroendocrine liver metastases were analyzed by distributed parameter modeling to yield tissue blood flow (BF, blood volume (BV, mean transit time (MTT, permeability (PS, and hepatic arterial fraction (HAF, for tumor and normal liver. The result reveals the potential of CT perfusion as a tool for constructing biomarkers from features of the hepatic vasculature for guiding cancer detection, prognostication, and treatment selection.

  3. CT Perfusion Characteristics Identify Metastatic Sites in Liver.

    Science.gov (United States)

    Wang, Yuan; Hobbs, Brian P; Ng, Chaan S

    2015-01-01

    Tissue perfusion plays a critical role in oncology because growth and migration of cancerous cells require proliferation of new blood vessels through the process of tumor angiogenesis. Computed tomography (CT) perfusion is an emerging functional imaging modality that measures tissue perfusion through dynamic CT scanning following intravenous administration of contrast medium. This noninvasive technique provides a quantitative basis for assessing tumor angiogenesis. CT perfusion has been utilized on a variety of organs including lung, prostate, liver, and brain, with promising results in cancer diagnosis, disease prognostication, prediction, and treatment monitoring. In this paper, we focus on assessing the extent to which CT perfusion characteristics can be used to discriminate liver metastases from neuroendocrine tumors from normal liver tissues. The neuroendocrine liver metastases were analyzed by distributed parameter modeling to yield tissue blood flow (BF), blood volume (BV), mean transit time (MTT), permeability (PS), and hepatic arterial fraction (HAF), for tumor and normal liver. The result reveals the potential of CT perfusion as a tool for constructing biomarkers from features of the hepatic vasculature for guiding cancer detection, prognostication, and treatment selection.

  4. Perfusion-weighted MR imaging in persistent hemiplegic migraine

    International Nuclear Information System (INIS)

    Mourand, Isabelle; Menjot de Champfleur, Nicolas; Carra-Dalliere, Clarisse; Le Bars, Emmanuelle; Bonafe, Alain; Thouvenot, Eric; Roubertie, Agathe

    2012-01-01

    Hemiplegic migraine is a rare type of migraine that has an aura characterized by the presence of motor weakness, which may occasionally last up to several days, and then resolve without sequela. Pathogenesis of migraine remains unclear and, recently, perfusion-weighted imaging (PWI) has provided a non-invasive method to study hemodynamic changes during acute attacks. Two female patients were admitted in our hospital suffering from prolonged hemiparesis. In both cases, they underwent MRI examination using a 1.5 T magnet including axial diffusion-weighted and perfusion sequences. From each perfusion MRI acquisition two regions of interest were delineated on each hemisphere and, the index of flow, cerebral blood volume, mean transit time, and time to peak were recorded and asymmetry indices from each perfusion parameter were calculated. Perfusion alterations were detected during the attacks. In one case, we observed, after 3 h of left hemiparesia, hypoperfusion of the right hemisphere. In the other case, who presented a familial hemiplegic migraine attack, on the third day of a persistent aura consisting of right hemiplegia and aphasia, PWI revealed hyperperfusion of the left hemisphere. Asymmetry indices for temporal parameters (mean transit time and time to peak) were the most sensitive. These findings resolved spontaneously after the attacks without any permanent sequel or signs of cerebral ischemia on follow-up MRI. PWI should be indicated for patients with migraine attacks accompanied by auras to assess the sequential changes in cerebral perfusion and to better understand its pathogenesis. (orig.)

  5. Impairment of myocardial perfusion in children with sickle cell disease

    International Nuclear Information System (INIS)

    Maunoury, C.; Acar, P.; Montalembert, M. de

    2003-01-01

    While brain, bone and spleen strokes are well documented in children with sickle cell disease (SCD), impairment of myocardial perfusion is an unknown complication. Non invasive techniques such as exercise testing and echocardiography have a low sensitivity to detect myocardial ischemia in patients with SCD. We have prospectively assessed myocardial perfusion with Tl-201 SPECT in 23 patients with SCD (10 female, 13 male, mean age 12 ± 5 years). Myocardial SPECT was performed after stress and 3 hours later after reinjection on a single head gamma camera equipped with a LEAP collimator (64 x 64 matrix size format, 30 projections over 180 deg C, 30 seconds per step). Left ventricular ejection fraction (LVEF) was assessed by equilibrium radionuclide angiography at rest on the same day. Myocardial perfusion was impaired in 14/23 patients: 9 reversible defects and 5 fixed defects. The left ventricular cavity was dilated in 14/23 patients. The mean LVEF was 63 ± 9%. There was no relationship between myocardial perfusion and left ventricular dilation or function. The frequent impairment of myocardial perfusion in children with SCD could lead to suggest a treatment with hydroxyurea, an improvement of perfusion can be noted with hydroxyurea. (author)

  6. Computed tomography angiography and perfusion to assess coronary artery stenosis causing perfusion defects by single photon emission computed tomography

    DEFF Research Database (Denmark)

    Rochitte, Carlos E; George, Richard T; Chen, Marcus Y

    2014-01-01

    AIMS: To evaluate the diagnostic power of integrating the results of computed tomography angiography (CTA) and CT myocardial perfusion (CTP) to identify coronary artery disease (CAD) defined as a flow limiting coronary artery stenosis causing a perfusion defect by single photon emission computed...... tomography (SPECT). METHODS AND RESULTS: We conducted a multicentre study to evaluate the accuracy of integrated CTA-CTP for the identification of patients with flow-limiting CAD defined by ≥50% stenosis by invasive coronary angiography (ICA) with a corresponding perfusion deficit on stress single photon...... myocardial infarction, the AUC was 0.90 (95% CI: 0.87-0.94) and in patients without prior CAD the AUC for combined CTA-CTP was 0.93 (95% CI: 0.89-0.97). For the combination of a CTA stenosis ≥50% stenosis and a CTP perfusion deficit, the sensitivity, specificity, positive predictive, and negative predicative...

  7. Xeno- and auto-perfusion of rabbit kidney. Machine perfusion with blood at 37 degrees C

    DEFF Research Database (Denmark)

    Jørgensen, K A; Kemp, E; Barfort, P

    1985-01-01

    damage, exudation, and IgG deposits along the basement membrane of the glomerular capillaries were the discriminative features of the xenoperfusion. In these experiments, we were unable to demonstrate any major role of platelets in the process leading to decreased blood flow.......Five rabbit kidneys were perfused with human blood and another five with their own blood in a re-circulating oxygenated system at 37 degrees C. The flow decreased to 2 ml/min. within 30 min. in all xenoperfusions, while none of the autoperfused had decreased to this level by 60 min. Endothelial...

  8. Assessment of the perfusion of glioblastomas before and during radiotherapy: longitudinal comparison between H2-15O positron emission tomography and perfusion MRI

    International Nuclear Information System (INIS)

    Laprie, A.; Ken, S.; Moyal Cohen-Jonathan, E.; Laprie, A.; Ken, S.; Lotterie, J.A.; Franceries, X.; Celsis, P.; Payoux, P.; Berry, I.; Lotterie, J.A.; Berry, I.; Barcelo, C.

    2010-01-01

    The authors report the comparison of different perfusion imagery modalities for patients suffering form glioblastomas and included in a phase-1 clinic trial comprising conformational radiotherapy concomitant with the use of a farnesyl-transferase inhibitor (tipifarnib). With these different techniques, perfusion MRI and perfusion positron emission tomography, the authors made respectively a qualitative and quantitative assessment of the tumour vascularisation. Short communication

  9. Myocardial perfusion assessment with contrast echocardiography

    Science.gov (United States)

    Desco, Manuel; Ledesma-Carbayo, Maria J.; Santos, Andres; Garcia-Fernandez, Miguel A.; Marcos-Alberca, Pedro; Malpica, Norberto; Antoranz, Jose C.; Garcia-Barreno, Pedro

    2001-05-01

    Assessment of intramyocardial perfusion by contrast echocardiography is a promising new technique that allows to obtain quantitative parameters for the assessment of ischemic disease. In this work, a new methodology and a software prototype developed for this task are presented. It has been validated with Coherent Contrast Imaging (CCI) images acquired with an Acuson Sequoia scanner. Contrast (Optison microbubbles) is injected continuously during the scan. 150 images are acquired using low mechanical index U/S pulses. A burst of high mechanical index pulses is used to destroy bubbles, thus allowing to detect the contrast wash-in. The stud is performed in two conditions: rest and pharmacologically induced stress. The software developed allows to visualized the study (cine) and to select several ROIs within the heart wall. The position of these ROIs along the cardiac cycle is automatically corrected on the basis of the gradient field, and they can also be manually corrected in case the automatic procedure fails. Time curves are analyzed according to a parametric model that incorporates both contrast inflow rate and cyclic variations. Preliminary clinical results on 80 patients have allowed us to identify normal and pathological patterns and to establish the correlation of quantitative parameters with the real diagnosis.

  10. Cerebral perfusion gammagraphy in neurology and neurosurgery

    International Nuclear Information System (INIS)

    Cardenas, Rene; Duran de Cardenas, Rosalia

    1998-01-01

    This paper describes six methods for measuring rCBF: 1) PET through 77 Kr, 15 O-water, 18 F-antipirine, 18 F-methane and 11 C-alcohols, 2) Wash measure of 133 Xe through SPECT or multidetectors, 3) CT contrasted through xenon, 4) planar gammagraphy or SPECT through 123 I-IMP or 123 I-HIPDM, 5) planar gammagraphy or radioisotopic tomography (SPECT) through 201 Tl-dietiltiocarbamate, and 6) planar gammagraphy or SPECT through 99m Tc lipofilics complex, 99m Tc-HMPAO and 99m Tc-ECD. They have been used for rCBF, , 133 Xe, 123 I-IMP 99m Tc-HMPAO studies, the two last ones are been used at the moment, the film performance is around 0.7 to 1.1 cm. The most useful radioisotopic techniques for gammagraphic study of cerebral perfusion have used HMPAO and 131 I-IMP labelled with 99m Tc

  11. CT perfusion of the liver during selective hepatic arteriography. Pure arterial blood perfusion of liver tumor and parenchyma

    International Nuclear Information System (INIS)

    Komemushi, Atsushi; Tanigawa, Noboru; Kojima, Hiroyuki; Kariya, Shuji; Sawada, Satoshi

    2003-01-01

    The purpose of this study was to quantify pure arterial blood perfusion of liver tumor and parenchyma by using CT perfusion during selective hepatic arteriography. A total of 44 patients underwent liver CT perfusion study by injection of contrast medium via the hepatic artery. CT-perfusion parameters including arterial blood flow, arterial blood volume, and arterial mean transit time in the liver parenchyma and liver tumor were calculated using the deconvolution method. The CT-perfusion parameters and vascularity of the tumor were compared. A complete analysis could be performed in 36 of the 44 patients. For liver tumor and liver parenchyma, respectively, arterial blood flow was 184.6±132.7 and 41.0±27.0 ml/min/100 g, arterial blood volume was 19.4±14.6 and 4.8±4.2 ml/100 g, and arterial mean transit time was 8.9±4.2 and 10.2±5.3 sec. Arterial blood flow and arterial blood volume correlated significantly with the vascularity of the tumor; however no correlation was detected between arterial mean transit time and the vascularity of the tumor. This technique could be used to quantify pure hepatic arterial blood perfusion. (author)

  12. Transplacental transfer of monomethyl phthalate and mono(2-ethylhexyl) phthalate in a human placenta perfusion system

    DEFF Research Database (Denmark)

    Mose, Tina; Knudsen, Lisbeth E; Hedegaard, Morten

    2007-01-01

    The transplacental passage of monomethylphtalate (mMP) and mono (2-ethylhexyl) phthalate (mEHP) was studied using an ex vivo placental perfusion model with simultaneous perfusion of fetal and maternal circulation in a single cotyledon. Umbilical cord blood and placental tissue collected both before...... and after perfusion were also analyzed. Placentas were obtained immediately after elective cesarean section and dually perfused in a recirculation system. mMP or mEHP was added to maternal perfusion medium to obtain concentrations at 10 and 25 microg/L, respectively. The placental transfer was followed...... analyzing samples from fetal and maternal perfusion media by liquid chromatography-mass spectrometry-mass spectrometry (LC-MS-MS). Four perfusions with mMP indicated a slow transplacental transfer, with a feto-maternal ratio (FM ratio) of 0.30 +/- 0.03 after 150 min of perfusion. Four perfusions with m...

  13. Reduktion der Invasivität bei nadelbasierter Bewegungskompensation für navigierte Eingriffe im Abdomen

    Science.gov (United States)

    Maier-Hein, L.; Tekbas, A.; Franz, A. M.; Tetzlaff, R.; Müller, S. A.; Pianka, F.; Wolf, I.; Kauczor, H.-U.; Schmied, B. M.; Meinzer, H.-P.

    Diese Arbeit stellt eine in-vivo Genauigkeitsstudie über das Kombinieren interner und externer Marker für die Bewegungskompensation bei Leberinterventionen vor. Abhängig von der Anzahl und Anordnung der verwendeten Marker sowie der angewandten Echtzeittransformation wurde bei kontinuierlicher Atmung eine Schätzgenauigkeit der Zielposition zwischen 1 und 5 mm erreicht. Das Hinzufügen einer einzigen Hilfsnadel zu einer Menge von Hautmarkern führte zu einer Fehlerreduktion von über 50%. Die Ergebnisse dieser Studie können in der Praxis verwendet werden, um basierend auf dem Tradeoff zwischen geringer Invasivität und hoher Genauigkeit eine geeignete Kombination von internen und externen Markern für eine gegebene Fragestellung zu wählen.

  14. Perfusion computed tomography to assist decision making for stroke thrombolysis.

    Science.gov (United States)

    Bivard, Andrew; Levi, Christopher; Krishnamurthy, Venkatesh; McElduff, Patrick; Miteff, Ferdi; Spratt, Neil J; Bateman, Grant; Donnan, Geoffrey; Davis, Stephen; Parsons, Mark

    2015-07-01

    The use of perfusion imaging to guide selection of patients for stroke thrombolysis remains controversial because of lack of supportive phase three clinical trial evidence. We aimed to measure the outcomes for patients treated with intravenous recombinant tissue plasminogen activator (rtPA) at a comprehensive stroke care facility where perfusion computed tomography was routinely used for thrombolysis eligibility decision assistance. Our overall hypothesis was that patients with 'target' mismatch on perfusion computed tomography would have improved outcomes with rtPA. This was a prospective cohort study of consecutive ischaemic stroke patients who fulfilled standard clinical/non-contrast computed tomography eligibility criteria for treatment with intravenous rtPA, but for whom perfusion computed tomography was used to guide the final treatment decision. The 'real-time' perfusion computed tomography assessments were qualitative; a large perfusion computed tomography ischaemic core, or lack of significant perfusion lesion-core mismatch were considered relative exclusion criteria for thrombolysis. Specific volumetric perfusion computed tomography criteria were not used for the treatment decision. The primary analysis compared 3-month modified Rankin Scale in treated versus untreated patients after 'off-line' (post-treatment) quantitative volumetric perfusion computed tomography eligibility assessment based on presence or absence of 'target' perfusion lesion-core mismatch (mismatch ratio >1.8 and volume >15 ml, core computed tomography-selected rtPA-treated patients to an Australian historical cohort of non-contrast computed tomography-selected rtPA-treated patients. Of 635 patients with acute ischaemic stroke eligible for rtPA by standard criteria, thrombolysis was given to 366 patients, with 269 excluded based on visual real-time perfusion computed tomography assessment. After off-line quantitative perfusion computed tomography classification: 253 treated patients and

  15. Analisis Pengaruh Informasi Laporan Arus Kas Terhadap Harga Saham Pada Perusahaan Perbankan Yang Terdaftar Di BEI Tahun 2009-2011

    OpenAIRE

    Azhari, Marwan

    2015-01-01

    This study aims to examine and analyze the influence of cashslow statement information to stock price partally and simultaneously in the banking company which listed in BEI. This study population is banking company listed on the Indonesia Stock Exchange in 2009 until 2011. Sample selection was done by using purposive sampling and obtained as many as 29 companies. The variables of this study consisted of operating cashflow, investing cashflow, and financing cashflow as independent variables...

  16. Anwendung des Traumatherapieverfahrens -Narrative Expositionstherapie- bei komplex traumatisierten Patienten unter besonderer Berücksichtigung des Schlafes

    OpenAIRE

    Scharff, Anna-Lena

    2016-01-01

    Die Studie sollte aufgrund der häufigen Komorbidität einer Posttraumatischen Belastungsstörung mit der Borderline Persönlichkeitsstörung die Frage untersuchen, ob die Narrative Expositionstherapie einen Therapieerfolg bei komplex traumatisierten Patienten hat. Desweiteren sollte der Effekt der Therapie auf den Schlaf untersucht werden und eventuell prädiktive Zusammenhänge zwischen Schlafqualität und Therapieerfolg herausgestellt werden.

  17. Kombinierte Hoch-/Niedrig-Dosis-Therapie mit systemischen Glukokor-tikoiden bei schweren Verlaufsformen der Alopecia areata im Kindesalter.

    Science.gov (United States)

    Jahn-Bassler, Karin; Bauer, Wolfgang Michael; Karlhofer, Franz; Vossen, Matthias G; Stingl, Georg

    2017-01-01

    Schwere Verlaufsformen der Alopecia areata (AA) im Kindesalter sind aufgrund limitierter Optionen therapeutisch herausfordernd. Systemische, hochdosierte Glukokortikoide weisen die schnellste Ansprechrate auf, nach dem Absetzen kommt es allerdings zu Rezidiven. Eine längerfristige Hochdosis-Anwendung ist aufgrund der zu erwartenden Nebenwirkungen nicht empfehlenswert. Eine dauerhafte Steroiderhaltungstherapie unterhalb der Cushing-Schwellen-Dosis nach Bolustherapie könnte die Krankheitsaktivität ohne Nebenwirkungen längerfristig unterdrücken. Im Rahmen einer offenen Anwendungsbeobachtung wurden 13 Kinder mit schweren Formen der AA in diese Studie eingeschlossen. Bei sieben Kindern lag eine AA totalis/universalis vor, bei sechs eine multifokale AA mit Befall von mehr als 50 % der Kopfhaut. Das Therapieregime sah eine initiale Prednisolon-Dosierung von 2 mg/kg Körpergeweicht (KG) vor und wurde innerhalb von neun Wochen auf eine Erhaltungsdosierung unter der individuellen Cushing-Schwelle reduziert. Der Nachbeobachtungszeitraum betrug ein bis drei Jahre. Wir beobachteten in 62 % aller Fälle ein komplettes Nachwachsen der Haare. Die mittlere Dauer bis zum Ansprechen lag bei 6,6 Wochen und konnte mit der Erhaltungstherapie über den gesamten Beobachtungszeitraum aufrechterhalten werden. An Nebenwirkungen wurden ausschließlich eine Gewichtszunahme (1-3 kg) bei allen Behandelten sowie eine milde Steroidakne in 23 % der Fälle beobachtet. Die kombinierte Hoch-/Niedrig-Dosis-Therapie mit systemischen Glukokortikoiden mittels Prednisolon zeigte eine hohe, dauerhafte Ansprechrate ohne signifikante Nebenwirkungen. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  18. Umgang mit Antithrombotika bei Operationen an der Haut vor und nach Publikation der entsprechenden S3-Leitlinie.

    Science.gov (United States)

    Gaskins, Matthew; Dittmann, Martin; Eisert, Lisa; Werner, Ricardo Niklas; Dressler, Corinna; Löser, Christoph; Nast, Alexander

    2018-03-01

    Laut einer Befragung im Jahre 2012 war der Umgang mit Antithrombotika bei dermatochirurgischen Eingriffen in Deutschland sehr heterogen. 2014 wurde erstmals eine evidenzbasierte Leitlinie zu diesem Thema veröffentlicht. Es wurde eine anonyme Befragung derselben Stichprobe zum Umgang mit Antithrombotika sowie zu Kenntnissen der Leitlinie durchgeführt. Die Ergebnisse wurden als relative Häufigkeiten berichtet und denen aus 2012 gegenübergestellt. 208 Antwortbögen wurden ausgewertet (Rücklaufquote: 36,6 %). Die große Mehrheit der Dermatologen erklärte, kleinere Eingriffe unter Fortführung der Therapie mit Phenprocoumon, niedrig dosierter Acetylsalicylsäure (≤ 100 mg) und Clopidogrel sowie mit direkten oralen Antikoagulanzien durchzuführen. Bei größeren Eingriffen war der Umgang hingegen weiterhin heterogen, insbesondere unter niedergelassenen Dermatologen. Der Anteil der Dermatologen, die Phenprocoumon, Acetylsalicylsäure und Clopidogrel leitlinienkonform verwendeten, hat sich insgesamt vergrößert. Führten 2012 beispielsweise 53,8 % der Klinikärzte bzw. 36,3 % der niedergelassenen Dermatologen eine große Exzision unter Fortführung der Therapie mit niedrig dosierter Acetylsalicylsäure durch, taten dies 2017 90,2 % bzw. 57,8 % (Phenprocoumon: 33,8 % bzw. 11,9 % auf 63,9 % bzw. 29,9 %; Clopidogrel: 36,9 % bzw. 23,2 % auf 63,9 % bzw. 30,6 %). Unter den Klinikärzten war ein hoher Anteil mit der Leitlinie vertraut und fand diese hilfreich. Eine Zunahme des leitlinienkonformen Verhaltens war bei allen Eingriffen zu verzeichnen. Bei größeren Eingriffen zeigte sich trotz deutlicher Verbesserung die Notwendigkeit verstärkter Anstrengungen zur Leitlinienumsetzung bzw. zur Identifizierung von Implementierungsbarrieren. © 2018 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  19. Berechnung von Gleichgewichtskonstanten mit Hilfe der Quantenchemie und Vergleich mit experimentellen Daten bei der Bildung von Halbacetalen

    OpenAIRE

    Jaubert, Silke

    2012-01-01

    Mischungen aus Aldehyden und Alkoholen sind für zahlreiche technische Prozesse von Bedeutung. Bei der Auslegung solcher Prozesse muss berücksichtigt werden, dass Aldehyde mit Alkoholen in einer Additions-Eliminierungsreaktion zu Halbacetalen reagieren. Zurzeit erhält man genaue Angaben zum Reaktionsgleichgewicht, die für technische Anwendungen ausreichend sind, fast ausschließlich aus experimentellen Untersuchungen. Eine Vorhersage solcher Gleichgewichtskonstanten (für Reaktionen in der Ga...

  20. Pengaruh Kualitas Auditor, Audit Delay Dan Audit Tenure Terhadap Kualitas Audit Perbankan Yang Terdaftar Di Bei Periode 2012-2014

    OpenAIRE

    Herianti, Eva; Suryani, Arna

    2016-01-01

    Informasi akuntansi dibutuhkan oleh berbagai pihak untuk proses pengambilan keputusan. Namun, informasi akuntansi yang dibuat oleh manajemen Perusahaan berpotensi dipengaruhi oleh kepentingan pribadi sehingga membutuhkan adanya pihak ketiga yang independen untuk memberikan penilaian atas kualitas informasi atas hasil audit. Penelitian ini bertujuan untuk menguji pengaruh kualitas auditor, audit delay dan audit tenure terhadap kualitas audit Perbankan yang terdaftar di BEI periode 2012-2014. M...

  1. Value of MR spectroscopy in infectious and inflammatory brain diseases; Wertigkeit der MR-Spektroskopie bei infektioesen und entzuendlichen Hirnerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Papanagiotou, P.; Schmidt, K.I.; Alexandrou, M.; Koerner, H.; Reith, W. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany)

    2010-09-15

    Proton magnetic resonance spectroscopy (MRS) is a non-invasive method for measuring cerebral metabolite concentrations in various pathologic conditions. This review discusses the MRS findings in the most common infectious and inflammatory brain diseases. (orig.) [German] Die Magnetresonanzspektroskopie (MRS) ist eine nichtinvasive Methode, die die Messung der Konzentration zerebraler Metaboliten erlaubt. Die Wertigkeit der MRS bei den wichtigsten infektioesen und entzuendlichen Hirnerkrankungen werden in diesem Review diskutiert. (orig.)

  2. FAKTOR-FAAKUTDOITR R YEAPNOGR MT ELMAGPE NGARUHI (Studi Empiris pada Perusahaan yang Terdaftar di BEI Tahun 2014-2016)

    OpenAIRE

    -, FAKTOR-FAAKUTDOITR R YEAPNOGR MT ELMAGPE NGARUHI (Studi Empiris pada Perusahaan yang Terdaftar di BEI Tahun 2014-2016)

    2017-01-01

    ABSTRAK Faktor-Faktor yang MempengaruhiAudit Report Lag (Studi Empiris pada Perusahaan yang Terdaftar di BEI Tahun 2014-2016) Factors that Affect Audit Report Lag (An Empirical Study on Companies Listed on Indonesia Stock Exchange in 2014-2016) RaStynaar aAfyinua D Saumlwaaynain ti M. Natsir Kadir jPeennise lpitiearnu sinaih baearntu jduaann kuenetufekk mtifeanng kuoji mpeiten gaaurudhit stoelrvhaabdialitpa sa, uudkiut rraenp opret rulasga hpaaadna, perusahaan yang ...

  3. [Intratympanic corticosteroid perfusion in the therapy of Meniere's disease].

    Science.gov (United States)

    Sanković-Babić, Snezana; Kosanović, Rade; Ivanković, Zoran; Babac, Snezana; Tatović, Milica

    2014-01-01

    Over the last two decades the intratympanic perfusion of corticosteroids has been used as a minimally invasive surgical therapy of Meniere's disease. According to experimental studies the antiinflammatory, immunoprotective, antioxidant and neuroprotective role of the locally perfused corticosteroids was noticed in the inner ear structures. The recovery of action potentials in the cells of the Corti organ was confirmed as well as a decreased expression of aquaporine-1, a glycoprotein responsible for labyrinth hydrops and N and K ions derangement. The study showed results of intratympanic perfusion therapy with dexamethasone in patients with retractable Meniere's disease who are resistant to conservative treatment. Single doses of 4 mg/ml dexamethasone were given intratympanically in 19 patients with retractable Meniere's disease. Six single successive doses of dexamethasone were administered in the posteroinferior quadrant of the tympanic membrane. Follow-up of the patients was conducted by using a clinical questionnaire a month after completed perfusion series as well as on every third month up to one year. One month after completed first course of perfusions, in 78% of patients, vertigo problems completely ceased or were markedly reduced. The recovery of hearing function was recorded in 68% and marked tinnitus reduction in 84% of patients. After a year of follow-up, in 63% of patients the reduction of vertigo persisted, while hearing function was satisfactory in 52%. Tinitus reduction was present in 73% of patients. Intratympanic perfusion of dexamethasone in patients with Meniere's disease is a minimally invasive therapeutic method that contributes to the reduction of the intensity of vertigo recurrent attacks, decrease of the intensity of tinnitus and improvement of the average hearing threshold. Patients with chronic diseases and Meniere's disease who are contraindicted for systemic administration of cortocosteroids (hypertension, diabetes, glaucoma, peptic

  4. Volume/perfusion ratio from lung SPECT/CT.

    Science.gov (United States)

    Schaefer, Wolfgang Michael; Knollmann, Daniela; Avondo, Jerome; Meyer, Andreas

    2018-02-01

    In pulmonary emphysema lung volume reduction procedures (LVRP) can optimize respiratory pump function. Identification of the most affected lobe can be reached using relative lobar volume (relVol) from CT, but this approach disregards the corresponding lobar perfusion. The aim of the study was therefore to establish a new parameter combining relVol from CT and relative perfusion (relPerf) from perfusion SPECT as a single parameter (volume/perfusion ratio (VPR)) to optimize the identification procedure. As a proof of principle VPR was calculated from hybrid V-/P-SPECT/CT scans from 20 patients with severe pulmonary emphysema (SPE) before LVRP. Lung V-/P-SPECT/CT (Siemens SymbiaT) was done with Technegas and 99mTc-MAA. Quantification of lobar perfusion from scintigraphy and volume from CT was performed using "HERMES Hybrid 3D - Lung Lobe Quantification". Using normal ranges - from 12 patients with suspected pulmonary embolism and normal lung structure and perfusion - all lobes were classified as normal or abnormal to identify targets for LVRP. Normal values for VPR: right upper lobe 1.09 ± 0.10, middle lobe 1.31 ± 0.31, right lower lobe 0.87 ± 0.08; left upper lobe 1.09 ± 0.11, left lower lobe 0.87 ± 0.12. In the 20 SPE patients there were only 7 lobes with pathological values for rel- Vol, 14 lobes with pathological values for rel- Perf but 31 lobes with pathological VPR. Estimation of VPR from lung SPECT/CT enables a combined view of lobar volume and perfusion with one parameter. In SPE patients VPR allows identifying possible target structures with much higher sensitivity than when using relPerf or relVol alone. The specificity and the prognostic value of this new parameter have to be tested in a clinical trial. Schattauer GmbH.

  5. Integrated screening concept in women with genetic predisposition for breast cancer; Integriertes Frueherkennungskonzept bei Frauen mit genetischer Praedisposition fuer Brustkrebs

    Energy Technology Data Exchange (ETDEWEB)

    Bick, U. [Muenster Univ. (Germany). Inst. fuer Klinische Radiologie

    1997-08-01

    Breast cancer is in 5% of cases due to a genetic disposition. BRCA1 and BRCA2 are by far the most common breast cancer susceptibility genes. For a woman with a genetic predisposition, the individual risk of developing breast cancer sometime in her life is between 70 and 90%. Compared to the spontaneous forms of breast cancer, woman with a genetic predisposition often develop breast cancer at a much younger age. This is why conventional screening programs on the basis of mammography alone cannot be applied without modification to this high-risk group. In this article, an integrated screening concept for women with genetic prodisposition for breast cancer using breast self-examination, clinical examination, ultrasound, mammography and magnetic resonance imaging is introduced. (orig.) [Deutsch] Mammakarzinome sind in etwa 5% auf eine genetische Disposition zurueckzufuehren. Am haeufigsten finden sich Mutationen im Bereich der Gene BRCA1 und BRCA2. Frauen mit einer genetischen Disposition erkranken in etwa 70-90% im Laufe ihres Lebens an einem Mammakarzinom. Das Erkrankungsalter bei diesen Frauen liegt in der Regel deutlich niedriger als bei den spontanen Formen des Mammakarzinoms, so dass vorhandene Frueherkennungskonzepte auf der Basis eines Mammographiescrennings nicht ohne weiteres auf dieses Hochrisikokollektiv uebertragbar sind. Im folgenden wird ein integriertes Konzept zur Frueherkennung bei Frauen mit genetischer Praedisposition fuer ein Mammakarzinom auf der Basis von Brustselbstuntersuchung, klinischer Untersuchung, Sonographie, Mammographie und Magnetresonanztomographie vorgestellt. (orig.)

  6. Guidelines on {sup 99m}Tc-DMSA scintigraphy in children; Empfehlungen zur Durchfuehrung der DMSA-Szintigraphie bei Kindern

    Energy Technology Data Exchange (ETDEWEB)

    Piepsz, A. [CHU St. Pierre, Bruessel (Belgium); Colarinha, P. [Instituto Portugues de Oncologia, Lissabon (Portugal); Gordon, I. [Great Ormend Street Hospital for Children, London (United Kingdom); Hahn, K. [Muenchen Univ. (Germany). Klinik fuer Nuklearmedizin; Olivier, P. [CHU Vandoeuvre, Nancy (France); Roca, I.; Velzen, J. van [Hospital Vall d' Hebron, Barcelona (Spain); Sixt, R. [The Queen Silvia Children' s Hospital, Goeteborg (Sweden)

    2000-11-01

    The guidelines are intended to help nuclear medical teams in their daily routine. The guidelines give information relating to indications, imaging parameters, data evaluation and interpretation. The guidelines are in line with the opinions of the Paediatric Committee of EANM and hence focus on approaches adopted in Europe, e.g. as regards selection of the radiopharmaceuticals or activity levels applied. The guidelines should be seen in the context of local quality standards and regulatory requirements. (orig./CB) [German] Zweck dieser Empfehlung ist es, dem Nuklearmedizinischen Team bei Tc-DMSA-Szintigraphie von Kindern Hilfestellung fuer die taegliche Routinepraxis zu geben. Die Empfehlung enthaelt Informationen ueber Indikationen, Aufnahmeparameter, Auswertung und Interpretation der DMSA-Szintigraphie bei Kindern. Die vorliegende Empfehlung fasst die Meinung des Paediatric Committee der EANM zusammen und ist daher mehr auf die Europaeische Vorgehensweise, z.B. bei der Wahl des Radiopharmazeutikums und den verwendeten Aktivitaetsmengen, ausgerichtet. Sie sollte immer in Zusammenhang mit lokalen Qualitaetsstandards und Vorschriften gesehen werden. (orig.)

  7. 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

  8. Ventilation-perfusion matching during exercise

    Science.gov (United States)

    Wagner, P. D.

    1992-01-01

    In normal subjects, exercise widens the alveolar-arterial PO2 difference (P[A-a]O2) despite a more uniform topographic distribution of ventilation-perfusion (VA/Q) ratios. While part of the increase in P(A-a)O2 (especially during heavy exercise) is due to diffusion limitation, a considerable amount is caused by an increase in VA/Q mismatch as detected by the multiple inert gas elimination technique. Why this occurs is unknown, but circumstantial evidence suggests it may be related to interstitial pulmonary edema rather than to factors dependent on ventilation, airway gas mixing, airway muscle tone, or pulmonary vascular tone. In patients with lung disease, the gas exchange consequences of exercise are variable. Thus, arterial PO2 may increase, remain the same, or fall. In general, patients with advanced chronic obstructive pulmonary disease (COPD) or interstitial fibrosis who exercise show a fall in PO2. This is usually not due to worsening VA/Q relationships but mostly to the well-known fall in mixed venous PO2, which itself results from a relatively smaller increase in cardiac output than VO2. However, in interstitial fibrosis (but not COPD), there is good evidence that a part of the fall in PO2 on exercise is caused by alveolar-capillary diffusion limitation of O2 transport; in COPD (but not interstitial fibrosis), a frequent additional contributing factor to the hypoxemia of exercise is an inadequate ventilatory response, such that minute ventilation does not rise as much as does CO2 production or O2 uptake, causing arterial PCO2 to increase and PO2 to fall.

  9. Adenosine stress protocols for myocardial perfusion imaging

    Directory of Open Access Journals (Sweden)

    Baškot Branislav

    2008-01-01

    Full Text Available Background/Aim. Treadmill test combined with myocardial perfusion scintigraphy (MPS is a commonly used technique in the assessment of coronary artery disease. There are many patients, however, who may not be able to undergo treadmill test. Such patients would benefit from pharmacological stress procedures combined with MPS. The most commonly used pharmacological agents for cardiac stress are coronary vasodilatators (adenosine, dipyridamol and catecholamines. Concomitant low-level treadmill exercise with adenosine pharmacologic stress (AdenoEX during MPS has become commonly used in recent years. A number of studies have demonstrated a beneficial impact of AdenoEX protocol. The aim of the study was, besides introducing into practice the two types of protocols of pharmatological stress test with adenosine, as a preparation for MPS, to compare and monitor the frequency of their side effects to quality, acquisition, as well as to standardize the onset time of acquisition (diagnostic imaging for both protocols. Methods. A total of 130 patients underwent pharmacological stress test with adenosine (vasodilatator. In 108 of the patients we performed concomitant exercise (AdenoEX of low level (50W by a bicycle ergometar. In 28 of the patients we performed Adenosine abbreviated protocol (AdenoSCAN. Side effects of adenosine were followed and compared between the two kinds of protocols AdenoEX and AdenoSCAN. Also compared were image quality and suggested time of acquisition after the stress test. Results. Numerous side effects were found, but being short-lived they did not require any active interventions. The benefit of AdenoEX versus AdenoSCAN included decreased side effects (62% vs 87%, improved safety and patients tolerance, improved target-to-background ratios because of less subdiaphragmatic activity, earlier acquisition, and improved sensitivity. Conclusion. The safety and efficacy of adenosine pharmacological stress is even better with concomitant

  10. Effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies.

    Science.gov (United States)

    Murase, Kenya; Nanjo, Takafumi; Ii, Satoshi; Miyazaki, Shohei; Hirata, Masaaki; Sugawara, Yoshifumi; Kudo, Masayuki; Sasaki, Kousuke; Mochizuki, Teruhito

    2005-11-07

    The purpose of this study was to investigate the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using multi-detector row CT (MDCT). Following the standard CT perfusion study protocol, continuous (cine) scans (1 s/rotation x 60 s) consisting of four 5 mm thick contiguous slices were performed using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. We generated the simulated images with tube currents of 50 mA, 100 mA and 150 mA by adding the corresponding noise to the raw scan data of the original image acquired above using a noise simulation tool. From the original and simulated images, we generated the functional images of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in seven patients with cerebrovascular disease, and compared the correlation coefficients (CCs) between the perfusion parameter values obtained from the original and simulated images. The coefficients of variation (CVs) in the white matter were also compared. The CC values deteriorated with decreasing tube current. There was a significant difference between 50 mA and 100 mA for all perfusion parameters. The CV values increased with decreasing tube current. There were significant differences between 50 mA and 100 mA and between 100 mA and 150 mA for CBF. For CBV and MTT, there was also a significant difference between 150 mA and 200 mA. This study will be useful for understanding the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using MDCT, and for selecting the tube current.

  11. Effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies

    International Nuclear Information System (INIS)

    Murase, Kenya; Nanjo, Takafumi; Ii, Satoshi; Miyazaki, Shohei; Hirata, Masaaki; Sugawara, Yoshifumi; Kudo, Masayuki; Sasaki, Kousuke; Mochizuki, Teruhito

    2005-01-01

    The purpose of this study was to investigate the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using multi-detector row CT (MDCT). Following the standard CT perfusion study protocol, continuous (cine) scans (1 s/rotation x 60 s) consisting of four 5 mm thick contiguous slices were performed using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. We generated the simulated images with tube currents of 50 mA, 100 mA and 150 mA by adding the corresponding noise to the raw scan data of the original image acquired above using a noise simulation tool. From the original and simulated images, we generated the functional images of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in seven patients with cerebrovascular disease, and compared the correlation coefficients (CCs) between the perfusion parameter values obtained from the original and simulated images. The coefficients of variation (CVs) in the white matter were also compared. The CC values deteriorated with decreasing tube current. There was a significant difference between 50 mA and 100 mA for all perfusion parameters. The CV values increased with decreasing tube current. There were significant differences between 50 mA and 100 mA and between 100 mA and 150 mA for CBF. For CBV and MTT, there was also a significant difference between 150 mA and 200 mA. This study will be useful for understanding the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using MDCT, and for selecting the tube current

  12. 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

  13. [Cardiodoron® bei Patienten mit Schlafstörungen - Ergebnisse einer prospektiven Beobachtungsstudie].

    Science.gov (United States)

    Rother, Claudia; Schnelle, Martin

    Hintergrund: Schlafstörungen gehören zu den häufigsten gesundheitlichen Problemen der heutigen Zeit. Stress und die dadurch bedingte innere Anspannung sowie eine unrhythmische Lebensführung z.B. durch Schichtarbeit sind bekannte auslösende Faktoren. Weniger bekannt ist, dass auch funktionelle Herz-Kreislauf-Beschwerden zu Störungen des Schlafs führen können und dass deren Behandlung zu einer Verbesserung der Schlafqualität beiträgt. Ganzheitlich betrachtet geht es daher um die Wiederherstellung einer gesunden Rhythmik, insbesondere des Herz-/Atem- sowie des Schlaf-Wach-Rhythmus, die Cardiodoron®, eine Heilpflanzenkomposition aus Primula veris, Hyoscyamus niger und Onopordum acanthium, unterstützt. Patienten und Methoden: Mittels einer prospektiven, multizentrischen Beobachtungsstudie sollte ermittelt werden, wie sich funktionelle Herz-Kreislauf-Beschwerden und/oder Schlafstörungen unter der Behandlung mit Cardiodoron® (Dilution) über 3-6 Monate entwickeln. Im Zeitraum von September 2009 bis März 2012 dokumentierten 92 Ärzte 501 Patienten, von denen 380 über Schlafstörungen klagten und deren Daten in dieser Publikation näher betrachtet werden. Nach einer Aufnahmeuntersuchung erfolgte nach 90 Tagen eine Abschlussuntersuchung und bei Fortführung der Therapie nach nochmals 90 Tagen eine Follow-up-Untersuchung. Neben 30 ärztlicherseits bewerteten Symptomen beurteilten die Patienten ihr Befinden mittels Pittsburgh Sleep Quality Index (PSQI) nach Buysse und der Beschwerden-Liste nach von Zerssen (B-L und B-L'). Ergebnisse: Unter der Cardiodoron®-Therapie gingen bei guter Verträglichkeit sowohl die Ausprägung der Schlafstörungen (um 65% von 2,0 auf 0,7 Punkte) als auch die erfassten 30 Symptome (um 59% von 24,3 auf 9,9 Punkte) deutlich zurück (p mit Schlafstörungen (mit oder ohne funktionelle Herz-Kreislauf-Beschwerden) kann die Ausprägung der Beschwerden mit Cardiodoron® deutlich gesenkt werden. Cardiodoron® ist gut verträglich. © 2016 S

  14. [Postoperative adjuvante Therapie mit einem Mistelextrakt (Viscum album ssp. album) bei Hündinnen mit Mammatumoren].

    Science.gov (United States)

    Biegel, Ulrike; Stratmann, Nina; Knauf, Yvonne; Ruess, Katja; Reif, Marcus; Wehrend, Axel

    2017-01-01

    Hintergrund: Canine Mammatumoren (CMT) sind wegen ihrer Häufigkeit und hohen Malignitätsrate eine Herausforderung für die Veterinärmedizin. Bisher ist noch keine postoperative adjuvante Therapie als wirksamer Standard etabliert und in den nächsten Jahren wohl auch nicht zu erwarten. Zusätzlich ist die Frage nach der Verträglichkeit einer adjuvanten Therapie mit Erhaltung oder Verbesserung der Lebensqualität (LQ) wichtig. Die Therapie mit Mistelextrakten (Viscum album L.; VAE) ist in der Humanonkologie nach adjuvanter Tumorbasistherapie (Chemotherapie und Bestrahlung) eine sehr häufig verwendete, zusätzliche adjuvante Behandlungsmethode. Auch bei verschiedenen Tierarten werden inzwischen Mistelpräparate in der Onkologie erfolgreich angewendet. Methoden: Überprüfung von Wirkung und Nutzen einer postoperativen, adjuvanten Misteltherapie beim CMT sowie Erfassung der LQ unter der VAE-Behandlung. Ausgewertet wurden 56 Hündinnen mit Mammaadenokarzinom, 33 ausschließlich operierte Kontrolltiere und 23 operierte Tiere, die adjuvant VAE erhielten. Ergebnisse: Die mediane Überlebenszeit (MST) aller Tiere (n = 56) betrug 32 Monate (Interquartilbereich 13-51 Monate). Im deskriptiven Vergleich der Überlebenszeiten (ST) nach Kaplan-Meier waren nach 12, 24, 36 bzw. 48 Monaten noch 24, 20, 15 bzw. 5 Hündinnen (entsprechend 72,7%, 60,6%, 45,1%, 12,4%) der Kontrollgruppe sowie 19, 14, 11 und 1 Hündin (82,6%, 60,9%, 47,8%, 4,3%) der VAE-Gruppe am Leben. Die VAE-Therapie führte zu einem geringeren Gesamtversterberisiko, das statistisch nicht signifikant war (Hazard Ratio (HR) 0,530, 95%-Konfidenzintervall (KI) 0,222-1,262; p = 0,15). Tendenziell (p = 0,07) zeigte sich eine Verringerung des tumorbedingten Sterberisikos auf 25% (HR 0,251, 95%-KI 0,056-1,122). Schlussfolgerungen: Es kann eine Tendenz zur Senkung des tumorbedingten Sterberisikos der VAE-Gruppe bei guter Verträglichkeit der Therapie angenommen werden. Die LQ der Tiere blieb über die gesamte

  15. Vertebroplasty in osteoporotic vertebral compression; Stellenwert der Vertebroplastie bei osteoporotisch bedingten Wirbelkoerperfrakturen

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, R.T.; Jakobs, T.F.; Ertl-Wagner, B.B.; Wallnoefer, A.; Reiser, M.F.; Helmberger, T.K. [Institut fuer Klinische Radiologie, Klinikum der Universitaet Muenchen-Grosshadern (Germany)

    2003-09-01

    wurden 7 Studien, die den postinterventionellen Verlauf von jeweils mehr als 16 Patienten beschrieben haben und seit 1997 zum Thema Vertebroplastie bei Osteoporose veroeffentlicht wurden, kritisch beurteilt. Die Ergebnisse dieser Studien wurden mit eigenen Ergebnissen an 22 Patienten verglichen, die im Jahr 2002 behandelt wurden. Unmittelbar nach Durchfuehrung der VP wird eine sofortige Linderung der Beschwerden beschrieben. Im weiteren zeitlichen Verlauf werden eine Schmerzreduktion von bis zu 90% und eine deutliche Reduktion des Schmerzmittelbedarfs der betroffenen Patienten in der Literatur berichtet. Im Vergleich dazu konnten wir bei 17 von 22 (77%) von uns 2002 behandelten und evaluierten Patienten eine deutliche Schmerzreduktion erreichen. 18 von 22 Patienten (82%) konnten ihre Schmerzmedikation deutlich reduzieren oder vollstaendig beenden. Insgesamt konnte mit der perkutanen Vertebroplastie die Lebensqualitaet von Patienten, die schmerzhafte osteoporotische Wirbelkoerperfrakturen erlitten haben, nachhaltig verbessert werden. Waehrend der letzten Jahre haben Studien zur perkutanen Vertebroplastie gezeigt, dass ein guter und schneller Behandlungserfolg erreicht werden kann und der Patient einen deutlichen Zugewinn an Lebensqualitaet erfaehrt. (orig.)

  16. Hyperperfusion on Perfusion Computed Tomography Following Revascularization for Acute Stroke

    International Nuclear Information System (INIS)

    Nguyen, T.B.; Lum, C.; Eastwood, J.D.; Stys, P.K.; Hogan, M.; Goyal, M.

    2005-01-01

    Purpose: To describe the findings of hyperperfusion on perfusion computed tomography (CT) in four patients following revascularization for acute stroke. Material and Methods: In 2002-2003, among a series of 6 patients presenting with an acute stroke and treated with intra-arterial thrombolysis, we observed the presence of hyperperfusion in 3 patients on the follow-up CT perfusion. We included an additional patient who was treated with intravenous thrombolysis and who had hyperperfusion on the follow-up CT perfusion. We retrospectively analyzed their CT perfusion maps. Cerebral blood volume (CBV) and cerebral blood flow (CBF) maps were compared between the affected territory and the normal contralateral hemisphere. Results: In the four patients, the mean CBV and CBF were 3.6±2.0 ml/100 g and 39±25 ml/100 g/min in the affected territory compared to the normal side (mean CBV 2.7±2.1 ml/100 g, mean CBF = 27±23 ml/100 g/min). There was no intracranial hemorrhage in the hyperperfused territories. At follow-up CT, some hyperperfused brain areas progressed to infarction, while others retained normal white to gray matter differentiation. Conclusion: CT perfusion can demonstrate hyperperfusion, which can be seen in an ischemic brain territory following recanalization

  17. Magnetic resonance cardiac perfusion imaging-a clinical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Hunold, Peter; Schlosser, Thomas; Barkhausen, Joerg [University Hospital, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany)

    2006-08-15

    Coronary artery disease (CAD) with its clinical appearance of stable or unstable angina and acute myocardial infarction is the leading cause of death in developed countries. In view of increasing costs and the rising number of CAD patients, there has been a major interest in reliable non-invasive imaging techniques to identify CAD in an early (i.e. asymptomatic) stage. Since myocardial perfusion deficits appear very early in the ''ischemic cascade'', a major breakthrough would be the non-invasive quantification of myocardial perfusion before functional impairment might be detected. Therefore, there is growing interest in other, target-organ-specific parameters, such as relative and absolute myocardial perfusion imaging. Magnetic resonance (MR) imaging has been proven to offer attractive concepts in this respect. However, some important difficulties have not been resolved so far, which still causes uncertainty and prevents the broad application of MR perfusion imaging in a clinical setting. This review explores recent technical developments in MR hardware, software and contrast agents, as well as their impact on the current and future clinical status of MR imaging of first-pass myocardial perfusion imaging. (orig.)

  18. Clinical evaluation of non-invasive perfusion-weighted MRI

    International Nuclear Information System (INIS)

    Takasu, Miyuki

    2000-01-01

    A spin labeling method to measure cerebral blood flow without a contrast medium was developed and applied clinically to obtain a non-invasive perfusion-weighted image. The purpose of this study is to compare the non-invasive perfusion-weighted image using FAIR with the well-established PWI using a bolus injection of Gd-DTPA. Of 41 lesions which revealed decreased perfusion, 13 were shown to be low signal intensity areas on FAIR. Therefore, detection rate of FAIR for hypoperfusion was 32%. Of 8 lesions which revealed increased perfusion, 7 demonstrated high intensity on FAIR. Therefore, detection rate of FAIR for hyperperfusion was 88%. Seven lesions were found to have a mean pixel value of zero on PWI. Of these lesions, 5 lesions could be detected as high signal intensity area on FAIR. The rCBV- and rCBF index ratios of hypoperfused lesions detected on FAIR were significantly lower than those of lesions which were not detected on FAIR (p=0.007, p=0.01). As concerns the lesions detected of FAIR, there were positive correlation between rCBV- or rCBF index ratio and FAIR signal ratio (rCBV ratio: ρ=0.873, p=0.0002, rCBF index ratio: ρ=0.858, p=0.0003). FAIR is valuable clinical tool to detect perfusion abnormality semi-quantitatively without contrast medium, although it showed relatively low detection rate for hypoperfused lesions. (author)

  19. Clearing of psoriasis documented by laser Doppler perfusion imaging contrasts remaining elevation of dermal expression levels of CD31

    NARCIS (Netherlands)

    Hendriks, A.G.M.; Kerkhof, P.C.M. van de; Jonge, C.S. de; Lucas, M.; Steenbergen, W.; Seyger, M.M.B.

    2015-01-01

    BACKGROUND: Vascular modifications represent a key feature in psoriatic plaques. Previous research with Laser Doppler Perfusion Imaging (LDPI) revealed a remarkable heterogeneity in the cutaneous perfusion within homogenous-appearing psoriatic lesions. Insights in the relation between perfusion

  20. Effects of Constant Flow vs. Constant Pressure Perfusion on Fluid Filtration in Severe Hypothermic Isolated Blood-Perfused Rat Lungs.

    Science.gov (United States)

    Halsøy, Kathrine; Kondratiev, Timofey; Tveita, Torkjel; Bjertnaes, Lars J

    2016-01-01

    Victims of severe accidental hypothermia are prone to fluid extravasation but rarely develop lung edema. We hypothesize that combined hypothermia-induced increase in pulmonary vascular resistance (PVR) and a concomitant fall in cardiac output protect the lungs against edema development. Our aim was to explore in hypothermic-isolated blood-perfused rat lungs whether perfusion at constant pressure influences fluid filtration differently from perfusion at constant flow. Isolated blood-perfused rat lungs were hanging freely in a weight transducer for measuring weight changes (ΔW). Fluid filtration coefficient (Kfc), was determined by transiently elevating left atrial pressure (Pla) by 5.8 mmHg two times each during normothermia (37°C) and during hypothermia (15°C). The lung preparations were randomized to two groups. One group was perfused with constant flow (Constant flow group) and the other group with constant pulmonary artery pressure (Constant PPA group). Microvascular pressure (Pmv) was determined before and during elevation of Pla (ΔPmv) by means of the double occlusion technique. Kfc was calculated with the formula Kfc = ΔW/ΔPmv/min. All Kfc values were normalized to predicted lung weight (P LW ), which was based on body weight (BW) according to the formula: P LW  = 0.0053 BW - 0.48 and presented as Kfc PLW in mg/min/mmHg/g. At cessation, bronchoalveolar lavage (BAL) fluid/perfusate protein concentration (B/P) ratio was determined photometrically. Data were analyzed with parametric or non-parametric tests as appropriate. p  < 0.05 considered as significant. Perfusate flow remained constant in the Constant flow group, but was more than halved during hypothermia in the Constant PPA group concomitant with a more fold increase in PVR. In the Constant flow group, Kfc PLW and B/P ratio increased significantly by more than 10-fold during hypothermia concerted by visible signs of edema in the trachea. Hemoglobin and hematocrit increased within

  1. 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

    Acceleration-deceleration rotational brain trauma is a common cause of disability or death in young adults and often leads to a focal destruction of axons. The resulting pathology, axonal shear injury is referred to as diffuse axonal injury (DAI). The DAI-associated lesions occur bilaterally, are widely dispersed and have been observed in the surface and deep white matter. They are found near to and far from the impact site. When DAI is clinically suspected, magnetic resonance imaging (MRI) is the method of choice for further clarification, especially in patients where cranial computed tomography (CT) is inconspicuous. To investigate the presence of DAI after traumatic brain injury (TBI), a multimodal MRI approach is applied including the common structural and also functional imaging sequences. For structural MRI, fluid-attenuated inversion recovery (FLAIR) weighted and susceptibility contrast imaging (SWI) are the sequences mainly used. The SWI technique is extremely sensitive to blood breakdown products, which appear as small signal voids at three locations, at the gray-white interface, in the corpus callosum and in the brain stem. Functional MRI comprises a group of constantly developing techniques that have great potential in optimal evaluation of the white matter in patients after craniocerebral trauma. These imaging techniques allow the visualization of changes associated with shear injuries, such as functional impairment of axons and decreased blood flow and abnormal metabolic activity of the brain parts affected. The multimodal MRI approach in patients with DAI results in a more detailed and differentiated representation of the underlying pathophysiological changes of the injured nerve tracts and helps to improve the diagnostic and prognostic accuracy of MRI. When DAI is suspected multimodal MRI should be performed as soon as possible after craniocerebral injury. (orig.) [German] Das Rotationstrauma des Gehirns ist bei jungen Erwachsenen ein haeufiger Grund

  2. Penile angiography and superselective embolization therapy in arterial priapism; Penisangiographie und superselektive Embolisationstherapie bei high-flow Priapismus

    Energy Technology Data Exchange (ETDEWEB)

    Dinkel, H.P.; Triller, J. [Inst. fuer Diagnostische Radiologie, Inselspital, Univ. Bern (Switzerland); Hochreiter, W. [Urologische Klinik, Inselspital, Univ. Bern (Switzerland)

    2003-08-01

    Purpose: To report feasibility, benefit and complications of penile angiography and superselective penile embolization in arterial priapism. Materials and Methods: Four consecutive patients (aged 28, 29, 40 and 49 years), who underwent penile angiography for arterial priapism (high-flow priapism) within a four-year period, were identified by a keyword search of our radiology information system. One patient had sustained a direct penile trauma (severe blow to the erected penis) and three patients suffered from recurrent spontaneous priapism. All patients had previously undergone corporeal aspiration and noradrenaline injection to achieve detumescence. Two patients had one or several unsuccessful spongiocavernous shunt procedures. Results: In three of the four patients, superselective pudendal and penile angiography demonstrated pathologic arteriocavernous shunting. In two of the three patients, superselective embolization using a coaxial micro-catheter was attempted. In one of the two patients, the cavernous artery became spastic before embolization material was actually injected, inducing immediate and lasting detumescence. In the other patient, unilateral Gelfoam embolization led to immediate detumescence but the priapism recurred 12 hours after the procedure. A subsequent contralateral Gelfoam embolization was successful. Erectile function was preserved in all cases. No procedure-related complications occurred. Conclusion: Our experience supports the prevailing opinion found in the current literature that superselective coaxial embolization constitutes the treatment of choice in patients with high-flow priapism. Prognosis is good with high probability of preserving the erectile function. (orig.) [German] Ziel: Untersuchung der Interventionsmoeglichkeiten bei arteriellem (high-flow) Priapismus durch endovaskulaere superselektive Embolisation der Penisarterien. Methode: Alle innerhalb eines Vierjahreszeitraums (1/99-5/2002) wegen Priapismus zur Angiographie

  3. Testosterone biotransformation by the isolated perfused canine pancreas

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-del Castillo, C.; Diaz-Sanchez, V.; Varela-Fascinetto, G.; Altamirano, A.; Odor-Morales, A.; Lopez-Medrano, R.M.; Robles-Diaz, G. (Instituto Nacional de la Nutricion Salvador Zubiran, Mexico City (Mexico))

    1991-01-01

    There is strong evidence indicating that the pancreas is under the influence of sex steroid hormones, and that it may even participate in their biosynthesis and metabolism. In the present study, (3H)testosterone was perfused into the isolated canine pancreas, and measured in the effluent with several of its metabolites (5 alpha-dihydrotestosterone, androstenedione, and estradiol). Results show that testosterone is readily transformed by the canine pancreas. The main product found in the effluent is androstenedione. The testis and spleen were also perfused with (3H)testosterone and used as controls. In both cases, this hormone appeared mostly unchanged in the effluent as compared to the pancreatic perfusion (p less than 0.0001). From our data, we conclude that the canine pancreas has the capacity to transform sex steroid hormones, and could be considered an extragonadal site of sex steroid biosynthesis.

  4. Improved perfusion quantification in FAIR imaging by offset correction

    DEFF Research Database (Denmark)

    Sidaros, Karam; Andersen, Irene Klærke; Gesmar, Henrik

    2001-01-01

    Perfusion quantification using pulsed arterial spin labeling has been shown to be sensitive to the RF pulse slice profiles. Therefore, in Flow-sensitive Alternating-Inversion Recovery (FAIR) imaging the slice selective (ss) inversion slab is usually three to four times thicker than the imaging...... slice. However, this reduces perfusion sensitivity due to the increased transit delay of the incoming blood with unperturbed spins. In the present article, the dependence of the magnetization on the RF pulse slice profiles is inspected both theoretically and experimentally. A perfusion quantification...... model is presented that allows the use of thinner ss inversion slabs by taking into account the offset of RF slice profiles between ss and nonselective inversion slabs. This model was tested in both phantom and human studies. Magn Reson Med 46:193-197, 2001...

  5. Intestinal perfusion in the study of intestinal absorption

    International Nuclear Information System (INIS)

    Baker, S.J.

    1976-01-01

    Several techniques for studying absorption by means of intestinal perfusion have been developed. While the principle is simple, the practice is complicated by absorption of the solvent and by excretion of fluid into the lumen. To improve reliability a ''marker'' is incorporated into the system; it should behave as nearly as possible like the nutrient of interest, except that it should be unabsorbable. A great many markers, including several labelled with radionuclides, have been developed for use with numerous nutrients, and perfusion methods using double or triple tubes or occlusive balloons have been tested. The perfusion technique is too complicated for routine diagnostic use, but it offers at present the only possibility of studying the function of defined sections of the small intestine in the intact human. (author)

  6. Testosterone biotransformation by the isolated perfused canine pancreas

    International Nuclear Information System (INIS)

    Fernandez-del Castillo, C.; Diaz-Sanchez, V.; Varela-Fascinetto, G.; Altamirano, A.; Odor-Morales, A.; Lopez-Medrano, R.M.; Robles-Diaz, G.

    1991-01-01

    There is strong evidence indicating that the pancreas is under the influence of sex steroid hormones, and that it may even participate in their biosynthesis and metabolism. In the present study, [3H]testosterone was perfused into the isolated canine pancreas, and measured in the effluent with several of its metabolites (5 alpha-dihydrotestosterone, androstenedione, and estradiol). Results show that testosterone is readily transformed by the canine pancreas. The main product found in the effluent is androstenedione. The testis and spleen were also perfused with [3H]testosterone and used as controls. In both cases, this hormone appeared mostly unchanged in the effluent as compared to the pancreatic perfusion (p less than 0.0001). From our data, we conclude that the canine pancreas has the capacity to transform sex steroid hormones, and could be considered an extragonadal site of sex steroid biosynthesis

  7. CT of malignant choroidal melanoma - morphology and perfusion characteristics

    International Nuclear Information System (INIS)

    Heller, M.; Hagemann, J.; Jend, H.H.; Guthoff, R.

    1982-01-01

    The computed tomographic morphology of malignant choroidal melanoma and its perfusion characteristics are described. Thirty-three static and serial CT examinations made on 29 patients with choroidal melanoma, three with pseudotumors of the macula and one with choroidal metastasis revealed the choroidal melanoma to be usually a hyperdense, markedly perfused tumor, while the non-contrast, diagnostically undifferentiable pseudotumors and the choroidal metastasis, revealed no significant change in density after the administration of contrast material. Density values or perfusion characteristics of choroidal melanoma that are outside of the normal range are a result of secondary changes within the immediate surroundings of the tumor, such as detachment of the retina, tumor-induced glaucoma, or tumor necrosis. (orig.)

  8. Associations between muscle perfusion and symptoms in knee osteoarthritis

    DEFF Research Database (Denmark)

    Bandak, E; Boesen, M; Bliddal, H

    2015-01-01

    a relatively rapid decline (washout pattern) relative to the total number of voxels within the muscle VOI. CONCLUSIONS: More widespread perfusion in the peri-articular knee muscles was associated with less pain in patients with KOA. These results give rise to investigations of the effects of exercise on muscle......OBJECTIVE: To investigate the association between muscle perfusion in the peri-articular knee muscles assessed by dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) and symptoms in patients with knee osteoarthritis (KOA). DESIGN: In a cross-sectional setting, muscle perfusion...... was quantified by DCE-MRI in KOA. Regions of interest (ROI) were drawn around the peri-articular muscles, summed and averaged into one single "Total Muscle Volume" volume of interest (VOI). Symptoms were assessed via the Knee injury and Osteoarthritis Outcome Score (KOOS) (0: worst; 100: best). RESULTS: DCE...

  9. CT of malignant choroidal melanoma - morphology and perfusion characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Heller, M.; Hagemann, J.; Jend, H.H.; Guthoff, R.

    1982-03-01

    The computed tomographic morphology of malignant choroidal melanoma and its perfusion characteristics are described. Thirty-three static and serial CT examinations made on 29 patients with choroidal melanoma, three with pseudotumors of the macula and one with choroidal metastasis revealed the choroidal melanoma to be usually a hyperdense, markedly perfused tumor, while the non-contrast, diagnostically undifferentiable pseudotumors and the choroidal metastasis, revealed no significant change in density after the administration of contrast material. Density values or perfusion characteristics of choroidal melanoma that are outside of the normal range are a result of secondary changes within the immediate surroundings of the tumor, such as detachment of the retina, tumor-induced glaucoma, or tumor necrosis.

  10. [Studying cerebral perfusion using magnetic susceptibility techniques: technique and applications].

    Science.gov (United States)

    Guzmán-de-Villoria, J A; Fernández-García, P; Mateos-Pérez, J M; Desco, M

    2012-01-01

    Perfusion MRI makes it possible to evaluate the cerebral microvasculature through changes in signal due to a tracer passing through blood vessels. The most commonly used technique is based on the magnetic susceptibility of gadolinium in T2*-weighted sequences, and the most commonly evaluated parameters are cerebral blood volume, cerebral blood flow, and mean transit time. Diverse technical aspects, like the sequence used, and the dose and speed of contrast material injection, must be taken into account in perfusion MRI studies. It is also essential to consider possible sources of error like contrast material leaks due to changes in the permeability of the blood-brain barrier. The most widely used clinical applications of perfusion MRI include the determination of the degree of aggressiveness of gliomas, the differentiation of some histological types of tumors or pseudotumors, and the evaluation of the penumbral area in acute ischemia. Copyright © 2011 SERAM. Published by Elsevier Espana. All rights reserved.

  11. Phase correction of MR perfusion/diffusion images

    International Nuclear Information System (INIS)

    Chenevert, T.L.; Pipe, J.G.; Brunberg, J.A.; Yeung, H.N.

    1989-01-01

    Apparent diffusion coefficient (ADC) and perfusion MR sequences are exceptionally sensitive to minute motion and, therefore, are prone to bulk motions that hamper ADC/perfusion quantification. The authors have developed a phase correction algorithm to substantially reduce this error. The algorithm uses a diffusion-insensitive data set to correct data that are diffusion sensitive but phase corrupt. An assumption of the algorithm is that bulk motion phase shifts are uniform in one dimension, although they may be arbitrarily large and variable from acquisition to acquisition. This is facilitated by orthogonal section selection. The correction is applied after one Fourier transform of a two-dimensional Fourier transform reconstruction. Imaging experiments on rat and human brain demonstrate significant artifact reduction in ADC and perfusion measurements

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-01-01

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

  13. Guidelines for bone scintigraphy in children; Empfehlungen zur Knochenszintigraphie bei Kindern

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, K.; Fischer, S. [LMU Muenchen (Germany). Klinik fuer Nuklearmedizin; Colarinha, P. [Instituto Portugues de Oncologia, Lisbon (Portugal); Gordon, I. [Great Osmond Street Hospital for Children, London (United Kingdom); Mann, M. [Red Cross Hospital, Cape Town (South Africa); Piepsz, A. [AZ VUB and CHU St. Pierre, Brussels (Belgium); Olivier, P. [CHU Vandoeuvre, Nancy (France); Sixt, R. [The Queen Silvia Children' s Hospital, Goeteborg (Sweden); Velzen, J. van

    2000-11-01

    The guidelines are intended to help nuclear medical teams in their daily routine. The guidelines give information relating to indications, performance of examinations, analysis and interpretation of the diagnostic results. The guidelines should be applied in the context of adopted basic quality criteria in nuclear medicine, requirements of the German radiation protection ordinance, as well as the regulatory codes for radiation protection in the medical field. The guidelines express the opinions of the Paediatric Committee of the EANM and hence focus on compliance with the relevant European standards in nuclear medicine. In order to enhance the specificity of results obtained with a bone scintigraphy, the interpretation of the results should be based on combined analysis with information drawn from X-rays. (orig./CB) [German] Zweck dieser Leitlinie ist es, dem nuklearmedizinischen Team eine Hilfe fuer die taegliche Praxis anzubieten. Diese Leitlinie enthaelt Informationen ueber die Indikationen, die Untersuchungsdurchfuehrung, Auswertung und Interpretation von Knochenszintigraphien bei Kindern. Sie sollte in Verbindung mit den ueblichen Qualitaetskriterien in der Nuklearmedizin und den Vorschriften der Strahlenschutzverordnung sowie der Richtlinie Strahlenschutz in der Medizin gesehen werden. Sie fasst die Meinung des Paediatric Committee der EANM zusammen und ist daher in einzelnen Bereichen mehr dem europaeischen Standard der Nuklearmedizin angepasst. Um die Spezifitaet der Knochenszintigraphie zu erhoehen, sollte immer eine gemeinsame Interpretation von Knochenszintigraphie und Roentgenbildern erfolgen. (orig.)

  14. REAKSI PASAR MODAL INDONESIA TERHADAP PERGANTIAN MENTERI KEUANGAN (EVENT STUDY SAHAM YANG TERDAFTAR DI BEI

    Directory of Open Access Journals (Sweden)

    Lia Nur Islami

    2012-02-01

    Full Text Available Information is the main needs of investors in capital markets. Sri Mulyani setback Event of the positions for the finance minister who has information content relevant to investors will cause the market reaction reflected through changes in stock prices and trading activity. This reaction can be measured by indicators of Abnormal Return (AR, Trading Volume Activity (TVA and Security Return variability (SRV. This research is a study of events that aims to find empirical evidence for the existence of the Indonesian capital market reaction to the events of Sri Mulyani setback from the office of finance minister. The population in this study is that all stocks listed on the BEI. While the sample taken through purposive sampling technique of shares - shares that are included in LQ45 corporate action and do not perform during the event period. One sample t-test (one sample t-test was used to analyze whether the AR, TVA, and SRV significant value on the day - the day around the occurrence of events that prove the existence of market reaction. TVA and AR significant at the time of announcement of events shows that the market reacted to the setback Sri Mulyani finance minister from office. However, the SRV is not significant at the time of announcement of events shows that the market reaction that occurs there is an uneven distribution of information and influence the distribution of stock return

  15. [COPD und Klangtherapie: Pilotstudie zur Wirksamkeit einer Behandlung mit Körpertambura bei COPD-Patienten].

    Science.gov (United States)

    Hartwig, Bernhard; Schmidt, Stefan; Hartwig, Isabella

    2016-01-01

    Hintergrund: Erkrankungen der Atemorgane treten mit steigendem Alter öfter auf, nehmen weltweit zu und sind häufige Ursachen für Morbidität und Mortalität. In dieser Pilotstudie wurde der Frage nachgegangen, ob eine einmalige 10-minütige Behandlung mit einer Körpertambura eine signifikante und effektive Verbesserung der Lungenfunktion von Patienten mit chronisch-obstruktiver Lungenerkrankung (COPD; GOLD-Stadium A oder B) erbringen kann. Patienten und Methoden: 54 Probanden konnten je zur Hälfte in eine Behandlungsgruppe (Körpertambura) und eine aktive Kontrollgruppe (Atemtherapie) randomisiert werden. Eine Bestimmung der Lungenfunktionsmessparameter «Einsekundenkapazität» (FEV1) und «inspiratorische Vitalkapazität» (IVC) zu den Zeitpunkten T1 (Baseline), T2 (direkt nach Behandlung) und als Follow-up etwa 3 Wochen nach T1 (T3). Ergebnisse: Die Behandlungsgruppe zeigte sich der Kontrollgruppe in beiden Werten signifikant überlegen. Die Zeit-×-Gruppe-Interaktion (Varianzanalyse) ergab p = 0,001 (FEV1) bzw. p = 0,04 (IVC). Die Behandlungsgruppe zeigte bei beiden Werten eine Verbesserung von klinischer Relevanz. Schlussfolgerung: Diese Ergebnisse zeigen, dass die Klangbehandlung mittels einer Körpertambura - neben den schulmedizinischen, leitliniengerechten Therapien - eine zusätzliche, nebenwirkungsarme, aber durchaus klinisch wirksame Option für die Behandlung von COPD-Patienten darstellen kann, um deren Lebensqualität zu stabilisieren und zu verbessern. © 2016 S. Karger GmbH, Freiburg.

  16. Estimating Zenith Tropospheric Delays from BeiDou Navigation Satellite System Observations

    Directory of Open Access Journals (Sweden)

    Xin Sui

    2013-04-01

    Full Text Available The GNSS derived Zenith Tropospheric Delay (ZTD plays today a very critical role in meteorological study and weather forecasts, as ZTDs of thousands of GNSS stations are operationally assimilated into numerical weather prediction models. Recently, the Chinese BeiDou Navigation Satellite System (BDS was officially announced to provide operational services around China and its neighborhood and it was demonstrated to be very promising for precise navigation and positioning. In this contribution, we concentrate on estimating ZTD using BDS observations to assess its capacity for troposphere remote sensing. A local network which is about 250 km from Beijing and comprised of six stations equipped with GPS- and BDS-capable receivers is utilized. Data from 5 to 8 November 2012 collected on the network is processed in network mode using precise orbits and in Precise Point Positioning mode using precise orbits and clocks. The precise orbits and clocks are generated from a tracking network with most of the stations in China and several stations around the world. The derived ZTDs are compared with that estimated from GPS data using the final products of the International GNSS Service (IGS. The comparison shows that the bias and the standard deviation of the ZTD differences are about 2 mm and 5 mm, respectively, which are very close to the differences of GPS ZTD estimated using different software packages.

  17. Estimating zenith tropospheric delays from BeiDou navigation satellite system observations.

    Science.gov (United States)

    Xu, Aigong; Xu, Zongqiu; Ge, Maorong; Xu, Xinchao; Zhu, Huizhong; Sui, Xin

    2013-04-03

    The GNSS derived Zenith Tropospheric Delay (ZTD) plays today a very critical role in meteorological study and weather forecasts, as ZTDs of thousands of GNSS stations are operationally assimilated into numerical weather prediction models. Recently, the Chinese BeiDou Navigation Satellite System (BDS) was officially announced to provide operational services around China and its neighborhood and it was demonstrated to be very promising for precise navigation and positioning. In this contribution, we concentrate on estimating ZTD using BDS observations to assess its capacity for troposphere remote sensing. A local network which is about 250 km from Beijing and comprised of six stations equipped with GPS- and BDS-capable receivers is utilized. Data from 5 to 8 November 2012 collected on the network is processed in network mode using precise orbits and in Precise Point Positioning mode using precise orbits and clocks. The precise orbits and clocks are generated from a tracking network with most of the stations in China and several stations around the world. The derived ZTDs are compared with that estimated from GPS data using the final products of the International GNSS Service (IGS). The comparison shows that the bias and the standard deviation of the ZTD differences are about 2 mm and 5 mm, respectively, which are very close to the differences of GPS ZTD estimated using different software packages.

  18. Preface: BeiDou Navigation Satellite System (BDS)/GNSS+: New developments and emerging applications

    Science.gov (United States)

    Jin, Shuanggen

    2017-12-01

    The China's BeiDou Navigation Satellite System (BDS) has been developed and operated well with over 25 launched satellites in 2017, including fifteen Medium Earth orbit (MEO) satellites, five geostationary Earth orbit (GEO) satellites and five inclined geosynchronous orbit (IGSO) satellites. Together with the United States' GPS, European Union's Galileo and Russia's GLONASS as well as other regional augmentation systems, e.g., Indian Regional Navigation Satellite System (IRNSS) and Japan Quasi-Zenith Satellite System (QZSS), more emerging applications of multi-Global Navigation Satellite Systems (GNSS) will be exploited and realized in the coming years. The papers in this issue of Advances in Space Research present new advances in the system, techniques and emerging applications of BDS/GNSS+. These papers were from an open call and a special call for participants at the 8th China Satellite Navigation Conference (CSNC 2017) held on May 23-25, 2017, Shanghai, China. This conference series provides a good platform for academic and technique exchanges as well as collaboration in satellite navigation. CSNC 2017 was well attend with more than 3000 participants and over 800 papers in 12 sessions.

  19. Characterizing potential heart agents with an isolated perfused heart system

    International Nuclear Information System (INIS)

    Pendleton, D.B.; Sands, H.; Gallagher, B.M.; Camin, L.L.

    1984-01-01

    The authors have used an isolated perfused heart system for characterizing potential myocardial perfusion radiopharamaceuticals. Rabbit or guinea pig (GP) hearts are removed and perfused through the aorta with a blood-free buffer. Heart rate and ventricular pressure are monitored as indices of viability. Tc-99m-MAA is 96-100% retained in these hearts, and Tc-99m human serum albumin shows less than 5% extraction. Tl-201 is 30-40% extracted. It is known that in-vivo, Tc-99m(dmpe)/sub 2/Cl/sub 2//sup +/ is taken up by rabbit heart but not by GP or human heart. Analogous results are obtained with the isolated perfused heart model, where the complex is extracted well by the isolated rabbit heart (24%) but not by the GP heart (<5%). Values are unchanged if human, rabbit or GP blood is mixed and co-injected with the complex. Tc-99m)dmpe)/sub 3//sup +/ is also taken up by rabbit but not by GP hearts in-vivo. However, isolated perfused hearts of both species extract this complex well (45-52%). Heart uptake is diminished to <7% if the complex is pre-equilibrated with human blood. GP blood produces a moderate inhibition (in GP hearts only) and rabbit blood has no effect. This suggests that a human or GP blood factor may have a significant effect on heart uptake of this complex. Tc-99m(CN-t-butyl)/sub 6//sup +/ is taken up well by both rabbit and GP hearts in-vivo, and is extracted 100% by both isolated perfused hearts. Heart retention remains high (73-75%) in the presence of human blood

  20. A 4D Digital Phantom for Patient-Specific Simulation of Brain CT Perfusion Protocols

    NARCIS (Netherlands)

    Boom, R. van den; Manniesing, R.; Oei, M.T.H.; Woude, W.J. van der; Smit, E.J.; Laue, H.O.A.; Ginneken, B. van; Prokop, M.

    2014-01-01

    Purpose Optimizing CT brain perfusion protocols is a challenge because of the complex interaction between image acquisition, calculation of perfusion data and patient hemodynamics. Several digital phantoms have been developed to avoid unnecessary patient exposure or suboptimum choice of parameters.

  1. Evolution of peripheral vs metabolic perfusion parameters during septic shock resuscitation. A clinical-physiologic study

    NARCIS (Netherlands)

    Hernandez, Glenn; Pedreros, Cesar; Veas, Enrique; Bruhn, Alejandro; Romero, Carlos; Rovegno, Maximiliano; Neira, Rodolfo; Bravo, Sebastian; Castro, Ricardo; Kattan, Eduardo; Ince, Can

    2012-01-01

    Purpose: Perfusion assessment during septic shock resuscitation is difficult and usually complex determinations. Capillary refill time (CRT) and central-to-toe temperature difference (Tc-toe) have been proposed as objective reproducible parameters to evaluate peripheral perfusion. The comparative

  2. Pediatric hemiplegic migraine: susceptibility weighted and MR perfusion imaging abnormality

    International Nuclear Information System (INIS)

    Altinok, Deniz; Agarwal, Ajay; Ascadi, Gyula; Luat, Aimee; Tapos, Daniela

    2010-01-01

    We report on an 11-year-old girl suffering from a typical attack of hemiplegic migraine with characteristic abnormalities in perfusion MR and susceptibility-weighted MR imaging findings. The imaging abnormalities were resolved 48 h after the attack. Susceptibility-weighted MR imaging findings correlated well with the MR perfusion, thus it can be used along with conventional MRI for evaluation of children with complex migraine attacks. Susceptibility-weighted MR imaging might have a diagnostic role in assessing the vascular events in hemiplegic migraine. (orig.)

  3. The diagnosis of renal perfusion abnormalities by sequential CT

    International Nuclear Information System (INIS)

    Treugut, H.; Andersson, I.; Hildell, J.; Nyman, U.; Weibull, H.

    1981-01-01

    Abnormalities of renal perfusion can be recognised more readily by sequential CT than by plain CT scan or after static enhancement with contrast medium. Haemodynamically significant stenoses of the renal arteries and total, or partial, infarcts can be diagnosed in this way. Intrarenal and capsular collaterals can be recognised by slow contrast accumulation in the infarcted area, or by the development of contrast in the sub-capsular portion of the cortex. Renal cortical necrosis is very well demonstrated by the absence of cortical perfusion; this is seen, for instance, in the DIC syndrome or during rejection after renal transplant. (orig.) [de

  4. Perfusion monitoring and intraventricular hemorrhage in preterm infants.

    Science.gov (United States)

    Ishiguro, Akio

    2017-07-01

    Cardiovascular instability in preterm infants during the early postnatal period correlates with the development of intraventricular hemorrhage (IVH). Due to the correlation between hypotension and fluctuation of blood pressure, treatment was targeted specifically at hypotension to prevent IVH, but this was not successful. Recently, several novel perfusion markers have been found to be correlated with the development of IVH, and they are of current interest in cardiovascular management. In this review, the correlation between IVH and conventional, as well as novel, perfusion markers is examined. © 2017 Japan Pediatric Society.

  5. Ventilation-perfusion lung imaging in diaphragmatic paralysis

    International Nuclear Information System (INIS)

    Chopra, S.K.; Taplin, G.V.

    1977-01-01

    Clinical, radiological, physiological, and lung imaging findings from a patient with paralysis of the diaphragm are described. Dyspnea, hypoxemia and hypercapnia increased when the patient changed from the upright to the supine positions. Ventilation (V) and perfusion (P) images of the right lung appeared to be relatively normal and remained nearly the same in the upright and supine positions. In contrast, V/P images of the left lung were smaller than those of the right lung in the upright position and decreased further in the supine position. In addition, the size of the ventilation image was much smaller than that of the perfusion

  6. Pancreas tumor model in rabbit imaged by perfusion CT scans

    Science.gov (United States)

    Gunn, Jason; Tichauer, Kenneth; Moodie, Karen; Kane, Susan; Hoopes, Jack; Stewart, Errol E.; Hadway, Jennifer; Lee, Ting-Yim; Pereira, Stephen P.; Pogue, Brian W.

    2013-03-01

    The goal of this work was to develop and validate a pancreas tumor animal model to investigate the relationship between photodynamic therapy (PDT) effectiveness and photosensitizer drug delivery. More specifically, this work lays the foundation for investigating the utility of dynamic contrast enhanced blood perfusion imaging to be used to inform subsequent PDT. A VX2 carcinoma rabbit cell line was grown in the tail of the pancreas of three New Zealand White rabbits and approximately 3-4 weeks after implantation the rabbits were imaged on a CT scanner using a contrast enhanced perfusion protocol, providing parametric maps of blood flow, blood volume, mean transit time, and vascular permeability surface area product.

  7. Pancreatic Perfusion CT in Early Stage of Severe Acute Pancreatitis

    Directory of Open Access Journals (Sweden)

    Yoshihisa Tsuji

    2012-01-01

    Full Text Available Early intensive care for severe acute pancreatitis is essential for improving SAP mortality rates. However, intensive therapies for SAP are often delayed because there is no ideal way to accurately evaluate severity in the early stages. Currently, perfusion CT has been shown useful to predict prognosis of SAP in the early stage. In this presented paper, we would like to review the clinical usefulness and limitations of perfusion CT for evaluation of local and systemic complications in early stage of SAP.

  8. Reactivity of the isolated perfused rat tail vascular bed

    Directory of Open Access Journals (Sweden)

    A.S. França

    1997-07-01

    Full Text Available Isolated segments of the perfused rat tail artery display a high basal tone when compared to other isolated arteries such as the mesenteric and are suitable for the assay of vasopressor agents. However, the perfusion of this artery in the entire tail has not yet been used for functional studies. The main purpose of the present study was to identify some aspects of the vascular reactivity of the rat tail vascular bed and validate this method to measure vascular reactivity. The tail severed from the body was perfused with Krebs solution containing different Ca2+ concentrations at different flow rates. Rats were anesthetized with sodium pentobarbital (65 mg/kg and heparinized (500 U. The tail artery was dissected near the tail insertion, cannulated and perfused with Krebs solution plus 30 µM EDTA at 36oC and 2.5 ml/min and the procedures were started after equilibration of the perfusion pressure. In the first group a dose-response curve to phenylephrine (PE (0.5, 1, 2 and 5 µg, bolus injection was obtained at different flow rates (1.5, 2.5 and 3.5 ml/min. The mean perfusion pressure increased with flow as well as PE vasopressor responses. In a second group the flow was changed (1.5, 2, 2.5, 3 and 3.5 ml/min at different Ca2+ concentrations (0.62, 1.25, 2.5 and 3.75 mM in the Krebs solution. Increasing Ca2+ concentrations did not alter the flow-pressure relationship. In the third group a similar protocol was performed but the rat tail vascular bed was perfused with Krebs solution containing PE (0.1 µg/ml. There was an enhancement of the effect of PE with increasing external Ca2+ and flow. PE vasopressor responses increased after endothelial damage with air and CHAPS, suggesting an endothelial modulation of the tone of the rat tail vascular bed. These experiments validate the perfusion of the rat tail vascular bed as a method to investigate vascular reactivity

  9. Skin Blood Perfusion and Oxygenation Colour Affect Perceived Human Health

    Science.gov (United States)

    Stephen, Ian D.; Coetzee, Vinet; Law Smith, Miriam; Perrett, David I.

    2009-01-01

    Skin blood perfusion and oxygenation depends upon cardiovascular, hormonal and circulatory health in humans and provides socio-sexual signals of underlying physiology, dominance and reproductive status in some primates. We allowed participants to manipulate colour calibrated facial photographs along empirically-measured oxygenated and deoxygenated blood colour axes both separately and simultaneously, to optimise healthy appearance. Participants increased skin blood colour, particularly oxygenated, above basal levels to optimise healthy appearance. We show, therefore, that skin blood perfusion and oxygenation influence perceived health in a way that may be important to mate choice. PMID:19337378

  10. Cerebral perfusion deficits in divers with neurological decompression illness

    International Nuclear Information System (INIS)

    Wilmshurst, P.T.; O'Doherty, M.J.; Nunan, T.O.

    1993-01-01

    Cerebral perfusion deficits detected by injection of 99 Tc m -hexamethylpropyleneamine oxime (HMPAO) and single photon emission tomography is said to correlate well with clinical findings in divers with neurological decompression illness. We studied 12 divers. Six had residual cerebral signs (group 1) and six had no residual cerebral symptoms or signs (group 2). Perfusion deficits were as common in group 2 as in group 1. The site of the deficit did not correlate well with either the neurological findings at presentation or the residual clinical signs after treatment. The data suggest that claims that HMPAO scanning correlates with clinical findings and can be used for patient management were incorrect. (author)

  11. Prognostic Value of Quantitative Stress Perfusion Cardiac Magnetic Resonance.

    Science.gov (United States)

    Sammut, Eva C; Villa, Adriana D M; Di Giovine, Gabriella; Dancy, Luke; Bosio, Filippo; Gibbs, Thomas; Jeyabraba, Swarna; Schwenke, Susanne; Williams, Steven E; Marber, Michael; Alfakih, Khaled; Ismail, Tevfik F; Razavi, Reza; Chiribiri, Amedeo

    2017-11-10

    This study sought to evaluate the prognostic usefulness of visual and quantitative perfusion cardiac magnetic resonance (CMR) ischemic burden in an unselected group of patients and to assess the validity of consensus-based ischemic burden thresholds extrapolated from nuclear studies. There are limited data on the prognostic value of assessing myocardial ischemic burden by CMR, and there are none using quantitative perfusion analysis. Patients with suspected coronary artery disease referred for adenosine-stress perfusion CMR were included (n = 395; 70% male; age 58 ± 13 years). The primary endpoint was a composite of cardiovascular death, nonfatal myocardial infarction, aborted sudden death, and revascularization after 90 days. Perfusion scans were assessed visually and with quantitative analysis. Cross-validated Cox regression analysis and net reclassification improvement were used to assess the incremental prognostic value of visual or quantitative perfusion analysis over a baseline clinical model, initially as continuous covariates, then using accepted thresholds of ≥2 segments or ≥10% myocardium. After a median 460 days (interquartile range: 190 to 869 days) follow-up, 52 patients reached the primary endpoint. At 2 years, the addition of ischemic burden was found to increase prognostic value over a baseline model of age, sex, and late gadolinium enhancement (baseline model area under the curve [AUC]: 0.75; visual AUC: 0.84; quantitative AUC: 0.85). Dichotomized quantitative ischemic burden performed better than visual assessment (net reclassification improvement 0.043 vs. 0.003 against baseline model). This study was the first to address the prognostic benefit of quantitative analysis of perfusion CMR and to support the use of consensus-based ischemic burden thresholds by perfusion CMR for prognostic evaluation of patients with suspected coronary artery disease. Quantitative analysis provided incremental prognostic value to visual assessment and

  12. Myocardial perfusion scintigraphy with exercise and pharmacological stress

    International Nuclear Information System (INIS)

    Sundram, F.X.

    1995-01-01

    Cardiac studies including myocardial perfusion scintigraphy was begun in the Singapore General Hospital, nuclear medicine department in 1983. From a few patients per year using planar imaging, we have in 1994 studied 1500 patients for myocardial perfusion, using mainly SPECT (single-photon emission computerised tomography) and radionuclides such as Thallium-201, Technetium-99m sestamibi and Tc-99m tetrofosmin. Patients have been stressed using treadmill exercise or pharmacological agents; we have used dipyridamole, and dobutamine for pharmacological stress but have no experience with intravenous adenosine

  13. Direct myocardial perfusion imaging in valvular heart disease

    International Nuclear Information System (INIS)

    Soto, R.C.; Durante, M.L.; Villacorta, E.V.; Torres, J.F.; Monzon, O.P.

    1981-01-01

    Twenty two patients with rheumatic valvular heart disease - 21 having a history of heart failure - were studied using direct coronary injection of sup(99m)Tc labelled MAA particles during the course of hemodynamic and arteriographic studies. Myocardial perfusion deficit patterns have been shown to be consistent or indicative of either patchy, regional or gross ischemia. In patients with history of documented heart failure 90% (18 cases) had ischemic perfusion deficit in the involved ventricle. We conclude that diminished myocardial blood flow is an important mechanism contributing to the development of heart failure. (orig.) [de

  14. Diagnostic Performance of Dual-Energy CT Stress Myocardial Perfusion Imaging: Direct Comparison With Cardiovascular MRI

    Science.gov (United States)

    Ko, Sung Min; Song, Meong Gun; Chee, Hyun Kun; Hwang, Hweung Kon; Feuchtner, Gudrun Maria; Min, James K.

    2014-01-01

    OBJECTIVE The purpose of this study was to assess the diagnostic performance of stress perfusion dual-energy CT (DECT) and its incremental value when used with coronary CT angiography (CTA) for identifying hemodynamically significant coronary artery disease. SUBJECTS AND METHODS One hundred patients with suspected or known coronary artery disease without chronic myocardial infarction detected with coronary CTA underwent stress perfusion DECT, stress cardiovascular perfusion MRI, and invasive coronary angiography (ICA). Stress perfusion DECT and cardiovascular stress perfusion MR images were used for detecting perfusion defects. Coronary CTA and ICA were evaluated in the detection of ≥ 50% coronary stenosis. The diagnostic performance of coronary CTA for detecting hemodynamically significant stenosis was assessed before and after stress perfusion DECT on a pervessel basis with ICA and cardiovascular stress perfusion MRI as the reference standard. RESULTS The performance of stress perfusion DECT compared with cardiovascular stress perfusion MRI on a per-vessel basis in the detection of perfusion defects was sensitivity, 89%; specificity, 74%; positive predictive value, 73%; negative predictive value, 90%. Per segment, these values were sensitivity, 76%; specificity, 80%; positive predictive value, 63%; and negative predictive value, 88%. Compared with ICA and cardiovascular stress perfusion MRI per vessel territory the sensitivity, specificity, positive predictive value, and negative predictive value of coronary CTA were 95%, 61%, 61%, and 95%. The values for stress perfusion DECT were 92%, 72%, 68%, and 94%. The values for coronary CTA and stress perfusion DECT were 88%, 79%, 73%, and 91%. The ROC AUC increased from 0.78 to 0.84 (p = 0.02) with the use of coronary CTA and stress perfusion DECT compared with coronary CTA alone. CONCLUSION Stress perfusion DECT plays a complementary role in enhancing the accuracy of coronary CTA for identifying hemodynamically

  15. Whole body perfusion for hybrid aortic arch repair: evolution of selective regional perfusion with a modified extracorporeal circuit.

    Science.gov (United States)

    Fernandes, Philip; Walsh, Graham; Walsh, Stephanie; O'Neil, Michael; Gelinas, Jill; Chu, Michael W A

    2017-04-01

    Patients undergoing hybrid aortic arch reconstruction require careful protection of vital organs. We believe that whole body perfusion with tailored dual circuitry may help to achieve optimal patient outcomes. Our circuit has evolved from a secondary circuit utilizing a cardioplegia delivery device for lower body perfusion to a dual-oxygenator circuit. This allows individually controlled regional perfusion with ease of switching from secondary to primary circuit for total body flow. The re-design allows for separate flow and temperature regulation with two oxygenators in parallel. All patients underwent a single-stage operation for simultaneous treatment of arch and descending aortic pathology via a sternotomy, using a hybrid frozen elephant trunk technique. We report six consecutive patients undergoing hybrid arch and frozen elephant trunk reconstruction using a dual-oxygenator circuit. Five patients underwent elective surgery and one was emergent. One patient had an acute dissection while three underwent concomitant procedures, including a Ross procedure and two valve-sparing root reconstructions. Three cases were redo sternotomies. The mean pump time was 358 ± 131 min, the aortic cross clamp time 243 ± 135 min, the cardioplegia volume of 33,208 ml ± 16,173, cerebral ischemia 0 min, lower body ischemia 76 ± 34 min and the average lower body perfusion time was 142 min. Two patients did not require any donor blood products. The median intensive care unit (ICU) and hospital lengths of stay (LOS) were two days and 10 days, respectively. The average peak serum lactate on CPB was 7.47 mmol/L and, at admission to the ICU, it was 3.37 mmol/L. Renal and respiratory failure developed in the salvage acute type A dissection patient. No other complications occurred in this series. Whole body perfusion as delivered through individually controlled dual-oxygenator circuitry allows maximum flexibility for hybrid aortic arch reconstruction. A modified circuit perfusion

  16. Reduced myocardial perfusion reserve and transmural perfusion gradient in heart transplant arteriopathy assessed by magnetic resonance imaging.

    Science.gov (United States)

    Muehling, Olaf M; Wilke, Norbert M; Panse, Prasad; Jerosch-Herold, Michael; Wilson, Betsy V; Wilson, Robert F; Miller, Leslie W

    2003-09-17

    The goal of this study was to detect transplant arteriopathy (Tx-CHD) by a reduced myocardial perfusion reserve (MPR) and resting endomyocardial/epimyocardial perfusion ratio (Endo/Epi ratio). Transplant arteriopathy often lacks clinical symptoms and is the reason for frequent surveillance angiography in heart transplant (Tx) recipients. Magnetic resonance perfusion imaging (MRPI) allows noninvasive assessment of transmural and selective endomyocardial and epimyocardial perfusion. Fifteen healthy volunteers (controls) and three groups (A, B, C) of Tx recipients were included. In controls and patients, MPR (hyperemic/resting perfusion) and Endo/Epi ratio were determined with MRPI after injection of gadolinium-diethylenetriamine pentaacetic acid at rest and during hyperemia (intravenous adenosine). Group A (n = 10) had no left ventricular (LV) hypertrophy and/or prior rejection, while patients in group B (n = 10) had at least one of these characteristics. Patients in group A and B had a normal coronary angiogram and a coronary flow reserve (CFR) of > or =2.5 (CFR = hyperemic/resting blood flow). Group C (n = 7) had Tx-CHD diagnosed by angiography and a reduced CFR (2.3 with sensitivity and specificity of 100% and 85%. If LV hypertrophy and prior rejection are excluded, Tx-CHD can be excluded by an Endo/Epi ratio of >1.3 with 100% and 80%. Magnetic resonance perfusion imaging detects Tx-CHD by a decreased MPR. After exclusion of LV hypertrophy and prior rejection, resting Endo/Epi ratio alone might be sufficient to indicate Tx-CHD.

  17. Large cerebral perfusion defects observed in brain perfusion SPECT may herald psychiatric or neurodegenerative diseases of transient global amnesia patients

    Energy Technology Data Exchange (ETDEWEB)

    So, Young; Kim, Hahn Young; Roh, Hong Gee; Han, Seol Heui [Konkuk University School of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    Transient global amnesia (TGA) is a memory disorder characterized by an episode of antegrade amnesia and bewilderment which persists for several hours. We analyzed brain perfusion SPECT findings and clinical outcome of patients who suffered from TGA. From September 2005 to August 2007, 12 patients underwent Tc-99m ECD brain perfusion SPECT for neuroimaging of TGA. All patients also underwent MRI and MRA including DWI (MRI). Among them, 10 patients who could be chased more than 6 months were included in this study. Their average age was 60.74.0 yrs (M: F = 2: 8) and the average duration of amnesia was 4.42.2 hrs (1 hr {approx} 7 hrs). Duration from episode of amnesia to SPECT was 4.32.4 days (1{approx}9 days). Precipitating factors could be identified in 6 patients: emotional stress 3, hair dyeing 1, taking a nap 1 and angioplasty 1. SPECT and MRI was visually assessed, No cerebral perfusion defect was observed on SPECT in 3 patients and their clinical outcome was all good. Among 7 patients who had cerebral perfusion defects on SPECT, 3 patients had good clinical outcome, while others did not: one had hypercholesterolemia, another had depression, and 2 patients with cerebral perfusion defects at both temporoparetal cortex was later diagnosed as early Alzheimer's disease (AD) and mild cognitive impairment (MCI). MRI was negative in 6 patients and 3 of them had excellent clinical outcome while other 3 were diagnosed as hypercholesterolemia, early AD and MCI. Among 4 patients with positive MRI, 3 showed good clinical outcome and their MRI showed lesions at medial temporal cortex and/or vertebral artery. One patient with microcalcification at left putamen was diagnosed to have depression. Large cerebral perfusion defects on SPECT may herald psychiatric or neurodegenerative diseases of transient global amnesia patients which usually shows negative MRI.

  18. Large cerebral perfusion defects observed in brain perfusion SPECT may herald psychiatric or neurodegenerative diseases of transient global amnesia patients

    International Nuclear Information System (INIS)

    So, Young; Kim, Hahn Young; Roh, Hong Gee; Han, Seol Heui

    2007-01-01

    Transient global amnesia (TGA) is a memory disorder characterized by an episode of antegrade amnesia and bewilderment which persists for several hours. We analyzed brain perfusion SPECT findings and clinical outcome of patients who suffered from TGA. From September 2005 to August 2007, 12 patients underwent Tc-99m ECD brain perfusion SPECT for neuroimaging of TGA. All patients also underwent MRI and MRA including DWI (MRI). Among them, 10 patients who could be chased more than 6 months were included in this study. Their average age was 60.74.0 yrs (M: F = 2: 8) and the average duration of amnesia was 4.42.2 hrs (1 hr ∼ 7 hrs). Duration from episode of amnesia to SPECT was 4.32.4 days (1∼9 days). Precipitating factors could be identified in 6 patients: emotional stress 3, hair dyeing 1, taking a nap 1 and angioplasty 1. SPECT and MRI was visually assessed, No cerebral perfusion defect was observed on SPECT in 3 patients and their clinical outcome was all good. Among 7 patients who had cerebral perfusion defects on SPECT, 3 patients had good clinical outcome, while others did not: one had hypercholesterolemia, another had depression, and 2 patients with cerebral perfusion defects at both temporoparetal cortex was later diagnosed as early Alzheimer's disease (AD) and mild cognitive impairment (MCI). MRI was negative in 6 patients and 3 of them had excellent clinical outcome while other 3 were diagnosed as hypercholesterolemia, early AD and MCI. Among 4 patients with positive MRI, 3 showed good clinical outcome and their MRI showed lesions at medial temporal cortex and/or vertebral artery. One patient with microcalcification at left putamen was diagnosed to have depression. Large cerebral perfusion defects on SPECT may herald psychiatric or neurodegenerative diseases of transient global amnesia patients which usually shows negative MRI

  19. Glioma Grading and Determination of IDH Mutation Status and ATRX loss by DCE and ASL Perfusion.

    Science.gov (United States)

    Brendle, Cornelia; Hempel, Johann-Martin; Schittenhelm, Jens; Skardelly, Marco; Tabatabai, Ghazaleh; Bender, Benjamin; Ernemann, Ulrike; Klose, Uwe

    2017-05-09

    To evaluate arterial spin labeling (ASL) perfusion and dynamic contrast-enhanced (DCE) perfusion in glioma grading according to the previous WHO classification of 2007, as well as concerning isocitrate dehydrogenase (IDH) mutation status and ATRX expression as required by the new WHO 2016 brain tumor classification. The mean values of Ktrans, Kep, Ve, and Vp by DCE perfusion, and cerebral blood flow (CBF) by ASL perfusion were assessed retrospectively in 40 patients with initial glioma diagnosis. Perfusion parameters were correlated and compared concerning glioma grading, IDH mutation status and ATRX expression. The DCE and ASL perfusion parameters showed merely moderate correlation. The Ktrans, Ve, and CBF by DCE perfusion were different in low-grade and high-grade gliomas (p = 0.0018, p IDH mutation (p = 0.014, sensitivity = 0.75, specificity = 0.88) and showed a trend for the discrimination of astrocytomas with IDH mutation from oligodendrogliomas (p = 0.074). In conclusion, DCE and ASL perfusion are complementary in the differentiation of gliomas. The discrimination of low- and high-grade gliomas is possible by the DCE perfusion parameter Ve, while ASL perfusion shows potential for the differentiation of the IDH and ATRX mutation status of gliomas following the new WHO classification 2016. Both perfusion techniques might represent different aspects of brain tumor perfusion.

  20. Perfusion CT in childhood stroke—Initial observations and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Zebedin, D., E-mail: doris.zebedin@medunigraz.at [Division of Pediatric Radiology, Department of Radiology, University Hospital LKH Graz (Austria); Sorantin, E.; Riccabona, M. [Division of Pediatric Radiology, Department of Radiology, University Hospital LKH Graz (Austria)

    2013-07-15

    Introduction: To report the preliminary results of contrast-enhanced perfusion multi-detector CT for diagnoses of perfusion disturbances in children with clinical suspicion of stroke. Patients and methods: Within the last two years emergency perfusion CT was performed in ten children (age: 8–17 years, male:female = 3:7) for assessment of suspected childhood stroke. These intracranial perfusion CT, intracranial CT-digital subtraction angiography (CT-DSA) and extracranial CT-angiography (CTA) studies were retrospectively reviewed and compared with MRI, follow-up CT, catheter angiography and final clinical diagnosis. The total dose length product (DLP) for the entire examination was recorded. The image quality of perfusion CT-maps, CT-DSA and CTA were evaluated with a subjective three-point scale ranging from very good to non-diagnostic image quality rating perfusion disturbance, intracranial peripheral vessel depiction, and motion- or streak artifacts. Results: In nine of ten children perfusion CT showed no false positive or false negative results. In one of ten children suffering from migraine focal hypo-perfusion was read as perfusion impairment potentially indicating early stroke, but MRI and MRA follow-up were negative. Overall, perfusion-CT with CT-DSA was rated very good in 80% of cases for the detection of perfusion disturbances and vessel anatomy. Conclusions: In comparison to standard CT, contrast-enhanced perfusion CT improves CTs’ diagnostic capability in the emergency examination of children with a strong suspicion of ischemic cerebral infarction.

  1. Quantification of MRI measured myocardial perfusion reserve in healthy humans: A comparison with positron emission tomography

    DEFF Research Database (Denmark)

    Fritz-Hansen, T.; Hove, J.D.; Kofoed, K.F.

    2008-01-01

    Purpose: To validate a noninvasive quantitative MRI technique, the K-i perfusion method, for myocardial perfusion in humans using N-13-ammonia PET as a reference method. Materials and Methods: Ten healthy males (64 +/- 8 years) were examined with combined PET and MRI perfusion imaging at rest and...

  2. Unsupervised motion-compensation of multi-slice cardiac perfusion MRI

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Ólafsdóttir, Hildur; Larsson, Henrik B. W.

    2005-01-01

    is verified and stabilised using perfusion specific prior models of pose and shape estimated from training data. Qualitative and quantitative validation of the method is carried out using 2000 clinical quality, short-axis, perfusion MR slice images, acquired from ten freely breathing patients with acute...... holds great promise for the automation of cardiac perfusion investigations, due to its accuracy, robustness and generalisation ability....

  3. Validation of myocardial perfusion quantification by dynamic CT in an ex-vivo porcine heart model

    NARCIS (Netherlands)

    Pelgrim, Gert Jan; Das, Marco; van Tuijl, Sjoerd; van Assen, Marly; Prinzen, Frits W; Stijnen, Marco; Oudkerk, Matthijs; Wildberger, Joachim E; Vliegenthart, Rozemarijn

    2017-01-01

    To test the accuracy of quantification of myocardial perfusion imaging (MPI) using computed tomography (CT) in ex-vivo porcine models. Five isolated porcine hearts were perfused according to Langendorff. Hearts were perfused using retrograde flow through the aorta and blood flow, blood pressure and

  4. MYOCARDIAL PROTECTION DURING CORONARY ANGIOPLASTY WITH AUTOPERFUSION AND FORCED PERFUSION - AN IN-VITRO COMPARISON

    NARCIS (Netherlands)

    DEMUINCK, ED; VERKERKE, BJ; RAKHORST, G; LIE, KI

    During coronary angioplasty, perfusion distal to the inflated angioplasty balloon can be maintained with autoperfusion balloon catheters and coronary perfusion pumps. The blood flow rates through the autoperfusion balloon catheters and the flow rates achieved with a perfusion pump were compared in

  5. Role of perfusion SPECT in prediction and measurement of pulmonary complications after radiotherapy for lung cancer

    DEFF Research Database (Denmark)

    Farr, Katherina P; Kramer, Stine; Khalil, Azza A

    2015-01-01

    PURPOSE: The purpose of the study was to evaluate the ability of baseline perfusion defect score (DS) on SPECT to predict the development of severe symptomatic radiation pneumonitis (RP) and to evaluate changes in perfusion on SPECT as a method of lung perfusion function assessment after curative...

  6. A 4D CT digital phantom of an individual human brain for perfusion analysis

    NARCIS (Netherlands)

    Manniesing, Rashindra; Brune, Christoph; van Ginneken, Bram; Prokop, Mathias

    2016-01-01

    Brain perfusion is of key importance to assess brain function. Modern CT scanners can acquire perfusion maps of the cerebral parenchyma in vivo at submillimeter resolution. These perfusion maps give insights into the hemodynamics of the cerebral parenchyma and are critical for example for treatment

  7. Assessment of the perfusion of glioblastomas before and during radiotherapy: longitudinal comparison between H{sub 2}-{sup 15}O positron emission tomography and perfusion MRI; Evaluation de la perfusion des glioblastomes en avant et pendant la radiotherapie: comparaison longitudinale entre la tomographie par emission de positons H2 15O et l'IRM de perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Laprie, A.; Ken, S.; Moyal Cohen-Jonathan, E. [Departement de radiotherapie, institut Claudius-Regaud, 31 - Toulouse (France); Laprie, A.; Ken, S.; Lotterie, J.A.; Franceries, X.; Celsis, P.; Payoux, P.; Berry, I. [Inserm imagerie cerebrale et handicaps neurologiques UMR 825, 31 - Toulouse (France); Lotterie, J.A.; Berry, I. [Departement de biophysique, centre hospitalier universitaire de Rangueil, 31 - Toulouse (France); Barcelo, C. [Departement de radiologie, centre hospitalier universitaire de Purpan, 31 - Toulouse (France)

    2010-10-15

    The authors report the comparison of different perfusion imagery modalities for patients suffering form glioblastomas and included in a phase-1 clinic trial comprising conformational radiotherapy concomitant with the use of a farnesyl-transferase inhibitor (tipifarnib). With these different techniques, perfusion MRI and perfusion positron emission tomography, the authors made respectively a qualitative and quantitative assessment of the tumour vascularisation. Short communication

  8. How to Perfuse: Concepts of Cerebral Protection during Arch Replacement

    Directory of Open Access Journals (Sweden)

    Andreas Habertheuer

    2015-01-01

    Full Text Available Arch surgery remains undoubtedly among the most technically and strategically challenging endeavors in cardiovascular surgery. Surgical interventions of thoracic aneurysms involving the aortic arch require complete circulatory arrest in deep hypothermia (DHCA or elaborate cerebral perfusion strategies with varying degrees of hypothermia to achieve satisfactory protection of the brain from ischemic insults, that is, unilateral/bilateral antegrade cerebral perfusion (ACP and retrograde cerebral perfusion (RCP. Despite sophisticated and increasingly individualized surgical approaches for complex aortic pathologies, there remains a lack of consensus regarding the optimal method of cerebral protection and circulatory management during the time of arch exclusion. Many recent studies argue in favor of ACP with various degrees of hypothermic arrest during arch reconstruction and its advantages have been widely demonstrated. In fact ACP with more moderate degrees of hypothermia represents a paradigm shift in the cardiac surgery community and is widely adopted as an emergent strategy; however, many centers continue to report good results using other perfusion strategies. Amidst this important discussion we review currently available surgical strategies of cerebral protection management and compare the results of recent European multicenter and single-center data.

  9. Disposition kinetics of diclofenac in the dual perfused rat liver.

    Science.gov (United States)

    Sahin, Selma; Rowland, Malcolm

    2013-09-01

    This study investigates the hepatic disposition of diclofenac as a function of route of input: portal vein (PV) versus hepatic artery (HA) in the presence of its binding protein, albumin. The in situ dual perfused rat liver was performed using Krebs bicarbonate buffer containing human serum albumin (HSA, 0.25%-1%) at constant PV (12 mL/min) and HA (3 mL/min) flow rates. Bolus doses of [(14) C]-diclofenac and (125) I-labeled HSA were injected randomly into the HA or PV and then, after an appropriate interval, into the alternate vessel. Regardless of route of input and perfusion medium protein concentration, the hepatic outflow profile of diclofenac displayed a characteristic sharp peak followed by a slower eluting tail, indicating that its radial distribution is not instantaneous. Based on the estimated effective permeability-surface area product/blood flow ratio, hepatic uptake of diclofenac is governed by both perfusion and permeability. Fractional effluent recovery (F) increased as unbound diclofenac fraction in the perfusate decreased. Although no significant difference in hepatic clearance of diclofenac as a function of route of delivery at 0.5% and 1% HSA, it was demonstrable at 0.25% HSA (p < 0.001), when the extraction ratio is higher. Copyright © 2013 Wiley Periodicals, Inc.

  10. Laser Doppler perfusion monitoring and imaging: novel approaches

    NARCIS (Netherlands)

    Humeau, Anne; Steenbergen, Wiendelt; Nilsson, Henrik; Strömberg, Tomas

    2007-01-01

    Laser Doppler flowmetry (LDF) is a non invasive method enabling the monitoring of microvascular blood flow, a very important marker of tissue health. This article gives an overview on the concept of LDF for microvascular perfusion monitoring and imaging. It first describes the theoretical background

  11. Degradation of bradykinin by isolated perfused rat lung

    International Nuclear Information System (INIS)

    Churchill, M.; Orawski, A.T.; AchutaMurthy, P.N.; Simmons, W.H.

    1986-01-01

    Several studies have suggested that the essentially complete degradation of circulating bradykinin (BK) in lung is mediated in part by peptidase(s) other than the well-characterized angiotensin converting enzyme (ACE). The authors report here that the isolated perfused rat lung can inactivate BK by sequential N-terminal cleavage. [ 3 H-2, 3-Pro] BK was perfused through the lung and the products in the perfusate identified by HPLC. In the absence of inhibitors, BK was 89-100% degraded with 3 H-Pro 2 -Pro 3 and 3 H-Pro as the major products. The dipeptidylaminopeptidase IV (DAP IV) inhibitor, diprotein A (Ile-Pro-Ile), greatly reduced the Pro-Pro and Pro peaks and produced a prominent BK/sub 2-7/ peak (or BK/sub 2-9/ peak if the ACE inhibitor, captopril, was also present). 2-Mercapto-ethanol, a rather specific inhibitor of aminopeptidase P (AP-P), prevented the release of Arg 1 , producing major BK and/or BK/sub 1-7/ peaks. The neutral metalloendopeptidase inhibitor, phosphoramidon, had no effect on the pattern of degradation of BK by the perfused rat lung by the release of Arg 1 by AP-P followed by release of Pro 2 -Pro 3 by DAP IV

  12. Simultaneous Multiagent Hyperpolarized 13C Perfusion Imaging

    DEFF Research Database (Denmark)

    von Morze, Cornelius; Bok, Robert A.; Reed, Galen D.

    2014-01-01

    Purpose: To demonstrate simultaneous hyperpolarization and imaging of three 13C-labeled perfusion MRI contrast agents with dissimilar molecular structures ([13C]urea, [13C]hydroxymethyl cyclopropane, and [13C]t-butanol) and correspondingly variable chemical shifts and physiological characteristic...

  13. Hyperoxia and glutathione depletion in the isolated perfused rat liver.

    Science.gov (United States)

    Shattuck, K E; Grinnell, C D; Keeney, S E; Noworyta, K; Rassin, D K

    1997-12-01

    Hepatic stores of glutathione may be depleted by hyperoxic exposure or poor nutritional status. We studied the effects of hyperoxia or hepatic glutathione depletion on bile flow rates, and on biliary concentrations of glutathione and amino acids. Glutathione depletion was induced in vivo by 1) hyperoxic exposure (O2) for 48 hours, 2) inhibition of glutathione synthesis by treatment with buthionine sulfoximine (BSO), 3) a combination of BSO + O2, or 4) inhibition of cysteine synthesis by propargyglycine (PPG). Livers were then isolated and perfused. Glutathione concentrations in bile, liver, and perfusate were significantly decreased by all treatments. Bile flow was significantly decreased in groups treated with BSO or O2 + BSO, and perfusate LDH was increased by O2 + BSO or PPG. Significant changes in biliary amino acid concentrations included decreased sulfur-containing amino acids and increased branched-chain amino acids in groups treated with BSO, PPG, or O2; and increased essential amino acids in groups treated with O2 or PPG. Oxygen exposure or inhibition of glutathione synthesis results in significant decreases in hepatic, perfusate and biliary glutathione concentrations, and increases in biliary amino acids. A decrease in bile flow rate was associated only with the most severe glutathione depletion.

  14. [Portal perfusion with right gastroepiploic vein flow in liver transplant].

    Science.gov (United States)

    Mendoza-Sánchez, Federico; Javier-Haro, Francisco; Mendoza-Medina, Diego Federico; González-Ojeda, Alejandro; Cortés-Lares, José Antonio; Fuentes-Orozco, Clotilde

    Liver transplantation in patients with liver cirrhosis, portal vein thrombosis, and cavernous transformation of the portal vein, is a complex procedure with high possibility of liver graft dysfunction. It is performed in 2-19% of all liver transplants, and has a significantly high mortality rate in the post-operative period. Other procedures to maintain portal perfusion have been described, however there are no reports of liver graft perfusion using right gastroepiploic vein. A 20 year-old female diagnosed with cryptogenic cirrhosis, with a Child-Pugh score of 7 points (class "B"), and MELD score of 14 points, with thrombosis and cavernous transformation of the portal vein, severe portal hypertension, splenomegaly, a history of upper gastrointestinal bleeding due to oesophageal varices, and left renal agenesis. The preoperative evaluation for liver transplantation was completed, and the right gastroepiploic vein of 1-cm diameter was observed draining to the infrahepatic inferior vena cava and right suprarenal vein. An orthotopic liver transplantation was performed from a non-living donor (deceased on January 30, 2005) using the Piggy-Back technique. Portal vein perfusion was maintained using the right gastroepiploic vein, and the outcome was satisfactory. The patient was discharged 13 days after surgery. Liver transplantation was performed satisfactorily, obtaining an acceptable outcome. In this case, the portal perfusion had adequate blood flow through the right gastroepiploic vein. Copyright © 2015 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  15. Automatic quantitative analysis of cardiac MR perfusion images

    NARCIS (Netherlands)

    Breeuwer, Marcel; Spreeuwers, Lieuwe Jan; Quist, Marcel

    2001-01-01

    Magnetic Resonance Imaging (MRI) is a powerful technique for imaging cardiovascular diseases. The introduction of cardiovascular MRI into clinical practice is however hampered by the lack of efficient and accurate image analysis methods. This paper focuses on the evaluation of blood perfusion in the

  16. Effect of Garlic on Perfusion Scintigraphy of Rabbit's Lungs ...

    African Journals Online (AJOL)

    Purpose: To study of the effect of garlic on rabbit's lungs, with the aid of perfusion scintigraphy, after experimentally-induced pulmonary embolism. Methods: Twelve adult rabbits were anesthetized. Prepared macroaggregated albumin- technetium 99m (99mTc-MAA) radiopharmaceutical was injected into the ear vein at a ...

  17. Myocardial perfusion or multi cuts CT: When and how?

    International Nuclear Information System (INIS)

    Grossman, G.

    2015-01-01

    Multi Slice CT: in patients with intermediate probability mainly to exclude coronary artery disease (acute chest pain), Myocardial perfusion in patients with intermediate probability of coronary disease. To exclude and confirm ischemia and definition of conduct. There is no definition of superiority between strategies

  18. Skeletal muscle perfusion measured by positron emission tomography during exercise

    NARCIS (Netherlands)

    Ament, W; Lubbers, J; Rakhorst, G; Vaalburg, W; Verkerke, GJ; Paans, AMJ; Willemsen, ATM

    1998-01-01

    The applicability of (H2O)-O-15-positron emission tomographic (PET) imaging for the assessment of skeletal muscle perfusion during exercise was investigated in five healthy subjects performing intermittent isometric contractions on a calf ergometer. The workload of the left calf muscles was kept

  19. Counting the mismatches - lung ventilation/perfusion subtraction index

    International Nuclear Information System (INIS)

    Anderson, T.C.; Evans, S.G.; Larcos, G.; Farlow, D.C.

    1998-01-01

    Full text: There is potential for interobserver variability in interpretation of ventilation/perfusion (V/Q) scans. Objective quantification of V/Q mismatch could be useful. Thus, the aim of this study is to determine the validity of image subtraction in a group of 27 patients (11 men, 8 women; mean age 59.4 years [range 21-81 years])investigated by V/Q scans for suspected pulmonary emboli. A standard 6 view V/Q scan was obtained with two cobalt markers used on the anterior and posterior surfaces for image alignment. Ventilation images were normalised to the perfusion using an area of normal ventilation and perfusion. With the use of automated, and if required, manual alignment, perfusion images were subtracted from ventilation, with a median filter applied. A summed index of mismatch for each lung scan was calculated from the difference. This index was then retrospectively compared to the result reported by one of four experienced physicians. Two patients with chronic obstructive airways disease were excluded from analysis. We conclude that high probability V/Q scans can be differentiated from low probability studies using this index; further prospective investigation in a larger cohort is warranted

  20. Isolated limb perfusion electrochemotherapy for the treatment of an ...

    African Journals Online (AJOL)

    After completing staging procedures, the lesion was approached with surgery and intraoperative electrochemotherapy (ECT) administration of bleomycin in isolated limb perfusion. A second session of surgery and ECT was performed one month later, followed by three additional monthly sessions of ECT. During periodic ...

  1. Machine learning improves the accuracy of myocardial perfusion scintigraphy results

    International Nuclear Information System (INIS)

    Groselj, C.; Kukar, M.

    2002-01-01

    Objective: Machine learning (ML) an artificial intelligence method has in last decade proved to be an useful tool in many fields of decision making, also in some fields of medicine. By reports, its decision accuracy usually exceeds the human one. Aim: To assess applicability of ML in interpretation of the stress myocardial perfusion scintigraphy results in coronary artery disease diagnostic process. Patients and methods: The 327 patient's data of planar stress myocardial perfusion scintigraphy were reevaluated in usual way. Comparing them with the results of coronary angiography the sensitivity, specificity and accuracy of the investigation were computed. The data were digitized and the decision procedure repeated by ML program 'Naive Bayesian classifier'. As the ML is able to simultaneously manipulate with whatever number of data, all reachable disease connected data (regarding history, habitus, risk factors, stress results) were added. The sensitivity, specificity and accuracy of scintigraphy were expressed in this way. The results of both decision procedures were compared. Conclusion: Using ML method, 19 more patients out of 327 (5.8%) were correctly diagnosed by stress myocardial perfusion scintigraphy. In this way ML could be an important tool for myocardial perfusion scintigraphy decision making

  2. Evaluation of renal transplant perfusion by functional imaging

    International Nuclear Information System (INIS)

    Nicoletti, R.

    1990-01-01

    Radionuclide angiography (RNA) is used as a noninvasive method for the evaluation of renal transplant perfusion. The computer processing method generally used, based on regions of interest, is unsatisfactory because it does not permit the regional differentiation of perfusion defects. Furthermore, the subjective delineation of the regions of interest introduces considerable inter-observer variation of results. We developed a processing method which is less operator-dependent and permits the evaluation of local defects; it is based on the concept of functional imaging. The method was evaluated in 62 patient examinations, which were subdivided into four groups: Normal transplant perfusion (23 examinations), acute tubular necrose (ATN) (16), cellular rejection (13), and vascular rejection (10). Quantitative results derived from profile curves were combined with visual estimation of the functional images and yielded a synoptic graph which allowed differentiation into three groups: Normal transplant perfusion (sensitivity 0.78, specificity 0.97), ATN or cellular rejection (sens. 0.83, spec. 0.82), and vascular rejection (sens. 0.90, spec. 0.92). (orig.)

  3. Effect of Garlic on Perfusion Scintigraphy of Rabbit's Lungs ...

    African Journals Online (AJOL)

    Purpose: To study of the effect of garlic on rabbit's lungs, with the aid of perfusion scintigraphy, after experimentally-induced ... scintigraphic images of the healthy rabbits' lungs were taken, and pulmonary embolism was experimentally induced by ... and pulmonary embolism, lung ventilation scans can be performed using.

  4. desensitisation and calcium-sensitivity in the isolated perfused rat ...

    African Journals Online (AJOL)

    Dr Olaleye

    possibly by Ca2+ overload, occurs when high extracellular [Ca2+] (2.5 or 5mM) is present during activation by NA. This can be prevented ... peristaltic cassette pump, 501U with 501M multi-channel pumphead) and the perfusion pressure was recorded. This rate of ..... between Bay K 8644 and nifedipine in K+ depolarized ...

  5. Desensitisation and calcium-sensitivity in the isolated perfused rat ...

    African Journals Online (AJOL)

    -induced desensitisation to noradrenaline were studied in the isolated perfused rat tail artery. Responses to the activators noradrenaline (NA) (3μM) and potassium chloride (KCl) (100mM) were obtained in Ca2+-buffered saline. Activators ...

  6. Cell volume changes affect gluconeogenesis in the perfused liver of ...

    Indian Academy of Sciences (India)

    Unknown

    In conclusion, gluconeogenesis appears to play a vital role in C. batrachus in maintaining glucose homeostasis, which is influenced by cell volume changes possibly for proper energy supply under osmotic stress. [Goswami C, Datta S, Biswas K and Saha N 2004 Cell volume changes affect gluconeogenesis in the perfused ...

  7. Muscle perfusion and metabolic heterogeneity: insights from noninvasive imaging techniques

    DEFF Research Database (Denmark)

    Kalliokoski, Kari K; Scheede-Bergdahl, Celena; Kjaer, Michael

    2006-01-01

    Recent developments in noninvasive imaging techniques have enabled the study of local changes in perfusion and metabolism in skeletal muscle as well as patterns of heterogeneity in these variables in humans. In this review, the principles of these techniques along with some recent findings...

  8. Intracranial CT angiography obtained from a cerebral CT perfusion examination

    NARCIS (Netherlands)

    Gratama van Andel, H. A. F.; Venema, H. W.; Majoie, C. B.; den Heeten, G. J.; Grimbergen, C. A.; Streekstra, G. J.

    2009-01-01

    CT perfusion (CTP) examinations of the brain are performed increasingly for the evaluation of cerebral blood flow in patients with stroke and vasospasm after subarachnoid hemorrhage. Of the same patient often also a CT angiography (CTA) examination is performed. This study investigates the

  9. Complications of hemorrhagic and ischemic stroke : a CT perfusion evaluation

    NARCIS (Netherlands)

    Dankbaar, J.W.

    2010-01-01

    In this thesis the use of CT-perfusion (CTP) imaging in the evaluation of the most severe complications of subarachnoid hemorrhage (SAH)) and ischemic stroke was explored. These complications are delayed cerebral ischemia (DCI) after SAH and damage to the blood-brain barrier (BBB) after ischemic

  10. A comparison of flow gradients across disposable arterial perfusion cannulas.

    Science.gov (United States)

    Brodman, R; Siegel, H; Lesser, M; Frater, R

    1985-03-01

    Five-hundred members of The Society of Thoracic Surgeons were canvassed to discover which cannulas are currently used for open-heart surgical procedures in adults; 120 surgeons responded. The mean arterial line pressure produced by 29 disposable arterial perfusion cannulas (size range, 16F to 30F) at flow rates of 1 to 5 liters per minute was compared. A roller pump with perfusion tubing 95 mm (0.75 inch) in diameter was used with water as the test solution. Line pressures in these cannulas ranged from 22.4 +/- 2.30 (standard deviation) to 271.0 +/- 6.60 mm Hg at 5 L/min. Four 24F cannulas had gradients of less than 55 mm Hg at a flow rate of 5 L/min, and 6 cannulas--4 of which were 22F and 2, 24F--had gradients higher than 150 mm Hg at 5 L/min. A number of cannulas kinked easily, and these showed marked increases in line pressure. The following results were obtained from this study: (1) a wide range of line pressures was observed in disposable arterial perfusion cannulas currently in clinical use; (2) some cannulas currently used for cardiopulmonary bypass in adults generated excessive line pressure; and (3) both material and design affect function, with some designs being safer than others. Cardiac surgeons should base the choice of an arterial perfusion cannula on the best performance and safest design available to avoid cannula-related problems at operation.

  11. Development of a microfluidic perfusion 3D cell culture system

    Science.gov (United States)

    Park, D. H.; Jeon, H. J.; Kim, M. J.; Nguyen, X. D.; Morten, K.; Go, J. S.

    2018-04-01

    Recently, 3-dimensional in vitro cell cultures have gained much attention in biomedical sciences because of the closer relevance between in vitro cell cultures and in vivo environments. This paper presents a microfluidic perfusion 3D cell culture system with consistent control of long-term culture conditions to mimic an in vivo microenvironment. It consists of two sudden expansion reservoirs to trap incoming air bubbles, gradient generators to provide a linear concentration, and microchannel mixers. Specifically, the air bubbles disturb a flow in the microfluidic channel resulting in the instability of the perfusion cell culture conditions. For long-term stable operation, the sudden expansion reservoir is designed to trap air bubbles by using buoyancy before they enter the culture system. The performance of the developed microfluidic perfusion 3D cell culture system was examined experimentally and compared with analytical results. Finally, it was applied to test the cytotoxicity of cells infected with Ewing’s sarcoma. Cell death was observed for different concentrations of H2O2. For future work, the developed microfluidic perfusion 3D cell culture system can be used to examine the behavior of cells treated with various drugs and concentrations for high-throughput drug screening.

  12. A evidenciação dos fatos contábeis ambientais como forma de cumprimento com as obrigações relativas ao meio ambiente

    OpenAIRE

    Sager, André

    2011-01-01

    Artigo apresentado à Fundação Universidade Federal de Rondônia – UNIR, Campus de Cacoal, como requisito parcial para obtenção do grau de Bacharel em Ciências Contábeis, sob orientação da Profª. Ma. Estela Pitwak Rossoni. Diante das obrigações contábeis da empresa em relação ao meio ambiental, este trabalho, tem por objetivo, verificar a percepção e posicionamento dos contadores, quanto à evidenciação dos fatos ambientais nas demonstrações contábeis. Para tanto, foi realizada pesquisa bibli...

  13. Dynamic (4D) CT perfusion offers simultaneous functional and anatomical insights into pulmonary embolism resolution

    Energy Technology Data Exchange (ETDEWEB)

    Mirsadraee, Saeed, E-mail: saeed.mirsadraee@ed.ac.uk [Clinical Research Imaging Centre, Queen' s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ (United Kingdom); Reid, John H.; Connell, Martin [Clinical Research Imaging Centre, Queen' s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ (United Kingdom); MacNee, William; Hirani, Nikhil [The Queen' s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ (United Kingdom); Murchison, John T. [Department of Radiology, Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA (United Kingdom); Beek, Edwin J. van [Clinical Research Imaging Centre, Queen' s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ (United Kingdom)

    2016-10-15

    Objective: Resolution and long-term functional effects of pulmonary emboli are unpredictable. This study was carried out to assess persisting vascular bed perfusion abnormalities and resolution of arterial thrombus in patients with recent pulmonary embolism (PE). Methods and materials: 26 Patients were prospectively evaluated by dynamic (4D) contrast enhanced CT perfusion dynamic pulmonary CT perfusion. Intermittent volume imaging was performed every 1.5–1.7 s during breath-hold and perfusion values were calculated by maximum-slope technique. Thrombus load (modified Miller score; MMS) and ventricular diameter were determined. Perfusion maps were visually scored and correlated with residual endoluminal filling defects. Results: The mean initial thrombus load was 13.1 ± 4.6 MMS (3–16), and 1.2 ± 2.1 MMS (0–8) at follow up. From the 24 CTPs with diagnostic quality perfusion studies, normal perfusion was observed in 7 (29%), and mildly-severely abnormal in 17 (71%). In 15 patients with no residual thrombus on follow up CTPA, normal perfusion was observed in 6, and abnormal perfusion in 9. Perfusion was abnormal in all patients with residual thrombus on follow up CTPA. Pulmonary perfusion changes were classified as reduced (n = 4), delayed (systemic circulation pattern; n = 5), and absent (no-flow; n = 5). The right ventricle was dilated in 12/25 (48%) at presentation, and normal in all 26 follow up scans. Weak correlation was found between initial ventricular dilatation and perfusion abnormality at follow up (r = 0.15). Conclusions: Most patients had substantial perfusion abnormality at 3–6 months post PE. Abnormal perfusion patterns were frequently observed in patients and in regions with no corresponding evidence of residual thrombus on CTPA. Some defects exhibit delayed, presumed systemic, enhancement (which we have termed ‘stunned’ lung). CT perfusion provides combined anatomical and functional information about PE resolution.

  14. Importance of multidetector CT imaging in multiple trauma; Stellenwert der Multidetektor-CT bei Polytrauma

    Energy Technology Data Exchange (ETDEWEB)

    Linsenmaier, U. [HELIOS Kliniken Muenchen West, HELIOS Klinik Muenchen Perlach, Institut fuer Diagnostische und Interventionelle Radiologie, Muenchen (Germany); Geyer, L.L.; Reiser, M.; Wirth, S. [Klinikum der Ludwig-Maximilians-Universitaet, Institut fuer Klinische Radiologie, Muenchen (Germany); Koerner, M. [Radiologie Muehleninsel, Landshut (Germany)

    2014-09-15

    zeitnahe Therapie mit dem Ziel, potenziell lebensbedrohliche Verletzungen fruehzeitig zu erkennen und adaequat zu behandeln. Die Basisdiagnostik triagiert zur Sofortoperation und besteht unveraendert aus einer fokussierten Ultraschalluntersuchung (Focused Assessment with Sonography for Trauma, FAST) und Projektionsradiographie (CR), meist limitiert auf eine einzelne Thoraxaufnahme. Die Multidetektor-CT (MDCT) hat sich als standardisierte fruehe Ganzkoerper-CT (''whole-body'', WBCT) etabliert; die Detektionsrate von Verletzungen ist herausragend und die Ueberlebenswahrscheinlichkeit verbessert sich um 20-25 %. Die raeumliche und zeitliche Aufloesung wurde verbessert und die Untersuchungszeit erheblich verkuerzt. Die Dosisexposition ist auch bei einmaliger Akutanwendung nicht unerheblich, durch moderne Scannertechnologie und Dosisreduktion, einschliesslich der iterativen Bildrekonstruktion, konnte eine Dosisreduktion von bis zu 40 % erreicht werden. Die zahlreichen Bilder der WBCT muessen prioritaetenorientiert hergestellt, befundet und archiviert werden, zur schnellen Diagnostik bietet sich das ''volume image reading'' (VIR) an. Die moderne WBCT wir bei Polytrauma frueh, umfassend und individuell adaptiert durchgefuehrt, dabei verbessert die WBCT die Ueberlebenswahrscheinlichkeit um 20-25 %. (orig.)

  15. MUDANÇAS OCASIONADAS PELOS SISTEMAS DE INFORMAÇÕES CONTÁBEIS EM ESCRITÓRIOS DE CONTABILIDADE

    Directory of Open Access Journals (Sweden)

    Vania Regina Morás

    2015-06-01

    Full Text Available O presente estudo teve como objetivo analisar as mudanças ocasionadas pelos sistemas de informações contábeis nos escritórios de contabilidade, abordando a teoria da contingência como processo para intermediar as contingências internas e externas em relação aos sistemas de informações contábeis. Trata-se de uma pesquisa descritiva com abordagem qualitativa, realizada por meio de entrevistas em três escritórios de contabilidade. Como resultados encontrados, destacam-se, com relação ao contexto organizacional, observou-se, que as três empresas trabalham com as informações de outputs integradas dentro de seus sistemas de informações, porém as informações de inputs. Com relação à estrutura organizacional, A empresa A se destacou ainda com a preocupação demonstrada para com seus sistemas de informação. Com relação ao contexto interorganizacional, os três escritórios demonstraram que, além de terem um colaborador responsável pelo departamento de tecnologia da informação (T.I., também investem na contratação de empresas terceirizadas objetivando contribuir para melhoras em seus sistemas de informações contábeis, de acordo com suas necessidades. Como conclusões do estudo pode-se apontar que os três escritórios se preocupam com seus sistemas de informações, mas o destaque principal foi a empresa A, que tem uma preocupação muito maior em relação as outras duas.

  16. BeiDou and Galileo, Two Global Satellite Navigation Systems in Final Phase of the Construction, Visibility and Geometry

    Directory of Open Access Journals (Sweden)

    Jacek Januszewski

    2016-09-01

    Full Text Available Spatial segment is one of three segments of each satellite navigation systems (SNS. Nowadays two SNSs, GPS and GLONASS, are fully operational, two next SNSs, BeiDou in China and Galileo in Europe, are in final phase of the construction. In the case of China system this segment will consist of 35 satellites with three types of orbits ? medium (MEO, geostationary (GEO and inclined geosynchronous (IGSO. As GEO and IGSO satellites can be used in China and Asia-Pacific region only, BeiDou MEO constellation with 27 fully operational satellites will be taken into account in this paper. The orbital planes of the Galileo constellation will be divided in “slots” that contains at least one operational satellite. The Galileo reference constellation has 24 nominal orbital positions or operational slots in MEO homogeneously distributed in 3 orbital planes; i.e. 8 slots equally spaced per plane. As the error of user’s position obtained from both systems depends on geometry factor DOP (Dilution Of Precision among other things the knowledge of the number of satellites visible by the user above given masking elevation angle Hmin and the distributions of DOP coefficient values, GDOP in particular, is very important. The lowest and the greatest number of satellites visible in open area by the observer at different latitudes for different Hmin, the percentage of satellites visible above angle H, distributions (in per cent of satellites azimuths and GDOP coefficient values for different Hmin for BeiDou and Galileo systems at different latitudes are presented in the paper.

  17. 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.)

  18. Gerenciamento de Resultados Contábeis por meio de Ativos Fiscais Diferidos

    Directory of Open Access Journals (Sweden)

    Valdiney Alves de Oliveira

    2009-03-01

    Full Text Available O desenvolvimento das organizações, do mercado de capitais e a necessidade de geração de riqueza e maximização de valor para os acionistas tornam a transparência dos atos dos gestores em relação às empresas crucial na condução dos negócios e no processo de controle e tomada de decisão, possibilitando, assim, maior atratividade para o capital necessário aos projetos das empresas. Como resposta ao estímulo do mercado de capitais, surge, então, a possibilidade de gerenciamento de resultados. A proposta deste trabalho consiste em analisar essa hipótese, por meio do ativo fiscal diferido e fundamentar discussões sobre a relevância do tema gerenciamento de resultados contábeis e suas implicações nas empresas brasileiras. O ativo fiscal diferido foi instituído pelo pronunciamento do Instituto dos Auditores Independentes do Brasil (IBRACON e aprovado pela Comissão de Valores Mobiliários (CVM por meio da Deliberação no 273/98. A metodologia utilizada consiste de uma pesquisa descritiva documental, realizada por meio de um estudo de caso comparativo dos resultados e dos ativos fiscais diferidos das quatro maiores empresas de telecomunicações do mercado brasileiro, no período de 2003 a 2007. Como resultado, verifica-se a adoção da prática do diferimento de ativos fiscais nas demonstrações das empresas analisadas.

  19. Aspectos Contábeis dos Créditos de Carbono: Estudo com Autores Nacionais

    Directory of Open Access Journals (Sweden)

    Vanderlei dos Santos

    2013-12-01

    Full Text Available O estudo objetiva verificar o entendimento de autores nacionais no que concerne à classificação, forma de reconhecimento e mensuração das operações com créditos de carbono. O estudo de natureza descritiva foi realizado em 2011, por meio de pesquisa de levantamento ou survey, com abordagem quantitativa. Utilizou-se o questionário como instrumento de coleta de dados, que foi enviado a 23 pesquisadores nacionais que possuem publicação de artigos relacionados à contabilização dos créditos de carbono em periódicos nacionais. Obtiveram-se nove respostas, que constituíram numa amostra por acessibilidade. Para a análise dos dados obtidos optou-se pelo uso da técnica da entropia informacional. Os resultados do estudo mostraram que, quanto à classificação dos créditos de carbono, há um entendimento maior entre os autores de que se trata de ativos especiais e que não podem ser considerados como commodity. Observou-se que não há consenso entre os autores em classificar os créditos de carbono como ativo intangível ou estoque. Deste modo, concluiu-se que ainda existem divergências no entendimento dos autores analisados no que concerne aos aspectos contábeis das operações com créditos de carbono. O artigo contribui principalmente na medida em que busca consolidar diferentes opiniões de autores, que pesquisam sobre a temática, demonstrando aspectos convergentes e divergentes, além de enfatizar lacunas para desenvolver pesquisas futuras.

  20. Fetal magnetic resonance imaging. Diagnostics in congenital diaphragmatic hernia; Fetale Magnetresonanztomographie. Diagnostik bei kongenitaler Zwerchfellhernie

    Energy Technology Data Exchange (ETDEWEB)

    Kilian, A.K.; Buesing, K.A.; Neff, K.W. [Fakultaet fuer Klinische Medizin der Universitaet Heidelberg, Institut fuer Klinische Radiologie, Universitaetsklinikum Mannheim (Germany); Schaible, T. [Fakultaet fuer Klinische Medizin der Universitaet Heidelberg, Kinderklinik, Universitaetsklinikum Mannheim (Germany)

    2006-02-15

    Ultrasonography is the primary imaging modality for the evaluation of fetal or maternal anomalies. This method is safe, relatively inexpensive, easily accessible, and allows real-time imaging. Continuous technical improvements in ultrasonography in the last 10-15 years have led to improved diagnostic accuracy for fetal malformations. In cases of complex anomalies magnetic resonance imaging (MRI) can provide additional information. MRI has evolved as a valuable diagnostic method for evaluating fetal pathology. Particularly with regard to similarity of liver and lung parenchyma in ultrasonography, diagnosis of congenital diaphragmatic hernia (CDH) can be difficult. Beside morphological aspects, e.g., herniation of abdominal contents into the chest, small amounts of compressed lung can be visualized on MRI. The feasibility of using volumetric measurement on MRI may be helpful to predict high-risk fetuses and facilitate decisions to assure adequate prenatal and postnatal management to improve postnatal outcome. (orig.) [German] Der Ultraschall dient in der Schwangerschaft routinemaessig als Screeningmethode fuer fetale und maternale Anomalien, da dieser als sicher fuer Kind und Mutter, guenstig, allseits verfuegbar gilt und die Moeglichkeit einer Real-time-Darstellung bietet. Insbesondere aufgrund der Weiterentwicklung in den letzten 10-15 Jahren verfuegt der Ultraschall ueber eine hohe Aussagekraft bzgl. fetaler Fehlbildungen. In einzelnen Faellen, z. B. bei komplexen Fehlbildungen, kann die Magnetresonanztomographie (MRT) suffiziente Zusatzinformationen liefern. Aus diesem Grund hat sich die fetale MRT zur Diagnostik fetaler Fehlbildungen bewaehrt. Die Diagnose einer kongenitalen Zwerchfellhernie (congenital diaphragmatic hernia, CDH) kann im Ultraschall gerade durch sonographische Aehnlichkeit von Leber und Lunge erschwert sein. Im Falle einer CDH bietet die MRT neben der reinen Morphologie, u. a. der Ausdehnung der nach intrathorakal hernierten Abdominalorgane, die

  1. Neue radiologische und serologische Methoden zur Diagnose der renalen Osteodystrophie bei Dialysepatienten

    Directory of Open Access Journals (Sweden)

    Cejka D

    2014-01-01

    Full Text Available Mit Abnahme der Nierenfunktion steigt die Prävalenz der renalen Osteodystrophie (ROD, im Dialysestadium ist fast jeder Patient von ROD betroffen. Dialysepatienten haben verglichen mit der Normalbevölkerung ein 4-fach erhöhtes Risiko, eine Oberschenkelhalsfraktur zu erleiden. Die ROD ist eine Urämie-bedingte Erkrankung des Knochens, die zu Veränderungen des Knochenstoffwechsels („turnover“ [T], der Mineralisierung („mineralization“ [M] und des Knochenvolumens („volume“ [V] führen kann. Bislang ist die Untersuchung all dieser Veränderungen nur mittels invasiver Knochenbiopsie mit anschließender Histomorphometrie und TMV-Klassifizierung möglich. Klinisch verfügbare Methoden wie Knochendichtemessung („dual-energy X-ray absorptiometry“ [DXA] oder Bestimmung von Parathormon beziehungsweise von Knochenstoffwechselparametern zeigen niedrige Sensitivitäten/Spezifitäten bezüglich der korrekten Klassifizierung der ROD. Unter den neuen radiologischen Methoden erscheint die „high-resolution peripheral quantitative computed tomography“ (HR-pQCT eine vielversprechende Methode. In einer Studie war die HR-pQCT der konventionellen DXA bezüglich der Unterscheidung zwischen Dialysepatienten mit und ohne Vorgeschichte einer Low-trauma-Fraktur deutlich überlegen. Unter den neu entdeckten Knochenstoffwechselmarkern hat die Messung von Sclerostin einen hohen Vorhersagewert für das Vorliegen einer „highturnover bone disease“ gezeigt. Diesen interessanten Ansätzen zum Trotz bedarf es weiterer Forschung auf dem Gebiet. Insbesondere gibt es bislang keine Methode, die mit hoher Sicherheit Low-impact-Frakturen bei Dialysepatienten vorhersagen kann.

  2. Transplacental pharmacokinetics of diclofenac in perfused human placenta.

    Science.gov (United States)

    Shintaku, Kyohei; Hori, Satoko; Tsujimoto, Masayuki; Nagata, Hideaki; Satoh, Shoji; Tsukimori, Kiyomi; Nakano, Hitoo; Fujii, Tomoyuki; Taketani, Yuji; Ohtani, Hisakazu; Sawada, Yasufumi

    2009-05-01

    The aims of this study were to evaluate the transplacental transfer properties of diclofenac and to determine the effect of L-lactic acid on the transplacental transfer of diclofenac. The maternal and fetal vessels of human placenta were perfused in a single-pass mode with a solution containing diclofenac and antipyrine. The transplacental pharmacokinetic model was fitted to the time profiles of the drug concentrations in the effluent and placenta to obtain transplacental pharmacokinetic parameters. In addition, chloride ion in the perfusate was partially replaced with L-lactic acid to see the change in the transplacental transfer properties of diclofenac. The TPT(ss) value (ratio of the rate of amount transferred across the placenta to that infused in the steady state) of diclofenac was 2.22%, which was approximately one-third that of antipyrine and was significantly reduced in the presence of L-lactic acid. The transplacental pharmacokinetic model could adequately explain the transplacental transfer of diclofenac with influx clearances from maternal and fetal perfusates to placental tissue of 0.276 and 0.0345 ml/min/g cotyledon and efflux rate constants from placental tissue to maternal and fetal perfusates of 0.406 and 0.0337 min(-1), respectively. By taking into account protein binding, the placental tissue/plasma concentration ratio in humans for diclofenac was estimated to be 0.108 ml/g of cotyledon and was smaller than that of antipyrine. In conclusion, human placental perfusion and transplacental pharmacokinetic modeling allowed us to determine the transplacental transfer properties of diclofenac quantitatively. Diclofenac may share transplacental transfer system(s) with L-lactic acid.

  3. Characteristics of Brain Perfusion in Patients of Parkinson's Disease

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Young Jin; Park, Min Jung; Kim, Jae Woo; Kang, Young Kang [Dong-A University College of Medicine, Busan (Korea, Republic of)

    2008-02-15

    It was well known that cerebral blood perfusion is normal or diffusely decreased in the majority of patients with Parkinson's disease (PD). Actually we interpreted brain perfusion SPECT images of PD patients in the clinical situation, we observed various cerebral perfusion patterns in patients with PD. So we performed brain perfusion SPECT to know the brain perfusion patterns of PD patients and the difference of perfusion patterns according to the sex and the age. Also we classified PD patients into small groups based on the brain perfusion pattern. Two hundred nineteen patients (M: 70, F: 149, mean age: 62.9{+-}6.9 y/o) who were diagnosed as PD without dementia clinically and 55 patients (M: 15, F: 40, mean age: 61.4{+-}9.2 y/o) as normal controls who had no past illness history were performed {sup 99m}Tc-HMPAO brain perfusion SPECT and neuropsychological test. At first, we compared all patients with PD and normal controls. Brain perfusion in left inferior frontal gyrus, left insula, left transverse temporal gyrus, left inferior parietal lobule, left superior parietal lobule, right precuneus, right caudate tail were lower in patients with PD than normal controls. Secondly, we compared male and female patients with PD and normal controls, respectively. Brain perfusion SPECT showed more decreased cerebral perfusion in left hemisphere than right side in both male and female patients compared to normal controls. And there was larger hypoperfusion area in female patients compared with male. Thirdly, we classified patients with PD and normal controls into 4 groups according to the age and compared brain perfusion respectively. In patient below fifties, brain perfusion in both occipitoparietal and left temporal lobe were lower in PD group. As the patients with PD grew older, hypoperfusion area were shown in both frontal, temporal and limbic lobes. Fourthly, We were able to divide patients into small groups based on cerebral perfusion pattern. There was normal

  4. Role of myocardial perfusion single photon emission computed tomography in pediatric cardiology practice

    Directory of Open Access Journals (Sweden)

    Sundaram P

    2009-01-01

    Full Text Available Diagnostic and prognostic power of myocardial perfusion imaging in patients with coronary artery disease has been demonstrated with planar imaging which was further improvised with addition of gated SPECT and newer Technetium labeled myocardial perfusion tracers like SestaMIBI, Tetrofosmin. Myocardial perfusion abnormalities at rest and after stress are considered to be the best predictors of cardiac event-free survival in adults with ischemic heart disease. This article highlights various myocardial perfusion imaging (MPIradiopharmaceuticals, exercise procedures, pharmacological stress protocols, indications for MPI and myocardial perfusion patterns in children with some of the common congenital and acquired heart diseases.

  5. Logfile-Analysen: Möglichkeiten und Grenzen ihrer Nutzung bei Untersuchungen zur Mensch-Maschine-Interaktion

    Directory of Open Access Journals (Sweden)

    Burkhard Priemer

    2004-06-01

    Full Text Available Die Aufzeichnung der Computernutzung in automatisch generierten elektronischen Protokollen – so genannten Logfiles – entwickelt sich zu einer zunehmend genutzten Erfassungsmethode bei Untersuchungen der Interaktion zwischen Mensch und Computer. Dieser Beitrag bietet einen einführenden Überblick über Verfahren der Logfile-Aufzeichnung und der Analyse der Daten. Neben einer Erläuterung der Begrifflichkeiten werden sowohl Vor- und Nachteile von Logfile-Auswertungen als auch grundlegende Methoden, mathematische Beschreibungen des Nutzerverhaltens und Ansätze der Typisierung von Nutzeraktivitäten dargestellt.

  6. Naturwissenschaftliche Bildung fördern Indikatoren und Zusammenhänge bei Entwicklungsprozessen in SWiSE

    CERN Document Server

    Felchlin, Irene; Labudde, Peter

    2016-01-01

    PISA und TIMSS führten zu einem vermehrten Kompetenzdiskurs in Schule, Unterricht und Bildungspolitik. SWiSE versucht kompetenzorientierten Unterricht durch die Einführung bzw. Weiterentwicklung des selbstständigen Lernens, offener Lehr-Lernformen und Lehrerkooperation zu fördern. Doch stellt sich die Frage, wie unterrichtsrelevant solche Entwicklungsversuche sind. Die Buchbeiträge widmen sich der praxistauglichen Förderung von naturwissenschaftlichem Unterricht. Sie zeigen die Bedeutung von Schule als integrierendem System für alle Beteiligten bei Entwicklungsprozessen. Anhand empirischer Daten aus der Projektevaluation ergeben sich Ansätze zur Umsetzung auf den Ebenen Schule, Lehrpersonen und Lernende.

  7. Vergleichsuntersuchung zu Kognition und Verhalten im modifizierten versus doppelten Hole-Board-Test anhand verschiedener Habituierungsprotokolle bei der Ratte

    OpenAIRE

    Hufen, Heike Sibyl

    2006-01-01

    Untersuchung des Einflusses einer Abänderung des etablierten Testsystems modifiziertes Hole-Board und der Auswirkung verschiedener Habituierungsprotokolle auf Kognition und Verhalten von Ratten in dem Verhaltenstest. Einführung eines verkürzten Habituierungsprotokolls und des neu entwickelten doppelten Hole-Board-Tests als Test für Kognition und Verhalten. Die Veränderung am Testsystem ruft bei der Ratte die Wahl einer veränderten Verhaltensstrategie hervor, die Einführung eines nur eintägige...

  8. PENGUKURAN KINERJA KEUANGAN DENGAN METODE EAGLES (Studi Kasus Pada Bank BUMN Yang Listing Di BEI Tahun 2011 - 2013

    Directory of Open Access Journals (Sweden)

    Arif Hartono

    2016-03-01

    Full Text Available Kinerja keuangan bank biasanya diukur dengan indikator kecukupan modal, likuiditas dan profitabilitas bank. Penelitian ini menggunakan analisis EAGLES, untuk mengukur dan membandingkan kinerja bank secara lebih tepat, obyektif dan konsisten. Populasi yang digunakan adalah semua bank BUMN yang listing di BEI tahun 2011-2013. Hasil penelitian diketahui bahwa kinerja keuangan bank BUMN ditinjau dari rasio ROA (Return On Asset, Asset Quality, DGR (Deposite Growth Rate, CCR (Core Capital Ratio, SRQ by Out Interest, menunjukan nilai normal. Sedangkan bank BUMN ditinjau dari aspek, ROE (Return On Equity , LGR (loan growth rate, liquidity, CAR (capital adequacy ratio SRQ by Personalia, menunjukan kinerja keuangan yang kurang baik.

  9. Effektivität verschiedener Spültechniken bei der Entfernung von Kalziumhydroxid aus dem Wurzelkanal

    OpenAIRE

    Wießner, Thomas

    2012-01-01

    1.1 Hintergrund und Ziele Eine undichte Wurzelkanalfüllung kann zur bakteriellen Reinfektion und zum Misserfolg der endodontischen Behandlung führen. Eine unvollständige Entfernung der medikamentösen Einlage trägt zur insuffizienten Randständigkeit bei und sollte aus diesem Grund vermieden werden. Es existieren verschiedene Methoden zur Reinigung von Wurzelkanälen. Ziel dieser Studie war es drei Techniken zur Entfernung von Kalziumhydroxid vergleichend zu prüfen und deren Reinigungsleistung z...

  10. 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

    Separate assessment of respiratory mechanics, gas exchange and pulmonary circulation is essential for the diagnosis and therapy of pulmonary diseases. Due to the global character of the information obtained clinical lung function tests are often not sufficiently specific in the differential diagnosis or have a limited sensitivity in the detection of early pathological changes. The standard procedures of pulmonary imaging are computed tomography (CT) for depiction of the morphology as well as perfusion/ventilation scintigraphy and single photon emission computed tomography (SPECT) for functional assessment. Magnetic resonance imaging (MRI) with hyperpolarized gases, O{sub 2}-enhanced MRI, MRI with fluorinated gases and Fourier decomposition MRI (FD-MRI) are available for assessment of pulmonary ventilation. For assessment of pulmonary perfusion dynamic contrast-enhanced MRI (DCE-MRI), arterial spin labeling (ASL) and FD-MRI can be used. Imaging provides a more precise insight into the pathophysiology of pulmonary function on a regional level. The advantages of MRI are a lack of ionizing radiation, which allows a protective acquisition of dynamic data as well as the high number of available contrasts and therefore accessible lung function parameters. Sufficient clinical data exist only for certain applications of DCE-MRI. For the other techniques, only feasibility studies and case series of different sizes are available. The clinical applicability of hyperpolarized gases is limited for technical reasons. The clinical application of the techniques described, except for DCE-MRI, should be restricted to scientific studies. (orig.) [German] Die separate Beurteilung von Atemmechanik, Gasaustauschprozessen und Lungenzirkulation ist wesentlich fuer die Diagnose und Therapie von Lungenerkrankungen. Klinische Lungenfunktionstests sind aufgrund ihrer zumeist nur globalen Aussage oft nicht hinreichend spezifisch in der Differenzialdiagnostik oder eingeschraenkt sensitiv bei der

  11. Glucagon-like peptide-1 secretion is influenced by perfusate glucose concentration and by a feedback mechanism involving somatostatin in isolated perfused porcine ileum

    DEFF Research Database (Denmark)

    Hansen, Lene; Hartmann, Bolette; Mineo, Hitoshi

    2004-01-01

    isolated perfused porcine ileum (n=17). Effluents were measured for GLP-1 and SS. Perfusion pressure and motility were recorded. Investigated parameters included spontaneous fluctuations, changes in perfusate glucose concentrations (3.5, 5, 11 mM) and addition of insulin (1 nM). We also investigated...... the effect of proglucagon products, glucagon (10 nM), GLP-1 and GLP-2 (0.1, 1, and 10 nM) on GLP-1 and SS secretion, as well as on glucagon-like peptide-2 (GLP-2), peptide YY (PYY) and GIP secretion, all possible product of L-cells or neighbour cells. Perfusate glucose concentration dose...

  12. Steady-state first-pass perfusion (SSFPP): a new approach to 3D first-pass myocardial perfusion imaging.

    Science.gov (United States)

    Giri, Shivraman; Xue, Hui; Maiseyeu, Andrei; Kroeker, Randall; Rajagopalan, Sanjay; White, Richard D; Zuehlsdorff, Sven; Raman, Subha V; Simonetti, Orlando P

    2014-01-01

    To describe and characterize a new approach to first-pass myocardial perfusion utilizing balanced steady-state free precession acquisition without the use of saturation recovery or other magnetization preparation. The balanced steady-state free precession sequence is inherently sensitive to contrast agent enhancement of the myocardium. This sensitivity can be used to advantage in first-pass myocardial perfusion imaging by eliminating the need for magnetization preparation. Bloch equation simulations, phantom experiments, and in vivo 2D imaging studies were run comparing the proposed technique with three other methods: saturation recovery spoiled gradient echo, saturation recovery steady-state free precession, and steady-state spoiled gradient echo without magnetization preparation. Additionally, an acquisition-reconstruction strategy for 3D perfusion imaging is proposed and initial experience with this approach is demonstrated in healthy subjects and one patient. Phantom experiments verified simulation results showing the sensitivity of the balanced steady-state free precession sequence to contrast agent enhancement in solid tissue is similar to that of magnetization-prepared acquisitions. Images acquired in normal volunteers showed the proposed technique provided superior signal and signal-to-noise ratio compared with all other sequences at baseline as well as postcontrast. A new approach to first-pass myocardial perfusion is presented that obviates the need for magnetization preparation and provides high signal-to-noise ratio. Copyright © 2013 Wiley Periodicals, Inc.

  13. Reflexos da Lei n.º 11.638/07 nos indicadores contábeis das empresas têxteis listadas na BM&FBovespa

    Directory of Open Access Journals (Sweden)

    Nelson Hein

    2013-06-01

    Full Text Available Em dezembro de 2007, foi promulgada no Brasil a Lei n.º 11.638 (2007, que alterou a Lei das Sociedades Anônimas. Alterações significativas foram impostas pela lei, entre elas a adoção das normas brasileiras de contabilidade em conformidade com as normas internacionais, que implica em diversas mudanças nas demonstrações contábeis. Nessa percepção de mudanças nas demonstrações contábeis, podem ocorrer também alterações nos indicadores contábeis utilizados na análise de balanços. Nesse contexto, o artigo objetiva verificar se houve reflexos estatisticamente significativos nos indicadores contábeis após a Lei n.º 11.638 (2007. Realizou-se um estudo descritivo com uma abordagem quantitativa. A coleta dos dados ocorreu por meio das Demonstrações Financeiras Padronizadas (DFPs de 2000 a 2008 disponibilizadas no sítio da Comissão de Valores Mobiliários (CVM. A amostra por acessibilidade compreendeu 16 empresas listadas na BM&FBovespa classificadas no setor de consumo cíclico, no subsetor tecidos, vestuário e calçados, segmento fios e tecidos que possuíam todas as DFPs do período de 2000 a 2008. Aplicaram-se as técnicas estatísticas de regressão linear com base no Modelo de Koyck e de correlações canônicas. Os resultados mostraram que há correlação canônica estatisticamente significativa entre os indicadores contábeis antes de vigorar a Lei n.º 11.638 (2007 com os indicadores contábeis após vigorar a Lei n.º 11.638/07. Conclui-se, de maneira geral, de acordo com as empresas pesquisadas, que os indicadores contábeis não sofreram alteração estatisticamente significativa pelo fato de as demonstrações contábeis serem elaboradas atendendo aos preceitos da Lei n.º 11.638 (2007.

  14. Nuclear magnetic resonance studies of intracellular ions in perfused from heart

    International Nuclear Information System (INIS)

    Burnstein, D.; Fossel, E.T.

    1987-01-01

    Intracellular sodium, potassium, and lithium were observed in a perfused frog heart by nuclear magnetic resonance (NMR) spectroscopy. A perfusate buffer containing the shift reagent, dysprosium tripolyphosphate, was used in combination with mathematical filtering or presaturation of the extracellular resonance to separate the intra- and extracellular sodium NMR signals. Addition of 10 μM ouabain to the perfusate, perfusion with a zero potassium, low-calcium buffer, and replacement of 66% of the perfusate sodium with lithium resulted in changes in the intracellular sodium levels. An increase of 45% in the intracellular sodium was observed when changing the pacing rate from 0 to 60 beats/min (with proportional changes for intermediate pacing rates). The ratio of intracellular potassium to sodium concentration was determined to be 2.3 by NMR, indicating that a substantial amount of the intracellular potassium is undetectable with these NMR method. In addition, intracellular lithium was observed during perfusion with a lithium-containing perfusate

  15. Clinical investigation of large perfusion defect cases with 201Tl exercise myocardial scintigraphy

    International Nuclear Information System (INIS)

    Morota, Motoi; Kobayashi, Yasuhiko

    1999-01-01

    We investigated retrospectively the clinical significance of large perfusion defect on 201 Thallium myocardial scintigraphy from the records of 833 patients during the past 3 years from 1991 to 1994. The patients were divided into 3 groups according to the extent of perfusion defect; cases with normal perfusion (n=561), with small perfusion defect (n=211) and with large perfusion defect (n=61). We found that the proportions of cases with large perfusion defect was significantly larger than that of cases with small perfusion defect in myocardial disease (MD; hypertrophic cardiomyopathy, dilated cardiomyopathy, and post myocarditis combined) (P 201 Thallium myocardial scintigraphy and that complication of diabetes mellitus and clinical symptoms may be useful in differentiating IHD from MD. (author)

  16. Coronary Artery Disease: Analysis of Diagnostic Performance of CT Perfusion and MR Perfusion Imaging in Comparison with Quantitative Coronary Angiography and SPECT-Multicenter Prospective Trial.

    Science.gov (United States)

    Rief, Matthias; Chen, Marcus Y; Vavere, Andrea L; Kendziora, Benjamin; Miller, Julie M; Bandettini, W Patricia; Cox, Christopher; George, Richard T; Lima, João; Di Carli, Marcelo; Plotkin, Michail; Zimmermann, Elke; Laule, Michael; Schlattmann, Peter; Arai, Andrew E; Dewey, Marc

    2018-02-01

    Purpose To compare the diagnostic performance of stress myocardial computed tomography (CT) perfusion with that of stress myocardial magnetic resonance (MR) perfusion imaging in the detection of coronary artery disease (CAD). Materials and Methods All patients gave written informed consent prior to inclusion in this institutional review board-approved study. This two-center substudy of the prospective Combined Noninvasive Coronary Angiography and Myocardial Perfusion Imaging Using 320-Detector Row Computed Tomography (CORE320) multicenter trial included 92 patients (mean age, 63.1 years ± 8.1 [standard deviation]; 73% male). All patients underwent perfusion CT and perfusion MR imaging with either adenosine or regadenoson stress. The predefined reference standards were combined quantitative coronary angiography (QCA) and single-photon emission CT (SPECT) or QCA alone. Results from coronary CT angiography were not included, and diagnostic performance was evaluated with the Mantel-Haenszel test stratified by disease status. Results The prevalence of CAD was 39% (36 of 92) according to QCA and SPECT and 64% (59 of 92) according to QCA alone. When compared with QCA and SPECT, per-patient diagnostic accuracy of perfusion CT and perfusion MR imaging was 63% (58 of 92) and 75% (69 of 92), respectively (P = .11); sensitivity was 92% (33 of 36) and 83% (30 of 36), respectively (P = .45); and specificity was 45% (25 of 56) and 70% (39 of 56), respectively (P CT perfusion and MR perfusion imaging was 82% (75 of 92) and 74% (68 of 92), respectively (P = .27); sensitivity was 90% (53 of 59) and 69% (41 of 59), respectively (P perfusion CT is similar to that of perfusion MR imaging in the detection of CAD. © RSNA, 2017 Online supplemental material is available for this article.

  17. Simulation evaluation of quantitative myocardial perfusion assessment from cardiac CT

    Science.gov (United States)

    Bindschadler, Michael; Modgil, Dimple; Branch, Kelley R.; La Riviere, Patrick J.; Alessio, Adam M.

    2014-03-01

    Contrast enhancement on cardiac CT provides valuable information about myocardial perfusion and methods have been proposed to assess perfusion with static and dynamic acquisitions. There is a lack of knowledge and consensus on the appropriate approach to ensure 1) sufficient diagnostic accuracy for clinical decisions and 2) low radiation doses for patient safety. This work developed a thorough dynamic CT simulation and several accepted blood flow estimation techniques to evaluate the performance of perfusion assessment across a range of acquisition and estimation scenarios. Cardiac CT acquisitions were simulated for a range of flow states (Flow = 0.5, 1, 2, 3 ml/g/min, cardiac output = 3,5,8 L/min). CT acquisitions were simulated with a validated CT simulator incorporating polyenergetic data acquisition and realistic x-ray flux levels for dynamic acquisitions with a range of scenarios including 1, 2, 3 sec sampling for 30 sec with 25, 70, 140 mAs. Images were generated using conventional image reconstruction with additional image-based beam hardening correction to account for iodine content. Time attenuation curves were extracted for multiple regions around the myocardium and used to estimate flow. In total, 2,700 independent realizations of dynamic sequences were generated and multiple MBF estimation methods were applied to each of these. Evaluation of quantitative kinetic modeling yielded blood flow estimates with an root mean square error (RMSE) of ~0.6 ml/g/min averaged across multiple scenarios. Semi-quantitative modeling and qualitative static imaging resulted in significantly more error (RMSE = ~1.2 and ~1.2 ml/min/g respectively). For quantitative methods, dose reduction through reduced temporal sampling or reduced tube current had comparable impact on the MBF estimate fidelity. On average, half dose acquisitions increased the RMSE of estimates by only 18% suggesting that substantial dose reductions can be employed in the context of quantitative myocardial

  18. [CT perfusion in patients after EICMA in the postoperative period].

    Science.gov (United States)

    Grigor'eva, E V; Luk'ianchikov, V A; Tokarev, A S; Krylov, V V

    2014-01-01

    To evaluate the influence of the EICMA on the circulation of the brain in patients with unilateral occlusion of the internal carotid artery (ICA) in the late postoperative period using CT perfusion. Ten patients with unilateral internal carotid artery occlusion and stenosis of the opposite ICA 50-60%, with a history of a single ischemic stroke were examined. All patients underwent pre-and postoperative CT angiography of the brachiocephalic and intracranial arteries and CT perfusion. We also compared the results of neurological examinations preoperatively and during the year after the intervention. The neurological data during the first year after surgery demonstrated an improvement of neurological status and quality of life in all patients. Preoperative CT perfusion showed the patchy decrease in the cerebral blood flow (CBF) to 18 ml/100 g/min (average of 44-56 ml/100 g/min) and increase in the mean transit time (MTT) to 7.2 s (normally less 6c) in all cases on the side of occlusion. The most susceptible to chronic ischemic changes was the frontal region, temporal and parietooccipital regions were affected to a lesser extent. Due to stenosis of the opposite ICA, minimum CBF of the cortex in the opposite hemisphere was 24 ml/100 g/min and MTT was increased to 5.6 s. Six months after the applying of EICMA, the significant improvement of CT perfusion was noted on the side of the anastomosis in all patients: an increase in CBF (at least 44 ml/100 g/min) and MTT reduction (up to 6.1s in the frontal region), as well as the "synchronization" of CBF and CBV in similar areas of the cerebral cortex of the right and left hemisphere. CT perfusion in the late postoperative period after applying EICMA in patients with unilateral ICA occlusion demonstrates not only changes of the cerebral perfusion on the side of the occlusion, but also the increased collateral blood flow of the cortex in both hemispheres, which significantly improves brain blood flow generally within 6-12 months

  19. Conventional X-ray examination and computed tomography in inflammatory rheumatic diseases; Roentgendiagnostik und Computertomographie bei entzuendlich-rheumatischen Erkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Lingg, G. [Rheumazentrum Bad Kreuznach (Germany). Zentrales Roentgeninstitut

    1996-08-01

    Plain-film radiography is an important and basic element in the assessment of inflammatory rheumatic diseases. Its various uses include assessment of inflammatory osseous destruction and the activity of inflammatory changes. Furthermore, the inflammatory collateral phenomena can indicate an acute clinical phase, and the articular soft tissue swelling and tenosynovitis are shown directly and indirectly very clearly. On the other hand, high-resolution computed tomography is very capable of showing cortical structures of bone complementary to MR. In some special clinical questions and anatomical regions, especially the axial skeleton, it delivers information of high specifity, partly for definitive diagnosis and partly for planning surgical procedures. The assessment of changes in the sacroiliac joints, sternoclavicular joints and craniocervical junction are domains of computed tomography. (orig.) [Deutsch] Das konventionelle Roentgenbild muss auch heute noch bei klinischer Frage nach entzuendlich-rheumatischer Erkrankung als Basisuntersuchung angesehen werden. Sein Informationspotential umfasst nicht nur knoecherne entzuendliche Destruktionen, sondern es laesst auch deren derzeitige Aktivitaet beurteilen. Weiterhin vermag das Roentgenbild ueber die Kollateralphaenomene auf eine klinische Schubsituation hinzuweisen und die entzuendliche Volumenvermehrung der Gelenke und Sehnenscheiden direkt und indirekt darzustellen. Darueber hinaus bietet die hochaufloesende Computertomographie, insbesondere durch die detaillierte Darstellung kortikaler knoecherner Strukturen - komplementaer zur MR -, bei einigen speziellen Fragestellungen, insbesondere am Stammskelett und an einzelnen grossen Gelenken, hochspezifische Informationen, teils zur definitiven Diagnosestellung, teils auch fuer die Operationsplanung. Dies gilt u.a. fuer die Kreuzdarmbeingelenke, die Sternoklavikulargelenke und die obere HWS. (orig.)

  20. Pengaruh Pengungkapan Intellectual Capital (IC dan Economic Value Added (EVA terhadap Harga Saham Perusahaan Manufaktur yang terdaftar di BEI

    Directory of Open Access Journals (Sweden)

    Achmad Fauzi

    2015-07-01

    Full Text Available This study aims at finding out if The Influence of Intellectual Capital (ICand Economic Value Added (EVA on Stock Price of Manufacturing Companies listed on the Indonesia Stock Exchange (BEI in 2012. The hypothesis of this study is : There is Influence of Intellectual Capital (IC and Economic Value Added (EVA on Stock Price of Manufacturing Company listed on the Indonesia Stock Exchange (BEI in 2012. The method used is the author of the survey method with a quantitative approach . This study population is the entire manufacturing companies listed on the Stock Exchange in 2012 his sampling technique is random sampling as many as 36 samples .. Correlation Coefficient significance test ( Test A of 0.512 , indicating that there is a middle relationship between IC and EVA on Stock Price. The results of the coefficient of determination ( R2 Test stated that R2 is 0.262 or 26.2% . This shows that the percentage contribution of the effect of independent variables ( IC and EVA on the dependent variable ( stock price of 26.2 % . Or variations of the independent variables used in the model ( IC and EVA are able to explain 26.2% of variation in the dependent variable ( stock price . While the remaining 73.8 % are influenced or explained by other variables not included in this research model .

  1. Modeling and Assessment of Precise Time Transfer by Using BeiDou Navigation Satellite System Triple-Frequency Signals

    Directory of Open Access Journals (Sweden)

    Rui Tu

    2018-03-01

    Full Text Available This study proposes two models for precise time transfer using the BeiDou Navigation Satellite System triple-frequency signals: ionosphere-free (IF combined precise point positioning (PPP model with two dual-frequency combinations (IF-PPP1 and ionosphere-free combined PPP model with a single triple-frequency combination (IF-PPP2. A dataset with a short baseline (with a common external time frequency and a long baseline are used for performance assessments. The results show that IF-PPP1 and IF-PPP2 models can both be used for precise time transfer using BeiDou Navigation Satellite System (BDS triple-frequency signals, and the accuracy and stability of time transfer is the same in both cases, except for a constant system bias caused by the hardware delay of different frequencies, which can be removed by the parameter estimation and prediction with long time datasets or by a priori calibration.

  2. [Osteopathie bei gastroösophagealem Reflux mit Hiatushernie: Ein Fallbericht gemäß der CARE-Leitlinie].

    Science.gov (United States)

    Rotter, Gabriele; Brinkhaus, Benno

    2017-01-01

    Hintergrund: Das Vorhandensein einer Hiatushernie kann das Auftreten einer gastroösophagealen Refluxerkrankung (GERD) als Komplikation bedingen. Konventionelle medizinische Therapiemaßnahmen können zu unerwünschten Ereignissen und Rezidiven führen. Bisher sind die Effekte von osteopathischen Behandlungen bei Hiatushernie und GERD nicht bekannt. Fallbericht: Eine 59-jährige Patientin mit endoskopisch diagnostizierter chronischer Gastritis, GERD und Hiatushernie beklagte einen persistierenden gastroösophagealen Reflux trotz konventionell-medizinischer konservativer Therapie. Die osteopathische Diagnostik ergab eine funktionelle Störung im Bereich des Magens und der Kardia mit einer Beteiligung zugehöriger Reflexzonen. Nach einer osteopathischen Behandlung als individuelle, befundorientierte Therapie ließen die Beschwerden erheblich nach. Die Hiatushernie war nach einer dieser Behandlung endoskopisch nicht mehr nachweisbar. Schlussfolgerungen: Dieser Fallbericht schildert die Symptomreduktion einer GERD nach osteopathischer Behandlung. In der endoskopischen Folgeuntersuchung fand sich die initial diagnostizierte Hiatushernie nicht mehr, diese Befund änderung könnte jedoch auf die unterschiedlichen Untersucher zurückgeführt werden. Prospektive kontrollierte klinische Studien sind notwendig, um den Stellenwert von osteopathischen Behandlungen bei GERD mit Hiatushernie zu untersuchen. © 2017 The Author(s). Published by S. Karger GmbH, Freiburg.

  3. Hyperonenproduktion in C+C- und Si+Si-Kollisionen bei 158 GeV pro Nukleon

    CERN Document Server

    Kraus, Ingrid

    2004-01-01

    Ultrarelativistische Schwerionenstöße werden seit etwa 15 Jahren untersucht, um Kernmaterie unter extremen Bedingungen zu erforschen; in Kollisionen schwerer Atomkerne kann bei hohen Einschußenergien Kernmaterie stark komprimiert und aufgeheizt werden. Die Bedeutung dieser Experimente wird durch Berechnungen der Quanten-Chromo-Dynamik auf raumzeitlichen Gittern hervorgehoben, die bei ausreichend hoher Energiedichte eine Phase voraussagen, in der die Quarks nicht mehr in Hadronen gebunden sind, sondern zusammen mit den Gluonen ein partonisches System ausbilden. Ist das System hinreichend groß und equilibriert, wird es als Quark-Gluon-Plasma bezeichnet. Die als Signatur für das Überschreiten der Phasengrenze vorgeschlagene erhöhte Produktion Seltsamkeit tragender Teilchen wurde in der Gegenüberstellung von elementaren Proton+Proton-Interaktionen und Kern+Kern-Stößen experimentell über einen weiten Energiebereich bestätigt. Eine solche Überhöhung kann aber auch durch rein hadronische Phänomene her...

  4. Detection of coronary calcium with electron beam tomography in coronary artery disease; Stellenwert der Kalkbestimmung mit Elektronenstrahltomographie bei koronarer Herzkrankheit

    Energy Technology Data Exchange (ETDEWEB)

    Haberl, R.; Knez, A.; Becker, A. [Muenchen Univ. (Germany). Medizinische Klinik 1; Becker, C.; Bruening, R.; Reiser, M. [Muenchen Univ. (Germany). Inst. fuer Radiologische Diagnostik; Maass, A.; Steinbeck, G.

    1998-12-01

    patients with known risk factors, in whom primary preventive strategies could be performed more selectively and cost-effectively. (orig./AJ) [Deutsch] Zielsetzung: Koronarer Kalk ist Hinweis auf einen arteriosklerotischen Prozess und kann mit Elektronenstrahltomographie sehr genau erfasst werden. Der klinische Stellenwert unterscheidet sich je nachdem, ob das Kalkscreening bei Patienten mit schon bekannter koronarer Herzkrankheit oder bei asymptomatischen Patienten zur Primaerpraevention durchgefuehrt wird. Ergebnisse: Am Klinikum Grosshadern wurden in dem einen Jahr nach Inbetriebnahme der EBT bei 1100 Patienten ein EBT des Herzens vorgenommen, bei 567 Patienten im direkten Vergleich zur Koronarangiographie ({+-}3 Tage). In Uebereinstimmung mit der Literatur findet sich eine Abhaengigkeit des Kalkscores vom Alter und Geschlecht der Patienten. Schwere koronare Herzerkrankungen (Stenosen {>=} 75%) sind mit signifikant mehr Kalk verbunden als KHK niedrigen Schweregrades. Eine Unterscheidung zwischen 1-, 2- und 3-Gefaess-Erkrankung mit dem Kalkscore gelingt nicht. Unter Verwendung eines alterskorrigierten Kalkscores werden 33% der Patienten mit signifikanter KHK nicht erfasst, immerhin 8,1% der Patienten mit hochgradigen Stenosen weisen keinerlei Kalk (Score=0) auf. Es liegen nur wenige Studien zum Stellenwert der Kalkbestimmung bei asymptomatischen Patienten vor. Weiche Plaques koennen mit der EBT nicht erfasst werden, offensichtlich kommen `harte` (=verkalkte) und weiche Plaques bei der ueberwiegenden Mehrzahl der Patienten gemeinsam vor. Spiral-CT der neuesten Generatoren erfasst koronaren Kalk mit grosser Praezision. Es besteht eine exzellente Korrelation zur EBT. Diskussion: Der Nachweis von koronarem Kalk weist mit hoher Sicherheit auf eine koronare Herzkrankheit hin. Indikationsgebiete der EBT erstrecken sich auf Patienten mit bekannter koronarer Herzkrankheit (Kalkscore korreliert mit der Prognose), Patienten, bei denen eine konventionelle Belastungsuntersuchung nicht

  5. Correction Model of BeiDou Code Systematic Multipath Errors and Its Impacts on Single-frequency PPP

    Directory of Open Access Journals (Sweden)

    WANG Jie

    2017-07-01

    Full Text Available There are systematic multipath errors on BeiDou code measurements, which are range from several decimeters to larger than 1 meter. They can be divided into two categories, which are systematic variances in IGSO/MEO code measurement and in GEO code measurement. In this contribution, a methodology of correcting BeiDou GEO code multipath is proposed base on Kalman filter algorithm. The standard deviation of GEO MP Series decreases about 10%~16% after correction. The weight of code in single-frequency PPP is great, therefore, code systematic multipath errors have impact on single-frequency PPP. Our analysis indicate that about 1 m bias will be caused by these systematic errors. Then, we evaluated the improvement of single-frequency PPP accuracy after code multipath correction. The systematic errors of GEO code measurements are corrected by applying our proposed Kalman filter method. The systematic errors of IGSO and MEO code measurements are corrected by applying elevation-dependent model proposed by Wanninger and Beer. Ten days observations of four MGEX (Multi-GNSS Experiment stations are processed. The results indicate that the single-frequency PPP accuracy can be improved remarkably by applying code multipath correction. The accuracy in up direction can be improved by 65% after IGSO and MEO code multipath correction. By applying GEO code multipath correction, the accuracy in up direction can be further improved by 15%.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-01-15

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

  7. Dynamic volume perfusion CT in patients with lung cancer: Baseline perfusion characteristics of different histological subtypes

    International Nuclear Information System (INIS)

    Shi, Jingyun; Schmid-Bindert, Gerald; Fink, Christian; Sudarski, Sonja; Apfaltrer, Paul; Pilz, Lothar R.; Liu, Bo; Haberland, Ulrike; Klotz, Ernst

    2013-01-01

    Objective: To evaluate dynamic volume perfusion CT (dVPCT) tumor baseline characteristics of three different subtypes of lung cancer in untreated patients. Materials and methods: 173 consecutive patients (131 men, 42 women; mean age 61 ± 10 years) with newly diagnosed lung cancer underwent dVPCT prior to biopsy. Tumor permeability, blood flow (BF), blood volume (BV) and mean transit time (MTT) were quantitatively assessed as well as tumor diameter and volume. Tumor subtypes were histologically determined and compared concerning their dVPCT results. dVPCT results were correlated to tumor diameter and volume. Results: Histology revealed adenocarcinoma in 88, squamous cell carcinoma in 54 and small cell lung cancer (SCLC) in 31 patients. Tumor permeability was significantly differing between adenocarcinoma, squamous cell carcinoma and SCLC (all p < 0.05). Tumor BF and BV were higher in adenocarcinomathan in SCLC (p = 0.001 and p = 0.0002 respectively). BV was also higher in squamous cell carcinoma compared to SCLC (p = 0.01). MTT was not differing between tumor subtypes. Regarding all tumors, tumor diameter did not correlate with any of the dVPCT parameters, whereas tumor volume was negatively associated with permeability, BF and BV (r = −0.22, −0.24, −0.24, all p < 0.05). In squamous cell carcinoma, tumor diameter und volume correlated with BV (r = 0.53 and r = −0.40, all p < 0.05). In SCLC, tumor diameter und volume correlated with MTT (r = 0.46 and r = 0.39, all p < 0.05). In adenocarcinoma, no association between morphological and functional tumor characteristics was observed. Conclusions: dVPCT parameters are only partially related to tumor diameter and volume and are significantly differing between lung cancer subtypes

  8. Assessment of the relationship between morphological emphysema phenotype and corresponding pulmonary perfusion pattern on a segmental level

    Energy Technology Data Exchange (ETDEWEB)

    Bryant, Mark; Kauczor, Hans-Ulrich [University of Heidelberg, Department of Diagnostic and Interventional Radiology, Heidelberg (Germany); Member of German Lung Research Center DZL, Translational Lung Research Center TLRC-H, Heidelberg (Germany); Ley, Sebastian [Chirurgische Klinik Dr. Rinecker, Department of Diagnostic and Interventional Radiology, Munich (Germany); Ludwig Maximilians University, Department of Clinical Radiology, Munich (Germany); Eberhardt, Ralf; Herth, Felix [Thoraxklinik University of Heidelberg, Department of Pneumology and Critical Care Medicine, Heidelberg (Germany); Member of German Lung Research Center DZL, Translational Lung Research Center TLRC-H, Heidelberg (Germany); Menezes, Ravi [University of Toronto, Medical Imaging, Toronto (Canada); Sedlaczek, Oliver [University of Heidelberg, Department of Diagnostic and Interventional Radiology, Heidelberg (Germany); German Cancer Research Center, Department of Radiology, Heidelberg (Germany); Member of German Lung Research Center DZL, Translational Lung Research Center TLRC-H, Heidelberg (Germany); Ley-Zaporozhan, Julia [University of Heidelberg, Department of Diagnostic and Interventional Radiology, Heidelberg (Germany); Ludwig Maximilians University, Department of Clinical Radiology, Munich (Germany)

    2015-01-15

    Distinct morphological emphysema phenotypes were assessed by CT to show characteristic perfusion defect patterns. Forty-one patients with severe emphysema (GOLD III/IV) underwent three-dimensional high resolution computed tomography (3D-HRCT) and contrast-enhanced magnetic resonance (MR) perfusion. 3D-HRCT data was visually analyzed for emphysema phenotyping and quantification by consensus of three experts in chest-radiology. The predominant phenotype per segment was categorized as normal, centrilobular, panlobular or paraseptal. Segmental lung perfusion was visually analyzed using six patterns of pulmonary perfusion (1-normal; 2-mild homogeneous reduction in perfusion; 3-heterogeneous perfusion without focal defects; 4-heterogeneous perfusion with focal defects; 5-heterogeneous absence of perfusion; 6-homogeneous absence of perfusion), with the extent of the defect given as a percentage. 730 segments were evaluated. CT categorized 566 (78 %) as centrilobular, 159 (22 %) as panlobular and 5 (<1 %) as paraseptal with no normals. Scores with regards to MR perfusion patterns were: 1-0; 2-0; 3-28 (4 %); 4-425 (58 %); 5-169 (23 %); 6-108 (15 %). The predominant perfusion pattern matched as follows: 70 % centrilobular emphysema - heterogeneous perfusion with focal defects (score 4); 42 % panlobular - homogeneous absence of perfusion (score 5); and 43 % panlobular - heterogeneous absence of perfusion (score 6). MR pulmonary perfusion patterns correlate with the CT phenotype at a segmental level in patients with severe emphysema. (orig.)

  9. CT findings in acute small bowel diverticulitis; Computertomographie bei akuter Duenndarmdivertikulitis

    Energy Technology Data Exchange (ETDEWEB)

    Ferstl, F.J.; Obert, R. [Radiologisch-Nuklearmedizinisches Zentrum (RNZ) am St. Theresienkrankenhaus Nuernberg (Germany)

    2004-02-01

    radiologische Verfahren gesichert werden, wobei die CT die Methode der Wahl darstellt. Das vorwiegend in Form von Kasuistiken beschriebene Spektrum der CT-Morphologie der akuten Duenndarmdivertikulitis variiert je nach Ausmass des Entzuendungsprozesses. Als typische CT-Befunde finden sich ein entzuendetes Divertikel, peridivertikulaere Fettgewebsinfiltrationen, extraluminale Luftansammlungen als Zeichen einer gedeckten Perforation und ein Wandoedem des betroffenen Duenndarmsegmentes mit vermehrter Distanzierung der Darmschlingen. In sehr seltenen Faellen kann auch ein Enterolith in einem entzuendeten Divertikel nachweisbar sein. An Komplikationen koennen Abszesse, Fisteln, ein Ileus und eine freie Perforation mit Peritonitis auftreten. Diagnostische Probleme bereitet die Duenndarmdivertikulitis von allem bei Lokalisation im terminalen Ileum und im Meckel-Divertikel. Zur Sicherung der computertomographischen Verdachtsdiagnose einer akuten Duenndarmdivertikulitis koennen ein Enteroklysma bzw. beim Meckel-Divertikel eine 99m-Technetium-Pertechnetat-Szintigraphie eingesetzt werden. Wir beschreiben die CT-Befunde zweier Patientinnen mit akuter Jejunumdivertikulitis und eines Patienten mit Meckel-Divertikulitis und vergleichen die Ergebnisse mit den Angaben aus der Literatur. (orig.)

  10. Importance of diffusion imaging in liver metastases; Bedeutung der Diffusionsbildgebung bei Lebermetastasen

    Energy Technology Data Exchange (ETDEWEB)

    Riffel, P.; Schoenberg, S.O.; Krammer, J. [Medizinische Fakultaet Mannheim der Universitaet Heidelberg, Institut fuer Klinische Radiologie und Nuklearmedizin, Universitaetsmedizin Mannheim, Mannheim (Germany)

    2017-05-15

    generieren. Bei der Detektion fokaler Leberlaesionen zeigt die DWI eine bessere Detektionsrate im Vergleich zu T2w-Sequenzen und eine etwas schlechtere Detektionsrate im Vergleich zu dynamischen T1w-Sequenzen. Prinzipiell ist es mit der DWI moeglich, maligne Leberlaesionen von benignen zu unterscheiden sowie ein Therapieansprechen fruehzeitig zu detektieren. Sowohl fuer die Detektion als auch fuer die Charakterisierung fokaler Leberlaesionen stellt die DWI eine vielversprechende Alternative zu den morphologischen Sequenzen dar. Insbesondere fuer die Charakterisierung solider benigner Laesionen sollte jedoch deren naehere Charakterisierung unter Zuhilfenahme weiterer Sequenzen erfolgen. Fuer die Beurteilung und die Prognose eines Therapieansprechens bietet die DWI Vorteile im Vergleich zu den rein morphologischen Sequenzen. Zur reinen Detektion fokaler Leberlaesionen ist die DWI prinzipiell ausreichend. Nach visueller Detektion einer soliden Leberlaesion sollte deren naehere Charakterisierung unter Zuhilfenahme weiterer Sequenzen (insbesondere dynamischer T1w-Sequenzen) erfolgen. Fuer die Beurteilung und die Prognose eines Therapieansprechens sollte die DWI herangezogen werden. (orig.)

  11. Development trends in municipal sewage treatment - an overview; Entwicklungstendenzen bei der kommunalen Abwasserreinigung - ein Ueberblick

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, M. [Technische Hochschule Darmstadt (Germany). Inst. fuer Wasserversorgung, Abwasserbeseitigung und Raumplanung

    1999-07-01

    After the extensive introduction of nutrient elimination at German sewage treatment plants and, on the other hand, with the partly immense backlog in other parts of the world in the erection of sewage treatment plants, no one can tell at present whether traditional activated sludge techniques or modern biofilm techniques or combinations of both will take the lead in the future. Answering this question depends decisively on whether the further development of these techniques meets ecological demands such as the conservation of primary energy or cuts in the addition of chemicals (precipitation agents, methanol). Sustainable sewage treatment techniques need to make careful use of resources and to reduce the amount of additives. In the future, care must be taken not to discharge waste water after cleaning into a receiving body of water but to recycle it. Normally, cleaned waste water will be used for irrigation; under certain circumstances it may be used again as drinking water after the most scrupulous cleaning and additional underground passage or blending with ground water. Approaches to the optimization of different waste water treatment techniques need to be viewed in the context of this indispensable requirement. (orig.) [German] Nach der flaechendeckenden Einfuehrung der Naehrstoffelimination in Deutschland, aber einem teilweise immensen Nachholbedarf bei der Errichtung von Abwasserbehandlungsanlagen in anderen Teilen der Welt, steht die Abwassertechnik vor der Frage, ob das traditionelle Belebungsverfahren oder moderne Biofilmverfahren oder Kombinationen beider Verfahren zukuenftig an Bedeutung gewinnen. Die Beantwortung dieser Fragestellung haengt in entscheidender Weise davon ab, ob die Weiterentwicklung dieser Verfahren oekologischen Anforderungen wie z.B. Einsparung von Primaerenergie oder Reduzierung der Zugabe von Chemikalien (Faellmittel, Methanol) gerecht wird. Mit zukunftstraechtigen Abwasserbehandlungsverfahren muss Abwasser ressourcenschonend

  12. Non-ischemic perfusion defects due to delayed arrival of contrast material on stress perfusion cardiac magnetic resonance imaging after coronary artery bypass graft surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeo Koon; Park, Eun Ah; Park, Sang Joon; Cheon, Gi Jeong; Lee, Whal; Chung, Jin Wook; Park, Jae Hyung [Seoul National University Hospital, Seoul (Korea, Republic of)

    2014-04-15

    Herein we report about the adenosine stress perfusion MR imaging findings of a 50-year-old man who exhibited two different perfusion defects resulting from two different mechanisms after a coronary artery bypass surgery. An invasive coronary angiography confirmed that one perfusion defect at the mid-anterior wall resulted from an ischemia due to graft stenosis. However, no stenosis was detected on the graft responsible for the mid-inferior wall showing the other perfusion defect. It was assumed that the perfusion defect at the mid-inferior wall resulted from delayed perfusion owing to the long pathway of the bypass graft. The semiquantitative analysis of corrected signal-time curves supported our speculation, demonstrating that the rest-to-stress ratio index of the maximal slope of the myocardial territory in question was similar to those of normal myocardium, whereas that of myocardium with the stenotic graft showed a typical ischemic pattern. A delayed perfusion during long graft pathway in a post-bypass graft patient can mimick a true perfusion defect on myocardial stress MR imaging. Radiologists should be aware of this knowledge to avoid misinterpretation of graft and myocardial status in post bypass surgery patients.

  13. Low-Dose Volume-Perfusion CT of the Brain: Effects of Radiation Dose Reduction on Performance of Perfusion CT Algorithms.

    Science.gov (United States)

    Othman, A E; Afat, S; Brockmann, C; Nikoubashman, O; Bier, G; Brockmann, M A; Nikolaou, K; Tai, J H; Yang, Z P; Kim, J H; Wiesmann, M

    2017-09-01

    We aimed to compare different computed tomography (CT) perfusion post-processing algorithms regarding image quality of perfusion maps from low-dose volume perfusion CT (VPCT) and their diagnostic performance regarding the detection of ischemic brain lesions. We included VPCT data of 21 patients with acute stroke (onset Perfusion maps (cerebral blood volume (CBV); cerebral blood flow (CBF) from original and low-dose datasets were generated using two different commercially available post-processing methods: deconvolution-based method (DC) and maximum slope algorithm (MS). The resulting DC and MS perfusion</