Search results for "Loo"

Clinical significance of the quantitative and qualitative determination of the cerebral blood flow through the use of isotopes

1966

Es wird über die bisher entwickelten Methoden zur bestimmung der Hirndurchblutung mit radioaktiven Isotopen berichtet, wobei die quantitativen Untersuchungsmethoden hinsichtlich ihrer klinischen Bedeutung den qualitativen gegenübergestellt werden. Während die quantitativen Methoden eine genaue Bestimmung des cerebralen Blutvolumens und damit der Gesamtdurchblutung des Hirns bzw. bestimmter Hirnareale ermöglichen, bieten die qualitativen Untersuchungsmethoden hinsichtlich der klinisch-diagnostischen Aussagekraft besondere Vorteile. Aus der Bestimmung der Zirkulationszeit des Hirns und dem Verlauf der über beiden Hemisphären registrierten Aktivitätskurven lassen sich differenzial-diagnostisch…

Colorectal Polyps

2008

Publisher Summary Colorectal cancer (CRC) remains the second leading cause of cancer death for both women and men with more than 130,000 newly diagnosed cases and 50,000 deaths each year in the United States alone. Most colon cancers develop from nonmalignant colonic adenomas or polyps over a comparatively long time period ranging between 24 and 60 months. Reflecting this adenomatous pathogenesis of most colorectal cancers, polyp screening with subsequent polypectomy is used to constitute an effective approach for decreasing the incidence of this malignant tumor. Thus, colorectal screening for polyps may be considered one of the most promising preventive measures in medicine. Most available…

Determination of myocardial perfusion and coronary flow reserve by densitometric measurements: a selective classification of regions of interest

2002

To evaluate the functional effect of a coronary artery stenosis on the dependent myocardium, digitized coronary angiograms (DCAs) were recorded. The DCAs, acquired during heart catheterization, provide information about myocardial perfusion and coronary flow reserve of areas supplied by this coronary artery. For each analysis the myocardium is separated into different regions of interest (ROIs); 16 ROIs in the distribution of the LCA and 8 ROIs for the RCA. In addition to that, the ROIs of the diseased vessels are divided into ROIs which are proximal, within and distal to the stenosis. Using a semiautomatic procedure, densograms are constructed from which the parameter rise time is calculat…

Rare <i>Atg7</i> Genetic Variants Predispose to Severe Fatty Liver Disease

2021

Background&Aims: Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease and has a strong heritable component. The aim of this study was to identify new genes involved in NAFLD pathogenesis. Methods: We examined rare variants captured by whole-exome sequencing in individuals with severe fibrosis or hepatocellular carcinoma due to NAFLD (severe NAFLD, n=301) after variant prioritization.  We replicated the results in the UK Biobank and the Liver biopsy cohort (n=2268). Results: We observed an enrichment of the p.P426L variant (rs143545741 C>T; OR=7.2, 2.3-17.3; p C; MAF=0.060 vs. 0.035; OR=1.7, 1.2-2.5; p=0.003). In the UK Biobank cohort, the p.V471A variant wa…

Commentary to Ceresoli M, Tamini N, Gianotti L et al. “Are endoscopic loop ties safe even in complicated acute appendicitis? A systematic review and …

2019

Resting myocardial blood flow quantification using contrast-enhanced magnetic resonance imaging in the presence of stenosis: A computational fluid dy…

2015

Purpose: The extent to which atherosclerotic plaques affect contrast agent (CA) transport in the coronary arteries and, hence, quantification of myocardial blood flow (MBF) using magnetic resonance imaging (MRI) is unclear. The purpose of this work was to evaluate the influence of plaque induced stenosis both on CA transport and on the accuracy of MBF quantification. Methods: Computational fluid dynamics simulations in a high-detailed realistic vascular model were employed to investigate CA bolus transport in the coronary arteries. The impact of atherosclerosis was analyzed by inserting various medium- to high-grade stenoses in the vascular model. The influence of stenosis morphology was ex…

Transkranielle Dopplersonographie bei Kopf-Hals-Tumoren*

1991

Transcranial Doppler ultrasound (TCD) recording is a non-invasive diagnostic procedure for the evaluation of the cerebral collateral flow in patients, in whom therapeutic ligation or resection of the common and/or internal carotid artery is planned. Patients are first examined under resting conditions, and then under manual compression of the ipsilateral carotid artery. Since January 1989, 31 ENT and neurosurgical patients have been examined. In all patients an immediate decrease in flow velocity in the middle cerebral artery (mca) of about 25% to 90% was recorded. In 42.8% of the patients the mca flow velocity reached 90% or more of its value under normal conditions within a short period. …

Evaluation von Nierenarterienstenosen: Vergleich von Angiographie mit invasiver Blutdruckmessung und Doppler-Sonographie

2000

Ziel: Der bei einer Nierenarterien-Angioplastie angiographisch gemessene Stenosegrad soll mit dem transstenotischen Blutdruck-Gradienten und dem prainterventionellen dopplersonographischen Befund verglichen werden. Methoden: Anhand von insgesamt 46 Nierenarterienstenosen bei 35 Patienten mit renovaskularer Hypertonie werden die angiographisch-morphologischen Befunde („linearer”, „geometrischer” und „densitometrischer” Stenosegrad) mit der invasiven transstenotischen Blutdruckmessung und den prainterventionellen Doppler-Befunden verglichen. Ergebnisse: Alle angiographisch bestimmten Stenosegrade korrelieren - masig - mit den transstenotischen Druckgradienten (Korrelationskoeffizienten: 0,67 …

[CT-angiography in carotid stenosis].

1997

Purpose: Prospective evaluation of the accuracy of CT angiography (CTA) with different postprocessing for extracranial carotid artery in comparison with DSA. Method: one hundred patients were studied with standarized CTA. For postprocessing, MPR, MIP, and 3D reconstruction based on segmentation with upper and lower threshold were used. Intravascular density profiles were considered. All CTA studies were correlated with intra-arterial angiography. The degree and classification of stenoses was determined using the guidelines established by the NASCET collaborators. Results: Measurement of stenosis was possible by MPR in 82.5 %, by MIP in 85 %, and 3D in 100 %. Correct classification was found…

Effects of Ciprostene on Restenosis Rate during Therapeutic Transluminal Coronary Angioplasty

1992

Ciprostene, a chemically stable prostacyclin analog was studied for its effects on restenosis in patients with coronary artery disease undergoing therapeutic percutaneous transluminal coronary angioplasty (PTCA). In a double-blind, randomized trial 32 patients were randomized to receive either ciprostene or the respective placebo. The infusion started intracoronarily at a rate of 40 ng/kg/min 20 min before introduction of the balloon catheter into the coronary artery. Thereafter infusion was continued intravenously for 36 hours at a rate of 120 ng/kg/min and a tapering off period until 48 hours. The quantitative analyses of the degree of coronary artery stenoses on the angiographic films be…