Search results for "COMPUTED TOMOGRAPHY"
showing 10 items of 713 documents
Computertomographie der Nieren nach Tumorenukleation
1994
Two weeks to 120 months after enucleation of renal tumours the postoperative defects were correctly localized by renal computed tomography in 34 patients. Typical defect morphology was either wedge-shaped or concave. No dependence on tumour localization, tumour size, operative technique or a certain surgeon was observed. The cortical defects were smaller (mean 2.0 cm) than the original, prominent tumours (mean 3.4 cm). In small defects without tension suture of the capsule is sufficient, leading to minor defects. Larger defects were closed with a retroperitoneal or free peritoneal fat flap resulting in larger residual defects. In case of intra- or postoperative bleeding, CT could demonstrat…
Evaluation eines neuen Softwareassistenten zur automatischen Volumenbestimmung von intrahepatischen Tumoren
2004
Purpose: Computed tomography has become the preferred method in detecting liver carcinomas. The introduction of spiral CT added volumetric assessment of intrahepatic tumors, which was unattainable in the clinical routine with incremental CT due to complex planimetric revisions and excessive computing time. In an ongoing clinical study, a new software tool was tested for the automatic detection of tumor volume and the time needed for this procedure. Materials and Methods: We analyzed patients suffering from hepatocellular carcinoma (HCC). All patients underwent treatment with repeated transcatheter chemoembolization of the hepatic arteria. The volumes of the HCC lesions detected in CT were m…
A CAD system for nodule detection in low-dose lung CTs based on region growing and a new active contour model
2007
A computer-aided detection (CAD) system for the selection of lung nodules in computer tomography (CT) images is presented. The system is based on region growing (RG) algorithms and a new active contour model (ACM), implementing a local convex hull, able to draw the correct contour of the lung parenchyma and to include the pleural nodules. The CAD consists of three steps: (1) the lung parenchymal volume is segmented by means of a RG algorithm; the pleural nodules are included through the new ACM technique; (2) a RG algorithm is iteratively applied to the previously segmented volume in order to detect the candidate nodules; (3) a double-threshold cut and a neural network are applied to reduce…
Repräsentiert der HRCT-Emphysemindex die gesamte Lunge?
2005
Purpose: Comparison of emphysema index derived of thin section MD-CT of the entire lung volume and HRCT, simulated by calculation of every twentieth image of the whole data-set. Materials and Methods: Pulmonary emphysema was quantified by semiautomatic, segmentation of lung borders and assessment of lung volume and emphysema volume within these borders. The emphysema index (pixel index) was calculated. Statistical analysis was done by the sign-test and Bland-Altman-analysis. Results: Median lung volume, emphysema volume and emphysema index are significantly higher in simulated HRCT. Median lung volume (emphysema volume) calculated by HRCT is 5118 ml (407 ml) and 5040 ml (367 ml) calculated …
Accuracy of ultrasonography in the diagnosis of acute calculous cholecystitis: review of the literature.
2013
Background To evaluate the accuracy of ultrasonography in the diagnosis of acute calculous cholecystitis in comparison with other imaging modalities. Methods The authors performed a search of the Medline/ PubMed (National Library of Medicine, Bethesda, Maryland) for original research and review publications examining the accuracy of ultrasonography in the diagnosis of acute calculous cholecystitis. The search design utilized a single or combination of the following terms : (1) acute cholecystitis, (2) ultrasonography, (3) computed tomography, (4) magnetic resonance cholangiopancreatography and (5) cholescintigraphy. This review was restricted to human studies and to English-language literat…
Graph-matching based CTA.
2009
Separating bone, calcification, and vessels in computer tomography angiography (CTA) allows for a detailed diagnosis of vessel stenosis. This paper presents a new, graph-based technique that solves this difficult problem with high accuracy. The approach requires one native data set and one that is contrast enhanced. On each data set, an attributed level-graph is derived and both graphs are matched by dynamic programming to differentiate between bone, on one hand side, and vessel/calcification on the other hand side. Lumen and calcified regions are then separated by a profile technique. Evaluation is based on data from vessels of pelvis and lower extremities of elderly patients. Due to subst…
Imaging of “Malignant” External Otitis
1997
“Malignant” external otitis or necrotizing external otitis (NEO) is a rare and severe infection of the external auditory meatus, causing destructive changes of the petrous bone, infiltrating inframastoid and intracranial tissues, with potentially lethal consequences. Five male diabetic patients, aged 61 to 85 years-old (mean age was 74 y.o), referred with biopsy-proven NEO, underwent CT and MRI studies for the assessment of the extension of the disease. Clinical data concerning the examined patients are summarized in table 1. Contrast-enhanced MRI does not seem to help in differentiating granulation from neoplastic tissues, as both demonstrate inhomogeneous enhancement. In conclusion, NEO …
Optic nerve hypoplasia and internal carotid artery hypoplasia: a new association
2017
Effects of diet-induced obesity and voluntary wheel running on the microstructure of the murine distal femur
2011
Abstract Background Obesity and osteoporosis, two possibly related conditions, are rapidly expanding health concerns in modern society. Both of them are associated with sedentary life style and nutrition. To investigate the effects of diet-induced obesity and voluntary physical activity we used high resolution micro-computed tomography (μCT) together with peripheral quantitative computed tomography (pQCT) to examine the microstructure of the distal femoral metaphysis in mice. Methods Forty 7-week-old male C57BL/6J mice were assigned to 4 groups: control (C), control + running (CR), high-fat diet (HF), and high-fat diet + running (HFR). After a 21-week intervention, all the mice were sacrifi…
Hepatic Sinusoidal Dilatation: A Review of Causes With Imaging-Pathologic Correlation.
2016
Hepatic sinusoids are vascular conduits connecting the portal triad with the central vein. Multiple conditions can lead to sinusoidal dilatation and congestion with resultant stasis of blood within the lumen. The altered hemodynamics associated with hepatic sinusoidal dilatation generally result in heterogeneous enhancement of the hepatic parenchyma on contrast-enhanced computed tomography and magnetic resonance imaging, a pattern often described as “mosaic” enhancement. In this article, we review the causes of hepatic sinusoidal dilatation and the imaging manifestations on contrast-enhanced computed tomography and magnetic resonance.