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排序方式: 共有471条查询结果,搜索用时 31 毫秒
51.
B. Riemann J. Menzel U. Schiemann W. Domschke J. W. Konturek 《Scandinavian journal of gastroenterology》2013,48(1):102-107
Background: Ultrasound-guided biopsies of abdominal organs are not without risks for the patients; in particular, hemorrhagic complications may occur. Thus, over the last few years, automatic biopsy guns have been developed to facilitate the biopsy process. Methods: The aim of our retrospective study was to examine the quality of specimens and the complication rate of ultrasound-guided biopsies of abdominal organs carried out in our institution using the automatic Autovac biopsy system during a period of 1.5 years. Of the total number of 321 biopsies, 290 were performed with the 1.2-mm Autovac needle, and in 31 cases the 0.95-mm needle was used. Among the 321 biopsies there were 211 of the liver parenchyma (66%), 47 of a liver tumor (14%), 38 of the pancreas (12%), 15 of the kidney parenchyma (5%), and 10 of a retroperitoneal tumor (3%). Results: In 310 of the 321 biopsies it was possible to obtain sufficient diagnostically usable material for the pathologist (96.6%). In the other 11 cases the material obtained did not enable proper histologic diagnosis (3.4%). Two of these 11 biopsies were carried out with the 0.95-mm needle, and the other 9 with the 1.2-mm needle.Twenty-four hours after the biopsy each patient underwent routine ultrasound examination to exclude a possible bleeding. In eight cases an afterbleeding occurred (total hemorrhagic rate, 2.5%), four times without clinical consequences. The other four bleeding complications were more serious (1.2% of all taps), and all occurred after liver biopsies in patients with a history of liver complaints and abnormal clotting variables. There were no fatalities among our biopsies (mortality rate, 0%). Conclusion: The automatic Autovac biopsy system is suitable and relatively safe for obtaining sufficient histopathologic material from intra-abdominal organs. 相似文献
52.
A retrospective morphologic study of 80 cases was undertaken to determine factors affecting detectability of computed tomographically (CT) proved aortopulmonary (AP) window lesions on conventional posteroanterior (PA) and lateral chest radiographs. Criteria used for determining abnormality were: solitary lymph node enlargement over 1.5 cm or three or more 1-cm nodes and obvious large masses or vascular anomalies. CT scans and corresponding PA and lateral radiographs were analyzed for lesion detectability, size, and location. In 49% of cases there was no detectable lesion in the AP window on radiographs; a definite AP window lesion was seen in 41%, and 10% were equivocal. Major contributing factors to low detectability of AP window lesions on radiographs include size and, more important, location of the lesion. An additional 45 cases of CT-proved normal AP windows were retrospectively reviewed to determine the false-positive rate of PA and lateral radiographs in detection of AP window lesions: 43 (96%) were classified as negative, the remaining two (4%) as equivocal. Although the AP window is a small space, it is the site of many pathologic conditions; the study results indicate that CT may be an essential procedure for its evaluation. 相似文献
53.
Wang KY; Kimmey MB; Nyberg DA; Mack LA; Haggitt RC; Shuman WP; Franklin DW; Silverstein FE 《Radiology》1987,165(3):827-829
Six normal and 16 neoplastic colorectal specimens were examined with 8.5-MHz ultrasound (US). An articulated system facilitated precise spatial correlation between US and histologic sections. Images were blindly interpreted and then compared with histologic results. All six normal specimen showed five distinct echo layers and were distinguished from neoplastic specimens by all the observers. The central echogenic layer, corresponding to the submucosa, is useful in determining the depth of origin of a neoplasm and the presence of submucosal invasion. US had an accuracy of 92.5% in demonstrating invasion of the submucosa and 77% for invasion of the muscularis externa. For mucosal neoplasms with invasion through the muscularis externa and extension into the subserosal tissues, nearly 90% of US interpretations were correct. High-frequency US may be useful in determining the depth of invasion of mucosal tumors with respect to the submucosa and in differentiating mucosal from extramural masses. 相似文献
54.
Mastromatteo JF; Mindell HJ; Mastromatteo MF; Magnant MB; Sturtevant NV; Shuman WP 《Radiology》1997,202(2):523
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Sclerosing cholangitis: CT findings 总被引:5,自引:0,他引:5
The value of computed tomography (CT) in the detection of primary sclerosing cholangitis (PSC) in the intrahepatic and extrahepatic biliary systems was assessed by comparing CT scans of 20 cases of PSC with cholangiographic findings. In 16 of 19 cases of extrahepatic duct disease demonstrated with cholangiography, CT demonstrated abnormalities of the common hepatic duct, or bile duct, including duct stenosis, mural nodularity, duct dilatation, wall thickening, and mural enhancement. CT demonstrated intrahepatic disease in all 20 cases, including duct dilatation, duct stenosis, pruning, and beading. CT was superior to cholangiography in characterization of the status of the intrahepatic duct system in 11 of 20 cases. In addition, CT demonstrated extrabiliary complications of PSC in 12 cases and superimposed cholangiocarcinoma in three cases. While cholangiography remains the standard for diagnosis and follow-up of PSC, CT can provide valuable information about the extent and complications of the disease. 相似文献