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131.
Psoas muscle disorders: MR imaging 总被引:3,自引:0,他引:3
Nineteen patients with evidence of psoas and iliopsoas abnormalities on computed tomographic (CT) scans (12 with metastases, three with lymphoma, two with hematoma, and two with abscess) were examined with magnetic resonance (MR) imaging. The abnormal psoas could be identified on both T1- and T2-weighted spin-echo images, although T2-weighted sequences provided better contrast. The psoas muscle can be affected by one of three mechanisms: total replacement, lateral displacement, or medial displacement. In four patients in whom the CT study showed apparent enlargement of a psoas muscle, subsequent MR imaging examinations demonstrated that the psoas muscle was compressed and displaced laterally by a paraspinal mass. MR images provided better contrast between the normal and abnormal psoas than CT scans in nine cases; MR images were inferior to CT scans in two cases because calcifications (one case) and air bubbles within an abscess (one case) were not detectable. 相似文献
132.
Hepatic metastases studied with MR and CT 总被引:1,自引:0,他引:1
Examinations of the liver using magnetic resonance (MR) and computed tomography (CT) were performed on 50 patients with hepatic metastases. MR and CT were comparable in their ability to detect metastases, which generally appeared hypointense compared with normal liver parenchyma on T1-weighted MR images and hyperintense on T2-weighted images. The MR imaging techniques that were most reliable in detecting metastases were inversion recovery and a relatively T2-weighted, spin-echo technique (TR = 1,500 msec, TE = 60 msec). We conclude that CT, because of its shorter imaging time, greater spatial resolution, and lower cost, should remain the preferred screening test for hepatic metastases. MR imaging should be reserved for patients with equivocal CT findings and for patients in whom there is persistent clinical suspicion of hepatic metastases despite a negative CT examination. 相似文献
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134.
Vincent HS Low Laura E Heyneman David M Hough 《Journal of Medical Imaging and Radiation Oncology》1998,42(4):370-373
The cases of five patients with upper gastrointestinal barium examination findings suggestive of a post-bulbar duodenal tumour are presented. Further investigations failed to confirm evidence of a neoplasm, but instead identified post-bulbar duodenal ulceration or scarring. Possible causes for these findings, technical considerations for avoiding this pitfall, and the importance of appropriate further investigations are discussed. 相似文献
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136.
1病历报告患者邢××,女,28岁,住院号432259,于1998-08-10因右眼球破裂伤,球内容物脱出急诊入院.入院前1h患者搬运八宝粥易拉罐时,其中一听易拉罐盖突然爆炸击伤,当即感右眼视物不见、疼痛、流血、流泪伴恶心头痛.入院体查:右眼视力光感,... 相似文献
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138.
Mediastinal lymph node metastases from bronchogenic carcinoma: detection with MR imaging and CT 总被引:2,自引:0,他引:2
Poon PY; Bronskill MJ; Henkelman RM; Rideout DF; Shulman HS; Weisbrod GL; Steinhardt MI; Dunlap HJ; Ginsberg RJ; Feld R 《Radiology》1987,162(3):651-656
Magnetic resonance (MR) imaging and computed tomography (CT) were compared in a prospective study of 48 patients for the detection of metastatic mediastinal lymphadenopathy from bronchogenic carcinoma. The images were interpreted by three experienced radiologists using a five-point rating scale, enabling receiver operating characteristic (ROC) analysis. Imaging results were evaluated against "truth" data based on analysis of surgical specimens from mediastinoscopy and thoracotomy. All MR images were cardiac gated to reduce cardiac motion artifacts in the mediastinum. MR and CT both performed well, as indicated by similar areas under the ROC curves of 0.779 +/- 0.039 for MR imaging and 0.781 +/- 0.038 for CT scanning. No strong correlation between nodal size and metastatic involvement could be found for either MR or CT results. As long as nodal size remains the sole criterion in the detection of metastatic mediastinal lymphadenopathy, MR imaging is unlikely to enable better interpretations than CT scanning. 相似文献
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140.
HS Inalöz †‡ MMU Chowdhury † AG Knight† 《Journal of the European Academy of Dermatology and Venereology》2001,15(5):481-483
Lymphoepithelial neoplasms are biphasic tumours that contain both epithelial and lymphoid components. This heterogeneous group includes benign cutaneous lymphadenoma (CL), malignant lymphoepithelioma-like carcinoma of the skin and dermal thymus. We present two cases of CL in male subjects of 14 and 64 years of age. The latter man had a history of multiple basal cell carcinomas (BCCs) and solar keratoses. Histological sections of both tumours revealed similar features of an invasive non-ulcerated tumour with a mixed architecture of BCC and trichoepithelioma. Immunocytochemical examination revealed a biphasic epithelial tumour of follicular differentiation, possibly a variant of trichoepithelioma or a BCC. Within the epithelial islands there was a heavy infiltration that was confirmed as CD3-positive T cells and S-100-positive dendritic cells by immunocytochemistry. 相似文献