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131.
Thirty-three patients with a variety of disorders of the thoracic aorta (aneurysm, dissection, Marfan syndrome, coarctation/pseudocoarctation, L-transposition, and Takayasu disease) were evaluated with magnetic resonance (MR) imaging. MR imaging delineated the presence and extent of thoracic aortic aneurysms and showed the relationship of the aneurysm to arch vessels; it also demonstrated intimal flaps and individual lumina in types A and B aortic dissection. Dilation of the ascending aorta in Marfan syndrome and focal narrowing of the aorta in coarctation were well visualized. The anteroposterior and side-to-side relationships of the aorta and pulmonary artery in L-transposition were demonstrated, as were aortic wall thickening and branch vessel narrowing in Takayasu arteritis. Initial experience suggests that MR imaging may provide a noninvasive method for evaluating thoracic aortic disease. Limitations include inferior spatial resolution, occasional difficulty in imaging the entire region of interest in one section, lack of signal from calcifications, and inability to monitor critically ill patients. 相似文献
132.
Background
While medicine in general is becoming more female-dominated, women are still under-represented in surgery. Opinion is divided as to whether this is due to lifestyle considerations, disinterest or perceived discrimination. It is not clear at what stage these careers decisions are made. 相似文献133.
Spontaneous resolution of cholelithiasis in infants 总被引:1,自引:0,他引:1
Follow-up sonographic studies of five infants whose initial sonograms had displayed evidence for the diagnosis of cholelithiasis demonstrated spontaneous resolution of the gallbladder defects. These defects may have been caused by tumefactive sludge with acoustic shadowing. Whether sludge or gallstones are being imaged, in the absence of other clinical or imaging evidence of biliary tract disease, conservative (i.e., nonsurgical) management and serial sonograms are recommended. 相似文献
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137.
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
138.
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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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