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991.
992.
Three patients with transient episodes of hypotension following blunt abdominal trauma incurred in motor vehicle accidents were examined by computed tomography within 6 hours of injury. The examinations were done using a contrast material injection technique that ordinarily leads to greater splenic than hepatic attenuation. None of the patients had splenic injury evident on autopsy, surgery, or clinical follow-up study (one case each), nor did they have other characteristic features of splenic infarction. However, in each case the spleen was less enhanced than the liver, leading to an erroneous impression in one patient that the splenic artery had been disrupted. Physiologic studies have shown that splenic perfusion decreases with sympathetic stimulation; this may have been the cause of the diminished enhancement. Decreased splenic enhancement should be interpreted cautiously in traumatized hypotensive patients. 相似文献
993.
994.
The criteria for a diagnosis of loosening or infection of hip arthroplasties on arthrographic study were further refined by a retrospective review of 178 arthrograms representing 170 patients. The 97 arthroplasties that were surgically evaluated form the basis of this report. With the refined criteria, subtraction arthrography had a sensitivity of 96% and specificity of 92% for demonstrating loosening of the femoral component and a sensitivity of 97% and a specificity of 68% for demonstrating loosening of the acetabular component. Pseudocapsule size and the presence of bursae were important factors influencing arthrographic interpretation. Arthrographic findings of pseudocapsule irregularity and the presence of nonbursal cavities were suggestive of infection but were not sensitive or specific. Laboratory evaluation of aspirated material was a more reliable predictor of infection, although its sensitivity was only 71%. 相似文献
995.
Phantoms were used to compare imaging of various masses in the glandular region for two types of breasts. In one type, normal glandular tissue contains no fat clumps; in the other type, randomly distributed spherical fat clumps exist. The size distribution and number of fat clumps per unit volume in the phantoms represented those found in actual normal glandular tissue. For a 5-cm path length between the scanning window of the phantom and the centers of the masses, the presence of the fat clumps caused distortions and deviations of the beam, resulting in image distortion. This degradation was reduced when successive slabs of the material containing the fat clumps were removed. Image degradation appeared to be less severe when a 2.25 (rather than a 3.5) MHz transducer was used. The results show that the thickness of tissue containing fat clumps between the scanning transducer and a mass plays a role in the detectability of masses and diagnostic usefulness of the image of a breast. This suggests that imaging of the breast in the compressed configuration should be performed regardless of whether the freely suspended breast is imaged. Also, transducers of lower nominal frequency may have an important role in breast imaging. 相似文献
996.
Pitfall in MR imaging of lymphadenopathy after lymphangiography 总被引:3,自引:0,他引:3
In two patients examined with magnetic resonance (MR) imaging after lymphangiography, opacified pelvic lymph nodes could not be distinguished from subcutaneous or retroperitoneal fat because of the short T1 and long T2 relaxation times of lymphangiographic contrast media. Opacified nodes removed from one patient had relaxation times similar to those of fat. Thus, assessment of lymphadenopathy with MR imaging should be performed before lymphangiography to obviate this potential pitfall. 相似文献
997.
Telephone transfer of nuclear cardiology studies 总被引:1,自引:0,他引:1
Royal HD; Parker JA; Mandell CH; Uren RF; Chambers HM; Jansons D; Hyman RM; Kolodny GM 《Radiology》1983,147(2):590-591
998.
Purpose: Previous studies have shown that physicians often have poor knowledge of the medical restriction on fitness to drive, or submit poor quality medical reports. To determine the reliability of physicians'' reports on fitness to drive, the medical data provided on the standard medical fitness form was compared with the additional data collected on repeated assessment. Methods: A random sample of 100 applicants for a driver''s licence aged more than 49 years who submitted the standard medical form were asked to provide, from their regular family doctor, confirmation of their health status and/or additional medical data in order to make a re-evaluation. Results: The rate of rejection for a licence for medical reasons was 3% on the basis of the standard evaluation and 17% on the basis of the re-evaluation (p<0.001). Conclusion: This study shows that the random evaluation of physician assessments of applicants for a driver''s licence increases the detection rate of medical problems that can affect fitness to drive. The alarming difference in the rate of rejection between the two assessments may reflect a lackadaisical attitude of medical professionals toward the licence assessment procedure and/or physician unawareness of the medical restrictions on fitness to drive. Results of this study suggest that this subject must be included in medical education programmes. 相似文献
999.
1000.
Carien HG Beurskens Caro JT van Uden Luc JA Strobbe Rob AB Oostendorp Theo Wobbes 《BMC cancer》2007,7(1):166