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51.
Richard Tello Reginald F. Munden Stuart Hooton Kris Kandarpa Robert PugatchAuthor vitae 《Computerized medical imaging and graphics》1998,22(6):267-452
Introduction: Features of spiral CT (SCT) — fast scanning, dynamic injection of contrast allowing optimal vessel opacification, and supplemental multiplanar imaging — promises to provide increased accuracy in the diagnosis of acute and non acute thoracic vascular disease. Recent work demonstrating the cost effective triage of hemodynamically stable patients after blunt chest trauma for angiography based on dynamic CT findings has prompted an investigation into the accuracy of SCT in this clinical setting. Methods: A retrospective review of all patients seen in the emergency department over the period of one year for aortic, thoracic, or blunt chest trauma evaluation was performed (74 patients) and all SCT scans available were reviewed and data reformatted for optimal delineation of pathology using maximum intensity projection and multiplanar reformation. The accuracy and predictive positive and negative values of SCT were calculated with respect to angiography, surgical, and/or clinical follow up evaluation. Results: Twenty three (31%) patients went directly to angiography owing to mediastinal widening on chest film and hemodynamic instability, of which four were positive and required emergent surgery. Seven hemodynamically stable patients (9%) had noncontrast SCT owing to mediastinal widening on chest film, all of which had angiography with none having great vessel trauma. Fourty four hemodynamically stable patients (60%) had contrast enhanced SCT (ceSCT), of which five (11%) were abnormal and underwent angiography, four of these were positive for aortic damage, one for a subclavian artery laceration. Of the remaining 39 patients who had normal ceSCT; five had angiography, all of which were normal. Of the remaining 34 patients that had normal ceSCT none had adverse outcome on clinical follow-up, minimum of 12 months. Conclusion: The predictive positive value for aortic trauma of ceSCT in blunt trauma is 80%, with a predictive negative value of 100%, indicating that it is feasible for SCT to be a first line exam in blunt chest trauma in the future. 相似文献
52.
53.
S. Takahashi K. Ishii K. Matsumoto S. Higano T. Ishibashi M. Suzuki K. Sakamoto 《Neuroradiology》1994,36(5):337-339
We reviewed 12 cases of infarcts in the territory of the anterior choroidal artery (AChA) on CT and/or MRI. In each case vascular occlusion in the region was verified angiographically. Although the extent of the lesion on CT/MR images was variable, all were located on the axial images within an arcuate zone between the striatium anterolaterally and the thalamus posteromedially. The distribution of the lesions on mutiplanar MRI conformed well to the territory of the AChA demonstrated microangiographically. The variability of the extent of the infarcts may be explained by variations in the degree of occlusive changes in the AChA or the development of collateral circulation through anastomoses between the AChA and the posterior communicating and posterior cerebral arteries. The extent of the lesion appeared to be closely related to the degree of neurological deficit. 相似文献
54.
目的:分析立体定向X-刀放射治疗颅内肿瘤后的近期疗效,并进行阶段性工作总结。材料和方法:53例不同类型脑瘤患者,以CT、MR、DSA图像资料作为定位依据,用德国Brain LAB治疗计划系统设计三维优化方案,西门子MD-2型直线加速器旋转照射。结果:53例患者经X-刀治疗后,近期均取得了满意效果,诸如以卡氏评分法评价,临床症状有所改善;以CT增强扫描复查观察,肿瘤大小趋于缩小或消失。结论:立体定向放射治疗后的追踪观察表明,只要严格掌握适应症,精确定位,精确计划,精心治疗,X-刀是一种安全、有效、无痛苦的治疗脑肿瘤的方法。它可起到改善临床症状,提高患者生活质量,延长生存期限的作用。 相似文献
55.
R. Raininko I. Elovaara E. Poutiainen A. Virta L. Valanne M. Haltia J. Lhdevirta 《European journal of neurology》1997,4(2):143-151
The course of the organic brain disease caused by human immunodeficency virus (HIV-1) was evaluated in a follow-up study. The primary material included 200 consecutive HIV-1 infected persons. Sixty-one subjects, in whom other brain-affecting factors were excluded, consented to the follow-up. They underwent 278 radiologic examinations: computed tomography, magnetic resonance imaging, or a combination of both (mean 4.6 examinations/subject). Clinical neurologic status and, in 40 subjects, cognitive performance were repeatedly evaluated. Sixteen subjects were followed up until death and 11 of them were autopsied. Median follow-up time was 27 mo (range 2.5–66 mo). The most common radiologic finding was atrophy, found in 19 subjects at study entry and developing in 10 subjects during the study. Twenty-four subjects (39%) showed the development and/or progression of atrophy. Atrophic changes progressed most rapidly in acquired immunodeficiency syndrome (AIDS), but mild developing/progressive atrophy was found even in 33% of asymptomatic or neurologically intact subjects. Cognitive and radiologic worsening were simultaneous in 6/7 subjects with declining neuropsychologic test performance. Signal intensity changes including HIV-1 leukoencephalopathy appeared in AIDS patients with clear cognitive decline. 相似文献
56.
Intracranial alveolar echinococcosis: CT and MRI 总被引:1,自引:0,他引:1
A. H. Bensaid J. L. Dietemann M. M. Filippi de la Palavesa A. Klinkert B. Kastler A. Gangi G. Jacquet F. Cattin 《Neuroradiology》1994,36(4):289-291
Intracranial alveolar echinococcosis is uncommon. We report a patient with right frontal lobe and palpebral lesions secondary to a primary hepatic focus with secondary lesion in the lung. The intracranial and palpebral cystic masses were totally removed and both proved to be alveolar hydatid cysts. An unusual feature in this case is CT and MRI demonstration of dural and bony extension. 相似文献
57.
Patrick M. Rao M.D. James T. Rhea M.D. Robert A. Novelline M.D. 《Emergency radiology》1997,4(5):268-275
This article reviews a focused helical appendiceal computed tomographic technique and discusses an approach to appendiceal computed tomographic interpretation. 相似文献
58.
We describe characteristic findings in a patient with Marchiafava-Bignami disease who was serially imaged with CT and MR. Involvement of the entire corpus callosum was visualized with both types of imaging. Following administration of gadolinium-DTPA, the lesion was clearly enhanced in the subacute stage.
Correspondence to: S. Otake 相似文献
59.
对126列原发性肝癌与37例转移性肝癌介入治疗前均进行了B超、CT与数字减影血管造影(DSA)检查。DSA显示原发性肝癌多数血供丰富,而转移性肝癌以少血供者为主;CT显示小病灶的敏感性稍差,病灶的密度和均匀性与血供多少有一定关系,但特异性不高,而病灶的增强次应与血供关系密切,多血供者中95%有显示的增强效应,少血供者仅占4.7%;B超所示病灶的回声高低与血供亦有一定关系,但特异性稍差。结果表明,D 相似文献
60.
多层面CT重建诊断中央大气道良性病变 总被引:7,自引:0,他引:7
目的 :分析多层面CT三维重建诊断中央大气道良性病变的价值。材料和方法 :用多层面CT对 3 5例中央气道良性病变 (解剖性异常 5例 ,炎症性病变 18例及其它 12例 )扫描 ,并全部完成三维表面遮盖显示、容积显示和仿真内窥镜检查。所有病例第一次读片时仅有横断面图像 ,第二次读片时增加重建图像。结果 :三维重建帮助 4例横断面漏误诊的解剖性异常获得确诊 ,16例炎症性病变进一步详细显示 ,2例气管支气管裂伤明确范围和程度 ;虚拟内窥镜帮助 5例横断面上不能确诊的痰液获得确诊。结论 :CT三维重建可用于解剖性异常和痰液的诊断 ,对其它良性疾病主要是对病变的另一种形式的进一步显示。 相似文献