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111.
M. Bertolotto G. Cecchini C. Martinoli R. Perrone G. Garlaschi 《European radiology》1996,6(5):637-639
A case of primary non-Hodgkin's lymphoma (NHL) of the mandible with unusual radiographic presentation is reported. The panoramic radiography revealed diffuse widening of the right mandibular canal with ill-defined margins and absence of edge sclerosis. Computed tomography showed infiltration of the superior portion of the canal with involvement of the vestibular cortex of the bone and of the alveolar ridge.
Correspondence to: M. Bertolotto 相似文献
112.
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
113.
介绍自行研制的移动式护理机器人控制系统的功能和结构、开发过程中所面临的主要问题以及安全保护措施。所研制的机器人的控制系统具有高水平命令编译、机器人运动规划及环境设备控制功能。用户发出的任务指令由机器人的高水平集成控制系统分解为一系列低层的机器人部件控制命令或电器设备操作指令,然后由相应的控制器予以执行。 相似文献
114.
P. Mildenberger H. U. Kauczor Katja Ehrhard W. Schmiedt M. Thelen 《Der Radiologe》1997,37(11):883-890
Purpose: Prospective evaluation of the accuracy of CT angiography (CTA) with different postprocessing for extracranial carotid artery
in comparison with DSA.
Method: one hundred patients were studied with standarized CTA. For postprocessing, MPR, MIP, and 3D reconstruction based on segmentation
with upper and lower threshold were used. Intravascular density profiles were considered. All CTA studies were correlated
with intra-arterial angiography. The degree and classification of stenoses was determined using the guidelines established
by the NASCET collaborators.
Results: Measurement of stenosis was possible by MPR in 82.5 %, by MIP in 85 %, and 3D in 100 %. Correct classification was found
in 65.5 % for MPR, 66 % for MIP and 88.5 % for 3D. The sensitivity for severe stenoses was 74 % for MPR, 82 % for MIP, and
93 % for 3D. The specificity of these methods was 98 %, 96 %, and 97 %, respectively. All carotid occlusions were correctly
identified, no carotid artery was wrongly classified as occluded.
Conclusions: CT angiography allows reliable examinations in carotid artery stenoses and occlusions. 3D reconstruction based on threshold
segmentation is superior to MPR and MIP. In some circumstances, e.g., carotid occlusion, further investigation by invasive
procedures is not necessary.
相似文献
115.
116.
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
117.
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
118.
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
119.
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
120.
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