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61.
The occurrence of a post-traumatic epidural hematoma in two patients with long-standing arrested hydrocephalus is reported. There was a relatively long interval between the head injury and the onset of symptoms. The large hematoma was accommodated by the decrease in size of the markedly dilated ventricles. This report stresses the possibility of the presence of an epidural hematoma in the management of head injury in patients with long-standing arrested hydrocephalus.  相似文献   
62.
Although the safety and efficacy of electroconvulsive therapy (ECT) is acknowledged by most, concern has repeatedly been expressed that the treatment may have some lasting effects on the brain. To study potential morphological changes, 22 patients with a history of ECT were submitted to a detailed clinical evaluation and a brain CT scan examination. Age- and sex-matched control subjects comprised a group of comparable patients, none of whom had received ECT, and a second control group of healthy volunteers. Patients had larger ventricle/brain ratios and cortical "atrophy" scores than normal controls, but no association was found between these radiological measures and a previous history of ECT. Hence, the present data are consistent with recent reports that affective disorders may be associated with enlarged brain ventricles, although the clinical significance of such findings remains unclear. In line with previous investigations age correlated significantly with cortical "atrophy" scores and ventricle/brain ratios for all subjects. Statistical tests of correlations between duration of illness, previous psychotropic drug exposure and CT scan appearances were mainly inconclusive.  相似文献   
63.
目的 :评价螺旋CT增强薄层扫描对周围型肺癌的诊断价值。方法 :2 7例周围型肺癌 ,对结节进行薄层扫描 ,然后以 3 5ml/s肘静脉注射碘对比剂 10 0ml后 40s、2min、5min、8min于相同几个中心层面进行增强扫描。分析结节的强化类型 ,描绘结节的时间 -密度曲线 ,计算结节的最大增强CT值。结果 :根据病灶的强化特点 ,我们将周围型肺癌强化类型分为二型 ,即均匀强化型和不均匀强化型。本组 2 7例肺癌 ,其中 17例 (6 3 % )在注射对比剂后 2min达到高峰 ,另外 10例 (37% )在注射对比剂后 5min达到峰值。本组病例中肺癌最大强化CT值 2 2~ 5 5HU(2 5 / 2 7) ,平均为 (4 1 8± 14 5 )HU。结论 :螺旋CT增强薄层扫描能准确判断病灶增强程度及方式 ,对提高周围型肺癌的诊断准确率有较大帮助。  相似文献   
64.
CT诊断输尿管梗阻病因分析   总被引:3,自引:0,他引:3  
韩敏  方佩君 《黑龙江医学》2001,25(9):643-645
目的 探讨CT诊断输尿管梗阻病因的价值。方法 本文收集 17例经多种泌尿系统的检查而未能确诊病因的资料。其中 ,12例经手术病理证实 ,2例经体外震波碎石治疗 ,3例经临床随访证实。结果 单纯性结石 5例 ,炎性狭窄 4例 ,乳头状移行细胞癌 2例 ,输尿管慢性炎症伴结石 1例 ,黄色肉芽肿性慢性肾盂肾炎伴结石 1例 ,右侧异位输尿管开口伴囊肿结石 1例 ,多囊肾伴左肾盂输尿管交界处狭窄 1例 ,左输尿管结核1例 ,乳房癌、直肠癌转移 /或侵犯输尿管各 1例。定位诊断率 10 0 % ,定性诊断率 88 2 4 %。结论 CT做为输尿管梗阻常规检查后的补充检查手段能有效提高病因诊断的正确率。  相似文献   
65.
Computed tomography (CT) scans are often used for postoperative imaging in orthopedics. In the presence of metallic hardware, artifacts are generated, which can hamper visualization of the CT images, and also render the study ineffective for 3-D printing. Various solutions are available to minimize metal artifacts, and radiologists can employ these before or after processing the CT study. However, the orthopedic surgeon may be faced with situations where the metal artifacts were not addressed. To counter such problems, we present three do-it-yourself (DIY) techniques that can be used to manage metal artifacts.  相似文献   
66.
During aging, changes in endosteal and periosteal boundaries of cortical bone occur that differ between men and women. We here develop a new procedure that uses high-resolution peripheral quantitative CT (HR-pQCT) imaging and 3D registration to identify such changes within the timescale of longitudinal studies. A first goal was to test the sensitivity of the approach. A second goal was to assess differences in periosteal/endosteal expansion over time between men and women. Rigid 3D registration was used to transform baseline and all follow-up (FU) images to a common reference configuration for which the region consisting of complete slices (largest common height) was determined. Periosteal and endosteal contours were transformed to the reference position to determine the net periosteal and endosteal expansion distances. To test the sensitivity, images from a short-term reproducibility study were used (15 female, aged 21 to 47 years, scanned three times). To test differences between men and women, images from a subset of the Geneva Retirees Cohort were used (248 female, 61 male, average age 65 years, 3.5 and 7 years FU). The sensitivity study indicated a least significant change for detecting periosteal/endosteal expansion of 41/31 microns for the radius and 17/26 microns for the tibia. Results of the cohort study showed significant net endosteal retraction only in females at the radius and tibia after 3.5 years (38.0 and 38.4 microns, respectively) that further increased at 7 years FU (70.4 and 70.8 microns, respectively). No significant net periosteal changes were found for males or females at 7 years. The results demonstrate that it is possible to measure changes in endosteal contours in longitudinal studies within several years. For the investigated cohort, significant endosteal retraction was found in females but not in males. Whether these changes in cortical geometry are related to fracture risk remains to be investigated in larger cohorts © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
67.
68.
目的:比较各种影像检查在胆道梗阻患者的诊断上的优劣。方法:分析89例年龄在12-75岁的胆道梗阻患者的CT、B超,胆道造影资料。结果:对胆管癌,胰头癌,炎性狭窄,肝癌,壶腹癌的诊断,胆道造影与病理的符合率较高,肿大淋巴结的诊断,CT与B超较胆道造影与病理的符合率高,对于梗阻部位,胆道造影,CT与手术的符合率较B超与手术符合率高。结论:胆道造影与CT对梗阻部位及原因的诊断准确率较高。B超的临床实用性较高。  相似文献   
69.
Twelve patients undergoing surgery between May 1995 and March 1999 for malignant tumours of the paranasal sinuses abutting or invading the orbital walls were studied for the need to remove orbital contents. Alt patients were evaluated clinically, radiologically (CT Scan) and per-operatively to delineate the extent of orbital invasion. Combined regimen (Surgery + Radiotherapy) were used in all patients. A biopsy from periorbita was taken when eye was spared. It was found that per-operative evaluation of the orbit is equally specific in comparision to clinical and CT Scan combined and eye may be preserved in selected patients with involvement of orbital periosteum provided there is no frank soft tissue mass in the orbit.  相似文献   
70.
Problem: There is a lack of clear criteria for the use of MR and CT in the diagnosis of head and neck cancer – some of it is even contradictory. The results of this study should lead to the establishment of more clear criteria. Patients: 165 patients suffering from head and neck tumors were subjected to a total of 463 CT and 197 MRI examinations. Results: The CT and MRI staging corresponded in 67% and 60% of the oropharynx tumors, respectively, with the clinical findings. In the case of oral cavity tumors, the clinical TNM stages were identical with CT and MRI results in 50% and 43% of cases, respectively. In the case of lymphatic node staging, the frequency of error was slightly higher using MRI, at 27%, compared with the CT rate of 22%. In the evaluation of cervical lymphatic nodes, CT proved to be more sensitive attaining 78% compared to the MRI rate of 69%. Conclusion: The results provide clear indications as to the MRI and CT examinations. Primary preoperative screening and post-therapeutic aftercare should be assessed using CT, as should lymphatic node diagnosis in the neck area. In the case of special problems such as, for example, the relevant bone and periostium infiltration, MR should be considered as a supplementary examination at a second stage.   相似文献   
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