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71.
作者通过对30例颅脑疾患冠状CT扫描资料进行研究,提出在一定情况下,在横断CT扫描的基础上,加用冠状CT扫描或冠矢重建图象,对病变的精确定位、病变的起源和发展方向以及病变与周围结构的关系等很有裨益。  相似文献   
72.
45 patients with spinocerebellar degeneration (SCD) underwent through quantitative investigation of the ventricular and cisternal systems by CT scanning and threshold vibrometry in the limbs to find out whether these parameters could be used for distinguishing mainly spinal from cerebellar forms or from olivopontoce-rebellar atrophy. The increase in the vibration sense threshold and the mild atrophy in the posterior cranial fossa proved typical of spinal forms and the reverse for cerebellar forms. In olivopontocerebellar atrophy enlargement of the cisterns and dilatation of the ventricles always exceeded 85% of normal values.
Sommario 45 pazienti affetti da degenerazione spinocerebellare (SCD) sono stati sottoposti ad uno studio approfondito di esplorazione quantitativa del sistema ventricolare e cisternale alla TAC e della soglia di percezione vibratoria agli arti per valutare la possibilità di distinguere con questi parametri le forme prevalentemente spinali da quelle cerebellari o delle atrofie olivopontocerebellari. L'aumento della soglia vibratoria e la modesta atrofia in fossa posteriore è risultata tipica delle forme spinali, mentre l'inverso si verifica per le forme cerebellari. Nelle atrofie olivopontocerebellari l'allargamento delle cisterne e la dilatazione dei ventricoli supera quasi sempre l'85% rispetto ai casi normali.
  相似文献   
73.
Summary A false-negative finding on initial CT is reported in a case of supratentorial glioma. This observation was peculiar because the first CT revealed a meningioma which might initially have been related to the clinical symptoms. The term false positive-false negative CT is proposed. The reasons for such CT failures are discussed. The accuracy of clues as to the localization of the glioma provided by EEG is emphasized.  相似文献   
74.
自发性颅内低压综合征的影像学特点   总被引:4,自引:0,他引:4  
自1938年Schaltenbrand第一次描述1例自发性颅内低压综合征病例以来,该病症逐渐为人们认识。颅内低压综合征的诊断主要根据临床有典型的体位性头痛症状(直立位出现或加重,平卧位减轻或消失),同时腰椎穿刺测脑脊液压力低于8kPa(60mmH2O)。自20世纪90年代以来,文献报道的本综合征神经影像学表现越来越多,并使其诊断发生了革命性的变化。本文将就其影像学特点及发生的病理生理机制进行简要介绍。1自发性颅内低压综合征影像学表现的病理生理基础腰椎穿刺脑脊液压力低于8kPa(60mmH2O)是诊断自发性颅内低压综合征的主要依据,脑脊液压力降低也一…  相似文献   
75.
Gross hemorrhage is the most serious complication of anticoagulant therapy. We report the discovery and treatment of a large pseudoaneurysm of the superior gluteal artery in one patient who had been receiving oral anticoagulant therapy. We diagnosed the pseudoaneurysm by contrast-enhanced computed tomography, and embolized the artery with stainless steel coils. The exact cause of the pseudoaneurysm remains unclear, however, minor trauma appears most likely.  相似文献   
76.
Bertalanffy  H.  Kretzschmar  H.  Gilsbach  J. M.  Ott  D.  Mohadjer  M. 《Acta neurochirurgica》1990,104(3-4):151-155
Summary This case report describes a patient presenting with symptoms of increased intracranial pressure, whose computerized tomographic (CT) scan was highly suggestive of a large low-grade glioma invading the basal ganglia. Magnetic resonance imaging (MRI) revealed a well-demarcated space-occupying mass of increased intensity in the left lateral ventricle and adjacent white matter. Following stereotactic biopsy, which yielded a homogeneous jelly-like material, the mass was removed microsurgically and was found to be most like a colloid cyst on histological examination. Discussion focusses on the clinical and differential diagnostic implications of this very unusual combination of findings.  相似文献   
77.
An advanced analysis of the mechanical properties of bone should include information about the microarchitecture of cancellous bone in addition to its density. It has recently been shown that high-resolution quantitative computed tomography and magnetic resonance imaging have the potential to assess such information in a noninvasive way in patients. Both techniques, however, lack sufficient spatial resolution to image the individual trabeculae with true precision. In this work, a new parameter, Ridge number density (RND), is introduced. RND is a measure for the trabecular number, which can be extracted directly from high-resolution three-dimensional (3D) images of patients. We applied the RND technique to a test group of nine healthy, postmenopausal women measured repetitively with a high-resolution 3D peripheral quantitative computed tomography (3D-pQCT) system with 165 × 165 × 165 μm3 voxel size. Simultaneously with the RND determination, the trabecular bone density (TBD) was also assessed in the same volume of interest. The examination site was the distal radius. The intersubject variability of the measured test group was 10.5% for RND and 26.3% for TBD. The root mean square error between first and second examinations (midterm reproducibility) was 1.6% and 1.1%, respectively. RND is determined independently from TBD and pertains to the structure of the cancellous bone. As such, it might add crucial information in cases where bone mass or bone density measurements alone give ambigous results.  相似文献   
78.
79.
颅脑转移瘤的CT和MRI研究   总被引:1,自引:0,他引:1  
134例颅脑转移瘤,CT增强薄层扫描88例,其中延迟扫描58例;薄层MRI 44例。114例(85%)有幕上转移,38例(28%)有幕下转移。73例(54%)多发,64例(46%)单发。增强MRI显示清晰和尚清晰者为42例(95%),增强后1~3min CT延迟扫描显示清晰和尚清晰者为55例(95%),延迟3min以上显示清晰和尚清晰为95%。可见,增强CT延迟扫描和大剂量增强CT对颅脑转移瘤的检出效果与增强MRI是相仿的。  相似文献   
80.
胸部气道的CT研究   总被引:1,自引:0,他引:1  
作者采用自己设计的两种扫描方法与常规扫描方法对照对67例患者的正常气道的CT表现进行分析,比较不同扫描方法在显示气道方面的优劣。结果显示:常规CT扫描方法能显示大部分支气管分枝,最远可分辨亚段支气管,但对右侧B4、B5,左侧B2、LB、B4、B5及两侧B7、B8显示差;扫描架向头侧倾斜25°能明显改善右侧B4、B5,左侧LB、B4、B5的显示情况。  相似文献   
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