脑磁共振静脉成像

目的：磁共振静脉成像(MRV)已被广泛应用于颅内静脉系统检查，特别是用来评价静脉窦血栓形成。本研究的目的是评价脑MRV描述正常颅内静脉系统解剖和变异的作用，评价它在诊断硬脑膜窦血栓形成过程中潜在的误诊因素。材料和方法：对79例常规磁共振表现正常的MRV图像进行分析，观察硬脑膜窦和主要静脉的表现和缺失情况。其中7例志愿者接受了MRV和3DPCMRA两种方法检查。结果：上矢状窦、直窦、Galen静脉和大脑内静脉显示率为100％，枕窦显示率为10％，基底静脉显示率为92％。横窦血流间隙显示率约为34％，均出现在非优势侧横窦，优势侧横窦没有出现流动间隙。结论：MRV是有效的评价颅内静脉系统方法。常规MR表现正常者中有34％可以发现横窦流动间隙，这些流动间隙不应被误诊为静脉窦血栓形成。

Cerebral MR Venography

MR venography has been extensively used to examine the intracranial veno us system,particularly in the evaluation of dural sinus thrombosis.The abstract o f this study was to evaluate the usefulness of MR venography in the depiction of the normal intracranial venous anatomy and its variants,and to assess its poten tial pitfalls in the diagnosis of dural venous sinus thrombosis.Materials and Me thods:Cerebral MR venograms obtained in 79 persons with normal MR imaging studie s were reviewed to determine the presence or absence of the dural sinuses and ma jor intracranial veins,7 volunteers of them were examined with both MRV and 3D P C MRA method.Results:Systematic review of the 79 cases revealed that the superio r sagittal sinus,the straight sinus,the vein of Galen and internal cerebral vein s were seen in every venogram.The occipital sinus was seen in only 10% of the c ases.The basal veins of Rosenthal were present in 92%.Transverse sinus flow gap s were observed in 34% of the cases occurring all in the nondominant transverse sinus.No flow gaps occurred in the dominant transverse sinuses.Conclusion:MRV i s an effective method to examine the intracranial venous system.Transverse sinus flow gaps can be observed in as many as 34% of patients with normal MR imaging findings,these gaps should not be mistaken for dural sinus thrombosis.