脑发育性静脉异常的MR诊断

目的:评价MRI对脑发育性静脉异常(DVA)的诊断价值。方法:收集MR诊断为DVA的患者51例,均行MR平扫及增强检查,其中11例行磁敏感加权成像(SWI),回顾性分析其MR表现。结果:51例DVA中发生于额叶白质27例,顶叶白质9例,颞叶4例,基底节区2例,小脑半球9例;合并出血2例,均位于幕下;并发海绵状血管瘤2例。MR平扫显示病灶14例,其中表现为条状流空信号者10例,表现为T2WI放射状高信号者4例;MR增强检查显示所有病灶,表现为"海蛇头"样强化特征。11例行SWI者均能清晰显示病灶,表现为"海蛇头"样低信号影。结论:DVA多发生于幕上额顶叶白质及小脑半球,合并出血少见,可并发海绵状血管瘤。MR平扫难以显示细小病灶,MR增强检查是显示DVA的有效方法,SWI对小静脉病变较敏感,能取代MR增强检查用于发育性静脉异常的诊断和随访。

Value of MRI in the Diagnosis of Cerebral Developmental Venous Anomaly

Objective:To evaluate the value of MRI in the diagnosis of cerebral developmental venous anomaly(DVA).Methods:51 patients diagnosed as DVA based on MR imaging were collected.All patients underwent pre-and post-contrast MRI,11 of which also underwent susceptibility weighted imaging(SWI).The MRI manifestations were analyzed retrospectively.Results:Of the 51 cases with DVA,the locations were white matter of frontal lobes(27 lesions),white matter of parietal lobes(9 lesions),temporal lobes(4 lesions),basal ganglia(2 lesions)and cerebellar hemispheres(9 lesions).There was combination with cerebellar hemorrhage in 2 lesions.DVA associated with cavernous hemangioma were found in 2 cases.Only 14 lesions were detected on pre-contrast MRI,which demonstrated as linear flow void appearance in 10 cases and as radiated high signal intensity on T2WI in 4 cases.On contrast enhanced MR imaging,all the lesions showed typical "caput medusae"-like enhancement.Of the 11 cases underwent SWI,"caput medusae"-like low signal intensity was clearly assessed.Conclusion:The most common locations of DVAs are the white matter of frontal and parietal lobes and cerebellar hemispheres,complicated with hemorrhage was uncommon,associated with cavernous hemangioma might be revealed.Small DVAs might not be detected on pre-contrast MRI,but post-contrast MRI is an effective method to delineate the lesion.SWI is sensitive to small venous anomaly and can be a substitutive modality for contrast enhanced MR imaging in the diagnosis and follow-up of DVA.