桥小脑角区肿块性病变的MRI表现及其分析  

Analysis of MRI findings of cerebellopontine angle mass

作　　者：万水治 王中秋[2] 

机构地区：[1]解放军第八六医院医学影像科,当涂243100 [2]南京军区南京总医院医学影像科,南京210002

出　　处：《医学研究生学报》2010年第3期267-270,共4页Journal of Medical Postgraduates

基　　金：江苏省自然科学基金(BK2008325);南京军区医药卫生科研基金(08MA087)

摘　　要：目的MRI的应用对桥小脑角区肿块性病变的诊断具有重要作用。文中分析桥小脑角区肿块性病变的MRI表现,以提高桥小脑角区病变的诊断准确率,为临床治疗方案的制定提供有价值的影像信息。方法选取42例桥小脑角区肿块性病变,行MRI检查和手术病理证实,对该组病变的MRI表现和病理结果进行回顾性对照分析。结果42例桥小脑角区肿瘤中,听神经瘤22例,其中16例表现为实性肿块,6例为囊实性病变,瘤体在T1WI等或稍低信号,在T2WI呈等高混杂信号,囊性部分不强化,实性部分强化;脑膜瘤7例,其中6例表现典型,瘤体在T1WI和T2WI均呈等信号,肿瘤明显均匀强化,5例可见"脑膜尾征";蛛网膜囊肿2例,表现为水样信号,病变不强化;表皮样囊肿5例也表现为水样信号,但在DWI上呈高信号,增强扫描无强化。其他病变如髓母细胞瘤2例,海绵状血管瘤、星形细胞瘤、室管膜瘤、内淋巴囊乳头状肿瘤各1例,MRI表现各有特点。MRI的定位准确率95.2%,正确诊断率为88%。结论MRI对桥小脑角区肿块性病变定位、诊断准确率高,但对该部位不典型病变存在误诊现象,应注意鉴别。Objective MRI has important value in the diagnosis of brain diseases.This study aimed to analyze the MRI findings of cerebellopontine angle mass（CPAM）,in an attempt to improve the diagnostic accuracy of MRI for this lesion and provide valuable imaging information for clinical treatment.Methods Forty-two CPAM patients underwent MRI and post-operative pathological examination.The MRI findings and pathologic results were comparatively analyzed.Results Of the 42 cases,22 were acoustic neuroma,including 16 cases of solid mass and 6 cases of cyst solid masses,with iso-or slightly low-intensity MRI signals on T1WI,iso-or slightly high-intensity signals on T2WI,middle enhancement of the solid part and no enhancement of the cyst part of the tumors.Seven of the cases were meningioma,with iso-intensity signals on T1WI and T2WI,obvious enhancement of the tumors,and meninges tail signs in 5 cases.Two of the cases were arachnoid cyst,with cereberal spinal fluid signals and no enhancement of the tumor.Five of the cases were epidermoid cyst,with hypo-intensity on T1WI,hyper-intensity on T2WI and DWI,and no enhancement on Gd-DTPA enhanced T1WI.The others included 2 cases of medulloblastoma,1 cavernous hemangioma,1 astrocytoma,1 ependymoma,and 1 endolymphytic sac tumor,with varied MR signal intensities and appearances.The rate of accurate location was 95.2%,that of correct diagnosis was 88%,and that of misdiagnosis was 12%.Conclusion MRI has high rates of accurate location and correct diagnosis for CPAM.However,some atypical cases call for careful differential diagnosis.

关 键 词：桥小脑角 脑 肿块 MRI 

分 类 号：R816.1[医药卫生—放射医学]