桥小脑角区髓母细胞瘤的 MRI 表现

目的：分析桥小脑角区(CPA)髓母细胞瘤的 MRI 特点,提高该病的诊断率。方法回顾性分析5例经手术病理证实的发生于 CPA 髓母细胞瘤的 MRI 表现特点及病理特征。结果5例髓母细胞瘤中4例见囊变,且均位于肿瘤的边缘,1例为完全实性肿块。肿瘤实性部分 T1 WI 呈低、稍低信号,T2 WI 呈稍高或高信号为主混杂信号。2例行 DWI 扫描呈高信号。增强后强化程度多样。5例肿瘤均引起桥脑及四脑室受压,2例邻近基底脑膜强化,2例出现瘤周水肿。结论MRI 可显示 CPA 髓母细胞瘤肿瘤的范围、继发改变及与周围组织的关系。

MR imaging characteristics of cerebellopontine angle medulloblastoma

Objective To analyze the MRI features of cerebellopontine angle(CPA)medulloblastoma and increase the rate of diag-nosis of this disease.Methods MRI features in five patients with pathologically proven CPA medulloblastoma were retrospectively reviewed.Results In all patients,masses were predominantly solid.Some cystic or necrotic components were demonstrated in four tumors,and the cystic components were on the edge of the tumors.The other one case was totally solid tumor.The solid component of five tumors were hypointense on T1-weighted imaging.Five tumors were mild and mixed hyperintense on T2-weighted imaging.In two tumors,there were focal areas of hyperintensity on DWI.The pons and fourth ventricle were compressed in all patients.Basilar meningeal enhancements were found in two patients.Two tumors were associated with peritumoral and parenchymal edema.Conclusion MRI can provide the informations of extent of invasion,secondary changes and relation with surrounding structures of medulloblastoma.