儿童后颅窝肿瘤的MRI影像特征  

MRI features of posterior fossa tumor in children

作　　者：赵萌 蒋敏波 陈相汛 陆超 胡毓华 唐文伟[3] ZHAO Meng JIANG Minbo CHEN Xiangxun et al(Department of Radiology, First Affiliated Hospital, Nanjing Medical University, Nanjing 210029, CHINA)

机构地区：[1]南京医科大学第一附属医院放射科,江苏省210029 [2]南京医科大学第一附属医院儿科,江苏省210029 [3]南京医科大学附属南京儿童医院放射科

出　　处：《江苏医药》2016年第20期2196-2199,F0003,共5页Jiangsu Medical Journal

基　　金：国家自然科学基金(81170487);江苏省妇幼保健重点学科建设项目(FXK201212)

摘　　要：目的探讨儿童后颅窝肿瘤的MRI影像特征。方法回顾性分析33例经病理学证实的后颅窝肿瘤患儿的MRI影像学表现。其中,髓母细胞瘤18例,毛细胞型星形细胞瘤8例,室管膜瘤3例,脉络丛乳头状癌、非典型畸胎瘤/横纹肌样瘤、皮样囊肿伴感染、脑膜瘤各1例。结果MRI检查显示,儿童后颅窝肿瘤好发于中线区。髓母细胞瘤以实性成分为主,增强扫描实性成分呈中度到明显强化;肿瘤实质扩散加权成像(DWI)序列呈高信号,表观扩散系数(ADC)图为低信号,ADC值为(0.68±0.05)×10-3 mm^2/s。毛细胞型星形细胞瘤实性成分DWI序列呈低信号,ADC图为高信号,ADC值为(1.80±0.03)×10^(-3) mm2/s。室管膜瘤为实性或囊实性肿块,增强后呈囊性改变,DWI序列及ADC图肿瘤实质信号强度介于髓母细胞瘤与毛细胞型星形细胞瘤之间。结论通过对MRI多序列扫描的综合分析,儿童后颅窝肿瘤术前一般可明确诊断。Objective To investigate the MRI features of posterior fossa tumor in children . Methods The MRI features of 33 children with posterior fossa tumor confirmed by histopathology were retrospectively analyzed ,which included medulloblastoma in 18 cases ,pilocytic astrocytoma in 8 cases ,ependymoma in 3 cases ,choroid plexus carcinoma in 1 case ,atypical teratoid/rhabdoid tumor in 1 case ,dermoid cyst with infection in 1 case ,and meningeal tumor in 1 case .Results MRI showed that posterior fossa tumor primarily occurred in the midline area .The solid component of medulloblastoma presented a moderate to strong enhancement ,and the tumor maintained a high signal intensity on diffusion weighted imaging（DWI） ,while the signal of ADC was low [（0.68 ± 0.05）× 10‐3 mm2/s] .On the contrary ,the solid component of pilocytic astrocytoma showed a low signal on DWI and a high signal on ADC[（1.80 ± 0.03）× 10‐3 mm2/s] .Moreover ,ependymoma demonstrated a solid or a cystic lesion with enhanced scan .The signal intensities of DWI and ADC were in somewhere between these of medulloblastomas and pilocytic astrocytomas .Conclusion Based on the comprehensive analysis of MRI multiple scanning ,the diagnosis of various kinds of posterior fossa tumor in children can be clearly defined .

关 键 词：后颅窝肿瘤 磁共振成像 儿童 

分 类 号：R445[医药卫生—影像医学与核医学]