摘要
目的髓母细胞瘤是儿童常见的恶性肿瘤,发病率占后颅凹肿瘤的30%~40%。文中通过回顾性分析经手术确诊病例的MRI表现,探讨儿童髓母细胞瘤(medulloblastoma,MB)的MRI表现特点。方法收集经手术证实的13例MB,均行常规MRI平扫与增强扫描,并行弥散加权成像(diffusion weight imaging,DWI)与磁共振波谱成像(magnetic resonance spectroscopy,MRS)扫描。结果肿块均位于小脑蚓部,肿瘤内发生囊变6例。MRI扫描T1WI呈等或稍低信号,T2WI呈略高信号,增强扫描呈中等或明显强化,4例沿脑脊液播散。肿瘤实性部分DWI呈略高信号,表面扩散系数(apparent diffusioncoefficient,ADC)图呈略低信号,坏死囊变部分与脑脊液信号相仿。MRS显示胆碱(Cho)峰明显增高。结论 MRI能提供肿瘤浸润的范围、继发改变及其与周围组织的关系,还能够做出明确的定位与定性诊断。MRI还对MB沿脑脊液种植转移具有重要的诊断价值。常规MRI结合DWI、MRS对髓母细胞瘤的诊断和鉴别诊断有重要价值。
Objective Medulloblastoma(MB) is a malignancy commonly seen in children,accounting for 30%-40% of postcranial fossa tumors.The aim of this study was to investigate the MRI manifestations of pediatric medulloblastoma.Methods This study included 13 cases of medulloblastoma confirmed by surgery and pathology.All the patients underwent plain and enhanced MRI,diffusion weighted imaging(DWI) and MR spectroscopy(MRS).Results All the tumors were located at cerebellar inferior vermis,6 with cystic component.MRI displayed low-or equal-intensity signals on T1WI and slightly higher-intensity signals on T2WI.Contrast administration revealed middle or marked enhancement,and metastasis along the cerebrospinal fluid in 4 cases.The solid portion of the tumor gave slightly higher signals on DWI and slightly lower signals on the apparent diffusion coefficient map.The signals of necrosis and cystic lesions were similar to those of the cerebrospinal fluid.MRS showed elevated choline peaks in all the cases.Conclusion MRI can not only provide information on the extent of tumor invasion,secondary changes and relation with surrounding structures,but also determine the tumor location.Conventional MRI combined with DWI and MRS plays an important role in the diagnosis and differential diagnosis of medulloblastoma.
出处
《医学研究生学报》
CAS
2011年第6期590-592,共3页
Journal of Medical Postgraduates
基金
南京医科大学校基金面上项目(09NMUM027)
关键词
髓母细胞瘤
MRI
弥散加权成像
磁共振波谱成像
Medulloblastoma
Magnetic resonance imaging
Diffusion weighted imaging
Magnetic resonance spectroscopy
