对15例放射性脑损伤MRI及MRS征象的探讨

目的:总结放射性脑损伤MRI与MRS表现,提高其影像诊断准确率。材料与方法:总结15例放射性脑损伤病例MRI表现(均经病理/随访证实),观察并比较病变部位、范围、增强表现及MRS分析结果。结果:本组病例放射性脑损伤病灶主要位于颞叶、脑干及小脑照射野白质内,多呈不规则花环样或结节样强化。3例MRS均显示Cho及NAA下降。放射性脑损伤MRI特点:有明确放疗史,神经系统症状于放疗后一定时期出现,定位与放射野吻合,多位于白质;无恶液质表现;有水肿及占位效应,MRS分析结果符合。结论:根据磁共振影像表现及MRS结果,结合放疗病史,可诊断多数放射性脑损伤;但不典型者仍应与肿瘤复发及脓肿等鉴别。

Investigate to MRI and MRS in 15 brain radiation injury cases

Objective: To summarize the MRI and MRS signs of brain radiation injury and improve the diagnostic accuracy. Materials and Methods: MRI manifestations of 15 brain radiation injury cases(proved by pathology follow-up) were analysed retrospectively, location, extent, signal and MRS result were observed. Result: The lesions preponderately located in the white matter of temporal lobe, brain stem and cerebellum, with irregular rim nodular enhancement. All of the 3 MRS showed declined Cho and NAA peak. The MRI signs of brain radiation injury include: definite history of brain radiation therapy, neurologic symptoms emerged after certain period of treatment, the location of lesion coincided with the radiation field, mainly located in white matter, with edema and mass effect, consistent with the MRS result, no dyscrasia. Conclusion: According to the typical MRI and MRS result, and the radiation therapy history, most of brain radiation injury cases can be diagnosed. But few atypical cases should be discriminated with recurrent of tumor or abscesses.