鼻咽癌放疗后放射性脑病的MRI诊断分析

MRI Diagnosis and Analysis of Radiation Encephalopathy after Radiotherapy for Nasopharyngeal Carcinoma

目的探讨鼻咽癌放射治疗后放射性脑病(REP)的MRI特征性影像表现,并分析其诊断价值。方法对38例鼻咽癌放疗后REP的MRI资料进行回顾性分析。结果 38例REP中共检出53个病灶。92.5%(49/53)发生在颞叶,3.8%发生在脑干,额叶及小脑各占1.9%。MRI特征性影像表现为,有86.9%病灶T1WI呈低信号,T2WI呈高信号,增强后呈花环状、不规则斑片状强化。10.5%病灶T1、T2皆呈等信号,增强后呈结节状强化。1例为囊性病灶,信号程度同脑脊液相仿,增强后未见明显强化。MRI定期复查能够及时发现REP随病程进展表现不同,其病灶的大小、信号变化均有不同。结论鼻咽癌放射治疗后放射性脑病的MRI表现有一定的影像特征,MRI动态影像观察对病变的早期发现、进展及预后判断有重要价值,同时对鉴别诊断也有很大帮助。

Objective To observe the MRI characteristic imaging findings and diagnostic value of the radiation encephalopathy（REP） after radiotherapy for nasopharyngeal carcinoma.Methods MRI manifestations of 38 patients with diagnosis of radiation encephalopathy were retrospectively reviewed.Results In 38 cases of REP of detection of 53 lesions.92.5%（49/53） occurs in the temporal lobe,3.8% occurred in the brainstem,frontal and cerebellar each accounted for 1.9%.MRI characteristic imaging findings for 86.9% lesions showed low signal on T1WI and showed high signal intensity on T2WI,enhanced in flower ring,irregular and patchy enhancement.10.5% lesions on Tl and T2 showed a signal,enhanced nodular enhancement.In 1 cases,cystic lesions,signal with cerebrospinal fluid similar,no obvious enhancement after enhancement.MRI periodic review can be found in a timely manner REP with disease progression vary,the size of the lesion,signal changes are different.Conclusion MRI of radiation encephalopathy after radiotherapy in nasopharyngeal carcinoma showed a certain image features,MRI dynamic imaging observation of the lesions are detected early,progression and prognostic value,while the differential diagnosis are also of great help.