鼻咽癌放疗后放射性脑干损伤的MRI表现

Magnetic resonance imaging manifestations of radiation-induced brainstem injury in patients with nasopharyngeal carcinoma after radiotherapy

目的分析鼻咽癌患者放疗后发生放射性脑干损伤的MRI表现特征。方法对37例鼻咽癌放疗后发生放射性脑干损伤患者的MRI资料进行复阅,对MRI检查序列包括T1WI、T2WI、FLAIR以及增强扫描序列进行分析,明确放射性脑干损伤的病变部位、范围、信号强度和增强后病灶强化等的形态。结果 37例放射性脑干损伤患者,病变位于脑桥19例,中脑1例,延髓3例,脑桥+中脑6例,脑桥+延髓5例,中脑+脑桥+延髓3例。病灶在MRI上T1WI表现为等信号或低信号,T2WI表现为高信号,FLAIR表现为低、高混杂信号,增强后无明显强化者9例,强化者28例。强化方式:均匀斑片状强化者12例、不均匀环形强化者16例。结论 MRI可以清晰地显示放射性脑干损伤的病灶,MRI对于诊断放射性脑干损伤有着重要价值,为临床治疗提供参考。

Objective To analyze the magnetic resonance imaging （MRI） manifestation characteristics of radiation-induced brainstem injury in patients with nasopharyngeal carcinoma （ NPC ） after radiotherapy. Methods Brain MRIs from 37 patients with NPC who developed radiation-induced brainstem injury after radiotherapy were reviewed. The study analyzed imaging se- quences included Tl-weighted image （T1WI）, T2-weighted image （T2WI）, fluid attenuated inversion recovery （FLAIR） and enhanced scanning imaging to define the site, range, signal strength and enhanced form of the lesions with radiation-induced brainstem injury. Results Among the 37 patients, 19 had lesions in pons; l in midbrain; 3 in medulla oblongata; 6 in pons and midbrain; 5 in pons and medulla oblongata; 3 in pons, midbrain and medulla oblongata. All lesions showed hypo- or iso-intense signal on TIWI, and hyper-intense signal on T2WI. With contrast enhanced scanning,9 cases did not show enhancement,28 ca- ses showed marked enhancement which included 12 cases with homogenous patchy enhancement and 16 cases with heterogene- Ous ringed and patchy enhancement. Conclusion MRI can clearly show the lesions of radiation-induced brainstem injury in NPC patients after radiotherapy, which is available for clinical diagnosis.