DWI技术在鼻咽癌早期放射性脑损伤中的应用价值

Application Value of DWI in Early Radiation-induced Brain Injury after Radiotherapy for Nasopharyngeal Carcinoma

目的探讨磁共振扩散加权成像(DWI)在鼻咽癌早期放射性脑损伤中的应用价值。方法选择我院经病理证实的30例鼻咽癌患者,分别于放疗前、首次放疗后3 d、放疗结束时、放疗后3、6、12个月时进行颅脑常规MRI平扫及DWI检查,分析不同时期的表观弥散系数(ADC)。同期选择30例健康志愿者作为对照组,测量其ADC值并与鼻咽癌组进行对比。结果志愿者与放疗前鼻咽癌患者双侧颞叶白质的ADC值无统计学差异;鼻咽癌患者首次放疗后3 d、放疗结束时及放疗结束后3个月,与放疗前ADC值差异有统计学意义(P<0.05);放疗结束后6、12个月与放疗前ADC值差异无统计学意义。结论 DWI成像技术是检测放疗后早期放射性脑损伤较理想的手段和方法。

Objective To evaluate the significance of clinical application of diffusion weighted imaging（DWI） in the diagnosis of radiation-induced brain injury after radiotherapy for nasopharyngeal carcinoma. Methods 30 patients with nasopharyngeal carcinoma underwent MRI and DWI examination at different points： before the radiation therapy, 3 d after radiotherapy for the first time, immediately after the radiotherapy, and 3 months, 6 months, and 12 months after the radiotherapy. The ADC values in different periods were analyzed. Meanwhile, 30 healthy volunteers were also studied as the control group. Results The ADC values of bilateral temporal lobe in volunteers and nasopharyngeal carcinoma patients before radiotherapy had no statistical difference.The ADC value checked three days after radiotherapy for the first time and the ADC value checked at the end of the radiotherapy as well as the value checked three months after the radiotherapy were lower than the ADC values in pre-radiotherapy patients（P〈0.05）. The ADC values checked at 6 and 12 months after the radiotherapy showed no difference from the ADC value in pre-radiotherapy period. Conclusion DWI is an ideal mean to detect early radiation-induced brain injury.