磁共振扩散加权成像在鼻咽癌放疗后局部复发诊断中的应用

目的探讨磁共振（Urn）扩散加权成像（DWI）在诊断鼻咽癌放疗后局部复发诊断中的价值。方法收集经病理证实的鼻咽癌放疗后复发患者36例和放疗后坏死患者24例，均接受常规MR检查和DWI检查，分析DWI表现，并对两组患者的表观扩散系数（ADC）进行比较。结果放疗后复发组在DWI多表现为高信号，而放疗后坏死组多表现为低信号；放疗后复发组和坏死组ADC平均值分别为（0．87±0．13）×10^-3mm^2／s和（1．12±0．18）×10^-3mm^2／s，差异有统计学意义（t=3．782，P〈0．001）。结论DWI对鼻咽癌放疗后局部复发的诊断与鉴别诊断具有重要价值，可作为常规MRI序列的重要补充。

Application of diffusion weighted imaging in diagnosing recurrence of nasopharyngeal carcinoma after radiotherapy

Objective To explore the value of the diffusion weighted rence of nasopharyngeal carcinoma （NPC） after radiotherapy. Methods imaging （ DWI） in the diagnosis of recur- 36 patients with recurrence of NPC after radiotherapy and 24 patients with necrosis of NPC after radiotherapy were enrolled. All patients were confirmed pathologically, and received routine MRI and DWI. The DWI and apparent diffusion coefficient（ADC） of lesions were analyzed. Results Most of the recurrence group showed low singal, but the necrosis group showed high sig- nal. The mean ADC values in the recurrence group and the necrosis group were （0.87±0.13）×10^-3mm^2/sand （ 1.12±0.13）×10^-3mm^2/s respectively, the difference of which was also statistically significant （ t = 3.782, P 〈 0. 001 ）. Conclusion DWI is important in diagnosis and differentil diagnosis of recurrence of NPC after radio- therapy, which can be used as important supplementary to routine MRI.