目的 分析口咽癌患者术后精确 放疗应用磁共振成像(MRI)和18氟-脱氧 葡萄糖正电子发射计算机体层成像(18FDG PET-CT)检查的临床价值。方法 回顾性分 析我院进行精确放疗的49例口咽癌患者的 MRI及18FDG PET-CT检查资料，对比不同检 查方式对残存病灶、阳性淋巴结的诊断价 值，比较精确放疗前后SUVmax及ADC值变 化情况，并以疗效等级暴露分组，对比不 同疗效等级下残存病灶患者SUVmax及ADC 值的差异，以明确口咽癌患者术后精确放 疗应用MRI和18FDG PET-CT检查的临床价 值。结果 ①18FDG PET-CT诊断残存病灶 的准确率为94.33%、特异度为94.87%、灵 敏度为92.85%、阳性预测值为86.67%、阴 性预测值为97.36%、kappa值为0.857；诊 断阳性淋巴结的准确率为95.26%、特异度 为95.58%、灵敏度为92.30%、阳性预测值 为80.00%、阴性预测值为98.56%。Kappa 值为0.828，均高于MRI；②术后残存病灶 及术后原发病灶经精确放疗后可见SUVmax 显著下降，但放疗1个月与放疗3个月时其 SUVmax对比差异无统计学意义(P﹥0.05)； 结论 18FDG PET-CT用于口咽癌患者术后 精确放疗中或具更好的应用价值，值得临 床推介。

Objective To analyze the clinical value of magnetic resonance imaging (MRI) and 18 fluorodeoxyglucose positron emission computed tomography (18FDG PET-CT) in precise radiotherapy of patients with oropharyngeal cancer after operation. Methods The MRI and 18FDG PET-CT data of 49 patients with oropharyngeal cancer who underwent precise radiotherapy in the hospital from August 2014 to July 2017 were analyzed retrospectively. The value of different examination methods in the diagnosis of residual lesions and positive lymph nodes was compared. The SUVmax and ADC values were compared before and after precise radiotherapy, and between patients with residual lesions and different therapeutic effects to clarify the clinical value of MRI and 18FDG PET-CT in precise radiotherapy ofpatients with oropharyngeal cancer after operation. Results ①The accuracy rate, specificity, sensitivity, positive predictive value and negative predictive value of 18FDG PET-CT in the diagnosis of residual lesions were 94.33%, 94.87%, 92.85%, 86.67% and 97.36%, respectively, and the Kappa value was 0.857. The accuracy rate, specificity, sensitivity, positive predictive value and negative predictive value in the diagnosis of positive lymph nodes were 95.26%,95.58%,92.30%, 80.00%, and98.56%, respectively, and the Kappa value was 0.828. All of them were higher than those of MRI. ②After precise radiotherapy of residual lesions and positive lymph nodes, the SUVmax decreased significantly, with statistically significant difference between groups (P<0.05), but there was no significant difference in SUVmax after 1 month and 3 months of radiotherapy (P>0.05). Conclusion 18FDG PET-CT can be used in precise radiotherapy of patients with oropharyngeal cancer after operation.