鼻咽癌调强放疗中耳蜗受量评价

The evaluation of the cochlea in nasopharyngeal carcinoma treated with intensity- modulated radiation therapy

目的:回顾性分析鼻咽癌调强放疗对双侧耳蜗受量的影响。方法:选择已完成调强放射治疗的10例鼻咽癌患者,所有患者均有明确的病理诊断且均接受33次调强放疗。再由1名主治医师在原始的CT图像上勾画出双侧耳蜗,最后通过DVH图对双侧耳蜗受量进行分析,包括双侧耳蜗的最大剂量(Dmax)、最小剂量(Dmin)及平均剂量(Dmean)。结果:左侧耳蜗的最大剂量(Dmax)、最小剂量(Dmin)及平均剂量(Dmean)的均值分别为5203.8cGy、4054.5cGy、4579.5cGy;右侧耳蜗的最大剂量(Dmax)、最小剂量(Dmin)及平均剂量(Dmean)的均值分别为5647.3cGy、4573.5cGy、5076.7cGy。结论:在没有对耳蜗进行剂量限制并接受调强放疗的鼻咽癌患者,其耳蜗接受的照射剂量有超出推荐限制剂量(mean dose≤45Gy)的风险。

Retrospectively analyze the dose to the cochlea in patients with nasopharyngeal carcinoma （NPC）treated with intensity - modulated radiotherapy（IMRT）. Methods：Chose ten nasopharyngeal carcinoma pa-tients who have completed the intensity - modulated radiotherapy of 33 fractions. Then a attending physician contoured the cochlea in the original CT images. Finally,we analysed the dose volume histogram（DVH）of the left and right cochlea,including the maximum dose（Dmax ）,minimum dose（Dmin ）and the average dose（ Dmean ）. Results：The maximum dose of the left cochlea（Dmax ）,minimum dose（Dmin ）and the average dose（Dmean ）of mean were respec-tively 5203. 8cGy,4054. 5cGy,4579. 5cGy;and the right was 5647. 3cGy,4573. 5cGy,5076. 7cGy respectively. Con-clusion：There is a risk for nasopharyngeal carcinoma patients expose to the maximum dose to the cochlea exceeding the recommended restraints（mean dose ≤ 45Gy）when the cochlea was not outlined.