个体化口腔支架在鼻咽癌患者调强放疗中应用的剂量分析

Dosimetric Analysis of Individual Dental Stent in Intensity Modulated Radiation Therapy for Nasopharyngeal Carcinoma Patients

【目的】在调强放疗(IMRT)中运用个体化口腔支架并通过剂量学分析,探索个体化口腔支架是否能有效减少鼻咽癌患者舌及口腔黏膜的照射体积及剂量,从而起到保护作用。【方法】将按入组条件收治的鼻咽癌患者随机分为试验组和对照组。临床上共收治初治鼻咽癌患者40例,其中试验组22例,对照组18例。两组患者均采用IMRT技术,试验组佩戴口腔支架,对照组不佩戴。两组患者均根据病情需要采用诱导、同期或辅助化疗,并酌情使用放射增敏剂。在保证处方剂量和优化目标一致的前提下进行剂量学分析,比较两组舌和口腔黏膜等所受的照射剂量和体积。【结果】调强剂量学分析表明两组患者靶区剂量适形度和均匀度无明显差异,而试验组舌、口腔黏膜及腮腺、脊髓等其他正常组织的受照剂量较对照组明显下降。【结论】鼻咽癌患者调强放疗中佩戴个体化口腔支架在不影响靶区剂量的前提下可减少口腔黏膜和舌的受照剂量和受照体积,及保护腮腺、下颌骨、中耳、脊髓等正常组织。

[Objective] To explore the role of individual dental stent in sparing normal tissues for primary nasopharyngeal carcinoma （NPC） patients in IMRT. [ Methods ] In this dosimetric analysis, a total of 40 patients were randomized into two groups： 22 in trial group, 18 in control group. The trial group wore individual dental stent during IMRT radiotherapy, while did not in the control group. [ Results ] In the dosimetric analysis, the conformal index （CI） and uniformity index （UI） of the two groups were similar. The dosimetric analysis also proved that the irradiation dose and volume of the tongue and oral mucosa decreased obviously when wearing the individual dental stent. And the normal tissues, such as patotid, mandibular, spinal cord et al, had lower doses in the trial group. [ Conclusions ] Individual dental stent can be used in IMRT for nasopharyngeal carcinoma, not only to reduce the irradiation dose and volume of tongue and oral mucosa, but also protect more normal tissues.