MRI精准模拟定位在局部晚期鼻咽癌调强放疗中的应用效果

目的:研究MRI精准模拟定位在局部晚期鼻咽癌调强放疗中的应用效果。方法:选取我院200例局部晚期鼻咽癌患者，采用随机数字表法分为对照组（n=100）和研究组（n=100），两组行调强放疗治疗，对照组只进行CT扫描，研究组经临床评估后行MRI及CT扫描，对比分析MRI精准模拟定位在局部晚期鼻咽癌调强放疗中的应用效果。结果:研究组放疗计划中平均靶区体积小于对照组（P<0.05）；研究组计划放疗靶区的CI、HI值低于对照组，更接近1（P<0.05）；研究组脑干、右侧视神经放疗计划中照射剂量低于对照组（P<0.05）；研究组1、3、5年生存率较对照组有升高趋势，1、3、5年野外复发率较对照组有下降趋势，但无统计学差异（P>0.05）。结论:MRI精准模拟定位在鼻咽癌放射治疗大体肿瘤靶区中可有效提高肿瘤靶区勾画的适形度及均匀性，减少不必要的照射体积，降低部分正常组织的照射剂量，可在一定程度上减少复发、提高患者生存率。

Application of precise simulated localization of MRI in intensity-modulated radiotherapy for locally advanced nasopharyngeal carcinoma

Objective:To study the effect of precise simulated localization of MRI in intensity-modulated radiotherapy (IMRT) for locally advanced nasopharyngeal carcinoma (NPC).Methods:200 patients with locally advanced nasopharyngeal carcinoma in our hospital were randomly divided into control group (n=100) and research group (n=100).The two groups were treated with intensity-modulated radiotherapy (IMRT).The control group only underwent CT scanning.The study group underwent MRI and CT scanning after clinical evaluation.The application effect of precise simulated localization of MRI in locally advanced nasopharyngeal carcinoma IMRT was compared and analyzed.Results:The average target volume of the study group was smaller than that of the control group (P<0.05).The CI and HI values of the study group were lower than those of the control group (P<0.05).The radiation dose of the brainstem and right optic nerve in the study group was lower than that of the control group (P<0.05).The survival rate of the study group was higher than that of the control group in 1，3 and 5 years，and the recurrence rate of the study group was lower than that of the control group in the field for 1，3 and 5 years，but there was no statistical difference (P>0.05).Conclusion:The precise localization of MRI in the gross tumor target of nasopharyngeal carcinoma radiotherapy can effectively improve the conformity and uniformity of the tumor target delineation，reduce the unnecessary volume of irradiation，and reduce the irradiation dose of some normal tissues，which can reduce the recurrence and improve the survival rate of patients to a certain extent.