不同金属材质假牙对舌癌放疗患者肿瘤靶区的剂量学参数影响  

Dosimetry Effect of Different Metal Dentures on Gross Tumor Volume of Patients with Tongue Cancer

作　　者：卢琳[1,2,3] 郭翌 曾疆 李发挥 郭飞宝 LU Lin;GUO Yi;ZENG Jiang;LI Fahui;GUO Feibao(Department of Radiotherapy,Cancer Center,The First Affiliated Hospital of Fujian Medical University,Fuzhou 350005,China;Department of Radiotherapy,National Regional Medical Center,Binhai Campus of the First Affiliated Hospital,Fujian Medical University,Fuzhou 350212,China;Key Laboratory of Radiation Biology of Fujian Higher Education Institutions,Fuzhou 350005,China)

机构地区：[1]福建医科大学附属第一医院肿瘤中心放疗科,福州350005 [2]福建医科大学附属第一医院滨海院区国家区域医疗中心放疗科,福州350212 [3]放射生物福建省高等学校重点实验室,福州350005

出　　处：《福建医科大学学报》2024年第3期200-205,共6页Journal of Fujian Medical University

基　　金：福建省自然科学基金青创项目(2021J05146);福建省卫生健康科技计划项目(2022GGA025)。

摘　　要：目的探讨舌癌放疗患者植入的不同金属材质假牙对肿瘤靶区(GTV)的剂量学影响。方法建立由组织补偿膜、牙齿和标准固体水组成的模体,获取镍铬合金、二氧化锆和钴铬合金3种金属假牙组成的模体CT图像。在假牙后方设置不同深度、半径为1.9 cm的GTV,并设计单射束开野照射计划和容积旋转调强放疗(VMAT)计划。计算CT下不同假牙的靶区剂量分布,分析不同假牙对靶区剂量学参数的影响。结果与正常牙齿比较,镍铬合金、二氧化锆和钴铬合金3种金属假牙引起的最大剂量(D_(max))和平均剂量(D_(mean))计算偏差均<3%,其中二氧化锆假牙对靶区剂量影响最大。当GTV深度为5.9 cm时,金属假牙导致的靶区剂量偏差最大。结论金属假牙产生的CT伪影可影响舌癌放疗的靶区剂量。当GTV离金属假牙较近时,需要考虑拔除假牙或使用伪影修正算法对定位CT图像进行伪影修正。Objective To investigate the dosimetry impact of different metal dentures on gross tumor volume(GTV)in patients with tongue cancer undergoing radiotherapy.Methods A phantom composed of bolus,teeth,and standard solid water was established.CT images of the phantom with three types of metallic dental prostheses,nickel-chromium alloy,zirconium dioxide,and cobalt-chromium alloy,were obtained.GTVs of different depths with a radius of 1.9 cm were set behind the dentures.An single beam open\|field plan and volumetric modulated arc therapy(VMAT)plan were designed.The dose distribution to the target area with different metal dentures was calculated and analyzed to determine the impact of each prosthesis on dosimetric parameters.Results Compared with normal teeth,the calculation deviation of maximum dose(D max)and average dose(D mean)caused by different metal dentures were less than 3%,and zirconia dentures had the greatest effect on target dose.The maximum dose deviation caused by metallic prostheses occurred at a GTV depth of 5.9 cm.Conclusions CT artifacts generated by metal dentures can affect the target dose of radiotherapy for tongue cancer.It is necessary to consider removing the patient s dentures or using the artifact correction algorithm to adjust the localization CT images when the GTV is close to the metal dentures.

关 键 词：金属假牙 放射治疗 剂量学 

分 类 号：R739.86[医药卫生—肿瘤] R730.55[医药卫生—临床医学]