摘要
目的探索放疗计划设计时,当食管癌定位中心与靶区中心位置偏差在X(左右方向)、Y(头脚方向)、Z(上下方向)三维方向小于±15 mm时,计划中心的改变情况对放疗计划质量的影响。方法选取在商洛市中心医院接受食管癌放射治疗的40例患者为研究对象。首先以计划靶区(Planning Target Volume,PTV)中心为计划中心设计放疗计划,待计划优化完成后,将靶区中心沿X、Y、Z三个方向分别平移±5、±10、±15 mm,并以此点为计划中心,重新设计放疗计划,统计剂量学参数,评价计划的可行性。结果靶区、危及器官、计划执行效率指标差异均无统计学意义(P>0.05)。与计划中心在PTV中心组相比,其他组PTV最大剂量(D_(max))、最小剂量、平均剂量(D_(mean))、均匀性指数、适形度指数的变化范围(百分比)为:-0.15%~0.12%、-0.05%~0.05%、-0.07%~0.09%、-0.09%~0.28%、-0.36%~0.48%;肺V5(器官受到500 cGy剂量的体积百分比,其他以此类推)、V_(10)、V_(20)、V_(30)、D_(mean)最大偏差分别为0.68%、0.29%、0.40%、-0.14%、7.75 cGy;心脏V_(10)、V_(20)、V_(30)、V_(40)、D_(mean)最大偏差分别为0.66%、-0.30%、-0.47%、0.54%、-14.08 cGy;脊髓D_(max)最大偏差为28.98 cGy;机器跳数、计划执行时间、计划优化时间最大偏差分别为-34.01 MU、5.33 s、-6.09 s。结论当定位中心和靶区中心在X、Y、Z三个方向的位移小于±15 mm时,可以直接将定位中心作为计划中心进行放疗计划的设计,以便减少患者的复位时间和复位时的二次摆位误差。
Objective To explore the change of planning center and its effect on the quality of radiotherapy plan when the deviation between the esophageal cancer positioning center and the target area center in the X(left-right),Y(head-foot),Z(up-down)three-dimensional direction is less than±15 mm in the planning stage.Methods A total of 40 patients receiving dynamic intensity modulated radiotherapy in Shangluo Central Hospital were selected as the study objects.Firstly,The planning target volume(PTV)center was used to design the radiotherapy plan.After the plan optimization was completed,the new radiotherapy plan was designed by shifting the planning center±5,±10 and±15 mm in three directions towards X,Y,Z,and this point was used as the planning center.The feasibility of the plan was assessed using statistical dosimetric parameters.Results There was no statistical significance in target area,organ at risk and plan execution efficiency(P>0.05).Compared with PTV center plan,the variations in maximum dose(D_(max)),minimum dose,average dose(D_(mean)),homogeneity index and conformity index in other groups ranged from-0.15%~0.12%,-0.05%~0.05%,-0.07%~0.09%,-0.09%~0.28%,and-0.36%~0.48%.The maximum deviation of lung doses at V5(percentage of the volume of the organ receiving 500 cGy dose,and so on),V_(10),V_(20),V_(30) and D_(mean) were 0.68%,0.29%,0.40%,-0.14%and 7.75 cGy.The maximum deviation of heart doses at V_(10),V_(20),V_(30),V_(40) and D_(mean) were 0.66%,-0.30%,-0.47%,0.54%and-14.08 cGy.Maximum deviation of spinal-cord D_(max) was 28.98 cGy.The maximum deviations of monitor unit,delivery time and planned optimization time were-34.01 MU,5.33 s and-6.09 s.Conclusion When the positioning center and the PTV center in the X,Y,Z,direction is less than±15 mm,the positioning center can be directly used as the planning center to design the radiotherapy plan,so as to reduce the patient’s reset time and the positioning error.
作者
王浩
郭峰
车亚
任英红
丁绮
杨蕴一
李毅
WANG Hao;GUO Feng;CHE Ya;REN Yinghong;DING Qi;YANG Yunyi;LI Yi(Department of OncologyⅢ,Shangluo Central Hospital,Shangluo Shaanxi 726000,China;Department of Pharmacy,Shangluo Central Hospital,Shangluo Shaanxi 726000,China;Department of Radiation Oncology,The First Affiliated Hospital of Xi’an Jiaotong University,Xi’an Shaanxi 710061,China)
出处
《中国医疗设备》
2024年第11期44-50,共7页
China Medical Devices
基金
陕西省自然科学基础研究计划面上项目(2020JM-396)
商洛市科学技术局项目(2022-Y-0044)。
关键词
食管癌
动态调强放疗
定位中心
计划质量
剂量学
位置偏差
靶区中心
esophageal cancer
dynamic intensity modulated radiotherapy
positioning center
quality of plans
dosimetry
deviation of position
target area center