Dosimetric study of avoidance sectors technique of Eclipse radiotherapy planning system in design of VMAT plan for NSCLC
10.3969/j.issn.1672-8270.2025.11.006
- VernacularTitle:Eclipse放射治疗计划系统Avoidance Sectors技术在非小细胞肺癌VMAT计划设计中的剂量学研究
- Author:
Jingtao HE
1
;
Jinmeng PANG
;
Jun ZHU
;
Qianxi NI
Author Information
1. 湖南省肿瘤医院 中南大学湘雅医学院附属肿瘤医院放射物理技术部 长沙 410013
- Publication Type:Journal Article
- Keywords:
Volumetric intensity-modulated arc radiotherapy(VMAT);
Non-small cell lung cancer(NSCLC);
Avoidance sector;
Dosimetry
- From:
China Medical Equipment
2025;22(11):46-49
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To study the dosimetric characteristics of the Avoidance Sectors function in the Eclipse planning system in the design of volumetric intensity-modulated arc radiotherapy(VMAT)plan for non-small cell lung cancer(NSCLC).Methods:The case data of 20 NSCLC patients who admitted to Hunan Provincial Cancer Hospital in 2024 were retrospectively selected,both free avoidance sectors volumetric(FASV)modulated arc therapy and avoidance sectors volumetric(ASV)modulated arc therapy were formulated for all patients.The dose parameters and the total number of machine unit(MU)of accelerator of the target area and organs at risk between two kinds of plans were compared.The correlation between the ratio(VPTV/Vlung)of planning target volume(PTV)to whole lung volume and the exposure dosimetry index of whole lung were further analyzed.Results:Comparative result between FASV plan and ASV plan indicated that the conformity index(CI)of the FASV plan was(0.83±0.07),which was better than that of the ASV plan(0.78±0.06),and the difference was significant(t=2.086,P<0.05).The V5 value(48.35±7.28)%of the whole lung in the ASV plan was significantly lower than that(57.68±6.63)%in the FASV plan(t=3.670,P<0.05).There were not statistically significant differences in the V20,V30 and mean dose(Dmean)of the whole lung and heart between two kinds of plans(P>0.05).There were not statistically significant differences in the maximum doses of the spinal cord and esophagus between two kinds of plans(P>0.05).The total MU value(444.8±78.9)of the ASV plan was less than that(518.27±70.9)of the FASV plan(t=2.682,P<0.05).The results of Pearson correlation analysis indicated that the correlative values between VPTV/Vlung and V20,V30,and Dmean of whole lung were respectively r=0.756,0.697,and 0.732 in FASV plan(P<0.05).Conclusion:For NSCLC patients,the ASV plan can effectively reduce V5 value of lung tissue,and decrease the total MU value of accelerator's irradiation.The avoidance sectors function is worthy of recommendation.In FASV plan,the VPTV/Vlung value appeared a positive correlation with whole lung V20,V30,and Dmean.It is very necessary to adopt individual management strategies for respiratory motion in reducing the irradiation range of target area.
