广东医学2025，Vol.46Issue(6)：831-838,8.DOI:10.13820/j.cnki.gdyx.20250361
基于4D CT的外扩边界技术与呼吸门控治疗技术的剂量学差异比较
Dosimetric Comparison Between Margin Expansion Technique and Respiratory Gating Technique Based on 4D CT
摘要
Abstract
Objective To quantitatively evaluate the dosimetric differences and dose delivery accuracy between the margin expansion technique and the respiratory gating technique based on 4D CT,aiming to provide reference for clini-cal radiotherapy modality selection.Methods Treatment plans based on 4D CT were analyzed for 20 patients with lung cancer using both techniques.The evaluation included:(1)Measurement of static dose using a motion platform combined with SRS MapCHECK under static conditions;(2)Measurement of dynamic dose driven by patient-specific respiratory waveforms;(3)Gamma(γ)pass rate evaluation comparing both static and dynamic doses with planned doses;(4)Com-parison of planned dose parameters for target volumes and organs at risk(OARs),as well as treatment times.Results Using the 2％/1 mm γ evaluation criterion,the static γ pass rate for the margin expansion technique was(96.7±3.2)％,while the dynamic rate dropped to(59.9±14.4)％.In contrast,the respiratory gating technique achieved a static γ pass rate of(98.5±2.1)％and a dynamic rate of(90.5±7.3)％.The margin expansion technique exhibited a larger decline in dynamic γ pass rate[(37.9±15.7)％]compared to respiratory gating[(8.1±6.8)％].Dosimetric plan analysis showed that the margin expansion technique had a sharper dose falloff(R50％:3.88±0.28 vs.4.08±0.32),while the respiratory gating technique showed lower mean lung dose(Dmean:2.74±1.34 vs.3.30±1.72 Gy),lung V5(10.69±4.51 vs.12.43±5.29％),lung V20(2.84±1.77 vs.3.48±2.26％),and heart Dmean(2.35±1.64 vs.2.88±2.05 Gy).Conclusion Gamma analysis indicates that the respiratory gating technique provides higher dose delivery accuracy than the margin expansion technique.Additionally,it offers better protection for critical organs such as the lungs and heart.关键词
4D剂量/呼吸门控/立体定向放射治疗/γ分析/剂量评估Key words
4D dose/respiratory gating/stereotactic radiotherapy/gamma analysis/dose evaluation分类
医药卫生引用本文复制引用
陈郑超逸,叶惠玲,肖青,梁允信,张祥斌,钟仁明..基于4D CT的外扩边界技术与呼吸门控治疗技术的剂量学差异比较[J].广东医学,2025,46(6):831-838,8.基金项目
国家自然科学基金资助项目(12405390) （12405390）
四川省科技计划项目(2024YFFK0147) （2024YFFK0147）
