Quantitative analysis of motion of cardiac substructures in deep inspiratory breath holding radiotherapy for left breast cancer
10.19745/j.1003-8868.2025048
- VernacularTitle:左侧乳腺癌深吸气屏气放疗中心脏亚结构运动的量化分析
- Author:
Zhao-hui TANG
1
;
Zhe ZHANG
;
Wei-bin MAO
;
Bo HUANG
;
Jun-feng AI
;
Chao-fan ZHU
;
Zhi-chao XIE
;
Ya-jie LIU
Author Information
1. 北京大学深圳医院放射治疗科,广东 深圳 518000
- Publication Type:Journal Article
- Keywords:
breast cancer;
deep inspiration breath holding;
radiotherapy;
cardiac substructure;
coronary computed tomogra-phy angiography
- From:
Chinese Medical Equipment Journal
2025;46(3):54-58
- CountryChina
- Language:Chinese
-
Abstract:
Objective To quantify the volume and movement of cardiac substructures by using coronary computed tomography angiography(CCTA)to provide guidance for the design of deep inspiratory breath-holding radiation therapy for left breast cancer and the protection of organs at risk.Methods Totally 18 female patients who received conventional chest plain scan and CCTA were selected to simulate the design process of radiotherapy plan for left breast cancer patients with internal mammary lymph nodes.Retrospective reconstruction of CCTA data was performed for each patient,with 10 phase images(with an interval of 10%)within a R-R cardiac cycle(10%-100%)to simulate the true range of motion of the heart.The heart,left atrium(LA),left ventricle(LV),right atrium(RA),right ventricle(RV),left anterior descending artery(LAD),left circumflex coronary artery(LCX)and right coronary artery(RCA)were contoured at each phase.The distances from the centroid position to the average position of LAD,LCX and RCA were measured at each phase in the superior-inferior(SI),anterior-posterior(AP)and left-right(LR).The average volume and range of volume changes of LA,LV,RA,RV and heart were analyzed within a cardiac cycle.The expansion margins of planning organs at risk volume(PRV)were calculated.SPSS 19.0 software was used for statistical analysis.Results The following average absolute displacements were found in SI,AP and LR coordinates:(1.8±0.7)mm,(1.2±0.5)mm and(1.5±0.5)mm for LAD,respectively;(2.1±0.7)mm,(1.5±0.6)mm and(1.9±0.7)mm for LCX,respectively;(1.6±0.5)mm,(2.2±0.9)mm and(2.2±0.8)mm for RCA,respectively.The volume changes of LA,LV,RA,RV and heart within a cardiac cycle ranged from 34.3 to 63.9 cm3,122.1 to 154.3 cm3,29.3 to 53.6 cm3,57.2 to 94.3 cm3 and 480.1 to 515.4 cm3,respectively.The theoretical expansion margins of LAD,LCX and RCA in all the three directions were within 2 mm.Conclusion The ranges of movement and volume changes of cardiac substructure are quantitati-vely displayed,and references are provided for the planning of deep inspiratory breath-holding radiation therapy for left breast cancer and the protection of organs at risk.[Chinese Medical Equipment Journal,2025,46(3):54-58]