Difference in radiotherapy dose caused by different ways of adding bolus
10.3760/cma.j.issn.1004-4221.2016.04.018
- VernacularTitle:组织补偿膜添加方式引起的放疗剂量差异研究
- Author:
Zuohuai HU
;
Jiandong FU
;
Fang CHEN
;
Daquan ZHANG
;
Maohong LIANG
;
Shu YAN
;
Dong LI
;
Jianwen WANG
;
Yuju BAI
- Publication Type:Journal Article
- Keywords:
Breast neoplasms/radiotherapy;
Beast wall/radiotherapy;
Dosimetry
- From:
Chinese Journal of Radiation Oncology
2016;25(4):388-390
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the difference in radiotherapy dose caused by different ways of adding bolus.Methods A total of 20 patients who needed to receive postmastectomy chest wall irradiation from October to December on 2014 were selected.Each patient underwent two CT scans;CT-1 was to perform CT scan directly without bolus, and CT-2 was to perform CT scan after adding bolus to the body surface.An equivalent bolus was added for CT-1 in the radiotherapy planning system, and Plan-1, which met the clinical requirements, was performed.Then Plan-1 was put on CT-2 through image fusion and plan verification to develop Plan-2, which was to develop plans with equivalent boluses at other times and perform radiotherapy with a bolus added to the surface of the body.At last, CT-2 was used to perform radiotherapy Plan-3, which met the clinical requirements.The paired t-test was used for comparison of clinical data between any two plans with SPSS 19.0.Results The V20 of the whole lung, V20 of the diseased lung, V30 of the heart, and Dmax of the healthy breast showed no significant differences across the three plans (P=0.074-0.871).The V50 , V55 , conformity index, and homogeneity index of the planning target showed significant differences across the three plans, and the total number of monitor units showed a significant difference between Plan-1 and Plan-2(P=0.002-0.049).The dose distribution in the target volume and the number of monitor units in each radiation field also showed significant differences.Conclusions When the equivalent bolus is added to the body surface before CT scan, such a plan can accurately reflect the dose distribution of the planning target and the dose to organs at risk.
