The calibration of CT modeling for proton therapy treatment planning system
10.3760/cma.j.cn113030-20231228-00214
- VernacularTitle:质子治疗计划系统CT建模的校准
- Author:
Renchao ZHENG
1
;
Xiaoguang LU
;
Weiqing WU
;
Zu'an ZHENG
;
Zhiping XIAO
;
Junchao LI
;
Xianglin YUAN
Author Information
1. 华中科技大学同济医学院附属同济医院肿瘤科，武汉 430030
- Keywords:
Proton therapy;
Treatment planning system;
CT modeling;
Stoichiometric calibration
- From:
Chinese Journal of Radiation Oncology
2024;33(10):935-941
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To verify and calibrate the CT modeling curves of three CT devices in RayStation proton treatment planning system (TPS).Methods:CT-mass density (CT-MD) curves were established by CT Hounsfield units of different tissue substitute materials obtained by scanning the model with CT equipment. CT-stopping power (CT-SP) curves were established by calculation based on the chemical composition of various human tissues. The equivalent water thickness of tissue substitute modules was calculated with different CT modeling curves in TPS. The actual equivalent water thickness of various modules was measured by a Bragg peak detector, and compared with the calculated values of TPS to verify the accuracy of different CT models.Results:The differences of CT modeling curves were significantly different under different tube voltage scanning protocols. Compared with CT-MD curves, CT-SP curves based on the stoichiometric calibration were more suitable for proton dose calculation. However, the values of stopping power corresponding to high CT values still needed to be optimized, and the calculation error after calibration was less than 3%.Conclusion:The method of verifying and calibrating CT unit curves of proton TPS is described, proving that the CT-SP curves after stoichiometric calculation are more suitable for proton dose calculation.
