Shortening the delivery time of proton therapy by real-time compensation method with raster scanning  

作　　者：Xiang-Shang Sun Yong-Jiang Li Jun-Ya Liu Wen-Tao Liao Chao Wu Yue-Hu Pu 

机构地区：[1]Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]Shanghai APACTRON Particle Equipment Co.,Ltd,Shanghai 201800,China [4]Shanghai Advanced Research Institute,Chinese Academy of Sciences,Shanghai 201210,China [5]Medical Equipment Innovation Research Center,West China Hospital,Sichuan University,Chengdu 610041,China

出　　处：《Nuclear Science and Techniques》2022年第6期62-74,共13页核技术（英文）

基　　金：supported by the National Key Research and Development Program of China(No.2016YFC0105408)。

摘　　要：Among the various scanning techniques, spot and raster scanning are the most frequently adopted. Raster scanning turns off the beam only when each isoenergy slice irradiation is completed. This feature intrinsically solves the leakage dose and frequent beam-switching problems encountered during spot scanning. However, to shorten the delivery time of raster scanning, a sophisticated dose control strategy is required to guarantee dose distribution.In this study, a real-time compensation method with raster scanning for synchrotron systems was designed. It is characterized by a small spot-spacing planning strategy and real-time subtraction of the transient number of particles delivered between two planning-spot positions from the planned number of particles of the subsequent raster point.The efficacy of the compensation method was demonstrated by performing accurate raster scanning simulations with an in-house simulation code and accurate final dose evaluations with a commercial treatment planning system.Given the similar dose evaluation criteria under a practical high scanning speed, compared with the spot scanning method, the total delivery time of the compensated raster scanning method was significantly shortened by 53.3% in the case of irradiating a cubical target and by 28.8% in a pelvic case. Therefore, it can be concluded that real-time compensated raster scanning with a fast scanning configuration can significantly shorten the delivery time compared to that of spot scanning. It is important to reduce the pressure on patients caused by prolonged immobilization and to improve patient throughput capacity at particle therapy centers.

关 键 词：Proton therapy Raster scanning Delivery time Scanning simulation 

分 类 号：R730.55[医药卫生—肿瘤]