质子闪光放射治疗中子剂量分析

摘要/Abstract

摘要： 利用蒙特卡罗程序计算了超高剂量率质子FLASH束流条件下,降能器在治疗室内和室外两种布置方案下束流产生的次级中子在水模型中的分布。计算结果显示,质子能量为70~116 MeV的放疗条件下,室内降能器产生的中子在水模型内的剂量率和累积剂量可以达到无降能器时的十几倍。对于有室内降能器情形,在质子能量较低的情况下,靶区质子剂量为60 Gy时周边区域的累积中子剂量可以达到200 mGy以上。

关键词: 质子治疗, 中子剂量, 蒙特卡罗, 次级辐射, 闪光放射治疗

Abstract: The distribution of secondary neutrons in the water model under the condition of ultra-high dose rate proton beam (FLASH ) is calculated by Monte Carlo method. The calculation results show that the distribution of neutrons produced by the indoor energy degrader in the water phantom can reach ten times of that without the degrader when the proton energy is from 70 to 116 MeV. In the case of low proton energy, the cumulative neutron dose of one treatment can reach more than 200 mGy.

Key words: proton therapy, neutrons dose, Monte Carlo, energy reducer, FLASH

中图分类号:

TL72

李坤东, 张海旸, 贾昧超, 肖杰. 质子闪光放射治疗中子剂量分析[J]. 辐射防护, 2025, 45(3): 285-291.

LI Kundong, ZHANG Haiyang, JIA Meichao, XIAO Jie. Analysis on neutron dose at proton FLASH therapy room[J]. RADIATION PROTECTION, 2025, 45(3): 285-291.

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