| 杨璟喆,李君利,邱睿,衣宏昌,武祯.碳离子放射治疗微剂量测量研究[J].中华放射医学与防护杂志,2021,41(10):758-764 |
| 碳离子放射治疗微剂量测量研究 |
| Study on microdosimetry for carbon ion radiotherapy |
| 投稿时间：2021-01-21 |
| DOI：10.3760/cma.j.issn.0254-5098.2021.10.007 |
| 中文关键词: 碳离子束 微剂量谱 SOI硅微剂量计 相对生物学效应 |
| 英文关键词:Carbon ion beam Microdosimetric spectrum Silicon on insulator microdosimetry Relative biological effectiveness |
| 基金项目:国家自然科学基金（11875036） |
|
| 摘要点击次数: 2172 |
| 全文下载次数: 1016 |
| 中文摘要: |
| 目的 测量碳离子束的微剂量谱并计算其相对生物学效应（RBE）分布，为放射治疗微剂量研究提供参考。方法 使用绝缘体上硅（SOI）微剂量计对兰州重离子加速器国家实验室提供的260 MeV/u的12C离子束流进行微剂量谱测量，测量所得的脉冲幅度谱经转化得到剂量分布，通过摆放不同厚度聚甲基丙烯酸甲酯（PMMA）的组合，实现不同PMMA深度微剂量谱及RBE值的测量。结果 测量得到不同PMMA深度下260 MeV/u的12C离子束的微剂量谱，以及剂量线能yD与RBE随PMMA深度的变化关系。PMMA深度为116.5 mm处，RBE值达到2.6的峰值，并在布拉格峰位后迅速下降，但在拖尾处RBE值仍有1.3约为坪区入口处的2倍。结论 本文为碳离子束微剂量谱提供基础数据，12C离子束的RBE值随着PMMA深度增加逐渐上升并达到峰值，布拉格峰位后迅速下降但在拖尾处的生物效应不可忽略。同时体现了不同线能区间处的导致的剂量份额，为评估重离子治疗中继发癌症的风险提供参考。 |
| 英文摘要: |
| Objective To measure the microdosimetric spectrum of carbon ion beam and calculate the relative biological effect (RBE) distribution, so as to provide reference for radiotherapy microdosimetric research. Methods A silicon on insulator (SOI) microdosimeter was used to measure the microdosimetric spectrum of 12C ion beam, at 260 MeV/u, provided by Lanzhou Heavy Ion Accelerator National Laboratory. The measured pulse amplitude spectrum was converted to obtain the dose distribution. The microdosimetric spectra and RBE values at different polymethyl methacrylate depths were measured by the combination of different thickness PMMA. Results The microdosimetric spectra of 12C ion beam at 260 MeV/u were measured at different PMMA depths, and the relationship between dose line energy yD and RBE and different PMMA depths was also obtained. The measurement result showed that the RBE value reached a peak of 2.6 at the PMMA depth of 116.5 mm, and decreased rapidly after the Bragg peak. However, the RBE value was still 1.3 at the trailing point, which was about twice as much as the entrance of the flat zone. Conclusions This paper provides basic data for carbon ion beam microdosimetric spectroscopy through measurement. The RBE value of 12C ion beam gradually rises and reaches a peak with the increase of PMMA depth. After the Bragg peak position, it drops rapidly, but the biological effect at the tail cannot be ignored. At the same time, it reflects the dose fraction caused by different line energy intervals, and provides a reference for assessing the risk of heavy ion therapy for secondary cancer. |
| HTML 查看全文 查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|