准直器角度与肝癌体部立体定向放射治疗计划剂量学相关性研究

肝癌电子杂志 ›› 2025, Vol. 12 ›› Issue (4): 37-42.

准直器角度与肝癌体部立体定向放射治疗计划剂量学相关性研究

戴宛庭, 董宇, 王秋实, 范鹏飞, 李宇恒, 吴登斌^*

鞍钢集团总医院肿瘤医院放射治疗中心,辽宁鞍山 114000

收稿日期:2025-03-21 出版日期:2025-12-30 发布日期:2026-01-16
通讯作者: ^* 吴登斌,E-mail：dwtaaiinng@163.com
基金资助:
辽宁省科技厅揭榜挂帅科技攻关项目（2021JH1/10400051）

Study on the correlation between collimator angles and dosimetry in stereotactic radiotherapy planning for liver cancer

Dai Wanting, Dong Yu, Wang Qiushi, Fan Pengfei, Li Yuheng, Wu Dengbin^*

Radiation Therapy Center, Ansteel Group General Hospital, Anshan 114000, Liaoning, China

Received:2025-03-21 Online:2025-12-30 Published:2026-01-16
Contact: * Wu Dengbin, E-mail: dwtaaiinng@163.com

摘要/Abstract

摘要： 目的：研究不同准直器角度与肝癌体部立体定向放射治疗（stereotactic radiotherapy, SRT）计划剂量的相关性,为临床肝癌SRT计划设计提供准直器角度选择依据。
方法：回顾分析2018—2024年20例肝癌SRT治疗计划,在保持其他参数一致条件下,分别创建准直器角度为0°/0°~80°/280°的9组计划。采用弗里德曼检验比较靶区适形性指数（conformity index,CI）、梯度指数（gradient index, GI）,正常肝脏V₁₀、V₂₀、V₃₀、平均剂量,脊髓0.03 cm³剂量（D_{0.03 cm3}）,机器跳数及3%/2mm标准下的γ通过率差异。
结果：随着准直器角度的改变,靶区CI、GI,正常肝脏V₁₀、V₃,脊髓D_{0.03 cm3},以及机器跳数均产生了较大的差异性（均P<0.05）;而正常肝脏V₂₀、平均剂量和γ通过率产生的差异无统计学意义（均P>0.05）。
结论：准直器角度选择可优化靶区剂量分布并减少正常组织受量,对肝癌SRT计划设计具有临床指导价值。

关键词: 肝癌, 体部立体定向放射治疗, 准直器角度, 剂量学, γ通过率;

Abstract: Objective: To study the dosimetric effect of different collimator angle on stereotactic radiotherapy (SRT) for liver cancer, providing a reference for collimator angle selection in clinical SRT plan design for liver cancer.
Methods: A retrospective analysis was conducted on 20 liver cancer patients treated with SRT from 2018 to 2024. Nine plans were generated with collimator angles ranging from 0°/0° to 80°/280° at 10° intervals, under identical planning parameters. The Friedman test was used to compare differences in conformity index (CI), gradient index (GI), normal liver V₁₀/V₂₀/V₃₀, mean liver dose, 0.03 cm³ spinal cord dose (D_{0.03 cm3} ), monitor units, and γ pass rate (3%/2mm standard).
Results: The results showed that changes in collimator angle significantly affected CI, GI, normal liver V₁₀ and V₃₀, spinal cord D_{0.03 cm3}, and monitor units, with statistically significant differences (all P< 0.05). However, no significant differences were observed in normal liver V20, mean liver dose, or γ pass rate (all P> 0.05).
Conclusion: Collimator angle selection can optimize target dose distribution and reduce normal tissue irradiation, offering valuable clinical guidance for SRT plan design in liver cancer.

Key words: Liver cancer, Stereotactic radiotherapy, Collimator angle, Dosimetry, γpassing rate

戴宛庭, 董宇, 王秋实, 范鹏飞, 李宇恒, 吴登斌. 准直器角度与肝癌体部立体定向放射治疗计划剂量学相关性研究[J]. 肝癌电子杂志, 2025, 12(4): 37-42.

Dai Wanting, Dong Yu, Wang Qiushi, Fan Pengfei, Li Yuheng, Wu Dengbin. Study on the correlation between collimator angles and dosimetry in stereotactic radiotherapy planning for liver cancer[J]. Electronic Journal of Liver Tumor, 2025, 12(4): 37-42.

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