开发了光束角优化 (BAO) 算法来评估其临床可行性并研究不同 BAO 约束对乳腺癌治疗计划的影响。设计了一项由两部分组成的研究。第1部分，我们回顾性选择了20例保乳手术后接受放疗的患者。对于每位患者，使用 BAO 算法优化的波束角度以及与手动计划相同的优化约束来设计 BAO 计划。对 BAO 和手动计划之间的剂量测定指数进行了比较。第 2 部分纳入了 15 名左乳腺癌患者。对于每位患者，在 BAO 过程中建立三个不同的心脏约束（平均心脏剂量 < 5 Gy、3 Gy 或 1 Gy）以获得三个优化的射束组，分别标记为 BAO_H1、BAO_H3、BAO_H5。然后在相同的 IMRT 约束下使用这些射束组进行规划。对三组计划进行比较分析。对于第 1 部分，BAO 计划与手动计划在所有剂量学指标上均未观察到显着差异，但同侧肺 V5 除外，BAO 计划的表现略优于手动计划（35.5% ± 5.6% 与 36.9% ± 4.3%，p=0.034）。对于第 2 部分，更严格的 BAO 心脏约束导致更多垂直光束。然而，在相同IMRT约束下，BAO_H1、BAO_H3和BAO_H5之间的心脏剂量没有显着差异。同时，在 BAO 中，左肺剂量增加，而右乳房和肺剂量减少，心脏限制更严格。当 IMRT 约束下平均心脏剂量 < 5 Gy 时，右肺平均剂量从 BAO_H5 的 0.46 Gy 减少到 BAO_H1 的 0.33 Gy (p=0.027)。BAO 算法可以实现与手动计划相当的质量计划。 IMRT 约束主导最终计划剂量，而不同的 BAO 约束会改变结构之间的权衡，从而为规划设计提供额外的自由度。版权所有 © 2023 美国医学剂量师协会。由爱思唯尔公司出版。保留所有权利。

A beam angle optimization (BAO) algorithm was developed to evaluate its clinical feasibility and investigate the impact of varying BAO constraints on breast cancer treatment plans.A two-part study was designed. In part 1, we retrospectively selected 20 patients treated with radiotherapy after breast-conserving surgery. For each patient, BAO plans were designed using beam angles optimized by the BAO algorithm and the same optimization constraints as manual plans. Dosimetric indices were compared between BAO and manual plans. In part 2, fifteen patients with left breast cancer were included. For each patient, three distinct cardiac constraints (mean heart dose < 5 Gy, 3 Gy or 1 Gy) were established during the BAO process to obtain three optimized beam sets which were marked as BAO_H1, BAO_H3, BAO_H5, respectively. These sets of beams were then utilized under identical IMRT constraints for planning. Comparative analysis was conducted among the three groups of plans.For part 1, no significant differences were observed between BAO plans and manual plans in all dosimetric indices, except for ipsilateral lung V5, where BAO plans performed slightly better than manual plans (35.5% ± 5.6% vs 36.9% ± 4.3%, p = 0.034). For part 2, Stricter BAO heart constraints resulted in more perpendicular beams. However, there was no significant difference between BAO_H1, BAO_H3 and BAO_H5 with the same IMRT constraint in the heart dose. Meanwhile, the left lung dose was increased while the right breast and lung doses were decreased with stricter heart constraints in BAO. When mean heart dose < 5 Gy in IMRT constraint, the mean dose to the right lung was decreased from 0.46 Gy for BAO_H5 to 0.33 Gy for BAO_H1 (p = 0.027).The BAO algorithm can achieve quality plans comparable to manual plans. IMRT constraints dominate the final plan dose, while varying BAO constraints alter the trade-off among structures, providing an additional degree of freedom in planning design.Copyright © 2023 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.