ORIGINAL RESEARCH article
Front. Oncol.
Sec. Radiation Oncology
Volume 15 - 2025 | doi: 10.3389/fonc.2025.1612643
This article is part of the Research TopicInnovative Approaches in Precision Radiation OncologyView all 13 articles
Dosimetric analysis of Orthogonal Collimator Configuration in Volumetric Modulated Arc Therapy Planning: A Comparative Study
Provisionally accepted
- 1Tianjin Union Medical Centre, Nankai University, Tianjin, China
- 2National Cancer Center, Chinese Academy of Medical Sciences, Beijing, China
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
AbstractBackground: In volumetric modulated arc therapy (VMAT), collimator angle selection impacts dose distribution and plan quality. Conventional VMAT plans use dual arcs with collimators set at 0o. This study explores the dosimetric effects of using orthogonal collimator angles (0o and 90o) in dual-arc VMAT.Methods: Thirty patients with head and neck, thoracic, and abdominal tumors were analyzed. Two VMAT plans were generated: Plan A (0o collimator angle) and Plan B (0o and 90o collimator angles). Dosimetric endpoints included conformity index (CI), gradient measure (GM), homogeneity index (HI), dose to organs at risk (OARs), mean dose to normal tissues (Dmean, NT), monitor units (MU), and gamma pass rate (GPR).Results: Plan B improved dosimetric outcomes over Plan A. HI decreased by 0.03 in the rectum, 0.01 in the breast, and 0.01 in the larynx. GM decreased by 0.15 cm in the rectum, 0.05 cm in the breast, and 0.01 cm in the larynx. OAR doses were reduced across sites, with notable decreases in the bladder (−4.62 Gy), left anterior descending artery (−3.99 Gy), and spinal cord (−1.79 Gy). Dmean,NT was slightly reduced in the rectum, breast and larynx. MU increased in rectum plans (+41 MU) , but decreased in the breast and laryngeal plans by 38 MU and approximately 73 MU, respectively. All plans achieved GPR > 95%.Conclusion: Incorporating orthogonal collimator angles (0o and 90o) in dual-arc VMAT enhances dose conformity and spares OARs without compromising target coverage or delivery accuracy. This approach is clinically applicable with minimal workflow changes.
Keywords: Radiotherapy, Radiotherapy treatment planning, volumetric modulated arc therapy, orthogonal collimator angles, dose conformity and homogeneity
Received: 16 Apr 2025; Accepted: 30 Jun 2025.
Copyright: © 2025 Huang, guo, liu, Men and wang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Xin Huang, Tianjin Union Medical Centre, Nankai University, Tianjin, 300071, China
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.