An Evaluation of the Feasibility and Utility of Automated HyperArc Planning for Multiple Brain Metastases: A Comparative Dosimetric Analysiss

Öznur Şenkesen; Emine Burçin İspir; Zeynep Özen; Ufuk Abacioğlu

doi:10.31067/acusaglik.1687276

An Evaluation of the Feasibility and Utility of Automated HyperArc Planning for Multiple Brain Metastases: A Comparative Dosimetric Analysiss

Abstract

Purpose: This study compared automated HyperArc (HA) planning with manually designed VMAT plans for treating patients with multiple brain metastases. Materials and Methods: Ten patients with an average of 15 metastases (range: 10–23) were retrospectively analyzed. All underwent high-resolution CT imaging (1 mm slice thickness) registered to contrast-enhanced MRI. Targets were delineated by a radiation oncologist. For lesions ≥10 mm, the gross tumor volume (GTV) equaled the planning target volume (PTV); for smaller lesions, a 1 mm margin was added. VMAT plans used a single isocenter and non-coplanar arcs, while HA plans were generated with automated optimization. Prescribed doses ranged from 20 to 30 Gy, delivered over 3–5 fractions. Dosimetric parameters compared included conformity index (CI), gradient index (GI), homogeneity index (HI), healthy brain V10Gy and V12Gy, maximum and mean brainstem doses, and maximum doses to optic structures and lenses. Total monitor units (MU) were also assessed. Results: Target coverage was similar between VMAT and HA, with no significant differences in CI (p = 0.721) or GI (p = 0.241). HA showed improved homogeneity and significantly reduced doses to healthy brain (lower V10Gy) and critical structures including brainstem (p = 0.009) and optic chiasm (p = 0.013). HA also required about 65% fewer MUs than VMAT (p = 0.007), indicating shorter treatment times. Conclusion: HA planning provided superior sparing of healthy brain tissue and critical structures and improved treatment efficiency compared to VMAT. HA represents a promising automated approach for stereotactic radiosurgery in complex multi-target cases

Keywords

Supporting Institution

This study was prepared without any external source of funding

Ethical Statement

This study was approved by internal ethics review board

References

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Details

Primary Language

English

Subjects

Clinical Sciences (Other)

Journal Section

Research Article

Authors

Öznur Şenkesen ^*
0000-0002-6004-086X
Türkiye

Emine Burçin İspir
0000-0003-4946-5135
Türkiye

Zeynep Özen
0009-0002-8179-6612
Türkiye

Ufuk Abacioğlu
0000-0002-3950-8616
Türkiye

Early Pub Date

September 23, 2025

Publication Date

October 1, 2025

Submission Date

May 1, 2025

Acceptance Date

June 16, 2025

Published in Issue

Year 2025 Volume: 16 Number: 4

DOI

https://doi.org/10.31067/acusaglik.1687276

IZ

https://izlik.org/JA22UL46FM

Cite

RIS / Bibtex

EndNote

Şenkesen Ö, İspir EB, Özen Z, Abacioğlu U (October 1, 2025) An Evaluation of the Feasibility and Utility of Automated HyperArc Planning for Multiple Brain Metastases: A Comparative Dosimetric Analysiss. Acıbadem Üniversitesi Sağlık Bilimleri Dergisi 16 4 560–566.