Enhancing Delivery Efficiency on the Elekta Unity MR-Linac: A Dosimetric Study on Planning Parameters
Abstract
Purpose
One major bottleneck in MRI-guided online adaptive radiotherapy is the prolonged treatment process, particularly extended delivery times, partly due to the relatively low dose rate and high prescription doses. Efficient radiation delivery is essential for maintaining patient comfort and improving clinical throughput. This study investigates optimal planning and optimization parameter strategies to enhance delivery efficiency while maintaining high dosimetric quality.
Methods
Ten prostate and ten liver patients were included, and for each patient three plans were generated: (1) a clinical plan, (2)Refa: a segment-limited plan with the maximum number of segments constrained to 0.05). All adaptive plans were generated within 5–13 min, consistent with clinical online optimization timelines, and all plans met dosimetric goals, with estimated delivery times showing consistent time-saving trends.
Conclusion
Systematic adjustment of Unity IMRT planning parameters can markedly improve delivery efficiency while maintaining dosimetric quality. These findings provide practical, evidence-based guidelines for parameter selection in Unity planning, supporting reduced treatment times, improved patient throughput, and broader clinical feasibility of MR-guided online adaptive radiotherapy.