• 대한방사선기술학회지:방사선기술과학
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• 제47권4호
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• pp.271-278
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• 2024

This study aimed to evaluate the impact of changes in beam arrangement and arc counts on dosimetric factors in volumetric modulated arc therapy (VMAT) inverse radiation therapy planning for hippocampal-avoidance whole brain radiation therapy (HA-WBRT) by using the Elekta Monaco radiation therapy planning system (RTPs). For coplanar VMAT, both the arc per beam (APB) method and the beam determined arc(BDA) method, which is determined by the number of beams, were applied. For non-coplanar VMAT, the BDA method was utilized, and a total of 9 treatment plans were established by varying the arc counts. All radiation therapy plans met the radiation oncology group (RTOG) 0933 protocol standards, and 14 dosimetric factors were compared and analyzed. The results showed that the BDA-NC VMAT method demonstrated superior performance in terms of planning target volume (PTV) coverage and protection of normal organs, while APB-VMAT was advantageous in terms of hippocampal protection, monitor unit and delivery time. This study is expected to contribute to the efficient establishment of HA-WBRT plans considering the changes in beam arrangement and rotation arc numbers in Monaco RTPs.