@article{Ghulam Murtaza_Zaheer Abbas Gillani_Shahid Mehmood_Jalil Ur Rehman_Ehsan Ullah Khan_2021, title={Optimisation of user-selectable volumetric modulated arc therapy (VMAT) planning parameters: A study of VMAT arcs for prostate and head-and-neck cancers}, volume={71}, url={https://ojs.jpma.org.pk/index.php/public_html/article/view/532}, DOI={10.47391/JPMA.710}, abstractNote={<p><strong>Objective:</strong> To evaluate different VMAT planning techniques for a multi-leaf collimator (MLC)providing maximum aperture of 21 × 16 cm².</p> <p><strong>Methods: </strong>A VMAT planning study of nine prostate and nine head-and-neck cancer patients was carried out. The patients were previously treated with Intensity Modulated Radiotherapy (IMRT) technique during 2014-15, at radiation oncology SanBortolo Hospital, Vicenza, Italy. Three VMAT plans for each of prostate and head-and-neck cancer patient were optimized using Pinnacle treatment planning system for 6MV photon beam from ElektaSynergyS<sup>®</sup>Linac system. Single arc, dual arc and combined two independent-single-arcs were optimized for collimator angle 45°. VMAT treatment planning comparison was made among single-arc dual-arc and combined two independent-single-arcs. The student’s t-test (two-sided) with p ? 0.05 was applied for significant difference between dose volume indices of plans.</p> <p><strong>Results: </strong>All VMAT techniques produced clinically acceptable plans for prostate, while for head-and-neck, DA and ISAs significantly improved target coverage compared to SA. Single arc is sufficient for prostate, while inefficient in case of head-and-neck dose-planning. In spite of having different VMAT optimization approach dual arc and two combined independent-single-arcs provided very similar target coverage, while dual arc improved sparing of organs-at-risk. Similar treatment delivery times were observed for DA and ISAs VMAT techniques.</p> <p><strong>Conclusion:</strong> Single arc is sufficient for prostate, while inefficient in case of head-and-neck dose-planning.Dual arc and two combined independent-single-arcs provided similar PTV coverage, while DA provided better sparing of organs at risk. <strong>Continuous...</strong></p>}, number={4}, journal={Journal of the Pakistan Medical Association}, author={Ghulam Murtaza and Zaheer Abbas Gillani and Shahid Mehmood and Jalil Ur Rehman and Ehsan Ullah Khan}, year={2021}, month={Nov.}, pages={1093–1099} }