Room: ePoster Forums
Purpose: The purpose of this study was to compare automatically generated VMAT plans to find the superior beam configurations for PinnacleÂ³ Auto-Planning and share â€œbest practicesâ€?.
Methods: VMAT plans for 20 patients with head and neck cancer were generated using PinnacleÂ³ Auto-Planning Module (PinnacleÂ³ Version 9.10) with different beam setup parameters. VMAT plans for single (V1) or double arc (V2) and partial or full gantry rotation were optimized. Beam configurations with different collimator positions were defined. Target coverage and sparing of organs at risk were evaluated based on scoring of an evaluation parameter set with 40 DVH parameters. Due to the limited possibilities for fast and scalable DVH comparison within PinnacleÂ³, a new tool for evaluating and comparing DVH parameters was developed.
Results: The evaluation showed a superior plan quality for double arcs compared to one single arc or two single arcs for all cases. Plan quality was superior if a full gantry rotation was allowed during optimization for unilateral target volumes. A double arc technique with collimator setting of 15Â° was superior to a double arc with collimator 60Â° and two single arcs with collimator setting of 15Â° and 345Â°. Using the newly developed DVH comparison tool the approximately 6400 single DVH parameters could be automatically computed and logged for further evaluation.
Conclusion: The evaluation showed that double and full arcs are superior to single and partial arcs in terms of organs at risk sparing even for unilateral target volumes. The collimator position was found as an additional setup parameter, which can further improve the target coverage and sparing of organs at risk. Using automation in DVH evaluation accelerates and eases the process of identifying optimal planning parameters.
Not Applicable / None Entered.