Room: ePoster Forums
Purpose: Jaws-only intensity modulated radiotherapy (JO-IMRT) is an alternative technique for a linac without multileaf collimator (MLC) system in IMRT delivery. This study verified the JO- IMRT treatment plan created by the Prowess Panther treatment planning system (TPS), by comparing the dose distribution between the TPS and Monte Carlo simulation based on AAPM TG-119 test instructions.
Methods: The Siemens Primus linac was modeled using the EGSnrc-based BEAMnrc code and validated using IBA blue phantom experimentally. JO-IMRT plans were created by the Prowess Panther TPS using the Collapsed Cone Convolution dose calculation algorithm for a set of test cases, namely, multi-target, mock prostate, mock head-and-neck and C-shape. They were compared with the Monte Carlo-calculated dose distributions using 3D gamma index according to global methods implemented in the PTW-VeriSoft with criteria equal to 3%/3 mm.
Results: JO-IMRT plans using TG-119 structure sets agreed well with the Monte Carlo dose distributions. The gamma index passing rates were 98.9% for multi-target, 97.6% for mock prostate, 95% for mock head-and-neck, and 96.4% for C-shape.
Conclusion: TPS-calculated JO-IMRT dose distributions agreed with Monte Carlo simulation based on AAPM TG-119.