Evaluation of a commercial Monte Carlo dose calculation algorithm for electron treatment planning.

Evaluation of a commercial Monte Carlo dose calculation algorithm for electron treatment planning.
J Appl Clin Med Phys. 2019 May 23;:
Authors: Huang JY, Dunkerley D, Smilowitz JB
Abstract
The RayStation treatment planning system implements a Monte Carlo (MC) algorithm for electron dose calculations. For a TrueBeam accelerator, beam modeling was performed for four electron energies (6, 9, 12, and 15 MeV), and the dose calculation accuracy was tested for a range of geometries. The suite of validation tests included those tests recommended by AAPM's Medical Physics Practice Guideline 5.a, but extended beyond these tests in order to validate the MC algorithm in more challenging geometries. For MPPG 5.a testing, calculation accuracy was evaluated for square cutouts of various sizes, two custom cutout shapes, oblique incidence, and heterogenous media (cork). In general, agreement between ion chamber measurements and RayStation dose calculations was excellent and well within suggested tolerance limits. However, this testing did reveal calculation errors for the output of small cutouts. Of the 312 output factors evaluated for square cutouts, 20 (6.4%) were outside of 3% and 5 (1.6%) were outside of 5%, with these larger errors generally being for the smallest cutout sizes within a given applicator. Adjustment of beam modeling parameters did not fix these calculation errors, nor does the planning software allow the user to input correction ...

Source: Journal of Applied Clinical Medical Physics - May 22, 2019 Category: Physics Authors: Huang JY, Dunkerley D, Smilowitz JB Tags: J Appl Clin Med Phys Source Type: research