A GPU-based finite-size pencil beam algorithm with 3D-density correction for radiotherapy dose calculation
Center for Advanced Radiotherapy Technologies and Department of Radiation Oncology, University of California San Diego, La Jolla, CA 92037-0843, USA
arXiv:1103.1164 [physics.med-ph] (6 Mar 2011)
@article{2011arXiv1103.1164G,
author={Gu}, X. and {Jelen}, U. and {Li}, J. and {Jia}, X. and {Jiang}, S.~B.},
title={“{A GPU-based finite-size pencil beam algorithm with 3D-density correction for radiotherapy dose calculation}”},
journal={ArXiv e-prints},
archivePrefix={“arXiv”},
eprint={1103.1164},
primaryClass={“physics.med-ph”},
keywords={Physics – Medical Physics},
year={2011},
month={mar},
adsurl={http://adsabs.harvard.edu/abs/2011arXiv1103.1164G},
adsnote={Provided by the SAO/NASA Astrophysics Data System}
}
Targeting at developing an accurate and efficient dose calculation engine for online adaptive radiotherapy, we have implemented a finite size pencil beam (FSPB) algorithm with a 3D-density correction method on GPU. This new GPU-based dose engine is built on our previously published ultrafast FSPB computational framework [Gu et al. Phys. Med. Biol. 54 6287-97, 2009]. Dosimetric evaluations against MCSIM Monte Carlo dose calculations are conducted on 10 IMRT treatment plans with heterogeneous treatment regions (5 head-and-neck cases and 5 lung cases). For head and neck cases, when cavities exist near the target, the improvement with the 3D-density correction over the conventional FSPB algorithm is significant. However, when there are high-density dental filling materials in beam paths, the improvement is small and the accuracy of the new algorithm is still unsatisfactory. On the other hand, significant improvement of dose calculation accuracy is observed in all lung cases. Especially when the target is in the middle of the lung, the accuracy improvement with the 3D-density correction is dramatic. Regarding the efficiency, because of the appropriate arrangement of memory access and the usage of GPU intrinsic functions, the dose calculation for an IMRT plan can be accomplished well within 1 second (except for one case) with this new GPU-based FSPB algorithm with 3D-density correction. Compared to the previous GPU-based FSPB algorithm, this 3D-density correction FSPB algorithm, though slightly scarifying its computational efficiency (~5-15% lower), has significant improvement of dose calculation accuracy, indicating that this new algorithm is more suitable for online IMRT replanning.
March 8, 2011 by hgpu
