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arXiv · 0908.4417

GPU-based ultra fast dose calculation using a finite pencil beam model

Xuejun Gu·Dongju Choi·Chunhua Men·Hubert Pan·Amitava Majumdar·Steve B. Jiang
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Abstract

Online adaptive radiation therapy (ART) is an attractive concept that promises the ability to deliver an optimal treatment in response to the inter-fraction variability in patient anatomy. However, it has yet to be realized due to technical limitations. Fast dose deposit coefficient calculation is a critical component of the online planning process that is required for plan optimization of intensity modulated radiation therapy (IMRT). Computer graphics processing units (GPUs) are well-suited to provide the requisite fast performance for the data-parallel nature of dose calculation. In this work, we develop a dose calculation engine based on a finite-size pencil beam (FSPB) algorithm and a GPU parallel computing framework. The developed framework can accommodate any FSPB model. We test our implementation on a case of a water phantom and a case of a prostate cancer patient with varying beamlet and voxel sizes. All testing scenarios achieved speedup ranging from 200~400 times when using a NVIDIA Tesla C1060 card in comparison with a 2.27GHz Intel Xeon CPU. The computational time for calculating dose deposition coefficients for a 9-field prostate IMRT plan with this new framework is less than 1 second. This indicates that the GPU-based FSPB algorithm is well-suited for online re-planning for adaptive radiotherapy.

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Xuejun Gu, Dongju Choi, Chunhua Men, Hubert Pan, Amitava Majumdar, Steve B. Jiang. 2009-08-30. GPU-based ultra fast dose calculation using a finite pencil beam model. https://doi.org/10.1088/0031-9155/54/20/017

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