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

TL;DR

This paper presents a GPU-accelerated finite pencil beam algorithm for ultra-fast dose calculation in adaptive radiation therapy, enabling real-time plan re-optimization with significant speed improvements.

Contribution

It introduces a GPU-based dose calculation engine using a finite-size pencil beam model, achieving rapid computation suitable for online adaptive radiotherapy.

Findings

Achieved 200-400x speedup over CPU implementation.

Dose calculation for a prostate IMRT plan takes less than 1 second.

Framework accommodates any finite pencil beam model.

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.