Accelerating algebraic reconstruction using CUDA-enabled GPU

In this paper, we apply the Compute Unified Device Architecture (CUDA) to the 3D cone-beam CT reconstruction using Simultaneous Algebraic Reconstruction Technique (SART). With the hardware acceleration, the computationally complex SART can run at speed comparable to the commonly used Filtered Back-Projection, and provide even better quality volume with less samples. The main contributions include two novel techniques to accelerate the reconstruction. We introduce a ray-driven projection along with hardware built-in trilinear interpolation, as well as a voxel-driven back-projection that can avoid redundant computation by combining CUDA shared memory. Significant performance boost is reported from experiments using our techniques. A real-time reconstruction is achieved within 3 seconds for a 128³ volume from 80 128² projections, without compromising image quality. Our proposed method realizes the instantaneous presentation of CT volume to the physician once projection images are acquired.