FPGA Implementation of EM Algorithm for 3D CT Reconstruction

Although the expectation maximization (EM)based 3D computed tomography (CT) reconstruction algorithm lowers radiation exposure, its long execution time hinders practical usage. To accelerate this process, we introduce a novel external memory bandwidth reduction strategy by reusing both the sinogram and the voxel intensity. Also, a customized computing engine based on field-programmable gate array (FPGA) is presented to increase the effective memory bandwidth. Experiments on actual patient data show that 85X speedup can be achieved over single-threaded CPU.