Distributed MLEM: An Iterative Tomographic Image Reconstruction Algorithm for Distributed Memory Architectures

作者：Cui Jingyu; Pratx Guillem; Meng Bowen; Levin Craig S^*

来源：IEEE Transactions on Medical Imaging, 2013, 32(5): 957-967.

DOI：10.1109/TMI.2013.2252913

• Compute unified device architecture (CUDA)
• graphics processing unit (GPU)
• high performance computing
• list-mode
• maximum likelihood expectation maximization (MLEM)
• parallel computing
• positron emission tomography (PET) image reconstruction

The processing speed for positron emission tomography (PET) image reconstruction has been greatly improved in recent years by simply dividing the workload to multiple processors of a graphics processing unit (GPU). However, if this strategy is generalized to a multi-GPU cluster, the processing speed does not improve linearly with the number of GPUs. This is because large data transfer is required between the GPUs after each iteration, effectively reducing the parallelism. This paper proposes a novel approach to reformulate the maximum likelihood expectation maximization (MLEM) algorithm so that it can scale up to many GPU nodes with less frequent inter-node communication. While being mathematically different, the new algorithm maximizes the same convex likelihood function as MLEM, thus converges to the same solution. Experiments on a multi-GPU cluster demonstrate the effectiveness of the proposed approach.

• 出版日期2013-5