THE FAVOR ALGORITHM FOR 3D PET DATA AND ITS IMPLEMENTATION USING A NETWORK OF TRANSPUTERS

The recent appearance of septa-retractable positron emission tomography (PET) scanners has created a demand for fast three-dimensional (3D) reconstruction. While algorithms based on filtered backprojection have been developed to reconstruct PET data acquired in 3D (volume mode), they are computationally intensive owing to the large numbers of coincidence lines and image voxels that must be processed. Such linear algorithms are well suited to parallel implementation on a network of individual processors. In this paper, we present an algorithm for fast volume reconstruction (FAVOR) of PET data, and describe its parallel implementation on a network of 44 T800 transputers. A reconstruction time of 1200 s has been achieved with this configuration of 44 T800 transputers comparable to that required by a single i860 processor. The prospects exist for 3D reconstruction times of around 120 s with the new generation of T9000 transputers which should become available in the near future.