A method for OSEM PET reconstruction on parallel architectures using STIR

To accelerate image reconstruction of positron emission tomography (PET) data, we introduced an approach for parallel architectures by applying the message passing paradigm to an existing implementation of the ordered-subsets expectation-maximization (OSEM) algorithm for two- or three-dimensional (2D/3D) PET. To reduce the amount of time needed to complete a reconstruction, a cluster was used as well as different multi-core systems. A main focus was on the multi-core processors, as these systems are increasingly common and easy to use in medical environments.