Uncertainty Analysis in 3D SPECT Reconstruction based on Probabilistic Programming

Abstract: Single Photon Emission Computed Tomography (SPECT) is one of the nuclear medicine imaging modalities used for functional analysis of animal and human organs. Gamma rays emitted from the scanned body are filtered with collimators and detected by the SPECT head that is composed of an array of gamma detectors. The conventional reconstruction algorithms do not deem the uncertainty level that is associated with the field of view of SPECT collimators. In this paper, we incorporate the probabilistic programming approach for SPECT image reconstruction. No-U-Turn Sampler (NUTS) is used to estimate the scanned object system by considering uncertainty. The obtained results indicate that the presented work in 3D SPECT image reconstruction surpassed over the conventional reconstruction methods in terms of generating uncertainty information. However, the reconstruction time needs to be improved further for phantom sizes of 128x128x128 voxels and higher.