Image reconstruction methods for I-123 DaTscan imaging using a multi-pinhole and fan collimator dual-headed SPECT system

We investigate iterative image reconstruction strategies for clinical I-123 DaTscan imaging on a dual-headed mixed collimator SPECT system consisting of fan and multi-pinhole (MPH) collimators on separate heads. DaTscan is used for the diagnosis and monitoring progression of Parkinson´s Disease (PD). The current system was proposed in [1] for high-resolution imaging of activity in the structures of interest: the putamen (P), caudate (C) and potentially substantia nigra (SN) which lie in the central interior portion of the brain. However imaging of the occipital lobe is also required with PD for calculation of the striatal binding ratios (SBR), a parameter of significance in the early diagnosis, and differentiation of PD from other disorders with similar clinical presentations, and monitoring progression [2]. In this work we present different strategies for image reconstruction using resolution and sensitivity modeling of both fan and MPH collimators. The reconstruction output from Fan and MPH collimators individually are compared to the outputs of combined reconstruction strategies for visual quality and accuracy of SBRs.