A New Architecture for Pixellated solid state gamma camera used in nuclear medicine

The general object of the present publication is to provide a novel technique for acquisition and reconstruction of planar or tomographic images obtained by gamma camera. The objective is to overcome sensitivity - spatial resolution tradeoff of conventional Anger gamma camera. In this framework, the future generation of solid state gamma camera will take benefit of recent CdZnTe (CZT) detector performances. Previous works show that pixellated CZT detectors have high energy resolution, good detection efficiency and high intrinsic spatial resolution. Moreover, these detectors provide important additional information: the depth of interaction (DOI). In this paper, we present HiSenstrade (High Sensitivity) architecture: an original architecture of collimator associated to CZT pixellated detector that takes advantages of such performances and particularly DOI information. First, we detail the experimental results of DOI accuracy on a 5 mm thick CZT detector. Second, we present the validation of the simulation tool (SINDBAD), in order to estimate performances combining new architecture and new solid state detectors. Third, we describe an adapted iterative reconstruction using the DOI information to improve image quality. At last, preliminary results of HiSens architecture performances are presented.