Software Solutions for Nuclear Imaging Systems in Cardiology, Small Animal Research and Education

Sammanfattning: The sensitivity for observing physiological processes makes nuclear imaging an important tool in medical diagnostics. Different types of nuclear imaging modalities, with emphasis on the software components and image reconstructions, are presented in this thesis:  the Cardiotom for myocardial heart studies at the Karolinska University Hospital, the small animal Positron Emission Tomograph (PET) scanners for research and the SPECT, PET, spiral CT and Cardiotom demonstrators for the Royal Institute of Technology medical imaging laboratory.A modular and unified software platform has been developed for data representation, acquisition, visualization, reconstruction and presentation of the programs of the imaging devices mentioned above. The high performance 3D ML-EM and OS-EM iterative image reconstruction methods are implemented both on Cardiotom and miniPET scanners.As a result, the in-slice resolution of the first two prototypes of the Cardiotom today is the same as the formerly used filtered back-projection, however the in-depth resolution is considerably increased. Another improvement due to the new software is the shorter time that is required for data acquisition and image reconstruction. The new electronics with the newly developed software ensure images for medical diagnosis within 10 minutes from the start ofthe examination. The first system from the standardized production of the Cardiotom cameras is in the test phase.The performance parameters (sensitivity, spatial and energy resolution, coincidence time resolution) of the full ring mini PET camera are comparable to other small animal PETsystems.