A small animal helical SPECT scanner

Small animal imaging relies on cone-beam reconstruction geometries to achieve high spatial resolution for both microSPECT and microCT. However, normal circular-orbit cone-beam geometries offer a restricted field of view which for microSPECT has nonuniform sensitivity and spatial resolution. These limitations can be addressed by using a more complex detector orbit such a helix. In this paper, we present a small animal helical SPECT system which uses CZT detectors to acquire radionuclide data with excellent energy resolution and spatial resolution. It incorporates a gantry with integrated slip-ring for continuous detector rotation and an automated animal bed for translation. Both simulation studies and experimental data show this scanner improves the axial spatial resolution and lengthens the field of view in the axial direction