Single-photon emission computed tomography (SPECT) is the leading medical-imaging method for the study myocardial perfusion, which is important for the diagnosis and treatment of coronary-artery disease, the number-one killer in the western world. C-SPECT is a proposed dedicated cardiac SPECT system designed to achieve at least double the geometric efficiency compared to general-purpose dual-head gamma cameras, for the same resolution. This improvement can be used to reduce patient radiation dose, achieve fast or dynamic imaging, and enhance the quality of images. The system consists of stationary detector modules of pixelated NaI(Tl), a slit-slat collimator with interchangeable slits and collapsible slats, and an integrated CT for attenuation correction. The collimator slits provide pinhole collimation in the transverse plane, whereas the slats offer parallel-beam collimation in the axial direction. The adaptive power of the collimator allows us to adjust, in situ, the sensitivity and resolution depending on the imaging task. This way, superior reconstructed-image resolution could be achieved if the system operates with the usual geometric efficiency of the industry's benchmark. The system gantry wraps around patients' left-front thorax and provides a transverse projection minification of ~50%, for a maximal number of minimally-overlapping projections, given the limitations from the spatial resolution of the pixelated detector. We present the design principles and preliminary imaging performance using three-dimensional iterative reconstruction with resolution recovery and data from the newly-built laboratory prototype as well as Monte-Carlo (MC) simulations of the full system.

This work was supported by NIH grant HL108119 and utilized resources provided by the Open Science Grid, which is supported by the National Science Foundation and the U.S. Department of Energy's Office of Science.