Myocardial perfusion imaging with an ultra-fast cardiac SPECT camera - a phantom study

Myocardial perfusion imaging is currently the most frequently used nuclear medicine test. Recently, several alternative approaches to myocardial perfusion SPECT imaging have been evaluated. In this study, we compare imaging capabilities of the new ultra-fast cardiac (UFC) system developed by GE Healthcare to a conventional cardiac SPECT camera (Ventri, GE Healthcare). The UFC system uses an array of Cadmium Zinc Telluride (CZT) pixilated detectors simultaneously imaging all cardiac views with no moving parts during acquisition. High system sensitivity together with high intrinsic resolution of the CZT detectors allow acquiring high quality SPECT studies within short time. Image data were acquired experimentally using a Data Spectrum anthropomorphic torso phantom and simulating realistic male and female anatomy, uptake distribution and perfusion defect variations typical for rest and stress Tc99m imaging. Post-reconstruction, estimated count values on the mid-myocardial surface were assessed to calculate the normalized standard deviation (NSD) for the uniform (healthy) myocardium and the normalized contrast (NC) for known defect volumes. Segmental uptake for a 17-segment heart model was used to calculate agreement between reconstructed distributions obtained with the novel and conventional systems.