Reconstruction of cardiac-gated dynamic SPECT images

In this work, we propose an image reconstruction procedure which will unify gated SPECT and dynamic SPECT into a single imaging method. Traditionally, gated SPECT and dynamic SPECT are treated as two distinct directions in SPECT imaging: gated SPECT aims to reconstruct a periodic stationary sequence of the cardiac cycle, while dynamic SPECT aims to obtain a time-varying distribution of the radiolabeled tracer during the study. In the proposed reconstruction procedure, we divide the cardiac cycle into a number of gate intervals as in gated SPECT, but treat the tracer distribution for each gate as a time-varying signal. By using list-mode data, this procedure produces an image sequence that shows both cardiac motion and time-varying tracer distribution. To demonstrate the proposed method, we simulated gated cardiac perfusion imaging with Tc-99m labeled Teboroxime using the 4D gated mathematical cardiac-torso (gMCAT) phantom. Preliminary results are presented to demonstrate the feasibility of the proposed approach.