Spatio-temporal MAP reconstruction of gated cardiac images using DFT basis functions

Recently we proposed a reconstruction approach for gated cardiac images based on use of DFT basis functions, in which the temporal activity at each spatial location was regulated by a Fourier representation. In this work we further develop this approach in the context of single photon emission computed tomography (SPECT) which is often hampered by the increased noise due to gating. We will consider both attenuation and scattering correction, which are two important degrading factors in SPECT data acquisitions. For reconstruction we apply a maximum a posteriori (MAP) approach to take into account both the data statistics and a Gibbs smoothing prior. The proposed approach is demonstrated using simulated cardiac perfusion imaging based on the 4D NURBS-based cardiac-torso (NCAT) volumetric phantom with TC-99 labeled sestamibi as the imaging agent.