Ex-Vivo SPECT Imaging Studies Using the RISE Reconstruction Method

The Reconstructed Image from Simulations Ensemble (RISE) utilizing parametric models describing the physical characteristics of the activity distribution offers a novel image reconstruction method for emission tomography. In this work, the method is evaluated with preclinical SPECT data from small animal imaging experiments. In two ex-vivo studies, two mice were injected with
^99m
Tc-DTPA (renal perfusion) and
^99m
Tc-MAA (pulmonary perfusion) and imaged with a high-resolution γ-camera system. Sinograms varying the number of counts were used to examine the reconstruction capability of RISE. The RISE reconstructed images are compared to those of the Maximum Likelihood Expectation Maximization (MLEM) method via the Contrast-to-Noise Ratio (CNR) and the Coefficient of Variation (CV) where RISE is shown to yield images of superior quality.