Comparison of scatter compensation strategies for cardiac perfusion imaging using Tc-99m labeled sestamibi

Scatter can be a confounding problem in the detection of perfusion defects in cardiac perfusion imaging. The goal of this investigation was to compare practical methods of scatter compensation representing different classes of compensation strategies. The methods investigated were: 1) modification of the energy window; 2) use of effective as values of attenuation coefficients; 3) estimating the scatter distribution from energy spectrum information; and 4) estimating the scatter distribution in the spatial domain using the attenuation maps and scatter kernels. Monte Carlo simulated projections from two MCAT source distributions were used to investigate the impact of the various methods on residual scatter and cardiac uniformity. The investigation showed that each of the methods reduce the scatter significantly; however, the spatial domain method gave the least variation with the different source distributions and the best uniformity.