An Analytical Approach of Compensation for Non-Uniform Attenuation and 3D Detector Response in Cardiac SPECT Imaging

Abstract

Photon attenuation and the non-stationary detector response can reduce the diagnostic accuracy of cardiac SPECT imaging. In this paper, we present a non-iterative approach for compensation of non-uniform attenuation and the 3D detector response in reconstructing cardiac SPECT images. The method involves combining Bellini’s attenuation compensation method using a non-uniform attenuation map, with a frequency distance principle (FDP) based restoration filter to account for the 3D distance-dependent detector response. Simulations using a mathematical cardiac-torso phantom were conducted to obtain projection sets with attenuation only, and attenuation and 3D distance-dependent detector response. “Bulls-eye” polar maps of the reconstructed images showed that using the Bellini method with a nonuniform attenuation map provided quantitatively accurate reconstructions of the myocardium. Applying the combined Bellini/FDP filtering approach to projections degraded by attenuation and distance-dependent blurring also provided quantitatively accurate reconstructions of the myocardium. The Bellini and FDP restoration filtering methods can be implemented with computation times suitable for routine clinical use.KeywordsCount DensityHeart RegionInverse FilterCardiac SPECTAttenuation CompensationThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.