Implementation and evaluation of an analytical solution to the photon attenuation and nonstationary resolution reconstruction problem in SPECT

The implementation and evaluation of an analytical solution to the photon attenuation and nonstationary resolution reconstruction problem in single photon emission computed tomography (SPECT). The method, which assumes uniform attenuation, is based on a combination of the Bellini attenuation compensation and Appledom nonstationary resolution correction algorithms. It is termed the simultaneous correction algorithm (SCA). The results of testing the method with point source acquisitions showed a significant improvement in reducing the nonstationary behavior of the collimator response. The ratios of the FWHMs showed better agreement with the ideal value of 1.0, and the MTF”s of the point spread functions exhibited less positional variation when using the SCA over other methods. In addition, the initial quantitative values were restored to acceptable levels.