Simultaneous correction of attenuation and detector response was implemented in Single Photon Emission Computed Tomography (SPECT) image reconstruction. We have developed a ray-driven projector-backprojector which exactly models attenuation in the reconstructed image slice and the spatially variant detector response. The projector-backporojector was used in the iterative maximum likelihood algorithm to simultaneously correct for nonuniform attenuation and detector response. A computer generated heart-lung phantom was used in simulation studies to compare the simultaneous correction method with the intrinsic attenuation correction method with a smoothing filter, the intrinsic attenuation correction method with a deconvolution filter, and a modified Chang attenuation correction method which uses nonuniform attenuation distribution. The results demonstrate that the simultaneous correction method using the iterative maximum likelihood algorithm provides more accurate quantitation and superior image quality compared to the other correction techniques tested.
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Nuclear Energy and Engineering
- Electrical and Electronic Engineering