A Deconvolution Function for Single Photon Emission Computed Tomography with Constant Attenuation

A shift-invariant spatial deconvolution function for single-photon-emission computerized tomography with constant attenuation is presented. Image reconstruction algorithm is similar to conventional convolution-back-projection algorithm except that exponential weight is applied in backprojection process. The deconvolution function was obtained as a solution of a generalized Schifmilch´s integral equation. A method to solve the integral equation is described briefly. The present deconvolution function is incorporated with frequency roll-off and image resolution can be preset. At the extreme of ideal image reconstruction, the deconvolution function is identical to that deduced by Kim et al. and its Fourier transform was proved to be identical to the filter deduced by Tretiak and Delaney and Gullburg and Budinger. Variance of the reconstructed image was analyzed and some numerical results were given. The algorithm was tested with computer simulation.