Maximum likelihood reconstruction for cone beam SPECT: development and initial tests

Abstract

Owing to the known potential of maximum likelihood reconstruction, the authors have developed a cone beam single photon emission computerised tomography maximum likelihood algorithm in an effort to reduce or remove the reconstruction distortions in cone beam filtered back projection. Previous work (Floyd et al., 1986) was done on cone beam maximum likelihood, but with poor impractical resolution because of practical limitations on computer memory. For the present study, the authors have developed a new implementation which provides higher, potentially practical, resolution by recalculating all matrix elements as needed rather than calculating once and storing in the computer.