“…The well studied ML‐EM algorithms have been found to produce good results in reconstruction from noisy data as they are based on Poisson statistics (Shepp and Vardi,1982; Unser and Eden,1988; Liow and Strother,1991; Barrett et al,1994; Qi,2003; Hwang and Zeng,2006a). Nevertheless, the ML‐EM algorithm still suffers from noise, and many attempts have been made to further reduce this statistical noise (Hebert and Leahy,1989; Green,1990; Liow and Strother,1991; Johnson,1994; Panin et al,1999; Selivanov et al,2001; Nuyts,2002; Nuyts and Fessler,2003; Hwang and Zeng,2005). This article shows that the use of sub‐sinograms can contribute to the reduction of noise within a reconstructed image.…”