TABLE 2.

RMSE, PSNR, and SSIM for SIPs and SPECT Images in Test Group

Image type	RMSE	PSNR	SSIM
SIPs	2.95 (0.77)	39.2 (3.8)	0.926 (0.061)
AC-OSEM 30 projections	0.147 (0.060)	47.2 (3.5)	0.989 (0.008)
AC-OSEM 30–120SIPs	0.109 (0.044)*	49.5 (3.3)*	0.993 (0.005)*
ASCC-OSEM 30 projections	0.259 (0.101)	49.0 (3.5)	0.993 (0.005)
ASCC-OSEM 30GF projections	0.273 (0.162)	48.3 (2.5)	0.995 (0.004)†
ASCC-OSEM 30–120SIPs	0.195 (0.091)*	50.8 (3.2)*	0.996 (0.003)*

^*P < 0.001.

^†P < 0.01.

GF = gaussian postfilter, SD of 4 mm.

Data in parentheses are SDs.