Fig. 3From: Head-to-head comparison of a Si-photomultiplier-based and a conventional photomultiplier-based PET-CT systemThe ratio between the Discovery MI and the Discovery 690 of the spherepeak/backgroundpeak ratio for acquisition times 600–15 s/bed in the cylindrical Jaszczak phantom. The spheres had diameters between 3.95 and 9.89 mm and the phantom was filled with 18F-FDG. The sphere-to-background ratios (SBRs) were 15:1, 7.5:1, and 3.75:1, respectivelyBack to article page