Fig. 3From: Evaluation of Iodine-123 and Iodine-131 SPECT activity quantification: a Monte Carlo studyNormalised counts and \({\text{SD}}_{{{\text{relative}}}}\) as a function of OS-EM updates for spheres with diameters of 1.5Â cm, 3.0Â cm, 4.5Â cm, and 6.0Â cm, for a 123I LEHR, b 123I ME and c 131I HEBack to article page