Fig. 3
From: The magnitude of the partial volume effect in SPECT imaging of the kidneys: a phantom study
SPECT/CT images of kidney phantoms. SPECT/CT images of the phantoms Pat10L (whole-parenchyma) and Pat1R (cortex only) acquisitions. The phantoms were filled with a 10:1 target-to-background ratio. The volume of interest (VOI) was defined as the isocontour on the CT image (A) in such a way that all voxels inside the phantom were included. The threshold of the isocontour was adjusted so that the volume of the VOI was as close as possible to the actual filling volume of the phantoms. The thresholds for VOI1 and VOI3 were 88%. The VOI was subsequently transferred to the SPECT image (B) to determine the recovery coefficient of the phantom