Figure 7.

Radioactivity restoration for the objects with different sizes in the phantom experiment. The true activity was measured from the mean PET intensity within the center sphere with a radius of 5 mm, which is a homogeneous region with minimal partial volume effect. The objects were selected from different slices of the sphere object in the phantom MR image and they were in circular shapes with different diameters when the image slice was selected at different positions. This is to demonstrate the partial volume correction with respect to object sizes. Mean activity of the selected region before and after correction was shown and is also compared with the true intensity.