Fig. 11
From: Respiratory motion correction of PET using MR-constrained PET-PET registration
A case in which image quality deteriorates after unconstrained PET-PET registration based motion correction. Here, the PT method has failed to recover a small lesion in position 9 of volunteer 1. As can be seen, a small, indistinct lesion is indicated by an arrow in the UC image. This is clearly recovered using our method (IC) to a visual quality comparable to the motionless case. However, unconstrained registration (PT) has actively made the lesion harder to see, with two possible candidates indicated by arrows. These are comparable to the levels of noise seen elsewhere in the liver, and could easily be missed. All images are shown on the same intensity scale