Comparisons motion correction methods for PET studies

Motion in PET studies degrades the image quality and introduces bias which is critical for high resolution scanners such as mCT, mMR, and HRRT. There are many publications related to motion correction in PET. They consider either Rigid-body or Non Rigid-body motion and use three methods for motion correction. In this work we will describe and compare three motion correction methods. The first method performs motion correction in image space, while the second method performs motion correction in sinogram (or LOR) space and then reconstruct the motion corrected sinogram. The third method performs motion correction during the reconstruction process. Amongst the three methods, one should be selected depending on the amount of motion, the selected isotope, and the application: brain, cardiac, or whole body. In this work, three rigid body motion correction methods are compared for brain application.