Impact of motion on indirect and direct reconstruction of kinetic parameters from dynamic PET data

Clinical PET imaging of the abdomen and thorax rely on standardised uptake values using static imaging but more robust quantification can be performed using dynamic protocols and estimating kinetic parameters from the dynamic PET data. However quantitative parameters both in static and dynamic imaging suffer from patient motion. In dynamic imaging the motion-induced data blurring and emission-attenuation mismatch results in erroneous time-activity curves potentially leading to erroneous parametric maps. Furthermore the effects of motion on direct parameter estimates using 4D image reconstruction algorithms are not known. In this work using a novel 5-D numerical body phantom we evaluate the impact of body motion on kinetic parameters in dynamic abdominal and thoracic PET imaging. Furthermore we compared parameter estimates obtained using both conventional post-reconstruction analysis as well as direct 4D image reconstruction.