Patient motion quantification from tomographic data

The authors have developed an automatic procedure for the detection, quantification and correction of translational motion during tomographic acquisition. The method computes the optical flow vector field between two successive views. The optical flow vector field assigns to each pixel of a tomographic view a two dimensional velocity that describes its motion across the image plane between two successive views. The average optical flow of a region of interest is when computed to measure its interview global motion. Motion is corrected by shifting back the views where motion is detected by the amount of the predicted motion distance. The method is applied to simulated and patient tomographic raw data in single photon emission computed tomography (SPECT). Visually artifactual perfusion defects are eliminated. The optical flow method can accurately detect the presence of motion, localize the camera angle at which motion occurred and measure the distance of motion