Motion correction for jPET-D4: improvement of measurement accuracy with a solid marker

We proposed a unique motion detection method that can be used for motion correction in brain PET imaging. This method uses a specially-designed solid marker that enables position and angle (direction) measurement with one optical movie camera. Therefore, it is applicable to a long, narrow patient port space in which a two-camera system cannot be installed. By refining machining accuracy of the solid marker, angle measurement accuracy was significantly improved. As a result, we obtained sufficient measurement accuracies in the angles as well as in the trans-axial positions. In addition, we have been developing a model to calculate axial positions from measured trans-axial positions and angles. As a result of a multivariate analysis of measured motion tracking data, we found that sufficient accuracy can be obtained under well-controlled experimental conditions. In order to realize head motion correction for jPET-D4, we are also considering marker attaching, camera calibration, device installation, and correction algorithms.