US Patent 10532224 Offline angle selection in rotational imaging and tracking systems

A processing device determines a plurality of angles from which tracking images can be generated by an imaging device. The processing device generates a plurality of projections of a treatment planning image of a patient, the treatment planning image comprising a delineated target, wherein each projection of the plurality of projections has an angle that corresponds to one of the plurality of angles from which the tracking images can be taken. The processing device determines, for each angle of the plurality of angles, a value of a tracking quality metric for tracking the target based on an analysis of a projection generated at that angle. The processing device selects a subset of the plurality of angles that have a tracking quality metric value that satisfies a tracking quality metric criterion.