US Patent 10420626 Fiducial markers, systems, and methods of registration

Exemplary methods, apparatus, and systems are provided for automated detection and registration of medical images using fiducial markers and processing algorithms. By either clustering fiducial markers having a different number, size, shape, configuration, or material property or by using fiducial markers arranged in a ring shape, wherein their arrangement is asymmetric, and then applying a feature extraction to extract the fiducial marker objects, and registering the fiducial marker objects with a model of the fiducial frame, automatic registration can be achieved.