A method of automatic registration, comprising: obtaining image data of a medical device, the medical device comprising a plurality of fiducial markers arranged as a fiducial frame on the medical device, said fiducial frame comprising: at least three fiducial markers arranged in a ring shape, wherein their arrangement is asymmetric; detecting fiducial marker objects within the image data by: applying a feature enhancement to the image data to enhance the fiducial marker objects, the feature enhancement including shape data of the fiducial markers, applying a feature extraction based on the shape data of the fiducial markers to extract the fiducial marker objects; defining a representative point for each extracted fiducial marker object; and registering the fiducial marker objects with a model of the fiducial frame, the registering step comprising: for image data of the at least three fiducial markers arranged in the ring shape, rotating the ring shape until the representative points of the fiducial marker objects match the model of the fiducial frame, characterized in that the medical device further comprises: a base adapted to be placed on a body surface; and an opening to provide visual and physical access to the body surface through the medical device, wherein the fiducial markers are arranged in the ring shape on the base that surrounds the opening in the medical device, at least three fiducial markers arranged in a ring shape, wherein their arrangement is asymmetric; detecting fiducial marker objects within the image data by: applying a feature enhancement to the image data to enhance the fiducial marker objects, the feature enhancement including shape data of the fiducial markers, applying a feature extraction based on the shape data of the fiducial markers to extract the fiducial marker objects; defining a representative point for each extracted fiducial marker object; and registering the fiducial marker objects with a model of the fiducial frame, the registering step comprising: for image data of the at least three fiducial markers arranged in the ring shape, rotating the ring shape until the representative points of the fiducial marker objects match the model of the fiducial frame, characterized in that the medical device further comprises: a base adapted to be placed on a body surface; and an opening to provide visual and physical access to the body surface through the medical device, wherein the fiducial markers are arranged in the ring shape on the base that surrounds the opening in the medical device, applying a feature enhancement to the image data to enhance the fiducial marker objects, the feature enhancement including shape data of the fiducial markers, applying a feature extraction based on the shape data of the fiducial markers to extract the fiducial marker objects; defining a representative point for each extracted fiducial marker object; and registering the fiducial marker objects with a model of the fiducial frame, the registering step comprising: for image data of the at least three fiducial markers arranged in the ring shape, rotating the ring shape until the representative points of the fiducial marker objects match the model of the fiducial frame, characterized in that the medical device further comprises: a base adapted to be placed on a body surface; and an opening to provide visual and physical access to the body surface through the medical device, wherein the fiducial markers are arranged in the ring shape on the base that surrounds the opening in the medical device, for image data of the at least three fiducial markers arranged in the ring shape, rotating the ring shape until the representative points of the fiducial marker objects match the model of the fiducial frame, characterized in that the medical device further comprises: a base adapted to be placed on a body surface; and an opening to provide visual and physical access to the body surface through the medical device, wherein the fiducial markers are arranged in the ring shape on the base that surrounds the opening in the medical device, a base adapted to be placed on a body surface; and an opening to provide visual and physical access to the body surface through the medical device, wherein the fiducial markers are arranged in the ring shape on the base that surrounds the opening in the medical device,