Automated Registration for Enhanced Reality Visualization in Surgery

There is a need for frameless guidance systems to aid neurosurgeons in planning the exact lo- cation of a craniotomy, to define the margins of tumors and to precisely locate neighboring criti- cal structures. We have developed an automatic technique for registering clinical data, such as segmented MRI or CT reconstructions, with the actual head of the patient on the operating ts- ble. A second method calibrates the position of a video camera relative to the patient. The combi- nation allows a visual mix of live video of the pa- tient with the segmented 3D MR/or CT model. This registration enables us to employ enhanced reality techniques for planning and guiding nell- rosurgical procedures by merging live video im- ages with the 3D reconstructions, and to inter- actively view extracranial or intracraniai struc- tures in a non-intrusive manner.