A cerebral instrument guide includes first and second arcs with aligned openings adjacent their ends, the openings defining a common axis about which the arcs are pivotal. The rods are mounted for movement along the common axis into contact with a human patient's auditory meati. A nasal bridge fixation...http://www.google.com/patents/US5330485?utm_source=gb-gplus-sharePatent US5330485 - Cerebral instrument guide frame and procedures utilizing it
