University of Cincinnati Medical Center/Cincinnati Children's Hospital, Cincinnati, OH, USA

■ OBJECTIVES: Our robotics research group has performed several robot-assisted cadaveric temporal bone procedures, including: cochleostomies, stapedectomies, and retrosigmoid internal auditory canal decompressions. We wanted to validate whether our open architecture, 7 degree of freedom robotic arm can drill a cochlear implant well in an autonomous fashion to better understand the complexities of adapting robotic technology to temporal bone surgery.

■ METHODS: In a prospective manner, five cadaveric temporal bone specimens were used to perform the experiment. A special fixation stand was created to prevent movement of either the temporal bone itself or of the bone holder. The surgeon controlled suction irrigation and the electric drill. Based on 3 defined fiducial points on the temporal bone (chosen by the surgeon), the well is then created by the robotic arm in an unassisted fashion to a predetermined diameter and depth. After well creation by the robotic arm, the site was inspected by the surgeon with the microscope to ensure accuracy of drilling and to assess for inadvertent injury to surrounding structures.

■ RESULTS: The cochlear implant wells were created in all 5 temporal bones using the robotic system. Nominal velocity of the tool was 2 mm/sec; the well diameter was 16 mm, and depth was 3 mm. The time to completion ranged from 10 to 40 minutes. There was no microscopic evidence of penetration of the inner cortex of the skull. All specimens showed evidence of well creation to the predetermined depth and diameter. Due to the study being for validation of a novel technology and due to the limited number of temporal bone specimens, no statistical evaluation was performed.

■ CONCLUSIONS: Although temporal bone surgery may eventually be performed by robotic assistance, the delicate nature of such an approach, the instruments required, and the limited confines preclude easy adaptation of such technology. Potential benefits of robotic surgery include improved accuracy, reduced surgeon fatigue, tremor reduction, audible proximity warnings, and automatic avoidance behaviors. Future improvements to the surgical robotic system include utilization of three-dimensional cameras /vision systems, incorporation of a haptic feedback handpiece controller, and integration with image guidance systems. *Contact person: Ravi.Samy@UC.edu