Navigated, robot assisted drilling of a minimally invasive cochlear access

Due to ever increasing requirements of high precision surgery, robotic assistance is becoming an emerging and highly demanded technology. Especially in the field of minimally invasive surgery, missing anatomic landmarks and restricted visibility limit the surgeon's control and thus restrict surgical interventions. In particular cochlear implant (CI) surgery is an example of a procedure, characterized by a high degree of complexity and required accuracy. Using mechatronical devices, solutions are provided for the surgeon to cope with these challenges. This paper presents a minimally-invasive approach to cochlea implantation, using an image guided surgery system (IGS) and a robotic manipulator equipped with a surgical drill. This includes computer assisted 3D-planning of the drill coordinates to ensure a maximum safety margin of the drill canal to the vital parts, such as the facial nerve. In order to determine the system's accuracy, preliminary measurements were done using a laser pointer and a camera based appraisal of laser pointer movements. Finally, the drilling was successfully performed on five cadaveric specimens of the human temporal bone. This contribution presents hardware and software components of this approach as well as the results of the robotic assisted drilling experiments.