Mechatronic Assistance System for High-Precision Cranial Surgery

• Applicants: Professor Dr. Omid Majdani; Professor Dr.-Ing. Tobias Johannes Ortmaier
• Subject Area: Automation, Mechatronics, Control Systems, Intelligent Technical Systems, Robotics
• Term: from 2010 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 190590330

Precision skull surgery requires specialized instrumentation to satisfy demanding requirements with respect to accuracy and minimal invasiveness. In this context, cochlear implantation, which has been established as the standard treatment for patients suffering from severe hearing loss or deafness, serves as a benchmark application. The common surgical procedure involves the insertion of an electrode carrier into the cochlea in order to electrically stimulate the auditory nerve. In order to minimize operative time, postoperative trauma, as well as convalescence time for patients, a minimally invasive approach to cochlear implantation is proposed. However, this requires the surgical opening of the Cochlea (Cochleostomy) to be performed with an accuracy better than 0.5 mm. The aim of this project is to develop a novel, highly accurate operative technique with possible applications in several surgical fields. Within this project, a mechatronic device providing the surgeon with a highly accurate linear guidance for instruments is being designed, built and evaluated. The proposed concept is based on a passive parallel robot which can be directly attached to the patient´s skull. Here, preoperatively placed bone anchors with spherical heads serve as base points of the kinematics. The same spherical heads are used as fiducials during the task planning. Thus, intraoperative navigation as well as erroneous point-based registration is no longer required. As a result, the surgical workflow is expected to be significantly simplified. The development of the versatile mechatronic device further includes a theoretical approach to the determination of all relevant error sources leading to deviations from the surgical planning. The achievable accuracy will be evaluated experimentally. Finally, the aim is to prove the capabilities of the proposed concept under clinically-like boundary conditions.

• DFG Programme: Research Grants