Concept and evaluation of a synergistic controlled robotic instrument for trepanation in neurosurgery

A robotic instrument which synergistically cooperates with the surgeon for opening the skull in neurosurgery is proposed. To reduce frequent complications of this intervention, tear of the dura mater and bad reintegration of the skull bone a soft tissue preserving saw is combined with automatic depth regulation on the basis of a priori acquired medical imaging data (CT/MRI). By fusing the individual capabilities of the surgeon and a robotic device, it is possible to design an instrument which is significantly smaller than a fully autonomous system. The acceptance is enhanced by the integration of the surgeon into the process with direct control over the procedure. During the intervention, the instrument is manually guided by the surgeon on a freely defined trajectory. To be able to control this instrument, a method for real-time depth regulation, medical imaging data pre-processing and reduction as well as appropriate interfaces for the surgeon have been developed. In an experimental setup with phantom skull caps the system has been evaluated and has shown promising results, with a mean error of 0.62mm. Future work will include a detailed analysis of the persisting errors, integration of different sensors to control the instrument and preclinical trials.