Distributed navigated control for active instruments in a real-time networked operating room

With the patented method of Navigated Control active surgical instruments can be stopped before they endanger delicate and sensitive tissue such as nerves and vessels. To this end, a stereo camera tracks the positions of instrument and patient, a computer then measures the distance to the patient structure and calculates the allowed output power for the instrument. This clinically approved principle requires different systems to exchange data with hard timing constraints. The German research project OR.NET aimed at enabling interoperability of medical devices with a real-time capable network architecture. In this contribution we show how the Navigated Control principle can be applied to various different devices and how it can be integrated into a real-time medical device network based on that architecture. Distributed Navigated Control has the potential to facilitate the integration process for further active instruments and to enable a highly modular system-of-systems. We successfully implemented Distributed Navigated Control for a surgical drill and for the first time for an ultrasonic aspirator. The respective output power of both devices can be limited via the network simultaneously and with hard timing constraints.