ROBOTICS IN SURGERY

Surgery now uses robotic and image processing systems in order to interactively assist the medical team, both in planning the surgical intervention, and in its execution. The objective of this new technique is to enhance the quality of surgical procedures by minimizing their side effects (smaller incisions, lesser trauma, more precision,...), thus increasing patient benefit while decreasing the surgical cost. These techniques are being successfully introduced in several areas of surgery: neurosurgery, orthopaedics, micro-surgery, cardiovascular and general surgery etc.

Three main steps can be pointed out in a general robotic surgery intervention: data acquisition and subsequent planning, intra operative assistance, and post-operative patient control. In the pre-operative phase, a patient dependent model of the rigid (eg bones), and de-formable (eg the heart) anatomical entities involved in the surgical act have to be built. For this, several medical imagery techniques (MRI, Scanner, Ultrasonics, etc.) are used, where the anatomical structures are detected, located and modelled. In the same time, the mechanical model of the robotic system is fused in an overall geometric model. This will be used to describe and simulate the different potential problems that may occur during the intervention.



The results obtained in the planning phase are then calibrated and put in correspondence with patient in intra-operative situation. As a consequence, the robotic system is able to provide interactive assistance/guidance, and to constrain the movements of the surgeon in order to perform, with the desired precision, the possibly pre-defined procedure (eg neuro-surgical biopsy). In some cases, the robot may have an autonomous behaviour in order to realize a dedicated and fixed part of the procedure (eg thighbone drilling for artificial hip installation).

As for tele-operated robots, the surgeon through a master console benefits from an enhanced (sometimes 3D) vision of the organs. In addition, augmented reality would allow the overlay, in real-time, of the pre-operative data of the patient during the intervention. The surgeon movements may be reduced to increase precision, and smoothed to avoid hand tremor by virtue of a decoupled master/slave unit.