Robots are being increasingly utilized in the medical field. For over 30 years, they have been supporting patient care in healthcare facilities worldwide. Despite this “tradition,” however, the age of medical robotics has only just begun, as a new breed of sensitive and collaborative robots is poised to shape the future of robotics in medicine.

The swiss-based company AOT AG has developed an innovative process for bone surgery, using a KUKA robot that is certified in compliance with the relevant standards.

Identification of the task

The greatest stories are based on real life, as they say – and real life sometimes has a way of coming up with the best innovations. Complex orthodontic surgery undergone by his daughter was the catalyst for a personal meeting between laser researcher Dr. Alfredo E. Bruno and Prof. Dr. Dr. Hans-Florian Zeilhofer, Head of the Oral & Maxillofacial Surgery department of the University Hospital Basel and the Canton Hospital Aarau. The technical exchange of this meeting and the combination of the two areas of competence to create robot-guided laser ablation gave rise to Advanced Osteotomy Tools AG, or AOT for short.

„Our goal was to achieve radical improvement in the results of bone surgery by replacing mechanical cutting instruments with non-contact “cold” laser photoablation and medi-cal robots”, explains Dr. Alfredo E. Bruno, now Chief Scientific Officer (CSO) and member of the administrative board at AOT. To achieve a high precision, the system requires not only the laser and the navigation system, but also a robot. This makes the programmed cuts with millimeter precision and meets the requirements in terms of high sensitivity. For this reason, the path from AOT AG lead to the LBR Med from KUKA.

Solution

Their joint brainchild was given the name CARLO, which stands for Cold Ablation, Robot-guided Laser Osteotome. How does CARLO work? The surgeon carries out the preopera-tive planning on the basis of data from a CT scan and feeds it into CARLO’s navigation system. An intuitive app guides the surgeon and technical staff through CARLO’s initiali-zation step by step. The robot then performs the operation independently. If anything does not go as planned, the physician merely has to touch the robot gently and the sys-tem stops immediately. “The LBR Med has a whole range of extremely fine sensors. It is quicker than stopping a human assistant,” says Prof. Hans-Florian Zeilhofer. “The robot then moves to a wait position and resumes the procedure from precisely this position as soon as it receives the all clear.” The system is rounded off with complex 3D planning, navigation and control software and hardware. It slots seamlessly into the operating room and works autonomously but provides the surgeon with full control of the proce-dure at all times.

Evaluation of the solution of the challenge

Until now, there was no solution for keeping the bone tissue in the area of the laser cut-ting surfaces intact and alive. CARLO now combines a laser and a robot for bone surgery in the form of the new “cold” laser technology with a small, lightweight, tactile robot designed for direct human-machine cooperation. Because its design was based on the sensitive, seven-axis LBR iiwa, the LBR Med already has sensitivity integrated into it. In the past, manufacturers had to develop this sensitivity for the robots they used for their products themselves, so they could be operated in the immediate vicinity of the patient. Efforts like these are now largely eliminated. “The LBR Med has installed force torque sensors in all seven axes, which makes it sensitive and safe. When there is even a little, unplanned contact, it remains still and interrupts its tasks. This sensitivity can also be used to operate the system intuitively and manually. Another advantage of the LBR Med is that the robot is already certified for integration into a medical product. It is the only robot component that has been certified according to CB Scheme process and can there-fore be easily incorporated into a medical product by medical technology companies. This has saved AOT AG a lot of time in the approval process.

Precision work through robot-guided laser ablation (© image AOT AG)

This is all still in the future, however, as far as the laser and robot for bone surgery are concerned, because certification as a medical product is still in progress. “Since CARLO is the first system of its kind, the supervisory authorities are understandably placing very high requirements on its safety,” explains Dr. Alfredo E. Bruno. AOT AG is already work-ing on the development of the second generation of CARLO with enhanced safety and performance features. These are tools that will place further demands on the LBR Med. For Prof. Hans-Florian Zeilhofer, CARLO represents the future of surgery because the software-guided robotic laser system for bone surgery supported by the LBR Med can perform highly precise cuts with any required pattern. “There are far more options open to the surgeon than with previous procedures.”