01.11.2024

In spinal canal stenosis, bony growths narrow the spinal canal, which often leads to chronic pain or paralysis in patients. Around 111,000 of these operations are performed in Germany every year, with surgery often being the only solution.

The proximity to the spinal cord makes the treatment risky, as there is often a high risk of damage to the nerve structures when milling the constrictions. To reduce these risks, the Fraunhofer Institute for Laser Technology ILT has developed a laser procedure that is supported by optical monitoring and robotics and enables precise incisions to be made.

Image: Surgical staff standing next to a person on a stretcher in the operating room, with a robot-assisted system to the right; Copyright: Fraunhofer ILT, Aachen / Ralf Baumgarten

Surgically opening the vertebral body is highly risky due to the spinal cord lying in the spinal canal. The robotically assisted laser surgery system developed at the Fraunhofer ILT is intended to replace mechanical high-speed milling

Products and exhibitors related to this topic

Exhibitors and products related to this topic can be found in the database of MEDICA:

Laser technology as an alternative to high-speed milling

short-pulse laser that removes bone tissue in a precise and thermally gentle manner. This laser works in nanosecond pulses that enable minimally invasive cuts to be made with pinpoint accuracy without causing thermal damage to the surrounding tissue. Dr. Achim Lenenbach, head of the Laser Medical Technology and Biophotonics department at Fraunhofer ILT, explains: "Thanks to the optical monitoring and precise control of the laser cutting process, our procedure could prevent serious injuries to the spinal cord and nerve roots in future."

Optical coherence tomography (OCT) for reliable cut monitoring

To monitor the cutting process in real time, the laser procedure combines the cutting laser with optical coherence tomography (OCT). This system makes it possible to record the remaining bone thickness at the cutting line in three dimensions. Once the specified residual thickness has been reached, the cutting process is automatically stopped. OCT technology is the key to safe and controlled cutting, which prevents the laser from accidentally reaching deeper layers or areas close to nerves.

Another safety aspect of the procedure is the use of a spray mist system, which keeps the bone moist during the treatment and thus further reduces the thermal stress on the surrounding tissue.

Robotic support and haptic feedback for precise handling

The use of a collaborative robot (cobot) to guide the laser applicator provides the surgeon with haptic feedback, which is missing during the cutting process of the milling machine. The robot's sensors detect the force exerted on the surgeon's arm and translate this into feedback so that the laser applicator can always be handled in a controlled and precise manner. This haptic feedback is supplemented by OCT monitoring to ensure that the handpiece is only advanced when the specified residual thickness is reached.

Visual feedback and surgical planning software for optimized precision

For additional guidance, the system is equipped with surgical planning software and a navigation system so that the incisions made with the laser can be visualized in real time. The ability to visually track the progress of the incision provides surgeons with a precise overview of the proximity to sensitive structures and thus contributes to the increased safety of the procedure.

MEDICA-tradefair.com; Source: Fraunhofer Institute for Laser Technology ILT

More about the Fraunhofer ILT at: www.ilt.fraunhofer.de/en