Optical nerve stimulation and bone drilling

Bone ablation experiment: The laser beam is focused through the irrigation system onto the bone surface. A thermal camera is used for feedback on the ablation depth via detection of the point of maximum temperature (red triangle) on one of the faces perpendicular to the drilling face.
Bone ablation experiment: The laser beam is focused through the irrigation system onto the bone surface. A thermal camera is used for feedback on the ablation depth via detection of the point of maximum temperature (red triangle) on one of the faces perpendicular to the drilling face.

Optical nerve stimulation and bone drilling are two applications that have been studied in different areas. In these applications water is the most important component. Near Infrared and infrared wavelengths have high absorption in water.

It has been observed that laser assisted bone cutting causes less damage to the tissue than mechanical drilling. We therefore investigate and optimize the use of high power infrared laser ablation for bone cutting or drilling.

In optical nerve stimulation, infrared laser light is used to stimulate peripheral nerves to generate an action potential. Optical nerve stimulation gives better spatial selectivity and has less stimulation artifacts than electrical stimulation. The technique is still new and we investigate the influence of different laser parameters on stimulation efficiency in Lumbricina.

One of our research goals is the combination of these techniques in minimally invasive cochlear implantation surgery. In this procedure drilling and stimulation could be integrated in a single optical system, where the stimulation serves as feedback to safeguard the nerves.