UC Irvine

BACKGROUND: Laser light is known to stimulate nerves. This study investigated alternative wavelengths for nerve stimulation. MATERIALS AND METHODS: The sciatic nerves of rats were irradiated with four different lasers-a Ho:YAG (2100 nm), a Yb:glass fiber laser (1495 nm) and diode lasers (1450 nm and 1540 nm). RESULTS: All lasers evoked a visible leg twitch response, and electromyography confirmed muscle activation. The Yb:glass laser at 1495 nm delivered through a single mode fiber was found to be the most effective stimulus. The stimulation threshold for a 2 millisecond pulse from the Yb:glass laser was determined to be 3.7+/-2.8 mJ/cm(2). CONCLUSIONS: The Yb:glass laser has the potential for use in neurostimulation, as an alternative to electrical stimulation.