6450 nm wavelength tissue ablation using a nanosecond laser based on difference frequency mixing and stimulated Raman scattering.

A four-stage laser system was developed, emitting at a wavelength of 6450 nm with a 3-5 ns pulse duration, < or = 2 mJ pulse energy, and 1/2 Hz pulse repetition rate. The laser system successfully ablated rat brain tissue, where both the collateral damage and the ablation rate compare favorably with that previously observed with a Mark-III Free-Electron Laser.