COMPARISON OF TISSUE ABLATION USING TEA CO//2 AND Er:YAG LASERS.

Tissue ablation using two different IR-emitting lasers has been compared. The TEA CO//2 laser emits 1 J of 10. 6- mu m radiation in 2 mu s. The Er:YAG laser, which emits at 2. 94 mu m, was used in both a P-switched and normal spiking mode. The Q-switched laser delivers up to 100 mJ in a 150-ns long pulse (FWHM); operating normal mode, the laser emits up to 600 mJ in a 250- mu s-long envelope containing about twenty 1- mu s-long pulses. The emission of both lasers is strongly absorbed by water and thus tissue. Results for both lasers are described. It is found that a Q-switched Er:YAG laser can easily ablate tissue, creating incisions with as little as 5 mu m of residual thermal damage. Such incisions heal rapidly.