Tissue effects of Ho:YAG laser with varying fluences and pulse widths

摘要

We investigated the effect of varying fluence and pulse width on the ablation rate and consequent thermal damage of the Ho:YAG (2.130 $mu@m) laser. The rate of ablation on fresh bovine knee joint tissues, fibrous cartilage, hyaline cartilage, and bone in saline was determined after varying the fluence (160 - 640 J/cm$+2$/) and pulse width (150, 250, 450 $mu@sec, FWHM) at a repetition rate of 2 Hz. A 400/440 $mu@m fiber was used. The ablation rate increased linearly with the fluence. In fibrocartilage, different pulse durations generated significant changes in the ablation rates, but showed minor effects on hyaline cartilage and bone. The heat of ablation for all three tissue types decreased after lengthening the pulse.