Ablation of human nail by pulsed lasers

Ultrashort pulse laser ossicular ablation and stapedotomy in cadaveric bone*†

“…1 and 2) reveal a circular channel through the long process of the incus measuring 400 microns in diameter. The higher magni®cation image in Figure 2 demonstrate little evidence of explosive damage from expanding gases due to vaporization of the tissue matrix commonly seen in ablation craters created using Holmium [8,18,21] or erbium [8,18] lasers. For comparison, see images published by Neev [8], Jovanovic [8], and Wong [21].…”

“…The ablation rate is lower than those produced by erbium (20±30 mm/pulse), holmium (<0.5 and > 2 mm/pulse), and excimer (2±7 mm/ pulse) lasers [18], but the ef®ciency of hard tissue removal per unit of energy delivered is greater than with these lasers. For comparison, the ablation rate for Er:YAG was 20 mm/pulse at a¯uence of 10 J/cm 2 , and the ablation ef®ciency was approximately 0.5 mm/mJ in human nail tissue.…”

“…The ablation rate of just over 1 mm/pulse observed in this study is comparable to those measured in other hard tissues irradiated, using this USPL [18,19]. The ablation rate is lower than those produced by erbium (20±30 mm/pulse), holmium (<0.5 and > 2 mm/pulse), and excimer (2±7 mm/ pulse) lasers [18], but the ef®ciency of hard tissue removal per unit of energy delivered is greater than with these lasers.…”

“…When tissue is exposed to high-intensity short pulse duration (< 10 picoseconds (ps)) laser irradiation, multiphoton absorption occurs, resulting in plasma mediated tissue ablation con®ned to a very small tissue volume [18,19]. When plasma is formed free electrons dominate the light absorption process, which is very weakly dependent on wavelength.…”

Surgical applications of femtosecond lasers

“…Targets on the teeth are accessible because they are superficial, but the transparency of the eye permits access to its internal targets. While preliminary research is carried out in fields such as dermatology (both skin [46] and fingernail [47]) and otology (inner and middle ear [48]), this research has not yet generated a critical mass of interest, perhaps because other simpler laser systems or treatment methods exist.…”