Evaluating the efficacy of Nd:YAG fourth harmonic (266 nm) in comparison with ArF excimer (193 nm) in laser corneal reshaping: ex vivo pilot study.

Purpose: Laser corneal reshaping is a common eye surgery utilized to overcome many vision disorders. Different UV laser wavelengths can be effective in the treatment. However, the ArF excimer laser (193 nm) is the most commonly used due to its high absorption in the cornea.

Assessing the local temperature of human cornea exposed to surface ablation by different laser refractive-surgery devices: a numerical comparative study.

To evaluate the local temperature at corneal tissue after applying single laser pulse from six commercial devices; Medilex™, Katana laser-soft, MEL90, Technolas-Teneo317, Alcon EX500, and PulzarZ1. The temperature distribution is simulated using finite element solution of the Penne's bio-heat transfer equation on a 3-D model of human cornea using the manufacturer's assigning parameters. The obtained results showed that the heating effect of Katana laser soft is 40% lower than MEL90 and Pulzar™ Z1, while the broad beam Medilex™ showed the minimum temperature rise especially at 248-nm laser radiation.

Dependence of the heating effect on tissue absorption coefficient during corneal reshaping using different UV lasers: A numerical study.

Corneal reshaping using laser ablation effect is a well-known ophthalmologic operation implemented to correct many vision disorders. UV pulsed lasers are utilized in this surgery due to their high absorption in corneal tissue without affecting the other parts of the eye. Ideally ablation may not be associated with heat transport, since high temperature is the enemy of soft tissues.