Effects produced by different types of laser in córnea of Guinea pigs: Identification of a laser capable of producing superficial lesions without leaving scars.

SUAREZ AC; SUAREZ MF; CRIM N; MONTI R; URRETS ZAVALIA JA; SERRA HM

Archivos de la Sociedad Española de Oftalmología

Elsevier

Año: 2015 vol. 90

0365-6691

Purpose: To evaluate the effects of four different types of lasers withdifferent power and exposure time conditions in the cornea of normal guinea pigs. To determine whichlaser and conditions only damage the epithelium and superficial stroma and to study the kinetics ofwound healing.Methods: Damage was induced in the cornea of guinea pigs using different powers andexposure times of 4 types of Laser: Argon, CO2, Diode and ND-Yag and such injuries were evaluated bybiomicroscopy (BM) and optical microscopy. Corneas from other normal animals were exposed toArgon laser (350 mW, 0.3 seconds, 50 μm of diameter) and the induced alterations were studied atdifferent times using BM, Optical Coherence Tomography (OCT) and Transmission ElectronMicroscopy (TEM).Results: Only Argon laser at 350 mW, 0.3 seconds, 50 μm of diameter producedepithelium and superficial stroma lesions. Some leukomas were observed by BM, and they disappeared by day 15. Corneal thickness measured by OCT decreased in the eyes treated with Argon laser, duringthe first week. By TEM, different ultra structural alterations in corneal epithelium and stroma wereobserved during the early days, which disappeared by day 15.Conclusions: It was possible to developreproducibly corneal epithelium and anterior stroma injuries using Argon laser at 350 mW, 0.3seconds, 50 μm of diameter. In vivo and in vitro studies showed that injured corneas with these laserconditions did not leave irreversible microscopic or ultrastructural alterations.