Corneal light transmission and roughness after refractive surgery.

PURPOSE

To determine the relation between the corneal light transmission measurements and the epithelial surface properties in hen corneas after different refractive surgery techniques photorefractive keratectomy, laser in situ keratomileusis, and laser-assisted subepithelial keratomileusis, and a group with only epithelial corneal removal (deepithelialization).

METHODS

Five groups of hen corneas with different treatments and a control group were analyzed at 30 days. Direct transmittance and corneal light scattering were measured by a scatterometer developed by our group. Quantitative and systematic measurements of external and internal roughness and epithelium thickness were assessed using standard techniques developed for quantitative analysis of microphotographs of the corneal epithelium.

RESULTS

Data analysis revealed that the roughness in the epithelial surface was associated with the corneal light transmission. The direct transmittance of light showed a significant correlation with the epithelial roughness in the control (r = -0.99, p < 0.05) and photorefractive keratectomy (r = -0.99, p < 0.05) groups. However, there was no relation between the epithelial thickness and the corneal light transmission measurements.

CONCLUSIONS

The experimental results suggested that the roughness of the epithelial surfaces is related to the light transmission in the cornea.