Comparison of the Corneal Thickness before and after Photorefractive Keratecomy

Objective: To investigate the change of corneal thickness after photorefractive keratectomy (PRK) and the relationship between the corneal thickness and Haze. Methods: The corneal thickness was measured before and 1,3,6,12 and 24 months after PRK with an DGHA biometer; the grades of Haze after PRK were examined with a slit lamp biomicroscope.Results: The corneal thicknesses before and 1,2,6,12 and 24 months after operation showed very significant difference ( p 0.001). There were also significant difference between the corneal thicknesses 1 month after the operation and 3,6,12 and 24 months after the operation ( p 0.05) , but it had no significant difference among 3,6,12 and 24 months after operation ( p 0.05) . The Haze of all cases were under grade 1 . Conclusions: The corneal thickness became stable 3 months after PRK. PRK is safe when myopia is less than 6.00D and the cutting depth is less than 80um.