Purpose: To determine if photorefractive keratectomy with a 193 nm excimer laser could cause human corneal endothelial changes, mainly in high dioptric treatments.
Methods: 18 patients underwent a treatment ranging from 7 to 13 diopters at the corneal apex (mean 10.3 +/- 1.4 SD) with an estimated corneal thinning ranging from 62 to 116 microns (mean 90.7 +/- 12 SD). In these patients a comparison between the number and shape of the corneal endothelial cells has been performed before and 12 months after PRK.
Results: The mean cell density was 2818 +/- 337 mm2, before surgery, and 2894 +/- 301 mm2 after 12 months. The polymorphic index was 79.0 +/- 2.3, before surgery, and 81.0 +/- 5.0 after 12 months with no significant changes (p = 0.16 and P = 0.09, respectively).
Conclusions: These results show that photorefractive keratectomy does not cause any significant observable damage to the central corneal endothelium up to 12 months after surgery, even in high myopic treatments.