Corneal sensitivity recovery after photorefractive keratectomy (PRK)

Abstract

Purpose: To establish the pattern of recovery of corneal sensitivity post-PRK using a non-invasive aesthesiometer. Methods: Two studies were undertaken. (1) A longitudinal study monitoring the recovery of corneal sensitivity in 10 patients over one year, following a PRK correction of −6D/6mm (correction (D)/ablation diameter (mm)). (2) A transverse study examining corneal sensitivity one year postoperative on 68 patients who underwent various correction procedures: −3D/5mm (n = 16), −3D/6mm (n = 13), −6D/5mm (n = 14), −6D/6mm (n = 12) and −6D/Multizone (n = 13). Results: (1) Corneal sensitivity showed an immediate drop at week 1 (P < 0.05), with a further decline at week 2 (P < 0.05). Sensitivity recovered slowly over the following months. (2) Corneal sensitivity was reduced in the PRK-treated eyes when compared to normal non-contact lens wearing eyes (P < 0.01). No specific procedures effect was found. Conclusions 1. The pattern of sensitivity change occurring is: (a) an initial rapid drop, followed by: (b) a slow recovery over 1 years. 2. At one year, sensitivity is still below both normal and contact lens wear levels. 3. The extent of sensitivity loss is not influenced by the depth of ablation.