Chronic dry eye and regression after laser in situ keratomileusis for myopia

PURPOSE: To examine the relationship between chronic dry eye and refractive regression after laser in situ keratomileusis (LASIK) for myopia. SETTING: Excimer Laser Vision Centre and Centre for Eye Research, Queensland University of Technology, Brisbane, Australia. METHODS: This study was based on a retrospective analysis of a clinical database and a case study series. Data (N = 565 eyes) were collected before and after (2 weeks and 1, 3, 6, and 12 months) LASIK. Three case studies, which highlight appropriate management strategies for LASIK candidates with dry eye, are presented. RESULTS: Regression after LASIK was related to chronic dry eye. It occurred in 12 (27%) of 45 patients with chronic dry eye and in 34 (7%) of 520 patients without (P<.0001). Patients with chronic dry eye had significantly worse myopic outcomes than those without (1 month, P =.02; 3 months, P =.01; 6 months, P =.004; 12 months, P =.008). The risk for chronic dry eye was significantly associated with female sex, higher attempted refractive correction, greater ablation depth, and the following pre-LASIK variables: increased ocular surface staining; lower tear volume, tear stability, and corneal sensation; and dry-eye symptoms before LASIK. The risk for regression was significantly associated with higher attempted refractive correction, greater ablation depth, and dry-eye symptoms after LASIK. Case studies demonstrated that intensive dry-eye treatment may improve the refractive outcome and alleviate the need for enhancement surgery. CONCLUSION: The risk for refractive regression after LASIK was increased in patients with chronic dry eye.