Evaluation of dry eye syndrome after LASIK and surface ablation: a comparative study

Aim of the study The aim of the present study was to evaluate the severity of dry eye following laser in-situ keratomileusis (LASIK) and surface ablation (photorefractive keratectomy). Patients and methods This study was designed as a prospective, nonrandomized, comparative clinical study. In total, 40 eyes of 20 patients were divided into two equal groups (group A and B). In group A, 20 eyes underwent LASIK with mechanical microkeratome flap. In group B, 20 eyes underwent surface ablation with mechanical or laser epithelial removal. Dry eye was evaluated by tear breakup time (TBUT) and Schirmer test preoperatively, and then 1 week, 1 month, and 3 months postoperatively. Results Preoperative mean TBUT in LASIK patients was 13 ± 1.87 s and mean TBUT in surface ablation patients was 12.9 ± 1.79 s (P = 0.435). At 1 week postoperative, the mean TBUT in LASIK patients was 7.6 ± 1.93 s (P < 0.05) and in surface ablation patients it was 8.58 ± 1.79 s (P < 0.05). At 1 month postoperative, the mean TBUT in LASIK patients was 8.95 ± 2.06 s (P < 0.05) and in surface ablation patients it was 10.25 ± 1.58 s (range = 7-13 s) (P < 0.05). At 3 months postoperative, the mean TBUT in LASIK patients was 10.1 ± 1.89 s (P < 0.05) and in surface ablation patients it was 11.2 ± 1.72 s (P < 0.05). Preoperative mean Schirmer test score in LASIK patients was 15.25 ± 2.61 mm and mean Schirmer test score in surface ablation patients was 15.2 ± 2.84 mm (P = 0.475). At 1 week postoperative, the mean Schirmer test score in LASIK patients was 9.35 ± 2.37 mm (P < 0.05) and the mean Schirmer test score in surface ablation patients was 10.2 ± 2.09 mm (P < 0.05). At 1 month postoperative, the mean Schirmer test score in LASIK patients was 10.8 ± 2.23 mm (P