Abstract

Objective: to evaluate the severity of Dry eye(mild, moderate or severe) following laser in-situ Keratomileusis and surface ablation (photorefractive keratectomy/PRK)

Methods: Nonrandomized, prospective and comparative clinical study. A total of 40 eyes of 20 patients were divided into two groups (group X and Y). In Group X, 20 eyes were operated with Femtosecond assisted LASIK and in group Y, 20 eyes underwent surface ablation with laser epithelial removal. Dry eye was evaluated by Tear breakup time (TBUT) and Schirmer 2 tests. All patients were followed up at 1 week, 1 month, and 3 months postoperatively.

Results: Mean TBUT Preoperatively in LASIK patients was 14.551.81s and mean TBUT in surface ablation was 14.391.92s (p=0.291). Mean TBUT at 1week, 1 month, and 3 months in LASIK patients was 7.55 , 8.85 and 9.89seconds respectively. Whereas, Mean TBUT in surface ablation patients at 1week, 1 month and 3months was 8.99, 10.88 and 10.89seconds resp. P value was less than 0.05 between these 6 readings. Preoperative mean Schirmer values in LASIK patients was 15.19 and surface ablation patients was 15.54(p= 0.345). Mean Schirmer’s values of LASIK group at 1week, 1 month and 3 months were 10.23, 10.78 and 13.73mm respectively (p<0.05). Mean Schirmer’s in surface ablation patients was 10.82, 11.86 and 15.35mm respectively (p<0.05).

Conclusion: LASIK and surface ablation both cause Dry eye but its higher in LASIK patients.

Keywords: LASIK, photorefractive keratectomy, surface ablation, tear breakup time, Schirmer test.