Abstract:  Objective To compare the effectiveness and safety between epipolis laser in keratomileusis (Epi-LASIK) and laser epithelial keratomileusis(LASEK) for treatment of high myopia patients. Design Prospective comparative cases series. Participants Group A including 50 cases (100 eyes) was underwent Epi-LASIK and group B including 50 cases (100 eyes) underwent LASEK. Method Before surgery and at 1, 3, 5, 7 days after surgery corneal epithelial healing was observed, and at 1, 3, 6 months after surgery subjective and objective visual quality changes were observed. Main Outcome Measures UCVA, BSCVA, safety index (SI), effective index (EI) and Haze grade. Results  There were 87 cases finishing 6-month follow-up, including group A of 43 patients (86 eyes) and group B of 44 patients (88 eyes). The unhealed area in group B was （18.21± 1.16） mm2 larger than group A (18.21±1.16 mm2) (P=0.04) at 3 days after the operation and epithelium was healed 5 days after the operation. At 6 months postoperatively, the average UCVA between group A and group B were 1.02±0.03 and 0.94±0.03 (P=0.184). Average BSCVA between group A and group B were 1.02±0.03 and 1.20±0.02 (P=0.496). The BSCVA down two lines or more of group A was in 2 eyes (2.33%) at 6 months after surgery, and of group B in 0 eye. At 6 months, the SI of group A was 1.02±0.02 and group B was 1.01±0.01 (P=0.768). The EI of group A was 1.39±0.28 and group B 0.97±0.03 (P=0.079). There were 10 eyes (11.63%)  in group A and 6 eyes (6.82%) in group B with high intraocular pressure after two weeks. At 6 months, Haze grading of two groups was 0.02±0.02 and 0.10±0.05 (P=0.177). At 6 months, the residual diopter within ±0.5 D was 84.88% in group A and 88.64% in group B, respectively (P=0.465). At 18c/d spatial frequency of contrast sensitivity function (CSF) under mesopic condition in group B was better than in group A (P=0.020). There were no significant differences between two groups at the other spatial frequencies. Conclusion Generally, Epi-LASIK and LASEK for treatment of high myopia patients was safe and effective. The visual quality was no significant difference between Epi-LASIK and LASEK. Epi-LASIK can make corneal epithelial healing faster. (Ophthalmol CHN, 2014, 23: 51-56)
 

Key words: Epi-LASIK, LASEK, high myopia