Comparison of the effect of SBK and Epi-LASIK on correcting high myopia

Objective To evaluate the efficacy of sub-Bowman keratomileusis (SBK) and epipolis laser in situ keratomileusis (Epi-LASIK) for correcting high myopia. Methods Ninety-one patients (182 eyes) underwent SBK or Epi-LASIK surgery for correcting high myopia,including 53 patients (106 eyes) for SBK and 38 patients (76 eyes) for Epi-LASIK.Visual acuity,remained diopter and corneal haze were examined after operation.The results were analyzed statistically. Results Patients had different degree of uncomfortable feeling early time after Epi-LASIK.Both groups showed no keratectasia by corneal topography examination 6 months after operation.One week postoperatively,the proportion of visual acuity ≥0.8 for SBK (77.4％) was more than that for Epi-LASIK (46.1％) (P ＜ 0.05).No significant differences were found in that of SBK (92.5％,95.3％,94.3％)and that of Epi-LASIK (85.5％,94.7％,90.8％) one-month,three-months and six-months postoperatively (P ＞ 0.05).The recovery of visual acuity after SBK was quicker than Epi-LASIK.There was no statistic meaning of remained diopter between SBK [(-0.24±0.42)D,(-0.38±0.51)D,(-0.40±0.46)D]and Epi-LASIK [(-0.32±0.40)D,(-0.44±0.60)D,(-0.52±0.55)D] 1 month,3 months and 6 months postoperatively (P ＞ 0.05).Both groups showed no refractive regression after operation.Haze was not found in SBK group.0.5 degree of haze was found in 2 eyes after Epi-LASIK 3 months postoperatively,and was disappeared 6 months postoperatively. Conclusions SBK and Epi-LASIK are both safe and effective for correcting high myopia.SBK is superior to Epi-LASIK in respect of visual acuity recovery at early time. Key words: High myopia; Sub-Bowman keratomileusis; Epipolis laser in situ keratomileusis