Postoperative Effect of LASIK Surgery on Macular Region in Myopia

OBJECTIVE To investigate the postoperative effect of LASIK surgery on macular region in myopia. METHODS We studied 46 eyes of 23 patients with best-corrected vision ≥1.0 who underwent LASIK for myopia. Myopic patients were divided into two groups which were medium and low myopia group and high myopia group according to pre-operative spherical equivalent (SE). Optical Coherence Tomog-raphy (OCT) examination was performed in macular region of 46 myopic eyes before LASIK,and 1 day,3 days,1 week,1month after LASIK. The retinal thickness of macular region with 6mm diameter centered on the macular fovea was measured and the results were showed in 9 areas of retinal map in OCT. The refraction and best-corrected visual acuity (BCVA) of 46 myopic eyes were recorded simultaneously on above-mentioned study stages. RESULTS The best-corrected vision of high myopia group was ≥1.0 on above-mentioned postoperative study stages. There was statistical significance in the retinal thickness of macular central fovea in M1 area of high myopia group between before LASIK and on postoperative 1 day and 3 days (P0.05 on 1 day; P0.01 on 3 days). The increasing retinal thickness of macular central fovea in M1 area of high myopia group has positive correlation with preoperative refractive diopters and laser treatment time. There was no statistical significance in the retinal thickness of macular central fovea of medium and low myopia group on postoperative 1 day and 3 days. There was no statistical significance in the retinal thickness of M2～M9 areas in 46 myopic eyes between before LASIK and on postoperative 1 week and postoperative 1 month(P0.05). CONCLUSIONS Mild macular central fovea edema after LASIK was found within mostly in high myopia and this is correlated with high refractive diopters and long laser treatment time. But this mild macular edema was reversible and had no association with loss of BCVA. Thevacuum aspiration and application of excimer laser in LASIK surgery were positively safe for myopia.