准分子激光上皮瓣下角膜磨镶术后角膜地形图分析

Analysis of corneal topography after exciter laser epithelial keratomileusis

目的分析准分子激光上皮瓣下角膜磨镶术(Laser epithelial keratomileusis,LASEK)后角膜地形图的动态变化。方法对188例(365眼)LASEK手术患者进行术后1、3、6个月的视力、屈光度及角膜地形图检查。结果术后1个月切削形态中平滑型占61.6%,半环型、钥匙孔型、肾型和哑铃型占30.5%,中心岛型占6.0%。中心岛型对术后最佳矫正视力影响较大。切削形态随时间延长逐渐变规则。术后切削区中心偏离瞳孔中心的距离为(0.57±0.31)mm(0-1.85mm),偏心方向以鼻侧居多。术后1-3个月角膜屈折力变化较大,高度近视比低度近视回退明显。结论LASEK手术后角膜切削形态较规则平整,但仍存在偏心切削的问题。角膜地形图为分析评估LASEK手术的效果提供了客观依据。

Objective To analyze the changes of corneal topography after excimer laser epithelial keratomileusis （LASEK）. Methods Corneal topographies of 188 patients （365 eyes） were performed before surgery and a month, 3 months and 6 months after LASEK. Results According to the topography, the percent of uniform ablations was 61.6%, semicircular, keyhole, kidney and dumbbell shaped ablations were 30.5% and central island one was 6.0% one month after LASEK. The central island pattern was associated with a greater tendency toward loss of best corrected, visual acuity in early post operative period. All types tended to change toward regular patterns. The mean decent ration from the papillary center to ablating center was （0.57 ± 0.31）mm （range from 0 - 1.85mm）. In beth eyes, a preponderance had decent rations to the nasal（especially in the left eyes）. High myopia began regression at 1 - 3 months after LASEK. Conclusion There were much more regular ablation shapes after LASEK. But it still has the problem of decent ration ablation. Corneal topography provides a subjective method to evaluate the result of LASEK.