【摘要】 目的:评价PRK切削中心偏离瞳孔中心的数值、方向及其动态变化规律。方法:采用EyeSys角膜地形图仪对210眼PRK术前及术后10天、1个月及3个月的角膜地形图进行分析。结果:PRK术后10天、1个月及3个月的平均偏心值分别为O.57±0.26mm、O.69±0.29mm、0.76±0.37mm(P<0.05),但切削偏心的方向基本不变,左右眼总的偏心向量均指向鼻下侧。结论:几乎所有术眼均可发生切削中心的偏离,偏心趋向于鼻下方。术后三个月内,偏心值有逐渐增大趋势。术后10天的角膜地形图是反映PRK手术激光切削后角膜表面形态的有力证据,而术后1个月,3个月的创面轮廓则是准分子光束的切削和基质创面反应性增殖共同作用的结果。更多还原

【Abstract】 The value, direction and its dynamic regular rule of ablation decentration from pupil center in phot-orefractive keratectomy (PRK) were evaluated by means of corneal topography. Methods- An investigation was carried on 210 eyes examinated by Eyesys topography before the operation and 10 days. 1 month and 3 months postoperatively respectively. Results: Mean ablation decentration was 0.57±0.26mm, 0.69 ±0.29mm and0.76± 0.37mm(P<0.05) in above three periods respectively, whereas its direction didn’t change obviously.The general decentration vector was located inferior to the nose. Conclusion. Decentration from pupil center occurred almostly in all the eyes.and the tendency of decentration directed downward. It is revealed that the topographic map at 10 days after the operation can describe accurately the anterior surface of corneal, otherwise, the topographic map 1 month and 3 month after the operation is a compound which has been ablated by excimer laser and hyperliferated by active inflammation.更多还原