【摘要】 分析近视准分子激光原位角膜磨镶术后，光学切削区偏中心情况，探讨偏中心的原因及预防措施，在近视准分子激光原位角膜磨镶术前及术后，采用计算机辅助角膜地形图分析系统对其中的１５５只眼进行检查，在术前后差异图上，测定光学切削区偏中心数值及方位。并分组进行比较。结果低、中度及高度近视组，术后光学切削区偏中心值分别为０．４５±０．２２ｍｍ及０．４５±０．２５ｍｍ；超高度及极高度近视组，术后光学切削区偏中心值则分别为０．６１±０．２７ｍｍ及０．８８±０．３７ｍｍ。偏中心方位各组间无明显差异，而且右眼与左眼一致，多数位于鼻上象限。结论超高度和极高度近视（屈光度＞－１０．００Ｄ）患者，准分子激光原位角膜磨镶术后光学切削区偏中心程度大于低、中度及高度近视组，其主要原因可能是由于术中角膜基质透明度下降，影响术者对位及患者注视指示灯光所致。更多还原

【Abstract】 To analyse the optical ablation zone decentration in patients who have undergone excimer laser in situ keratomileusis(LASIK)and try to find the reasons and prevention of the optical ablation zone decentration.Methods Optical ablation zone centration in 155 eyes before and after LASIK was tested using computer assisted videokeratography.On the differential maps,we messured amounts and directions of the optical ablation zone decentration.A comparison of decentration among those eyes was performed.Results The mean decentration of low,moderate and high myopia was 0 45±0 22mm and 0 45±0 25mm.The mean decentration of super high and extreme high myopia was 0 61±0 27 and 0 88±0 37mm.For the directions of the optical ablation zone decentration,there is no difference among the various degree myopic eyes.Most points of decentration are located in supranasal area.Conclusions Decentration amounts of super high and extreme high myopia(> 10 00D)are much lager than those of low,moderate and high myopia.The major reason for this may due to the decreasing of the corneal clarity during the surgery.更多还原