光学生物测量仪角膜曲率指导下白内障超声乳化透明角膜切口矫正原有散光的疗效分析

Analysis of corneal astigmatism changes after clear corneal incision along the steep axis guided by IOL-master

目的探讨在光学生物测量仪(IOL-master)引导下,取最陡曲率子午线透明角膜切口行白内障超声乳化术,评价其矫正白内障患者原有角膜散光的疗效。方法挑选71例(85眼)术前IOL-master检查角膜曲率差值(△K)为1.5～3.5 D的老年性白内障患者。按散光轴向分组:顺规散光组(A组)23眼,散光轴位>45°且≤135°;逆规散光组(B组)29眼,散光轴位≤30°或>150°;斜轴散光组(C组)11眼,散光轴位>30°且≤45°或>135°且≤150°;对照组(D组)22眼。A、B和C组的主切口均位于最陡曲率子午线的透明角膜上;D组的主切口均位于角膜缘11点方位。术者坐位可根据切口所在轴位灵活改变,但无需改变常规操作习惯。观察术后1周、1个月、3个月的视力及角膜散光度。结果所有患者手术均顺利,且均无术后并发症发生。术后3个月裸眼视力≥1.0,A组7眼(30.4%)、B组12眼(41.3%)、C组2眼(18.2%)、D组3眼(13.6%),A、B组显著高于C、D组(P值均<0.05),而A组与B组及C组与D组间的差异均无统计学意义(P值均>0.05)。术后3个月,A、B组的△K分别为(1.39±0.49)、(1.37±0.57)D,均显著低于术前的(1.87±0.41)、(1.96±0.53)D(P值均<0.05),且均显著低于D组的(1.75±0.64)D(P值均<0.05)。结论在IOL-master测量的最陡角膜曲率上取透明角膜切口行白内障超声乳化术较常规上方切口可有效矫正部分角膜散光,且该方法适宜在大规模常规白内障手术中开展。对顺规及逆规散光的矫正效果较好;对斜轴散光的矫正效果不可预知,可能导致过矫。

Objective To evaluate the corneal astigmatism changes after cataract phacoemulsification on clear corneal incision along the steep axis measured by IOL-master. Methods Eight-five eyes of 71 senile cataract patients with the corneal curvature （AK） ranged from 1.5 to 3.5 D were divided into 4 groups： group A （23 eyes with the rule, WTR.. 45°axis ≤ 135°）; group B （29 eyes against the rule, ATR.. axis ≤30°=or 〉150 °）; group C （11 eyes, oblique axis, OBL： 30 °〈axis≤45° or 135 °〈axis≤150°）; and group D （control, 22 eyes）. Clear corneal incision was along the steepest axis in groups A, B and C, only routine superior incision placed on 1 1 clock in group D. Operator can move the seat according to the axis but need not to change operational habit. The visual acuity and corneal astigmatism changes were recorded one week, one month and three months postoperatively. Results The operations were successfully performed in all patients and no postoperative complications occurred. The naked vision achieved 1.0 in 7 eyes in group A （30.4%）, 12 eyes in group B （41.3%）, 2 eyes in group C （18.2%） and3 eyes in group D （13.6%）. Compared with groupsC andD, the results in groups A and B were significantly different （all P〈0. 05）. But there was no significant difference in groups C and D （P〉0. 05） or in groups A and B （P〉0.05）. The average corneal astigmatism in group A and group B were significantly lower than the preoperative ones （[ 1.39±0.49] D vs. [ 1.87 ± 0.41] D, [ 1.37 ± 0.57] D vs. [1.96 ±0.53] D, all P〈0. 05） 3 months postoperatively, and also lower than that in group D （[1.75 ± 0.64] D, all P〈0. 05）. Conclusion Cataract phacoemulsification after clear corneal incision along the steep axis guided by IOL-master is more effective than conventional incision, and this method can be spread in routine cataract surgery on large scale. Correction effects on astigmatism with the rule and against the rule are satisfactory, but it is unpredictable on oblique astigmatism and likely to lead to an overcorrection.