LASIK术后角膜曲率、前房深度及眼轴长度的改变

Changes of corneal curvature,anterior chamber depth and ocular axis length after LASIK

目的探讨准分子激光角膜原位磨镶术对患者的角膜曲率、前房深度及眼轴长度产生的影响。方法准分子激光角膜原位磨镶术患者61例122眼,用光学相干生物测量仪(IOL-Master)分别测量术前及术后0.5 a的角膜曲率、前房深度及眼轴长度,用电脑自动验光仪分别测量术前及术后0.5 a的角膜曲率,对结果进行统计学分析比较手术前后各个参数的改变,用临床病史法计算出术后矫正角膜曲率(K矫正),建立K矫正对术后测量的角膜曲率(K术后)的回归公式,并比较IOL-Master和电脑自动验光仪测量术前和术后角膜曲率的一致性。结果 IOL-Master测量术前和术后的角膜曲率分别为(43.25±1.15)D和(39.13±1.92)D,前房深度分别为(3.65±0.21)mm和(3.55±0.20)mm,眼轴长度分别为(25.58±0.89)mm和(25.49±0.87)mm,手术前后三组数据相比差异均有统计学意义(均为P=0.000)。电脑自动验光仪测量的手术前后角膜曲率分别为(43.20±1.15)D和(39.06±1.89)D,推导的回归公式为:K矫正=1.093×K术后-4.013。Bland-Altman分析显示IOL-Master和电脑自动验光仪在测量术前和术后角膜曲率上一致性较好。结论准分子激光角膜原位磨镶术后患者的角膜曲率、前房深度及眼轴长度均较术前降低,相比较角膜曲率改变更明显,可采用回归公式对术后角膜曲率进行矫正。IOL-Master和电脑自动验光仪在测量术前和术后角膜曲率上一致性较好,临床上可以替代使用。

Objective To investigate the effects of laser in situ keratomileusis（ LASIK） on the corneal curvature,anterior chamber depth and ocular axis. Methods Sixty-one LASIK patients（ 122 eyes） were collected. C orneal curvature,anterior chamber depth and axial length of the eyes were measured by IO L-Master before and 6 months after operation. C orneal curvature of the eyes were measured by auto-refractometer before and 6 months after operation. The results were statistically analyzed and compared the changes in each parameter before and after the operation. The postoperative corrected corneal curvature（ Kcorrected） was calculated by the clinical history method,the regression formula of Kcorrected with postoperative corneal curvature（ Kpostoperative） was established,and the consistency of the corneal curvature measured by IOLMaster and auto-refractometer before and after the operation was compared. Results Preoperative and postoperative corneal curvature measured by IO L-Master were（ 43. 25 ± 1. 15） D and（ 39. 13± 1. 92） D,anterior chamber depth were（ 3. 65 ± 0. 21） mm and（ 3. 55 ± 0. 20） mm,ocular axial length were（ 25. 58 ± 0. 89） mm and（ 25. 49 ± 0. 87） mm,respectively,the differences were statistically significant（ all P = 0. 000）. Preoperative and postoperative corneal curvature measured by auto-refractometer were（ 43. 20 ± 1. 15） D and（ 39. 06 ± 1. 89） D. The regression formula was deduced as follow s： Kco rrected= 1. 093 × Kpo sto perative- 4. 013. Bland-Altman analysis show ed that IO L-Master and auto-refractometer were good consistent in the measurement of preoperative and postoperative corneal curvature. Conclusion The corneal curvature,anterior chamber depth and axial length are decreased in patients after LASIK,especially corneal curvature. The regression formula can be used to correct the corneal curvature after operation. IO L-Master and auto-refractometer were consistent in the measurement of preoperative and postoperative corneal curvature,and it can be used instead clinically.