Application of real time iris recognition in LASIK for correction of moderate or high myopic astigmatism

Abstract

Objective To evaluate the application value of real time iris recognition in laser in situ keratomileusis (LASIK) for correction of moderate or high myopic astigmatism.Methods In this randomized controlled study,98 patients (181 eyes) with moderate or high myopic astigmatism were divided into two groups:the experimental group (49 cases,90 eyes) accepted real time iris recognize-guided LASIK,and the control group (49 cases,91 eyes) accepted conventional LASIK.The visual acuity,the best-corrected visual acuity,the degree and axis of astigmatism were compared between two groups at postoperative 1 month,3 months and 6 months.Results In the experimental group,static iris recognition detected that eye cyclotorsional misalignment was 2.83° ± 2.65°,dynamic iris recognition detected that the intraoperative cyclotorsional misalignment range was 0 ～ 6°.Six months after the operation,the naked vision of 86 eyes (95.6％) in the experimental group and 75 eyes (82.4％) in the control group surpassed the preoperative best-corrected visual acuity of each group (P ＜ 0.01 ).The degree of astigmatism in the experimental group (-0.29 ±0.23D) was significantly lower than that in the control group (-0.45 ±0.31D) (P ＜0.05).40 eyes (44.4％) in the experimental group and 26 eyes (28.6％) in the control group became non-astigmatism at 6 months after the operation.In the control group,oblique astigmatism increased significantly than that in the experimental group.Conclusion The real time iris recognition can compensate deviation from eye cyclotorsion,and it is a precise treatment for correction the degree and axis of astigmatism in LASIK. Key words: Iris recognition; Eye cyclotorsion; Astigmatism; Keratomileusis,laser in situ