Evaluation of iris recognition system for wavefront-guided laser in situ keratomileusis for myopic astigmatism

Purpose

To evaluate the visual and refractive outcomes of wavefront-guided laser in situ keratomileusis (LASIK) using an iris recognition system for the correction of myopic astigmatism.

Setting

Centre for Eye Research Australia, Melbourne Excimer Laser Research Group, and Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia.

Methods

A comparative analysis of wavefront-guided LASIK was performed with an iris recognition system (iris recognition group) and without iris recognition (control group). The main parameters were uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity, amount of residual cylinder, manifest spherical equivalent (SE), and the index of success using the Alpins method of astigmatism analysis 1 and 3 months postoperatively. A P value less than 0.05 was considered statistically significant.

Results

Preoperatively, the mean SE was −4.32 diopters (D) ± 1.59 (SD) in the iris recognition group (100 eyes) and −4.55 ± 1.87 D in the control group (98 eyes) (P = .84). At 3 months, the mean SE was −0.05 ± 0.21 D and −0.20 ± 0.40 D, respectively (P = .001), and an SE within ±0.50 D of emmetropia was achieved in 92.0% and 85.7% of eyes, respectively (P = .07). At 3 months, the UCVA was 20/20 or better in 90.0% and 76.5% of eyes, respectively. A statistically significant difference in the amount of astigmatic correction was seen between the 2 groups (P = .00 and P = .01 at 1 and 3 months, respectively). The index of success was 98.0% in the iris recognition group and 81.6% in the control group (P = .03).

Conclusion

Iris recognition software may achieve better visual and refractive outcomes in wavefront-guided LASIK for myopic astigmatism.