Pseudo-accommodative Cornea: A New Concept for Correction of Presbyopia

Abstract

Efficacy, predictability, stability, and safety of multifocal ablation with a peripheral near zone for correction of myopia, hyperopia, and presbyopia was assessed. We performed a retrospective study of 83 hyperopic eyes and 77 myopic eyes. Baseline mean spherical equivalent refraction in the hyperopia group was +1.54 +/- 0.90 D (range 0 to +4.00 D) and in the myopia group, -4.31 +/- 2.62 D (range -12.00 to -0.25 D). Mean near addition was 2.40 D in the hyperopia group and 1.75 D in the myopia group. All eyes had multifocal laser in situ keratomileusis (LASIK) with a peripheral near zone, using a Nidek EC-5000 excimer laser. Pseudoaccommodative cornea (PAC) software version 6T was used to calculate the multistep ablation profile. Three months after surgery, 80 eyes (96.4%) of the hyperopia group and 75 eyes (97.4%) of the myopia group were examined. Postoperative mean spherical equivalent refraction was -0.19 +/- 0.58 D (range -1.75 to +1.00 D) in the hyperopia group and -0.50 +/- 0.75 D (range -2.50 to -0.75 D) in the myopia group. Fifty-eight eyes (72.5%) of the hyperopia group and 50 eyes (66.7%) of the myopia group were within +/-0.50 D of emmetropia. One percent of eyes in the hyperopia group and no eyes in the myopia group lost 2 or more lines of BSCVA; 5% of eyes in the hyperopia group and 12% eyes in the myopia group gained 2 or more lines of BSCVA. Mean near addition was 0.11 D in the hyperopia group and 0.07 in the myopia group. Binocular unaided near visual acuity was J3 or better in all eyes of both groups and J1 or better in 35% eyes in the hyperopia group and 41% of eyes in the myopia group. Multistep multifocal ablation with a peripheral near zone using the Nidek EC-5000 excimer laser and PAC software version 6T was effective, predictable, stable, and relatively safe over a period of 3 months.