The effect of spectacle-induced low myopia in the non-dominant eye on the binocular defocus curve with a non-diffractive extended vision intraocular lens

Abstract

Purpose: To quantify the changes in the binocular defocus curve associated with the Vivity™ non-diffractive extended vision intraocular lens when the dominant eye was targeted for emmetropia and the non-dominant eye was artificially targeted for slight myopia using spectacles. Patients and Methods: This was a non-interventional research study of the corrected binocular defocus curve associated with binocular emmetropia (Setting A) and with emme-tropia in the dominant eye and two different levels of myopia simulated in the non-dominant eye (−0.50 D, Setting B and −1.00 D, Setting C). Subjects were patients implanted with the AcrySof® IQ Vivity® intraocular lens in both eyes 3 to 12 months previously. Using the defocus data, the percentage of subjects with a continuous 2.5 D range of vision (distance to 40 cm) was calculated for various levels of minimum visual acuity (VA). Results: Forty subjects were enrolled. The mean spherical equivalent refraction was −0.06 D ± 0.36 D, with 0.37 D ± 0.29 D of refractive cylinder. There was no statistically significant difference in the mean VA at −0.25 D or at −0.50 D vergences between the test Settings, but there was a statistically significant difference at all other vergences. Differences were particularly noticeable at −2.00 D, −2.50 D and −3.00 D, where higher myopia in the non-dominant eye yielded better binocular VA. A 2.5 D range of functional vision (20/25) was achieved by 38% of subjects at Setting A, 68% of subjects at Setting B and 85% of subjects at Setting C. At setting C, all but one subject (39/40, 97.5%) had a 2.5 D range of vision with a VA of 20/32 or better. Conclusion: Significant gains in binocular near vision, with only a nominal effect on distance vision, can be achieved with the Vivity IOL by leaving the non-dominant eye of patients with 0.50 D or 1.00 D of myopia.