Visual outcomes, contrast sensitivity and defocus profile with an aspheric monofocal intraocular lens utilizing positive spherical aberration.

Abstract

Purpose: To evaluate visual outcomes following bilateral implantation of the RayOne EMV intraocular lens with targeted micro-monovision.

Setting: Southend Private Hospital, UK.

Design: Retrospective cohort.

Methods: 50 subjects (100 eyes) assessed at 12 to 18 months post-operatively. Emmetropia was targeted in the dominant eye and myopia of -0.50 to -1.00D in the non-dominant eye. Uncorrected and distance corrected visual acuity was assessed monocularly and binocularly at distance (6m), intermediate (70cm) and near (40cm). Defocus was assessed from +1.50D to -4.00D monocularly and binocularly. Contrast sensitivity was assessed using a computerised Pelli-Robson chart.

Results: Mean Spherical Equivalent (MSE) was -0.05±0.34D and -0.91±0.60D in the dominant and non-dominant eyes respectively. Uncorrected distance visual acuity (UDVA) was significantly different in the dominant (0.08±0.10LogMAR) and non-dominant eye (0.29±0.17LogMAR). (p<0.01). Corrected distance visual acuity (CDVA), distance corrected intermediate visual acuity (DCIVA) and distance corrected near visual acuity (DCNVA) were similar between eyes. However, significant differences were found between binocular uncorrected intermediate visual acuity (UIVA) (0.16±0.11LogMAR) and DCIVA (0.31±0.11LogMAR) (p <0.01) also, binocular uncorrected near visual acuity (UNVA)(0.30±0.17LogMAR) and DCNVA (0.50±0.19 LogMAR) (p<0.01). The non-dominant eye shows superior acuity eye in both UIVA (p<0.01) and UNVA(p<0.01). Contrast sensitivity showed no significant difference between eyes (p = 0.06). Significant improvement binocularly compared to monocularly was seen through imposed defocus -0.50 to -2.50D.

Conclusion: The RayOne EMV with micro-monovision is a reliable method for improving intermediate and near visual acuity, by increasing the range of focus without compromise of distance acuity or contrast sensitivity.