Retinal response to two commercially available contact lenses for myopia control

Abstract

Aims/Purpose: Myopia control contact lenses (CLs) have shown optimistic results in eye growth retention in children. However, it is still unknown the retinal mechanisms of defocus detection. This study evaluated the electrophysiological response of the retina with two myopia control CLs, compared to single‐vision CLs.Methods: High‐contrast visual acuity (VA) and the retinal activity of 16 eyes (16 subjects, 27.5 ± 5.7 years, 12 female) with myopia (from −0.75 to −6.00 D, astigmatism >1.00 D) were assessed with two single‐vision CLs (Omafilcon A – SVo – and Filcon 5B – SVf) and two myopia control CLs (dual‐focus – DF, Omafilcon A – and extended‐depth‐of‐focus – EDOF, Filcon 5B). The global‐flash multifocal electroretinogram (gf‐mfERG) was recorded with the Reti‐port/scan21 (Roland Consult) with a 61‐hexagons stimulus in physiological pupil conditions. The implicit time (milliseconds) and response density (nV/deg2) of the direct (DC) and induced (IC) components were compared between CLs of matching material.Results: All CLs showed similar VA (p > 0.050). The implicit times did not show statistically significant differences. DF showed higher response density of both DC and IC components at all retinal areas, with a statistically significant difference in the parafoveal DC component (difference of 2.77 [6.23–1.44] nV/deg2, p = 0.038), compared with the SVo. EDOF showed a higher response density of about 13.31 [23.88–3.85] nV/deg2 (p = 0.032) in the foveal IC component, compared with the SVf. The remaining retinal areas did not show statistically significant differences.Conclusions: The retina seems to respond differently to distinct CL's optical designs. The two myopia control CLs increased the electrophysiological response of the retina, but with different effects, without affecting the implicit time of the response. Multifocal contact lenses with peripheral defocus induce different foveal and parafoveal activities that might be involved in the mechanism of myopia control.