Electroretinographic evaluation of single vision contact lenses with non-refractive opaque features.

CLINICAL RELEVANCE: Electroretinography provides insights into how optical interventions, e.g., contact lenses (CLs), may influence retinal function. Understanding acute retinal responses is important for the ongoing development of myopia control strategies.

BACKGROUND

To investigate the acute effects of single-vision (test) soft CLs incorporating non-refractive opaque elements on retinal function. These lenses are designed to modulate retinal ganglion cell activity through Active Reconfiguration in Retinal Encoding of Spatio-Temporal signalling with a potential for myopia control.

METHODS

In a randomised, contralateral-eye study, 30 participants (18 to 25 years; refractive error: 0.00D to -5.50D) wore single-vision test and control CLs. Electroretinograms were recorded at baseline, 10, and 40 minutes using red flash stimuli (38 Troland-seconds at 3.8 Hz) on a blue background (380 Trolands). Time-amplitude and Discrete Wavelet Transform analyses quantified changes in retinal response. Metrics included a-wave and b-wave peak times and amplitudes, Photopic Negative Response (PhNR) amplitude and timing, P-ratio, W-ratio, and OFF/ON pathway coefficients.

RESULTS

TTest lenses induced significant delays in a-wave (mean difference [MD]: 0.26 ms, p = 0.008) and b-wave (MD: 0.26 ms, p < 0.001) peak times, with no significant amplitude changes. PhNR amplitude was significantly reduced (MD: 0.42 µV, p = 0.01), and peak time was delayed (MD: 0.51 ms, p = 0.02). P ratio (MD: -0.04, p = 0.001), and W-ratio (MD: -0.04, p = 0.004) significantly suppressed with test lenses. Time-frequency analysis revealed selective suppression of OFF-pathway activity (40Hz coefficient, MD: -0.89 µV-s, p = 0.02) with test lenses, while ON-pathway components remained stable. 80Hz oscillatory potentials were significantly reduced with test lenses (MD: -1.35 µV-s, p = 0.02).   .

CONCLUSION

Non-refractive opaque features within an otherwise single-vision CL can induce short-term changes in retinal signalling, characterised by temporal shifts in post-receptoral signalling, potentially suggesting pathway-specific modulation of inner retinal circuits. Additional studies are needed to confirm the preliminary findings to facilitate insights into the retinal mechanism of action with such interventions.