Abstract
Purpose:
To correlate subjective visual performance responses with through-focus retinal image quality (RIQ) metrics obtained on presbyopic participants fitted with single vision (SV) and multifocal (MF) contact lenses.
Methods:
Thirteen presbyopic participants (50.2 ± 3.5 years, SE: +1.38 to -5.50D) who needed adds of +1.00 or +1.25D were fitted bilaterally with AirOptix Aqua™ SV and AirOptix Aqua™ MF lenses [Alcon, USA]. Using the EyeMapper, a global aberrometer, on-axis ocular wavefront aberration profiles with lenses were captured. Five independent repeats were performed under natural pupils. Additionally, participants pupil sizes were measured at different illumination conditions (scotopic (0 Lux), mesopic (80 Lux) and photopic (300 Lux)) using a custom-built instrument. Post-processing routines in Matlab using the 6th order Zernike polynomial (z1 to z28) obtained from the EyeMapper yielded through-focus retinal image quality metrics (visual Strehl Ratio in the Fourier domain) over natural and mesopic pupil sizes. The participants’ subjective visual performance responses were obtained at far, intermediate and near reading visual distances, separately for each eye when fitted with both SV and MF lenses.
Results:
Out of twenty-six eyes, approximately 70% of the RIQ plots calculated each over natural and mesopic pupil size correlated with the subjective visual performance response at far, intermediate and near visual distances, for both SV and MF lenses. The shape of the RIQ for most of the SV lenses produced a high peak at far visual distance while MF lens produced gradual increase at far visual distance and plateaued through intermediate and near reading visual distances.
Conclusions:
Through-focus retinal image quality metrics can be used as a robust indicator to assess the visual performance for presbyopic participants. The interpretation should however be carefully aligned with the objective performance measures like visual acuity and contrast sensitivity.