Abstract
Purpose :
To assess two 2nd generation extended depth-of-focus (EDOF) prototype contact lenses (CLs) for visual performance and binocular vision function against a single-vision contact lens (SVCL) in young adults.
Methods :
In a prospective, double-masked, crossover, dispensing clinical trial, 35 myopes (aged 18-35 years) wore two new prototype EDOF CLs (EDOF1, EDOF2) and a SVCL (1-Day Acuvue Moist) each for a week. CLs were fit based on distance refraction and worn on a daily-disposable basis for a minimum of 6 hours/day.
After a week of wear, the following measurements were obtained: high-, low-contrast visual acuities (HCVA, LCVA) at 6m, 70cm and 40cm, stereopsis at 40cm, horizontal phorias at 3m and 33cm, and monocular accommodative facility at 33cm. Accommodative response at 40cm was measured with the Shin-Nippon autorefractor using a consensual response method.
Subjective performance was assessed on a 1-10 numeric rating scale for vision clarity, ghosting, driving vision, haloes, ease of focussing, vision stability, vision satisfaction and ocular comfort. Participants also rated the frequency of eyestrain symptoms. Linear mixed models and chi-square tests were used for analysis and the level of significance was set at 5%.
Results :
SVCL provided significantly better HCVA than EDOF2 at 6m (mean difference [MD]=2 letters, p<0.001) and better LCVA at 6m than EDOF1 (MD=2 letters, p=0.041) and EDOF2 (MD=7 letters, p<0.001). No significant differences between EDOF CLs and SVCL were found for stereopsis, distance and near phoria or accommodative facility (p≥0.215). Accommodative lag was significantly reduced with SVCL compared to EDOF CLs, i.e. more accommodative effort with SVCL (SVCL: 0.74±0.32D, EDOF1: 0.96±0.42D, EDOF2: 1.00±0.44D, p≤0.032).
Subjectively, SVCL was only rated significantly better than EDOF1 for vision clarity at distance (MD=0.4 units, p=0.017). SVCL was rated significantly better than EDOF2 for vision clarity at all distances (MD=0.5-0.8 units, p≤0.005), driving vision (MD=0.8 units, p<0.001), and vision satisfaction (MD=0.8 units, p=0.019). No significant differences between EDOF CLs and SVCL were found for ghosting, haloes, ease of focussing, vision stability, ocular comfort or frequency of eyestrain.
Conclusions :
Similar to previous findings, 2nd generation EDOF CLs caused minimal disruption to the binocular system while reducing accommodative effort in young adults.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.