Abstract
Purpose :
Multifocal soft contact lenses (MFCLs) are prescribed to inhibit myopia progression; these include aspheric and concentric power designs. We investigated the effect of different MFCL designs on visual quality, vergence and accommodation in young-adult myopes.
Methods :
Participants were 26 adults aged 19 to 25 years (21 females, 5 males) with myopia (SER: range −0.50 to −5.75D, average −2.6±1.7D), normal binocular vision and no history of past myopia control. Pupil sizes were 4.4±0.9 mm during distance viewing and 3.7±0.8 mm at near. In a random sequence, at one visit, each wore 4 different contact lenses: Proclear single vision distance, MiSight concentric dual-focus (+2.00D), distance centered aspheric (CV aspheric, +2.50D) (all CooperVision), NaturalVue aspheric (Visioneering Technologies, +8 to +11D at pupil margin, up to +20D at optic zone edge). Comprehensive visual quality and binocular function assessments were made with each.
Results :
The four lenses differed in distance (ANOVA, p=0.001) and near visual acuity (p=0.011), and in contrast sensitivity (Pelli-Robson, p=0.001). Compared to the single vision lens, the CV aspheric had the greatest visual impact: 0.19±0.14 logMAR distance acuity reduction, 0.22±0.15 log contrast sensitivity reduction. Near acuity was affected less than distance acuity and was worst for the NaturalVue (0.05±0.07 logMAR near acuity reduction). Exophoric shifts were greater with aspheric lenses (Howell card near phoria, 33cm, paired t-test, 1.8±2.4Δ, CV aspheric, p<0.001, NaturalVue, p=0.001; 1.7±1.7Δ), and were smaller with the concentric MiSight (0.5±1.3Δ, p=0.046). The aspheric lenses reduced measured accommodation responses (Grand Seiko Autorefractor, 33cm, p=0.001): the CV aspheric decreased the response by 0.6±0.5D and the NaturalVue by 0.5±0.6D. However, the MiSight did not alter the measured accommodation (p=0.275). Negative relative accommodation reduced with the aspheric lenses (ANOVA, p=0.001): by 0.9±0.5D with the CV aspheric and 0.5±0.7D with the NaturalVue.
Conclusions :
MFCLs alter visual performance, vergence and measured accommodation responses; the aspheric lenses had greater effect than the concentric lens.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.