Visual Performance of Two Daily Disposable Multifocal Contact Lenses in Presbyopic Soft Lens Wearers
Purpose: To measure high contrast visual acuity (HCVA) when presbyopic soft contact lens (CL) wearers, requiring a spectacle addition from +0.75 to +1.75 dioptres were fit bilaterally with delefilcon A daily disposable multifocal (DT1 MF) CLs and senofilcon A daily disposable multifocal (AOM MF) CLs. Methods: In this prospective, randomized, double-masked, cross-over, non-inferiority study, presbyopic CL wearers wore two types of multifocal CLs for 1 hour each. HCVA was measured monocularly and binocularly at 6m, 66cm and 40cm under photopic and mesopic conditions. Participants rated subjective visual clarity (0–100 scale, 100=very clear) after each HCVA assessment. Pupil size was assessed under photopic and mesopic conditions. Results: Twenty-eight participants (48.6 ± 5.3 years) completed the study. DT1 MF was non-inferior to AOM MF in HCVA at 6m, 66cm and 40cm in photopic and mesopic conditions for the dominant and non-dominant eye, and binocularly. There were no statistically significant differences between lenses for subjective visual clarity ratings for any of the viewing distances, whether evaluated for photopic or mesopic conditions for the dominant or non-dominant eye or binocularly. Mean pupil size in the dominant eye was 3.6 ± 0.5mm (2.6 to 4.5mm) and 5.1 ± 0.8mm (2.8 to 6.1mm) in photopic and mesopic conditions respectively. HCVA under photopic or mesopic illumination at 6m, 66cm or 40cm was not associated with pupil size (Pearson correlation, all p>0.05). Conclusion: Both lenses provided good vision across a variety of distances at high and low illumination. DT1 MF was non-inferior to AOM MF in HCVA under photopic and mesopic illumination at distance, intermediate and near. HCVA at all distances with both study lenses was independent of pupil size. Despite their different design, both study lenses performed equally well and provide a suitable vision correction for presbyopic CL wearers, irrespective of pupil size.