Visual performance of single-vision contact lenses utilizing opaque, nonrefractive features for potential myopia...

Contact lenses (CLs) utilizing opaque, nonrefractive features may purposefully modulate retinal ganglion cell activity away from the baseline activity. This is a nonrefractive mechanism that may reduce myopia progression. However, the visual performance of CLs with opaque features is unknown.

This study aimed to compare the visual performance and binocular/accommodative function of CLs with opaque features (test) against MiSight (control-1) and single-vision (control-2) CLs.

This was a prospective, randomized, unmasked, cross-over study where 35 myopic CL wearers (18 to 39 years) wore each design for at least 5 days. Visual performance was subjectively assessed using 1 to 10 numeric ratings comprising clarity of vision, lack of ghosting, vision when driving, overall vision satisfaction, and willingness to purchase (yes/no: based on vision and myopia efficacy). Visual acuity measurements comprised monocular and binocular high and low contrast visual acuity at 6 m, and binocular high contrast visual acuity at 70 and 40 cm. Binocular function was assessed using heterophorias at 3 m and 40 cm. Accommodative function was assessed using monocular accommodative facility (MAF) at 40 cm and dynamic monocular accommodative response (AR: 6 m, 70 cm, and 40 cm).

Test was rated higher than control-1 (p<0.001) and control-2 was rated higher than test (p≤0.0052) for all subjective ratings. More participants were willing to purchase test compared with control-1 for vision and myopia efficacy (p<0.001), while there was no difference between test and control-2 for either question (p>0.7). Both controls were better than test for all acuity-based measurements (p≤0.0013). MAF at 40 cm was better with test compared with control-1 (p=0.010) and not different to control-2 (p>0.99). AR was higher with test than both controls at 70 cm (p<0.0001), higher than control-1 at 40 cm (p<0.0001), and not different to control-2 at 40 cm (p=0.12). There were no differences between CLs for AR at 6 m or heterophorias at 3 m or 40 cm (p>0.1).

Compared with control-1, the test offered better visual performance, a higher proportion of participants willing to purchase, and better MAF. Compared with control-2, the test offered worse visual performance, but the proportion of participants willing to purchase was not different, and accommodative function was comparable.