Short-term visual performance through myopia control spectacle lenses with lenslets

Abstract

Purpose : To evaluate the impact on central distance visual acuity (VA) and contrast sensitivity (CS) in children of three different spectacle lens designs with lenslets used for myopia control while looking through the peripheral zones containing the lenslets.

Methods : Distance VA and CS were measured using Freiburg Visual Acuity and Contrast Test (FrACT) and CSV-1000 (Vector Vision Carp, USA), respectively. For each test, four spectacle lens designs were evaluated in random order: standard single vision lens (SVL) as a control, spectacle lens with concentric rings of highly aspherical lenslets (HAL), spectacle lens with concentric rings of slightly aspherical lenslets (SAL) and spectacle lens with honeycomb configuration of spherical lenslets (HC). To ensure vision through the lenslets zones, zones without lenslets were patched. 50 myopic children (mean age 12.7 ± 1.7 years, range 10 to 15 years, mean spherical equivalent refraction (SER) 3.22 ± 1.57 D, range -6.50 to -0.38 D) participated in the VA test; 36 myopic children (mean age 13.2 ± 1.2 years, range 10 to 16 years, mean SER 3.20 ± 1.67 D, range -7.25 to -0.75 D) participated in the CS test. All tests were done monocularly on the right eye with corrected-to-normal vision.

Results : Compared to SVL, VA through the lenslet zones of HAL, SAL and HC decreased significantly by 0.07 ± 0.09, 0.06 ± 0.09, 0.09 ± 0.07 LogMAR, respectively (all p<0.01). Decrease in VA was similar in HAL and SAL (p > 0.9) while significantly larger in HC compared to HAL (p = 0.02) and to SAL (p = 0.03). VA changes induced by lenslets showed no significant correlation with SER (all p > 0.05), but had a weak positive association with age for SAL (r = 0.36, p = 0.01) and HC (r = 0.31, p = 0.03), but not for HAL (p = 0.3). The lenslet structures did not affect CS at low spatial frequency (3 cycles per degree (cpd), p = 0.8). At mid to high spatial frequencies (6 to 18 cpd), CS was significantly reduced by HAL and HL (all p < 0.05), but not SAL (p > 0.05) compared to SVL. At high spatial frequencies (12 to 18 cpd) both SAL and HAL reduced CS significantly less than HC (all p < 0.01).

Conclusions : When looking through the lenslet structures, short-term visual performance was minimally reduced by spectacle lenses with lenslets compared to SVL. Concentric rings of aspherical lenslets had significantly lower impact on both VA and CS than honeycomb configuration of spherical lenslets.

This is a 2021 ARVO Annual Meeting abstract.