Myopia progressed slower in the highly aspherical lenslet spectacle subset compared to single vision spectacles during the first 2 stages of the study.
New research shows highly aspherical lenslet spectacles (HAL)is effective at slowing the progression of myopia.
A team, led by Padmaja Sankaridurg, Brien Holden Vision Institute (BHVI), evaluated and compared myopia progression with highly aspherical lenslet spectacles with conventional, single vision spectacles.
Some estimates have myopia affecting more than half of the global population by 2050, which would come with a substantial societal burden.
For example, the estimated potential lost productivity cost because of myopia was $250 billion in 2015.
“It has been demonstrated that any level of myopia is at risk of complications; however, eyes with highmyopia have the greatest risk of complications and related vision impairment,” the authors wrote. “Eyes with higher levels of myopia also have an earlier onset of complications affecting their productivity. These data indicate the need to reduce progression of a myopic eye to reduce the burden.”
In the prospective, double-blind, single-center, randomized, cross-over trial, the investigators examined 119 pediatric patients aged 7-13 years in Vietnam. The patient population had a spherical equivalent refractive error of -0.75 to -4.75D.
Each participant was randomized to wear either highly aspherical lenslet spectacles or conventional single vision spectacles. The participants then crossed over to the other option for an additional 6 months after the first 6 months.
The investigators sought main outcomes of the comparison of the 2 spectacles for Δ in spherical equivalent refractive error and axial length (AL) during each stage, as well as the comparison of ΔSE/AL with SV betweenthe 2 groups to determine if myopia rebounded when switched from HAL to SV (HSH group).
Group 1 was designated as HSH (HAL-SV-HAL), while group 2 was labeled SHH (SV-HAL-HAL).
The results show myopia progressed slower in the highly aspherical lenslet spectacle subset compared to single vision spectacles during the first 2 stages (SEΔ stage 1: -0.21 vs -0.27D, P = 0.317, stage 2: -0.05 vs -0.32D, P <0.001; ALΔ stage 1: 0.07 vs 0.14 mm, P = 0.004; stage 2: 0.04 vs 0.17 mm, P <0.001).
However, ΔSE/AL with SV was not different between the HSH andSHH groups (ΔSE, -0.33±0.27D vs -0.27±0.42D, P = 0.208; ΔAL, 0.17±0.13 mm vs 0.13±0.15 mm, P = 0.092).
Participants in both groups reported wearing the lenses for an average of 14 hours a day.
“In this cross-over trial, intergroup and intragroup comparisons indicate that HAL slows myopia,” the authors wrote. “Children were compliant with lens wear and data was not suggestive of rebound when switched from HAL to SV.”
The study, “Spectacle lenses with highly aspherical lenslets for slowing myopia: A randomized, double-blind, cross-over clinical trial,” was published online in the American Journal of Ophthalmology.