Higher Asphericity Yields Greater Myopia Control in Spectacle Lenses

Spectacle lenses with aspheric lenslets may reduce myopia progression and axial length elongation in children, with greater asphericity yielding better patient outcomes, according to a study published in JAMA Ophthalmology.

Researchers enrolled 157 children (mean age, 10.4±1.2 years, spherical equivalent refraction (SER) range -0.75 to -4.75 D) in a double-masked, parallel randomized study to determine whether lenses with higher asphericity had higher myopia control efficacy over a 2 year period. The team randomly assigned participants to 1 of 3 treatment groups: spectacle lenses with highly aspheric lenslets (HAL), spectacle lenses with slightly aspheric lenslets (SAL), and single vision lenses (SV). Primary outcome measures were changes in spherical equivalent (SE) and axial length from baseline to 2 year follow-up. 

Investigators noted a negative correlation between degree of asphericity and mean myopia progression with values of -0.66 D, -1.04 D, and -1.46 D for the HAL, SAL, and SV groups, respectively, at 2-year follow-up. Both HAL and SAL groups had less SER progression compared with the SV arm (0.80 D, 95% CI, 0.53-1.07 and 0.42 D, 95% CI, 0.15-0.70, respectively, P ≤.001 for both). SER progression for HAL was less than that of the SAL group (0.38 D, 95% CI, 0.11-0.64, P =.002).

Mean axial length increases from baseline to 2-year follow-up were 0.34, 0.51, and 0.69 in the HAL, SAL, and SV groups, respectively, with a significant difference noted in axial length increase among the treatment groups (P =.001).

“In children with myopia, wearing HAL significantly reduced the rate of myopia progression and eye growth over 2 years compared with SAL and SVL,” according to the researchers. “This study demonstrated a dose-dependent effect, with higher lenslet asphericity having greater myopia control efficacy.”

Study limitations include ethnic homogeneity among participants which limited the researcher’s ability to analyze study results on a global level, the inability to objectively determine lens wearing time, and a 3-week delay in follow-up resulting from COVID-19 shutdowns. 

Reference

Bao J, Huang Y, Li X, et al. Spectacle lenses with aspherical lenslets for myopia control vs single-vision spectacle lenses: a randomized clinical trial. JAMA Ophthalmol. Published online March 31, 2022. doi:10.1001/jamaophthalmol.2022.0401