New research presented at the 2023 Association for Research in Vision and Ophthalmology (ARVO) meeting featured 4-year data on the effects of highly-aspherical lenslets (HAL) spectacles for mitigating pediatric myopia.
To note: the Essilor Stellest lenses by Essilor Ltd. are based on the optical design of HAL lenses.
This follows previously-reported 3-year outcomes released earlier this year.
Let’s start with background data on these HAL spectacles.
Spectacle lenses with aspherical lenslets are designed to generate myopia control signals prior to the retina.
Previous data from a 2-year trial of 157 myopic pediatric patients (ages 8 to 13) found that spectacle lenses with HAL and with slightly aspherical lenslets (SAL) were effective in slowing both myopia progression by 0.80 D vs. 0.42 D and axial length (AL) elongation by 0.35 mm vs 0.18 mm, respectively.
Got it. So how does that tie into the 3-year data?
Investigators sought to build on the initial 2-year data to determine three key items:
- If an additional year of HAL spectacle wear still maintained myopia control efficacy.
- If myopic pediatric patients still had myopia control efficacy after switching from originally wearing SAL or single-vision spectacle lenses (SVL) to HAL lenses for 1 year.
- The long-term myopia efficacy of wearing HAL lenses over 3 years.
Now tell me about the study.
Following the original 2-year, double-blind, randomized study, 89% (151) patients continued in the extended third-year, non-blind trial: those who wore HAL lenses continued to do so for the additional year (HAL1 group; n = 54); patients who originally wore SAL (HAL2 group; n = 53) or SVL (HAL3 group; n = 50) switched to wearing HAL.
Additionally, a new control group (nSVL group; n =56) was added to assess myopia progression in the third year and was combined with the original SVL group to determine myopia control efficacy for all 3 years.
What was being assessed?
The study primarily tracked spherical equivalent refraction (SER) and axial length (AL) every 6 months during the third year.
Third-year findings?
The mean myopia progression in the nSVL group was -0.56 (0.05) D versus the HAL1 group (-0.38 [0.05] D, p = 0.02); HAL2 group (-0.36[0.06] D, p = 0.01); and HAL3 group (-0.33 [0.06] D, p =0.005).
The mean AL elongation in the nSVL group was 0.28 (0.02) mm versus the HAL1 group (0.17 [0.02] mm, p<0.001; HAL2 group (0.18 [0.02] mm, p<0.001); and HAL3 group (0.14 [0.02] mm, p<0.001).
Meaning…?
The myopia progression and axial elongation in all three HAL groups (all p > 0.05) were comparable in the third year.
And what about the 4-year data?
Patients wearing the HAL lenses saved over 1.25 D of myopia after 4 years in the trial, with myopia progression and axial eye elongation tracking slower when compared to the control, single-vision lens group.
Further, the myopia progression and axial elongation were also observed in patients ages 11 to 16 years of age.
Take away.
When taking into account myopia progression and axial length elongation, the latest data supports sustainability of the HAL lenses for myopia control over 4 years.