Researchers have confirmed that spectacle lenses with highly aspherical lenslets could slow myopia progression and axial elongation in children, according to a new five-year follow-up study. Fewer children developed high myopia after five years compared with an extrapolated control group of single-vision spectacle lenses.
In the two-year trial before the follow-up, “the use of highly aspherical lenslets (HAL) [was] shown to slow myopia progression and axial length (AL) elongation by 0.80 D and 0.35 mm, respectively,” lead study authors Xue Li and Yingying Huang wrote in Eye and Vision.
Children from the HAL group of the two-year randomized clinical trial (n = 43, mean age = 10.7 years) completed five years of follow-up.
In the follow-up study, myopia progression was evaluated through annual cycloplegic spherical equivalent refraction (SER) and AL measurements. A control group was created using extrapolated data from the initial single-vision lens (ESVL) group. Myopia progression and AL elongation over the additional three years were projected using established annual reduction rates (9.7% for SER and 15% for AL).
Myopia progression in the HAL group was −1.27 ± 0.14 D over 5 years vs −3.03 ± 0.18 D in the ESVL group. The difference in progression was −1.75 ± 0.24 D (P < .001). Much fewer participants progressed in myopia of more than 2.50 D in the HAL group (5%) compared with a projected 64% in ESVL (P < .001). Similarly, fewer participants developed myopia of −6.00 D or worse in the HAL group (9%) vs 38% in ESVL (P =.002).
Axial elongation in the HAL group was 0.67 ± 0.06 mm vs 1.40 mm in the ESVL group, with a difference of 0.72 ± 0.10 mm less in the HAL group (P < .001). A greater proportion of participants (12%) experienced less than 0.2 mm of axial elongation in the HAL group compared with 2% of participants in the ESVL group, and fewer participants (28%) in the HAL group had AL greater than 26 mm compared with a projected 54% in ESVL (P = .011).
Multivariate analysis showed that younger baseline age and earlier myopia onset were significantly associated with faster progression and AL elongation. Adjusted mean changes were:
SER: HAL = −1.38 ± 0.15 D vs ESVL = −2.94 ± 0.14 D (difference = 1.56 D, P < .001)
AL: HAL = 0.73 ± 0.06 mm vs ESVL = 1.35 ± 0.05 mm (difference = 0.62 ± 0.08 mm, P < .001)
No adverse events (such as blur, dizziness, or headache) were reported. Although wear time was not tracked in the last 2 years, participants had consistently increased wear time across the first 3 years, which indicated habitual long-term use.
“This outcome is comparable to the results of [the] LAMP Study that estimated 0.05% atropine slowed myopia progression by 1.67 D and axial elongation by 0.75 mm, also using an ESVL group,” the authors wrote. They further described other trials that found similar results, such as a long-term study of dual-focus soft contact lenses for six years and orthokeratology lenses.
Seven children discontinued the study during years 4 to 5, but there were no statistically significant differences in baseline age, SER, AL, and myopia progression or AL elongation between them and the children who completed the study. “Their differences in myopia progression and axial elongation were less than 0.20 D and 0.07 mm per year, respectively,” the authors noted.
The children in the HAL group will continue to be monitored for another two years, but “HAL spectacles effectively reduced the rate of myopia progression and eye growth,” the authors concluded.
This article was originally published on conexiant.com.
