Myopia Control Efficacy of Spectacle Lenses with Dual-Index Aspherical Lenslets: A 1-Year Randomized Clinical Trial

Abstract

Objective: To examine the myopia control efficacy, in terms of axial elongation, of a new myopia control spectacle lenses with Dual-Index Aspherical Lenslets (DIAL) embedded within the lens, compared with single-vision spectacle lenses (SVLs) over a 1-year period.

Design: A prospective, randomized, double-masked clinical trial.

Participants: Eighty children aged 8 to 13 years with myopia (spherical equivalent refraction [SER] between -0.75 and -4.75 diopters [D]) were recruited.

Intervention: Participants were randomized to either the DIAL or SVL spectacle lenses group (1:1 ratio).

Main outcome measures: Axial length (AL), noncycloplegic subjective refraction, and best-corrected visual acuity (BCVA) were measured at baseline and 6-month intervals. Questionnaires on adaptation and compliance were administered during all visits.

Results: A total of 76 (N = 38 in each group) participants (mean [standard deviation] age, 10.8 [1.6] years) completed the 1-year visit. Mean (± standard error) 1-year AL change in the DIAL and SVL groups was 0.04 ± 0.02 and 0.22 ± 0.04 mm, respectively. A mean difference of -0.18 mm (95% confidence interval [CI], -0.26 to -0.10 mm; P < 0.001) was found. Mean 1-year SER change in the DIAL and SVL groups was -0.13 ± 0.06 and -0.39 ± 0.08 D, respectively, with a mean difference of 0.26 D (95% CI, 0.06-0.46 D; P = 0.01). Compared with SVL, younger children (8 to <11 years) and older children (11-13 years) in the DIAL group had significantly less axial elongation (-0.29 mm less for younger children and -0.09 mm less for older children), with greater myopia control effect of DIAL spectacle lenses among the younger group than among the older group (P = 0.004 for interaction). No significant differences between the lens groups were found for distance BCVA (P = 0.36). All participants adapted within 3 to 4 days regardless of lens group. No significant differences in mean daily wearing time were seen between the DIAL and SVL groups (P = 0.53).

Conclusions: Dual-Index Aspherical Lenslets spectacle lenses showed good myopia control efficacy, in terms of axial elongation, compared with SVL, among children aged 8 to 13 years in Singapore.

Financial disclosures: Proprietary or commercial disclosures may be found in the Footnotes and Disclosures at the end of this article.

Keywords: Aspherical lenslets; Myopia control spectacle lenses; Optical intervention; Randomized trial.

Figure 1

Illustration of spectacle lenses with Dual-Index Aspherical Lenslets (DIAL). On the left: frontal view of the entire lens. In the middle: cross-section incorporating elements of the array of contiguous lenslets organized in a hexagonal mesh. On the right: 3-dimensional view of the cross-section. The array of contiguous aspherical lenslets is formed at the interface of the 2 materials (polycarbonate and polymethyl methacrylate).

Figure 2

Consolidated Standards of Reporting Trials (CONSORT) flowchart. DIAL = Dual-Index Aspherical Lenslets; SVL = single-vision spectacle lenses.

Figure 3

A, Change in unadjusted AL. B, Change in SER by subjective refraction. C, Change in SER by noncycloplegic autorefraction. Spectacle lenses with DIAL are represented in green with triangular markers, while SVL are represented in red with round markers. Error bars represent standard errors of the mean. AL = axial length; D = diopters; DIAL = Dual-Index Aspherical Lenslets; SER = spherical equivalent refraction; SVL = single-vision spectacle lenses.

Figure 4

Spectacle lenses with DIAL are represented in green with triangular markers, whereas SVL are represented in red with round markers. Error bars represent standard errors of the mean. DIAL = Dual-Index Aspherical Lenslets; SVL = single-vision spectacle lenses.