Novel contact lenses designed to slow progress of myopia: 12 month results

Abstract

Purpose : Correction strategies that reduce hyperopic defocus or impose myopic defocus can slow myopia progression. We assessed two novel contact lens (CL) designs for their efficacy to slow myopia progression. The first CL type imposed myopic defocus across both the central and peripheral retina; the second manipulated higher order aberrations to provide retinal image quality (RIQ) that degraded in the direction of myopic eye growth.

Methods : Myopic children (n=508 , ages 7 to 13 yrs (avg 10.4±1.3yrs) with cycloplegic spherical equivalents (SE) between -0.75 to -4.25D (avg -2.38 ±0.78D) were enrolled in a prospective, double-blind, clinical trial conducted in Guangzhou, China and randomised to one of 5 groups: a) control group wearing single-vision, silicone hydrogel (SH) CLs b) 2 groups wearing SH CLs with a central treatment zone of relative +ve power of +1.00D combined with relative +ve powers of +2.50D (CL I) and +1.50D in the periphery (CL II) and c) 2 groups wearing hydrogel CLs (see Fig1, test CLs III and IV). At baseline (BL) and 6 monthly intervals, measurements of cycloplegic (1% tropicamide) autorefraction and axial length (AL) were conducted on both eyes. Myopia progression between groups at 12 months was compared using linear mixed models and if significant (p<0.05), post hoc analyses with Bonferroni corrections were performed.

Results : At 12 months, 3 of the 4 test CL groups showed significantly reduced myopia progression compared to the control group for both SE and AL ( see Table); the CL II group showed reduced AL. Lens type, age, parental myopia and compliance were found to influence progression. Adjusted means for the reduction in myopia progression with the test CLs ranged from 21 to 29% for SE and 31 to 42% for AL, which increased to 27 to 33% and 38 to 56%, respectively, for those who were compliant (wore ≥6d/wk)

Conclusions : After 1 year, myopia progression was significantly reduced with novel CL. The results emphasise that imposing myopic defocus across both the central and peripheral retina or providing RIQ that degrades in the direction of eye growth can provide a signal to slow eye growth.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.

 

Figure 1

 

Table 1