After the 3-year MiSight 1 day clinical trial, the control group children were switched to MiSight. A ‘virtual control group’ mathematical model, previously published, was utilized to demonstrate a continued myopia control effect across six years, plus effectiveness of treatment for children who commenced wear at age 11-15 years.
This study measured central and relative peripheral refraction (RPR) in children aged 6-7 years and 12-13 years at baseline and again one year later. There was no correlation found between central and peripheral refraction in the younger group. In the older group, more hyperopic temporal RPR was correlated with a myopic shift, but only explained 10% of the variance in refraction after 12 months.
It’s known that emmetropizing children undergo axial eye growth of around 0.1mm per year. Is this amount of growth in myopes also ‘physiologic’? In this study, data from six myopia control clinical trials was analyzed to find the axial growth component which did not result in a change in refraction. For myopes, this ‘physiologic’ growth appears to be less than 0.1mm per year, which has implications for judging progression and treatment success.
A country-wide intervention to increase outdoor time in 5-6 year olds resulted in the prevalence of myopia decreasing from 15% in the 2014 cohort (before the intervention) to 8% in 2016 cohort (exposed to the intervention for up to two years) and was stable for three years thereafter. Increasing outdoor time works!
This study utilized data from over 15,000 participants aged 35-74 years and found a five-year cumulative incidence (new onset) of myopic maculopathy in the general population of 3 in 1,000. In 509 eyes with over 6D of myopia, 7% had myopic maculopathy and of these 50% worsened over the study period.
This study reported that children wearing DIMS spectacle lenses showed increased sub-foveal choroidal thickness than controls at 1 week which increased in the first 6 months and was maintained at 2 years. There was a correlation between more choroidal thickening and less axial elongation, but choroidal thickening only explained around 8% of the variation in axial length.
The BLINK study found that +2.50 Add centre-distance multifocal contact lenses (MFCLs) slowed myopia progression but the +1.50 Add didn’t. Further analysis indicates that increased peripheral defocus created by the +2.50 Add only accounted for around 15% of the myopia control effect, indicating other mechanisms are involved.
A combination of higher baseline myopia, parental myopia and faster 3-year progression in earlier childhood were strongly predictive of teenage high myopia in this study. Young patients with these combination of factors should receive closer clinical monitoring and timely interventions to slow myopia progression.
This research showed that the concentration of atropine which reaches the retina is 400 times less than by topical administration; and that higher concentrations directly exposed to the mouse retina influence retinal signaling. Whether this is indicates a possible mechanism or unintended impact of atropine, and how this may translate to atropine use in humans, is unknown.
When looking through the ‘treatment zones’ of three different types of myopia controlling spectacle lenses with lenslets, visual acuity is reduced by 3-5 letters and mid-to-high frequency contrast sensitivity is mildly affected compared to single vision spectacles. We’re yet to learn if small differences between designs may influence patient preference.