Researchers: Myopia management may become standard of care
Evidence-based research on the safety and efficacy of different treatments aided practitioners in managing myopia in children, according to a review published in Ophthalmic and Physiological Optics.
“There may soon exist a continuum of care for myopia starting with delay of onset and followed by optical and pharmaceutical interventions to slow progression,” Kathryn Richdale, OD, PhD, of the University of Houston College of Optometry, and colleagues wrote. “It may be that spectacle prescriptions for myopic children incorporate a design that has been shown to slow progression, and traditional single vision lenses will no longer be recommended.”
Leung and colleagues released a report in 1999 indicating that progressive addition spectacle lenses (PALs) slowed myopia by 0.50 D. The COMET study, a randomized clinical trial by Gwiazda and colleagues, found a reduction in myopia progression of 0.20 D among children wearing PALs compared to children wearing single-vision lenses.
A second COMET clinical trial of children with myopia with high accommodative lag and near esophoria was conducted. Investigators again randomly assigned patients to receive either +2.00 D PALs or single-vision lenses. Results showed that the mean 3-year progression was –0.87 D in the PAL group and –1.15 D in the single-vision group. Both COMET studies were shown to be statistically significant, but not clinically relevant.
Lam and colleagues randomly assigned 160 myopic children to either Defocus Inc. Multiple Segments (DIMS) or single-vision lenses. Mean myopic progression was found to be –0.41 D in the DIMS group and –0.85 D in the control group with the mean axial elongation being –0.21 mm and 0.55 mm. While axial elongation in the control group was similar to previous studies, myopic progression was lower than the –1.26 D reported in a PAL trial by Edwards and colleagues.
According to Richdale, atropine has a long history in myopia control, but only recently has been subjected to randomized clinical trials. Shih and colleagues randomly assigned 188 children with myopia to 0.5% atropine with PALs, PALs alone or single-vision lenses. Data from this trial showed that slowing myopia progression relied on the axial length, and atropine had the greatest benefit (mean progression, –0.41 D; axial elongation, 0.22).
Chua and colleagues conducted a larger trial of 346 myopic children who received either 1% atropine or vehicle eye drops nightly for 2 years. Mean myopia progression was –0.28 D, and mean axial elongation was –0.2 mm. Treatment concluded after 2 years, and patients were followed for another year in a study by Tong and colleagues, where the atropine-treated group had a 1-year progression of –1.14 D, and the control group progressed by –0.38 D.
In 2019, Yam and colleagues used 0.05%, 0.025% and 0.01% of atropine and a placebo, showing a mean progression of –0.27 D, –0.46 D, –0.59 D and –0.81 D in each respective group with corresponding mean axial elongations (0.20 mm, 0.29 mm, 0.36 mm and 0.41 mm). These findings suggest that 0.05% atropine was most effective and slowed progression by 0.54 D, with an axial elongation of 0.21 mm.
In a randomized clinical trial of overnight orthokeratology in myopia treatment, Cho and colleagues assigned 78 children to either orthokeratology or spectacles and found the mean axial elongation to be 0.36 mm in the orthokeratology groups and 0.63 mm in the control groups. Hiraoka and colleagues and Santodomingo-Rubido and colleagues both conducted studies examining a percentage of the same participants for 5 and 7 years, finding that a difference of 0.45 mm in axial elongation was the largest average cumulative treatment effect in all myopia control literature.
Cases of microbial keratitis associated with overnight orthokeratology in children were appearing in 2001. A report by the American Academy of Ophthalmology on the safety of this method to manage myopia concluded that larger studies are needed to succinctly report the risks of treatment and risk factors for complications as well as the efficacy of overnight orthokeratology in slowing myopia in children.
Sankardurig and colleagues conducted a 2-year, five-arm randomized clinical trial to determine the efficacy of soft contact lenses in myopia management in which participants were assigned to single vision soft contact lenses, two soft lens designs to impose myopic defocus across the retina or two extended depth of focus lenses. Results showed the single vision group had myopia progression of –1.12 D, while the other groups progressed from –0.78 D to –0.87 D.
In 2019, Chamberlain and colleagues published results from a 3-year randomized clinical trial evaluating CooperVision’s MiSight 1-day dual-focus soft contact lens. In this study, investigators randomly assigned 109 myopic children to either the MiSight lens or CooperVision’s Proclear 1-day spherical lens. The MiSight group showed a mean myopia progression of 0.73 D less than the control group. Following the publication of these results, the MiSight lenses were approved by the FDA for myopia control in children.
Contact lens safety should be heightened for children. Contact lens wear can cause chronic and acute inflammatory events in the wearers due to hypoxic, toxic, bacterial or mechanical factors.
According to this review, the age of the child is the most important factor, with ethnicity playing a significant role in the rate of progression.
“Progression is faster in younger children, and possibly those of East Asian descent or geographic location and those with a parental history of myopia. It is rare to see a myopic child of recent onset who does not progress,” the researchers wrote. “Nearly all young myopes progress, which argues in favor of managing all of them, irrespective of their estimated progression rate.”
Slowing the progression of myopia in children using such treatments as spectacles, overnight orthokeratology or contact lenses will lead to long-term health benefits, according to researchers.
“Standard single vision soft contact lenses may not be recommended to myopic children and adolescents. Instead, multifocal and orthokeratology contact lenses, or other modalities proven to slow progression, may become the standard of care,” the researchers wrote. “Safety of all refractive correction and management options must also remain at the forefront of practitioners’ recommendations.”