In the previous blog post, we reviewed the most foundational treatment for progressive myopia or nearsightedness being behavioral modification. Spending more time outside, less time on (and more distance away from) screens and taking more breaks are all important. The next treatment of childhood progressive myopia is optical in nature. Translated, this means providing vision correction to kids in the form of glasses and/or contacts. The following video from EyeSmart provides a quick refresher:
At present, consensus suggests full correction of the distance refraction with frequent upgrades to a new fully corrected glasses as the minimum standard of care. Appropriate screening and then close monitoring of these young patients by eye care professionals is critical. Though when a child's myopia worsens quickly, we are now able to provide some optical treatments aimed at slowing the rate of decline. Rapid progressors tend to be kids who are progressing faster than 0.5D per year. "Some clinicians favor single vision glasses or contact lenses, some bifocal or progressive glasses or contact lenses, some orthokeratology, and more specialty glasses and contact lenses specifically designed for the management of progressive myopia are becoming available every year." Dr. Richard Lindstrom on healio.com).
For instance, ortho-K lenses are appealing to patients who do not want to wear glasses or contact lenses during the day. Ortho-K lenses are worn overnight to flatten the central cornea and temporarily reduce a specific amount of myopia while the patient sleeps. These dual benefit lenses provide clear vision without the need for vision correction during the day, and they also reduce myopic progression in children. Ortho-K lenses slow axial length growth compared with single vision gas permeable contact lenses, single vision soft contact lenses and single vision spectacles. Studies supporting the safety and efficacy of this treatment are available, and as the incidence of myopia increases and the realization that, if left untreated, myopia can culminate in serious vision-threatening diseases, ortho-K is gaining the global gravitas that eluded it earlier in its evolution.
There have long been concerns about microbial keratitis with respect to ortho-K lenses because they are worn overnight. These concerns are worth respecting, but the incidence is low, especially with good care and careful hand washing techniques. According to a recent study, the risk for microbial keratitis appears similar to rates associated with daily wear soft contact lenses. It is also worth considering that unlike extended wear contact lenses, ortho-K lenses are not being worn during the day, exposing the eye to normal oxygenation. When ortho-K lenses are handled properly, the benefits outweigh the risks.
In contrast to ortho-K lenses, soft multifocal contact lenses are worn during the day. Soft multifocal contact lenses, like ortho-K, are theorized to slow myopic progression by creating myopic defocus in the periphery, which sends a “signal” to slow eye growth. Soft multifocal contact lenses have been shown to slow the progression of myopia in children by nearly 50%, which is similar to ortho-K lenses.
Myopia control experts suggest that myopia management spectacles may be appropriate for patients — or their parents — who are not yet ready to commit to contact lenses. While soft multifocal contact lenses and ortho-K have been shown to have better myopia control efficacy than progressive addition and bifocal spectacles, innovative spectacle lens technology for myopia control, such as those that rely on a peripheral defocus theory, whereby the peripheral retina receives myopic defocus as a slow down or stop signal for eye growth, is worth exploring (keeping in mind that myopia management-specific spectacles are not yet FDA approved).
So the good news is that eye care providers have more tools to slow down myopia than we did even a few years ago. However, the right fit for your child is one that is 1) effective 2) safe 3) convenient and 4) affordable. Therefore, customizing treatment for your child so that they can be successful in the long-term is as much an art as a science. You can find more on myopia control and the optical options we offer here. In part 3, we will discuss prescription eye drops to slow the growth of the eye.