Range of myopia treatments expanding
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The thought that progressive myopia is a “disease” that deserves treatment is itself controversial. To add to the controversy, there is much debate concerning what constitutes appropriate treatment.
I am not a pediatric ophthalmologist, but I have been following this area carefully for decades and will share a few personal thoughts.
The now-deceased John Allen Dyer, MD, was treating progressive myopia with 0.5% to 1% atropine drops and bifocal eyeglasses at the Mayo Clinic 45 years ago when I was in training and on the faculty at the University of Minnesota department of ophthalmology and visual neurosciences. I sent him a few patients, and most found the side effects of the treatment unacceptable and discontinued therapy. Nonetheless, his pioneering work, data and clinical experience were convincing that therapy with strong atropine drops and the required bifocal spectacles was effective at reducing the rate of myopia progression in children. The consensus opinion of most ophthalmologists at the time was that progressive myopia was not a disease and did not require more than optical correction, but Dr. Dyer and many of his patients disagreed.
When I began research into corneal refractive surgery as a surgeon in the NEI-funded Prospective Evaluation of Radial Keratotomy study in the early 1980s, the incidence of myopia in America was approximately 25%. Today, 40 years later, it is 42% and climbing. In Asia, the incidence of myopia exceeds 80% in select countries. Most believe this significant increase in myopia is related to increased near demands placed on the optical systems of children and young adults, although other theories abound, including reduced exposure to natural outdoor lighting.
The onset is usually at age 5 to 6 years, when near demands accelerate in school, and stability is often delayed until postgraduate education is completed at age 26 years or more. To simplify my own thinking, I define the at-risk period for progressive myopia as age 6 to 26 years. This means therapy might need to continue for as long as 20 years to have maximum effect. Thus, the therapy or therapies must be extremely safe and have minimal impact on quality of life.
We have many challenges in treating progressive myopia. First, we must diagnose the patient early, at age 5 to 6 years, and capture them in an interested and trained eye care provider’s (ECP) practice. Once captured, a treatment regimen that could last as long as 20 years must be initiated. This will require significant chair time, patient/family education, a motivated patient/family and strong ECP-patient rapport.
I like to divide potential therapy into three categories: behavior/environment modification, optical treatment and pharmaceutical therapy. As a baseline treatment, we have learned that 1 to 2 hours of outside activity daily retards the rate of myopia progression. This is a win in every way for the young progressive myope and can be strongly encouraged by the ECP and parents. In addition, the so-called 20/20/20 rule, which advocates that every 20 minutes of intense near work should be accompanied by 20 seconds of gazing at a distant object more than 20 feet away, is supportable. I personally also find the 20/20/20 rule beneficial in reducing the symptoms of digital eye strain/computer vision syndrome in older adults, along with blinking exercises, high energy light filtration and dry eye therapy. To make the 20/20/20 rule easy for children and adults, their desks or workstations need to be placed in front of a window rather than a wall so distance gazing is simplified. I have personally done this with my own workstations.
The base of the treatment pyramid is behavior/environment modification, and this can be recommended to every progressive myope. The next level is appropriate optical treatment. Here we have learned, to the surprise of many, that full correction for distance is better than mild undercorrection. Thus, children and young adults with progressive myopia should be reexamined at regular intervals and their glasses/contact lens prescription continuously upgraded to full correction. The evidence supporting the use of bifocal glasses is mixed, and at this time, I personally do not recommend them. The patient with progressive myopia often will manifest significant convergence insufficiency as well, and the use of base-in prisms may be helpful. Premium eyeglasses with supporting data are becoming available, including the Essilor Stellest, SightGlass Vision spectacle lenses and Neurolens for the patient with convergence insufficiency.
As children age, many will want to be fit with contact lenses, and specially designed contact lenses such as the CooperVision MiSight and Johnson & Johnson Vision Acuvue with HydraLuxe, along with others from Alcon and Bausch + Lomb, are showing promise. In addition, orthokeratology has credible evidence confirming its efficacy in retarding myopia progression. As always, the risk-benefit ratio of contact lens wear and orthokeratology needs to be personalized for each patient.
As described in the accompanying cover story, a few pediatric ophthalmologists are offering select patients corneal and even lens-based refractive surgery, usually excimer laser PRK or a phakic IOL. The impact of refractive surgery on the rate of myopia progression is unknown, and the need for one or more re-treatments over a potential 20-year period of myopia progression remains a concern, but select patients who cannot wear spectacles or contact lenses can benefit significantly from refractive surgery. There will be many more advances in specialty contact lenses and spectacles as significant human and financial capital is being invested in this field.
Finally, we have the pharmaceutical therapy of progressive myopia. Today, this is limited to low-dose atropine in the 0.01% to 0.1% range. In early studies, efficacy seems higher with higher-concentration atropine, but as Dr. Dyer taught us years ago, the side effects of pupil dilation and loss of accommodation can have a meaningful negative impact on patients’ quality of life. We do not as yet have an FDA-approved and labeled atropine drop to treat progressive myopia, but reliable experts report that more than 800,000 children and young adults have been treated in the U.S. alone with specialty pharmacy compounded drops on a doctor’s prescription.
In conclusion, I personally believe it is appropriate to offer the progressive myope treatment. To do so, we must first capture them in an ECP office at an early age, ideally age 5 to 6 years. We can then educate the patient and family regarding behavior and environment modification, including increased outdoor play time and the 20/20/20 rule. We can also see that they are fully corrected with glasses or contact lenses, and as they age and we learn more, we can offer them specialty spectacle and contact lens correction when affordable. Finally, for the ECP comfortable with specialty compounded pharmaceuticals, dilute atropine drops are available today. Fortunately, several companies are investing heavily to bring us an FDA-approved atropine drop to retard progressive myopia. The management of refractive errors, including myopia, presbyopia and even irregular astigmatism, with eye drops is in its infancy, but I predict they will become a significant part of our practices in the next decade
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