Myopia control is a new area of research in optometry and ophthalmology. In recent years there has been a large increase in the percentage of the population that is becoming near-sighted which is known as myopia in technical language. In the United States about 40% of the population is myopic. In some Asian countries as much as 90% of the population is myopic.
The increase in myopia is due in large part to a change in lifestyle with more time indoors and more time looking at electronic device screens. The lack of exposure to direct sunlight and the prolonged stress of looking at an electronic screen appear to be major factors in triggering the growth of the eye to become longer and more myopic.
There are reasons to be concerned about this increase in myopia in our population. As the amount of near-sightedness increases the incidence of a number of eye diseases also increases. There is a known increase in the risk of cataracts, macular degeneration, retinal tears and retinal detachments. It also means dealing with ever increasingly thick lenses in glasses and contact lenses. As myopia progresses it can grow past the level that is safe to treat with laser vision correction.
There are some ways to decrease the risk of increasing myopia with changes in lifestyle. These include spending more time outdoors and decreasing time spent looking at electronic screens.
There are three treatment options that have been shown by numerous research studies on humans and laboratory animals that also significantly slow the progression of myopia. These are orthokeratology, bifocal soft contact lenses and long-term use of atropine eye drops. These options are currently not specifically labeled by the FDA for use in myopia control but they are under investigation by the National Institute of Health in clinical trials.
Orthokeratology is a method of fitting rigid lenses to reshape the cornea to correct the refractive error. These lenses are typically placed into the eye at bedtime and taken out up waking. The front of the eye is reshaped by moving tissue from the center to the periphery of the cornea. The new shape effects the way light enters the eye in the periphery in a way that is beneficial in slowing the progression of near-sightedness as well as correcting the central vision. This was found by accident when children who were having their vision corrected by orthokeratology were found to have a greatly reduced rate of change in their myopia.
Some multifocal contact lenses have refractive properties that are somewhat similar to the shape of the eye that has undergone orthokeratology. The way that the multifocal lenses changes the peripheral vision also slows the progression of myopia. Since the lenses must be put into the eye to get this effect skipping days of multifocal contact lens wear decreased the effectiveness of this form of myopia control.
The third method is prolonged use of the atropine eye drops. These drops are only available in 1% strength in prepacked formulas. They are approved by the FDA in infants but it has significant side effects of causing blurred vision, an inability to focus at near and light sensitivity with pupil dilation.
Research on atropine dosage has shown that a very dilute, 0.01% atropine, that is one hundredth of the strength of the solution in the prescription bottle, produces an equal decrease in the rate of myopia progression with virtually no decrease in focusing ability, no increased light sensitivity and no problems with blur. This dilute strength must come from a compounding pharmacy and it is more expensive as a result.
As long as I have been in practice I have experienced young patients who have ever increasing near-sightedness. There has been no way to slow this change in the past. Now there are now three methods that should be considered for every child who is experiencing increasing myopia. The end result is a life with a less strong lens correction and less risk of serious eye disease.
Dr. Wheatall looks forward to discussing these myopia control options with you.
Myopia: A close look at efforts to turn back a growing problem. The NEI funds research to slow the increase in nearsightedness.
Treatment Options for Myopia, Jane Gwiazda, PhD, FAAO
Controlling myopia progression in children and adolescents, Molly J. Smith and Jeffrey J. Walline
Bifocals & Atropine in Myopia Study (BAM)