Nearsightedness, known as Myopia, is one of the most common vision problems.
Myopia, has increased by 66 percent since 1970-1971 according to a National Eye Institute (NEI) study that compared rates of myopia in the USA with a survey conducted 1994-2004. The rate of myopia rose from 25 percent of participants to 41.6 percent. According to Susan Vitale, NEI epidemiologist of ocular diseases and vision disorders who led the studies, “The good news about myopia is that it is easy to treat.”
Nearsighted people have difficulty reading signs and clearly seeing distant objects, but they can see up-close tasks such as reading or sewing, just fine.
What Is Myopia Control?
Traditional methods of “correcting” myopia utilize optical techniques to focus for the amount of myopia one already has. This may be eyeglasses, contact lenses, or refractive surgery such as LASIK. These methods do not help prevent further increases in myopia.
Myopia Control utilizes different techniques to arrest or slow the development of myopia from increasing or becoming worse. In other words, slowing the myopia such that your eyeglass lenses or lens corrections powers don’t keep increasing in power.
Why should you be interested in Myopia Control?
Because slowing the progression of myopia may keep your child from developing high levels of nearsightedness that require thick, corrective eyeglasses. Higher amounts of myopia are associated with serious eye problems later in life, such as early cataracts, glaucoma, myopic macular degeneration, and retina detachments.
Currently, three types of treatment are used for controlling myopia in the US.
- Atropine eye drops
- Multifocal contact lenses
- Orthokeratology ("ortho-k")
Here's a summary of each of these treatments and of recent myopia control research:
Atropine Eye Drops
Atropine eye drops have been used for Myopia Control for many years, with effective short-term results. Recent research has shown that the dosage or strength of the Atropine used in the past was too strong. Today we use dilute concentrations of Atropine to slow the progression of myopia. These weaker concentrations also minimize Atropine side effects such as focusing difficulties and light sensitivity, photophobia, while using the Atropine. The weaker concentrations also appear to be more effective in controlling myopia than the stronger concentrations.
How Does Atropine Work?
It is believed the progression of myopia may occur due to increases in the length of the eye from front to back (axial length). It appears Atropine helps arrest the lengthening of the eye.
Results of the studies of Atropine eye drops to control myopia progression have been impressive and more studies are being done. One study (5 yrs.) has shown a definite positive effect in slowing myopia progression using low dose Atropine. Some short term studies have shown Atropine produced an average reduction of myopia progression of 81 percent among nearsighted children.
Orthokeratology is the use of specially designed gas permeable contact lenses that are worn during sleep at night. These special contact lenses temporarily correct nearsightedness and other vision problems so that glasses and contact lenses aren't needed during waking hours.
Evidence suggests nearsighted children who undergo several years of orthokeratology may end up with less myopia as adults, compared with children who wear eyeglasses or regular contact lenses during the peak years for myopia progression. Some of the early studies also suggest that the Myopia Control effects may last longer than the Atropine method for Myopia Control.
How Does OrthoK Work?
It appears that the wear of these lenses overnight help control myopia by slowing the elongation of the eyes. Elongation of the eyeballs (from front to back) is associated with myopia progression. You control the elongation, you control the myopia progression.
Multifocal Contact Lenses
Multifocal contacts are special lenses that have different powers in different zones of the lens to focus for presbyopia correction combined with nearsightedness or farsightedness (with or without astigmatism). Basically this type of contact lenses has been used to correct mature adult vision problems (ages 40 years and older). They had not been used to control children’s myopia.
How Does This Work?
Again, the use of specific multifocal contact lens designs for children slow the lengthening of the eye and therefore the myopia.
Who Should Consider Myopia Control?
We recommend parents consider Myopia Control for Asian children with myopia, for children with myopia and a family history of high amounts of myopia (Mom, Dad, or Siblings), and for any myopic child who is showing increases in myopia of 0.50 diopter or more from their previous, last, lens prescription.