New contact lenses may help slow the progression of nearsightedness in children.
Myopia (nearsightedness) is becoming increasingly prevalent in the United States and throughout the world. A recent multi-year study found that 41.6 percent of Americans were nearsighted in 1999 to 2004, up significantly from 25 percent in the early 1970s.
The primary cause of myopia progression in children appears to be axial elongation (lengthening) of the eyeball. Some researchers believe the key to slowing myopia in susceptible children is found in how light is focused in the peripheral retina.
Eye doctors prescribe glasses or contact lenses to correct a person’s central visual acuity — vision that can be tested with an eye chart. But conventional glasses and contacts that correct central vision actually cause a slight degree of farsightedness in the peripheral retina that may stimulate the progression of myopia from year to year, researchers say.
At this year’s annual meeting of the Association for Research in Vision and Ophthalmology (ARVO), researchers presented data that shows specially designed gas permeable contact lenses that alter how light is focused in the peripheral retina (similar to lens designs used for orthokeratology) can reduce elongation of the eye that causes myopia progression in children.
Other research suggests special soft contact lens designs also may be effective in slowing myopia. One study suggests soft bifocal contact lenses with a center-distance design may help curb the progression of nearsightedness in children. Other soft contact lens designs to control myopia also are being investigated.
One new silicone hydrogel contact lens design being developed in Australia is showing promising results. Nearsighted children between the ages of 7 and 14 who wore the lenses for six months had 54 percent less progression of myopia than similar children who wore only eyeglasses for the same period.
These and other studies suggest that soon a number of contact lens designs may be available to help eye doctors manage the progression of myopia in children, rather than simply prescribing significantly stronger eyeglasses or contacts every year, say researchers involved in the field.
For the latest information about contact lenses and myopia control, consult your eye doctor.
Resources:
- Increased prevalence of myopia in the United States between 1971-1972 and 1999-2004. Archives of Ophthalmology. December 2009.
- Slowing down myopia with contact lenses. Contact Lens Spectrum. December 2010.