Between 5 and 10 percent of Americans are far-sighted, including children. Deciding whether these children should have their vision corrected with glasses isn't always a simple decision, however. This article looks at some of the factors affecting this decision.
Most people are familiar with myopia, or nearsightedness. Individuals with myopia have eyes that are too long, meaning that light entering the eye focuses before it reaches the retina. Someone with myopic vision may be able to see things that are close clearly, but struggle to resolve things that are further away.
It may come as a surprise, then, to realize that being far-sighted isn't necessarily the opposite of being near-sighted. Someone who is far-sighted doesn't necessarily see things clearly at a distance but fuzzy up close. In fact, they may even have 20/20 vision. Instead, someone who is diagnosed with farsightedness, or hyperopia, simply has an eye that is too short meaning that light would focus naturally behind the retina.
So why can someone with hyperopia can often still see clearly? It's because the eye has a mechanism in place to help pull the focal point up to the retina. This is called accommodation and is the same muscle movements that help a person move their focus from something far away to something close. Most children are born at least somewhat far-sighted, but are able to use accommodation to compensate until their eyes mature during the teenage years.
Although most children are able to rely on accommodation to bring things into focus, sometimes glasses are still necessary to treat hyperopia.
Keep Eyes Straight
One reason a child with hyperopia may need glasses is if the degree of farsightedness causes eye crossing, also known as accommodative esotropia. In these cases, glasses are needed not to correct the hyperopia, but to keep the eyes straight.
In some cases, the degree of hyperopia is significant enough that a child can not rely on the accommodation mechanism to correct it. While accommodation is generally effective through a prescription of +1 or even +2, beyond that it may not be possible for a child to see things clearly. Because vision is critical for learning in young children, any condition that results in a child having difficulty seeing should be corrected.
Also known as "lazy eye," amblyopia occurs when the brain "turns off" visual signals from one eye. If a child is significantly more far-sighted in one eye compared to the other there is the risk that the brain will come to rely too much on the "good" eye, leaving the other to atrophy. Correcting vision in the hyperopic eye can prevent this from happening.
Not every case of farsightedness in children requires glasses. Use the information in this article to better understand why your child may or may not require prescription glasses to improve their vision.