Understanding Low Vision
Prescription eyeglasses help billions of people across the world improve their vision. In fact, when a person’s vision starts to weaken, a new eyeglass prescription is often the solution. However, prescription eyeglasses cannot correct every issue, including low vision.
The National Eye Institute (NEI) defines low vision as a vision problem that makes it hard for people to perform daily activities. People with low vision may not see well enough to read, drive, recognize people’s faces, distinguish between colors, and see their television or computer screens clearly. Although it is a serious condition, low vision does not include complete blindness and can sometimes be improved with the use of visual aids. Understanding low vision and how it can affect a person’s daily life can help patients and their families confront the condition more successfully. The four most common types of low vision are:
- Central vision loss: This is marked by an inability to see things in the center of your vision.
- Peripheral vision loss: This compromises a person’s ability to see things out of the corners of the eyes.
- Night blindness: This causes people to be unable to see in low light.
- Blurry or hazy vision: This causes blurry, hazy, and out of focus vision when viewing objects both near and far.
While there is a link between aging and low vision, low vision is not only caused by aging, but also can be caused by other diseases. Low vision affects one in four adults over age 75 and one in six adults over age 45. The type of low vision a person experiences depends on the disease or condition that caused it. These include:
- Age-related macular degeneration (AMD): AMD is a disease of the eye that can blur the vision people need to read and drive. AMD is slow to develop and as it progresses the blurry area near the center of vision may get bigger, and things may also seem less bright than before.
- Cataracts: Cataracts affect more than half of all Americans age 80 or older. Many people do not notice they have a cataract initially. But, over time, people with a cataract may notice their vision becoming blurry, hazy, or less colorful.
- Diabetic retinopathy: Diabetic retinopathy affects blood vessels in the retina, and can cause low vision in people with diabetes. Anyone with diabetes is urged to schedule comprehensive dilated eye exams at least once per year, as finding diabetic retinopathy early, even when no symptoms are present, can help people protect their vision.
- Glaucoma: Glaucoma is an umbrella term used to describe a group of eye diseases that damage the optic nerve. Half of all people with glaucoma don’t even know they have it, which only underscores the importance of scheduling comprehensive dilated eye exams.
Low vision is a serious condition that can affect people’s ability to perform daily tasks including reading and driving. More information about low vision can be found at www.nei.nih.gov.
