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Vision Impairment and Blindness

What is vision impairment?

Vision impairment is the loss of vision. It includes blindness, which means that you have lost all or most of your sight. It also includes low vision, which means you have some vision, but the vision loss makes it hard to do everyday activities. You may have trouble reading, shopping, cooking, writing, and watching TV. Low vision can't be fixed with glasses, contact lenses, medicine, or surgery.

What causes vision impairment?

Aging doesn't cause vision loss on its own. But many diseases that are more common in older adults can cause it. The leading causes of low vision and blindness in the United States are age-related eye diseases such as macular degeneration, cataracts, and glaucoma. Other eye disorders, eye injuries, and birth defects can also cause vision loss.

How is vision impairment diagnosed?

Vision impairment is diagnosed with a dilated eye exam. Early warning signs of a vision problem can include not being able to see well enough to:

  • Do everyday tasks like reading and driving
  • Recognize people's faces
  • Tell the difference between colors
  • See the television or computer screen clearly

You can have these symptoms even though you are wearing glasses or contacts.

What are the types of low vision?

There are several types of low vision. Which type you have depends on the condition that caused your low vision.

Common types of low vision include:

  • Central vision loss (not being able to see things in the center of your vision)
  • Peripheral (side) vision loss (not being able to see things out of the corners of your eyes)
  • Night blindness (not being able to see in low light)
  • Blurry or hazy vision
What are the treatments for low vision?

Low vision is permanent. Glasses, medicine, and surgery can't cure low vision. But sometimes they can improve your vision, help you do everyday activities more easily, or keep your remaining vision.

Your treatment options will depend on the condition that caused your low vision. Ask your eye doctor which treatments might help you. They may recommend vision aids or vision rehabilitation, which might make everyday activities easier.

Vision rehabilitation teaches you how to live with your vision loss. It may include:

  • Showing you how to use a magnifying device or screen readers for reading
  • Helping you set up your home so you can move around more easily
  • Employment and job training
  • Assistive devices, like lighting and reading stands

Your provider may suggest other resources, such as transportation and household services, to help you cope with your vision loss.

How can I make the most of my remaining sight?

The sooner vision loss or eye disease is found and treated, the greater your chances of keeping your remaining vision. Whatever the cause, lost vision cannot be restored. But it can be managed. A loss of vision means you may have to reorganize your life and learn new ways of doing things. Your provider may make suggestions to help make life easier. These may include:

If you have some vision:

  • Visual aids such as magnifiers
  • Telescopic glasses or monoculars for seeing distance
  • Large print books
  • Clocks with larger numbers
  • Brighter lights
  • Anti-glare sunglasses or glare shields

If you have no vision (blindness):

  • Devices like text-reading software and braille books
Can vision impairment be prevented?

You can help take care of your vision by:

  • Having regular comprehensive eye exams by an eye care professional
  • Wearing sunglasses and protective eyewear to protect your eyes
  • Making lifestyle changes to lower your risk of health conditions that can cause vision problems:
    • Getting regular physical activity
    • Staying at a healthy weight
    • Quitting smoking (or not starting)
    • Eating a healthy diet

NIH: National Eye Institute




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