Vision Problems

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KEY POINTS

• Low vision means that you have vision problems that cannot be corrected with glasses, contact lenses, medicine, or surgery. You may have vision problems such as loss of part of your visual field, loss of color vision, or severe problems with glare or low light.
• Your provider may recommend that you use large-number phone keypads, large type in books and ebooks, magnifying glasses or software to magnify screens and mobile phones, or other kinds of vision aids.

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What is low vision?

Low vision is vision problems that cannot be corrected with glasses, contact lenses, medicine, or surgery. If you have low vision, you may have trouble driving, reading, or using the computer. You may have vision problems such as loss of part of your visual field, loss of color vision, or severe problems with glare or low light.

What is the cause?

There are many possible causes of low vision, such as:

• An eye disease you were born with
• Injuries from car accidents, sports, falls, or being punched or kicked in the eye
• Optic neuropathy, which is damage to the optic nerve, which carries visual messages to the brain
• Macular degeneration, which is a disease that damages the macula in your eye. The macula is in the center of the retina. The retina is the lining at the back of the eye that senses light coming into your eye. The macula allows you to see fine details in the center of your field of vision.
• Diabetic retinopathy, which is when abnormal blood vessels form in the back of the eyes of people with diabetes. These blood vessels are not strong and can bleed.
• Glaucoma, which is an eye disease that damages the optic nerve. This is usually caused by high pressure inside your eye.

What are the symptoms?

Symptoms may include:

• Seeing spots or having blurry vision that makes it hard to recognize faces of friends or relatives, or to read things like street signs or food labels
• Trouble seeing close up when you cook, sew, or do household repairs
• Needing bright light to see indoors and outside
• Having problems judging how far away things are, which may cause you to stumble on stairs or knock things over

How is it diagnosed?

Your eye care provider will ask about your symptoms and medical history and do exams and tests such as:

• An exam using a microscope with a light attached, called a slit lamp, to look closely at the front and back of your eye
• An exam using drops to enlarge, or dilate, your pupils and a light to look into the back of your eyes
• An ultrasound, which uses sound waves to show pictures of your eye
• Blood tests
• CT scan, which uses X-rays and a computer to show detailed pictures of the bones and tissues around your eye

How is it treated?

Because low vision cannot be treated with ordinary glasses or contact lenses, your provider may recommend that you use vision aids. Tools that can help include:

• Large-number phone keypads and watch faces
• Filters to reduce glare on computer screens
• "Talking" clocks or scales
• Audio books, magazines, or newspapers or machines that "read" printed material aloud in a computer voice
• Using large type printed books or enlarging the type size in an eReader (electronic devices such as iPads, Nooks, or Kindle)
• Personal computer hardware such as lighted keyboards, large type, and software that magnifies screens and converts text to speech for both computers and mobile phones
• Closed CCTV systems that use video cameras and large TV screens to enlarge reading material, medicine bottles, or pictures
• Magnifying eyeglasses, hand-held magnifiers, or stand magnifiers to enlarge your reading material or other objects

How can I take care of myself?

Learn what you can about low vision devices that may help you. If you can, try out a product before you buy it. Also, remember the simple things you can do to help you see better:

• Sit close to the TV or hold reading material close to your eyes.
• Use enough light. Even people with no eye problems need about twice as much light at age 60 as they did at age 20 for the same task. Also, wear a visor to block overhead light or special lenses to reduce glare.

Information is also available from many public and private agencies that help people with low vision. You may be eligible for special benefits such as tax relief, phone discounts, and free audio books. Some of these agencies are:

• American Foundation for the Blind
  800-232-5463
• National Association for the Visually Handicapped
  212-889-3141
• National Center for Vision and Aging
  800-334-5497
• National Library Service for the Blind and Physically Handicapped
  800-424-8567
• State government agencies for the visually impaired