Vision Impairment, or Blindness

Blind people cannot see.
Some can see just a little bit.
Some can't see anything.
There are ways to help blind people get around.
Blind people read by feeling dots.

Our eyes work to give us sight.
To find out how our eyes work, go here: http://www.stlukeseye.com/Anatomy.asp

However, not everyone can see. Some people suffer from vision impairment.

Vision impairment means a partial or total loss of vision. People can have very limited sight, and be called 'legally blind'. This means that they have such limited vision that it causes them similar difficulties to that of a blind person.

There are many causes of vision impairment. Worldwide, a lack of vitamin A is the leading cause of blindness.

Other common causes:
ACCIDENTS that damage the eyes, such as chemical burns or injuries from fireworks, fishing hooks, being hit by flying objects, sport, car accident or head injury and others.

DIABETES : about 1 in every 3 diabetics develops diabetic retinopathy (say it like this: rett-in-op-ath-ee), and in severe cases can lose their sight. This happens when there are changes in the tiny blood vessels in the retina, and these may burst. The retina may even break loose from the back of the eye. Laser surgery can help to seal leaking blood vessels if done early enough.

CATARACTS: Clouding of the lens are called cataracts (Say: cat-uh-racts). When they form, they block the light from passing through the eye. Some people are born with cataracts, but generally cataracts develop later, particularly as people get old. They are not painful. Cataracts large enough to cause serious vision problems are operated on.

GLAUCOMA (say glor-comb-uh): When the clear fluid inside the front part of the eye does not drain normally, pressure builds up in the eye. This can damage the eye and result in blurred vision, a narrow 'tunnel' of vision, and eventually total blindness. In severe cases, as the eye pressure builds, it can become very painful. In the severe kind, there is great pain as eye pressure builds. Generally, the condition can be controlled by medicine, but sometimes surgery is necessary.

MACULAR DEGENERATION: The macula is the part of the retina that forms the centre and clearest part of the picture we see. There can be a breakdown of the retina, especially as people get old. This breakdown can be fast or slow. The vision around the edges generally remains good. Sometimes surgery can help repair weak spots in the macula or by removing worn out tissue and allowing new tissue growth.

RETINITIS PIGMENTOSA - This often begins by 'night blindness' when a person, often a child, has difficulty seeing at night and in poor light. This develops into 'tunnel vision'. Vision loss increases until the person is legally blind, sometimes totally blind. Some people with Retinitis Pigmentosa has a tiny patch of vision in good light. This condition is inherited.

There are many other causes of blindness that are less common than these.

Sometimes a person is born blind, when they have a condition that prevents the correct development of part of the eye. Sometimes a baby that is born very early can become visually impaired because the eye structure is not yet fully developed or strong, and damage may occur.
 

Daily Life for Visually Impaired People

For people who are visually impaired, daily tasks are made more difficult. Think about dressing yourself, making food, pouring a cup of tea and other daily tasks. These are complicated by a lack of vision. Blind people have to learn how to do these tasks, and become very good at doing them.

Blind people take part in sports too. Here, a sighted skier is leading a blind skier.

People who are visually impaired can have a guide dog to help them get around, but some use a special cane instead. Guide dogs are permitted to go anywhere: public transport, libraries, shops, offices. When wearing the special harness, the dog knows it is working. The dog waits quietly while its owner is busy.

There is an alphabet for the blind called Braille, made up of raised dots. It was invented by Louis Braille. Blind people read with their fingertips as they feel the dots. Computer keyboards can have Braille dots on the keys so that blind people can type, and special word processors print in Braille. Other machines such as ATMs often have Braille dots on the number pad keys.

See Braille : http://www.omniglot.com/writing/braille.htm

Find out about Fred Hollows, a famous Australian who was a pioneer in helping people in poor communities who had treatable vision impairment:
http://www.seeaustraliarun.com/hollows/fred_hollows.shtml