Severe visual impairment and blindness are complex symptoms that can be caused by a variety of genetic disorders, injuries or health conditions that develop over time. In some cases, congenital blindness is a birth defect that leads to a child being born with visual impairment or without the ability to see at all. In other instances, diseases like macular degeneration, glaucoma, diabetic retinopathy and cataracts can rob people of their sight over time.
In the past, blindness was often viewed as a condition that people simply had to live with. But medical advances and a growing volume of research have indicated that many causes of visual impairment can be detected and corrected before they lead to total vision loss. This is true even in infants, though diagnosing and treating the problems in these populations is more difficult.
Causes of Blindness
Most of the time, blindness that's present at birth is due to some form of genetic abnormality that leads to problems such as congenital cataracts or infantile glaucoma, among others. But other forms of blindness happen gradually, often by leaving a visual problem untreated until it progresses to major visual impairment.
Cataracts, which cause a general blurring of the lens of the eye, cause more blindness throughout the world than any other condition. Glaucoma, in which fluid pressure builds up over time in the eye, is another common cause. Age-related macular degeneration, or AMD, often robs central vision from adults over the age of 60. Finally, blindness is often tied to the disease diabetes. Over time, diabetes affects blood flow throughout the body, and the retina of the eye is often one victim, in this instance in the form of diabetic retinopathy.
Many people with blindness can lead active and fulfilling lives, but they will probably need training and education in order to live better with their condition. This includes instruction in basic life skills like learning how to get around safely and communicate and read using Braille, for example.
If a person is at risk for blindness or vision impairment because of a disease, the best weapon against this is a regular eye examination. These exams can help detect problems and treat them before they progress too far down the road.
SOURCES: U.S. National Library of Medicine; Middle East African Journal of Ophthalmology; National Federation of the Blind
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