What types of visual impairment are there?
Blindness can be congenital and hereditary. It can be caused by disease. It can be the result of an accident. It can even be a manifestation of mental illness. The most common cause of blindness in the United States is a disease called glaucoma, in which pressure builds up in the eye and that pressure damages it. The largest single group of adults of working age lost their sight due to diabetes. Most visually impaired seniors have age-related macular degeneration (ARMD), in which the part of the eye with the highest density of light receptors deteriorates and central vision is destroyed. The following are all examples of visual impairment: • No vision at all • Perceive only light • Perceive only vague shapes • Perceive shapes and some color • Very blurry and indistinct • Consistently or randomly miss parts of an image • Unable to see detailed images, such as print, without magnification • Any level of vision but only a narrow view, like looking through a tube You can see a diagram of t
