Loss of sight is a common cause of disability with significant impacts on mobility and activities of daily living (ADL). The most common causes of visual impairment in adults are cataracts, glaucoma diabetic retinopathy and macular degeneration. In child the most common causes are congenital.
Classified as central or peripheral deficits.
Legal blindness – defined in Social Security Act (USA) as visual acuity of < 20/200 in the better eye; visual field of < 20 degrees in better eye. Definition of legal blindness is somewhat arbitrary, but is used for criteria as access to social services.Vision enhancement methods (IMAGE): Illumination devices Magnification Altered contrast Glare reduction Expander of visual fieldAdverse outcomes associated with visual impairment: Reduction in functional ability; reduced quality of life; social isolation loneliness; falls; accidents; depressionVision substitution methods: Canes; guide dogs; sonic devices; braille books; talking books; talking watches and other devices; computer aided systemsTips for working with the visually impaired: avoid startling them stand in front of them when speaking to them diffuse bright light is better minimise distractions clearly identify yourself make it clear when you enter or leave room narrate any actions provide large print instructions if needed