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If you are visually impaired it doesn't necessarily mean you are blind.

The terms low vision, partially sighted ,legally blind, and totally blind are used to describe people with vision impairments.

Low vision is defined as a visual impairment severe enough to interfere with successful performance of activities of daily living (ADLs) although some usable vision is retained. The WHO (World Health Organization) offers the following definitions of low vision, using standard measures of visual acuity and field diameter:

  • Moderate visual impairment: Best corrected visual acuity is less (worse) than 20/60 (including 20/70 to 20/160).
  • Severe visual impairment: Best corrected visual acuity is less than 20/160 (including 20/200 to 20/400) or visual field diameter is 20 or less.
  • Profound visual impairment: Best corrected visual acuity is less than 20/400 (including 20/500 to 20/1000) or visual field diameter is 10 or less.

The categorization of visually impaired persons into a legally blind/legally sighted dichotomy may inappropriately limit access to public benefits. Some who fall under the diagnostic category of legally blind could function highly, while others who are categorized as legally sighted could have a greater need for services because of comorbidities or socioeconomic or other factors. Therefore, those with the greatest need for services may not be eligible for public benefits because they do not meet diagnostic criteria.

Low vision can result from a variety of ophthalmologic and neurologic disorders. The most common causes of low vision in the United States include:

In addition, a number of other diseases, such as stroke, head injury, or tumors may result in conditions such as field cuts or visual neglect, in which individuals never see a certain portion of the visual field or in which the brain does not perceive half the visual world (i.e., a person with left visual neglect will not even be aware that they are unable to see the left side of the world).