November 7, 2019
Understanding Disability: Blindness and Low Vision
by Amber Carlton
When many of us think about blindness, we imagine someone who is totally without sight. So it may surprise you that only 15% of people with vision disorders are completely blind. The remaining 85% do retain some degree of sight.
There are a number of definitions and categories developed by ophthalmologists and optometrists, as well as the U.S. government, to classify a person’s level of visual disability.
Using the Snelling Eye Chart (the standard eye vision chart that most of us are familiar with), eye specialists measure a person’s distance acuity. Individuals who are diagnosed with low vision have a visual acuity measurement of 20/70. That means that they see the same thing from 20 feet away that a person with unimpaired vision sees from 70 feet away. Many eye care professionals consider people to have low vision only if they have permanent, uncorrectable vision loss that interferes with daily activities.
Legal blindness is a definition developed by the U.S. government to determine eligibility for various training and benefits programs. There are two parts to this definition:
- A visual acuity of 20/200 or less in the better-seeing eye with best conventional correction (regular glasses or contact lenses).
- OR a visual field (the total area an individual can see without moving the eyes from side to side) of 20 degrees or less (also called tunnel vision) in the better-seeing eye.
Most people with vision loss are still able to differentiate between light and dark, and determine the direction or source of the light. For people with total blindness, however, there is a complete lack of light and form perception, which is recorded as no light perception (NLP).
The Independence Center offers people who have blindness or low vision a variety of resources – including peer support groups, skills classes, and assistance with disability benefits – to help them live more independently.
To get started, visit our Low Vision & Blindness page or give us a call at 719-476-8181.