Before getting into the myths and facts of low vision, let’s define some terms that are often confused in this area of specialty.
• Visual impairment: According to the American Optometric Association, visual impairment is a functional limitation of the eye(s) or visual system & can manifest as reduced visual acuity or contrast sensitivity, visual field loss, photophobia, diplopia, visual distortion, visual perceptual difficulties, or any combination of the above.
• Legal blindness: In the US, legal blindness is defined as best corrected VA 20/200 or worse in the better seeing eye and/or peripheral vision worse than 20 degrees in both eyes.
• Low vision (but not legal blindness): In the US, low vision is generally considered as best corrected VA of 20/70 to 20/200 (in most cases, someone with this level of vision cannot get an unrestricted driver’s license).
• Complete blindness: No vision at all, also known as No Light Perception.
The following are a few myths and facts about low vision that will allow the student clinicians to better understand and work more effectively with patients with visual impairment.
Myth: Strictly looking at visual acuity, patients with 20/20 VA in one eye and No Light Perception in the other eye are considered legally blind.
Fact: Legal blindness is an impairment in BOTH eyes (we always consider the better seeing eye).
Myth: Individuals with visual impairment or those considered legally blind always use a white cane.
Fact: A person with low vision may use a white cane in specific situations, but many do not rely on a cane for mobility guidance. [2]
Myth: People with visual impairment cannot live independently.
Fact: Regardless of one’s level of visual loss, it is not a barrier to living a free and independent life. [2]
Myth: People who have low vision are unable to drive.
Fact: Currently, over 25 states allow individuals with low vision to have a restricted driver’s license. Many may require the patients to use a bioptic telescope while behind the wheel. Eligibility requirements vary by states. [2]
Myth: Individuals with low vision must read Braille because they are unable to read regular print.
Fact: The type of print patients with low vision read varies. Some use Braille, others use larger fonts,and there are those who read normal size print with an optical device. [2]
Myth: Low vision patients are born with their impairment.
Fact: Some diseases may cause visual impairment at birth (albinism, aniridia). Others are acquired later in life, such as age-related macular degeneration and trauma.
Resources:
1. American Optometric Association. [www.aoa.org]
2. American Foundation for the Blind. [http://www.afb.org/section.aspx?sectionid=26&topicid=144 ]