Maya Williams
Legal blindness is a severe form of vision impairment that significantly affects daily life. While it does not always mean complete blindness, it limits a person’s ability to perform tasks like reading, driving, or recognizing faces.
This article will cover:
- What legal blindness is and how it differs from complete blindness
- Symptoms that indicate vision loss
- The most common causes of legal blindness
- How it is diagnosed and managed with assistive devices like low vision glasses for the blind
By understanding the causes and available support options, individuals with legal blindness can improve their quality of life and maintain independence.
What is Legal Blindness?
Legal blindness is a specific term used to describe a level of vision loss. When someone is legally blind, it means they have a visual acuity of 20/200 or worse in their better eye, even when they’re wearing glasses or contact lenses. To put it simply, this means that something a person with normal vision can see clearly from 200 feet away, a person who is legally blind would only be able to see from 20 feet away.
Another way to define legal blindness is by looking at the visual field. If a person’s visual field is 20 degrees or less, this also qualifies as legal blindness. In a practical sense, this means their peripheral vision is extremely limited, making it feel like they’re looking through a small tunnel.
Even though people who are legally blind might have some vision, it is usually not enough to carry out most daily activities without help. They often rely on visual aids, such as magnifiers, specialized glasses, or assistive technologies, to help them navigate and interact with the world around them. These aids play a crucial role in enhancing their remaining vision and improving their quality of life.
Legal Blindness vs Complete Blindness
Key Differences:
Feature | Legal Blindness | Complete Blindness |
Some level of vision | Yes | No |
Can perceive light and shapes | Yes | No |
Vision correction helps | No (limited improvement) | No |
Eligible for disability benefits | Yes | Yes |
Can use low vision glasses or aids | Yes | No |
Legal blindness allows for some sight, while complete blindness means a total loss of vision with no light perception.
Symptoms of Blindness
Symptoms can vary depending on the cause, but common signs of legal blindness include:
- Severely blurred vision even with corrective lenses
- Loss of peripheral vision (tunnel vision)
- Inability to recognize faces or read signs
- Difficulty adjusting to different lighting conditions
- Frequent need for brighter lighting when reading
- Seeing dark spots, flashes, or floating shapes
Diagnosis of Blindness
Eye specialists use several tests to determine whether someone is legally blind, including:
- Visual Acuity Test: Measures sharpness of vision using an eye chart.
- Visual Field Test: Assesses peripheral vision loss.
- Dilated Eye Exam: Checks for diseases affecting the retina and optic nerve.
- OCT Scan: Uses imaging technology to detect retinal conditions.
Now, let’s explore the top five causes of legal blindness in detail.
Top 5 Causes of Legal Blindness
1. Age-Related Macular Degeneration (AMD)
What is it?
AMD affects the macula, the part of the retina responsible for sharp central vision. It is the leading cause of vision loss in adults over 50.
Symptoms:
- Blurry or distorted central vision
- Difficulty recognizing faces
- Dark or empty spots in vision
Treatment & Management:
- Low vision glasses for the blind to enhance remaining vision
- Anti-VEGF injections to slow disease progression
- Nutritional supplements (AREDS2 formula) to support eye health
2. Glaucoma
What is it?
Glaucoma damages the optic nerve due to high eye pressure, leading to gradual vision loss.
Symptoms:
- Loss of peripheral vision (tunnel vision)
- Blurry vision and halos around lights
- Sudden eye pain or headache (in acute cases)
Treatment & Management:
- Prescription eye drops to lower eye pressure
- Laser therapy or surgery in advanced cases
- Assistive devices like low vision aids
3. Diabetic Retinopathy
What is it?
Diabetes can damage blood vessels in the retina, leading to bleeding, swelling, and scarring.
Symptoms:
- Dark spots or floating shapes in vision
- Blurry or fluctuating vision
- Sudden vision loss in advanced stages
Treatment & Management:
- Blood sugar control to prevent progression
- Laser treatment to seal leaking blood vessels
- Vitrectomy surgery for severe cases
4. Cataracts (Untreated Cases)
What is it?
A cataract is a clouding of the eye’s lens, leading to blurred vision. While treatable with surgery, untreated cataracts can cause legal blindness.
Symptoms:
- Cloudy or hazy vision
- Increased light sensitivity
- Difficulty seeing at night
Treatment & Management:
- Cataract surgery (restores vision in most cases)
- Prescription low vision glasses for better clarity
- Stronger lighting for reading and daily tasks
5. Retinitis Pigmentosa (RP)
What is it?
RP is a genetic disorder that causes progressive retinal damage, often leading to tunnel vision and night blindness.
Symptoms:
- Difficulty seeing in low light (night blindness)
- Loss of peripheral vision
- Gradual vision deterioration over time
Treatment & Management:
- No cure, but assistive devices help
- Vitamin A therapy may slow progression
- Mobility training for independent living
Legal blindness is caused by eye diseases like AMD, glaucoma, diabetic retinopathy, and retinitis pigmentosa. Early detection and proper management can slow progression and improve daily functioning.
With the help of low vision glasses for the blind, assistive technology, and medical treatments, individuals with legal blindness can continue to lead independent and fulfilling lives. If you or a loved one are experiencing vision loss, consult an eye specialist as soon as possible.
FAQs About Legal Blindness
1. Can legal blindness be cured?
Most causes of legal blindness are irreversible, but low vision aids, glasses, and adaptive technologies can help improve vision.
2. How do low vision glasses help legally blind individuals?
Low vision glasses magnify objects, improve contrast, and reduce glare, helping individuals with AMD, glaucoma, and diabetic retinopathy maintain independence.
3. Is legal blindness considered a disability?
Yes, individuals with legal blindness qualify for disability benefits and support programs, including mobility training and assistive devices.
4. Can people with legal blindness still see?
Yes, many people with legal blindness retain some level of vision, but it is severely impaired and requires assistive tools.
5. What are the best low vision aids for the blind?
The best aids include:
- Magnifying low vision glasses
- Screen readers and text-to-speech software
- Smartphone accessibility features
