Types of Blindness: What to Know

Medically Reviewed By Ann Marie Griff, O.D.

The types of blindness vary based on severity and how exactly vision is affected, such as whether you have partial or total blindness. Doctors may categorize blindness types based on how much vision you have, how exactly your vision is impaired, and its cause.

Talk with an eye doctor if you have any questions about your vision and blindness.

This article discusses the primary types of blindness, how they affect your vision, and common causes of blindness.

The main types of blindness

A blurry image of orange and white flowers in a field.
Deirdre Malfatto/Stocksy United

Healthcare professionals classify the types of blindness into various categories.

Total blindness

Total blindness is the most severe form of blindness.

It refers to a complete lack of light perception and shape recognition, meaning you cannot see anything.

Total blindness makes up about 15% Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source of eye disorders.

Partial blindness

Low vision or partial blindness describes Trusted Source National Eye Institute Governmental authority Go to source significantly reduced vision that cannot be solved with eyeglasses, contact lenses, or medical treatments like surgery.

Partially blind people still have some vision. For example, some may be able to see shapes, outlines, and lights or changes in light.

However, the type and severity of partial vision loss can vary widely.

Partial blindness can present as:

  • blurry or hazy vision
  • night blindness, or difficulty seeing in low light
  • central vision loss, whereby you can see in your peripheral or side vision but not straight ahead
  • peripheral vision loss, whereby you can see in your central vision but not your peripheral vision

Partial blindness can also affect your ability to do daily tasks, such as driving or reading.

Read more about what blind people can see and support for low vision.

Legal or statutory blindness

The Social Security Administration (SSA) considers you to have legal or statutory blindness if you have either of the following features in your best eye:

  • a visual field with an angle of 20 degrees or less
  • a visual acuity of 20/200 or less when using corrective aids like glasses or contact lenses

The U.S. government uses this classification to determine a person’s eligibility for government disability benefits and assistance. 

It’s possible to meet the SSA’s definition and still have some remaining vision, as long as it’s less than the amounts outlined above. As a result, legal blindness can include people with partial or total blindness.

Visual impairment

“Visual impairment” is a general term that refers to any form of reduced vision or vision problem. It includes partial and total blindness as well as:

  • refractive errors, such as nearsightedness or shortsightedness
  • problems with visual acuity, or how well you can see at a certain distance
  • problems with visual field, or how wide your peripheral vision is
  • other vision symptoms due to eye conditions, such as straight lines looking bent due to age-related macular degeneration (AMD)

Colorblindness

Colorblindness refers to seeing colors differently from most other people, such as difficulties with:

  • identifying a color or shade correctly
  • spotting the difference between colors
  • seeing how bright colors are

Most colorblind people have the condition from birth. However, injury to the eye’s retina, the optic nerve, or the brain can also lead to colorblindness. The retina is a layer of light-sensitive cells that sends visual information through the optic nerve to the brain to produce vision.

According to the National Institutes of Health (NIH) Trusted Source National Eye Institute Governmental authority Go to source , most cases of colorblindness are mild and do not affect daily activities. However, other cases can be severe and occur alongside other visual symptoms, such as light sensitivity.

Read more about colorblindness, including its symptoms and treatment.

Night blindness

Night blindness, or nyctalopia, occurs when the retina cannot adapt to light changes well, making it more difficult to see in low light.

Various eye conditions can cause Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source night blindness, including vitamin A deficiency and retinitis pigmentosa.  

Learn more about night blindness and its symptoms, causes, and treatment.

Blindness types by cause

Healthcare professionals may also categorize types of blindness according to their cause.

Age-related blindness

Age-related blindness results from various eye conditions that commonly develop or progress with age, such as Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source :

  • Age-related macular degeneration (AMD): age-related damage causes central vision loss
  • Glaucoma: a condition that damages the optic nerve
  • Cataracts: a clouding of the eye’s lens

Not everyone with eye conditions will become blind. However, eye conditions may eventually lead to permanent vision loss if you do not receive timely or effective treatment.

Getting regular eye checkups can help you get early treatment, which may help protect your vision.

Regular eye exams throughout life can help prevent blindness

Many eye conditions do not cause noticeable symptoms at first. Sometimes, only an eye doctor can spot signs of an eye problem before it causes permanent damage.

Talk with an eye doctor about how often you should get a comprehensive eye exam, as this may vary from person to person.

Get medical help immediately for any sudden, severe, or concerning vision symptoms.

Genetic and congenital blindness

For some people, genetic conditions cause blindness from birth, known as congenital blindness. Others have a genetic condition from birth but may not start to experience symptoms or vision loss until later in life.

Genetic conditions that can lead to blindness include:

Injury

Eye injuries can lead to vision loss and blindness by damaging the eye’s structure or function. Injuries often occur from:

  • burns and chemical splashes
  • UV light
  • sharp objects in the eye
  • blunt trauma to the eye, such as from a punch or elastic cord
  • flying objects, such as balls or flying debris from explosions

Get immediate medical help if you experience an eye injury, even if you do not have any vision problems.

Infections 

Viruses, fungi, and bacteria can cause eye infections and damage vision.

For example, a bacterial infection called trachoma is the leading infectious cause Trusted Source World Health Organization Highly respected international organization Go to source of blindness worldwide.

Trachoma can infect the eye repeatedly and lead to scarring if not treated in time. This scarring may cause the eyelashes to turn inward, scratching the cornea and possibly causing blindness.   

Other health conditions

Other health conditions may lead to blindness as a complication or secondary effect:

Nutritional deficiencies

Sometimes, severe nutritional deficiencies can lead to vision impairments.

For example, vitamin A deficiency can increase your risk of night blindness and other vision problems.

In fact, the American Academy of Ophthalmology suggests that vitamin A deficiency is the primary cause of preventable blindness in children across the world.

Snow blindness

Snow blindness is a temporary visual impairment caused by exposure to bright, reflected sunlight, often from snow.

The sun’s UV rays can cause photokeratitis, or a sunburned cornea, causing symptoms like:

Wearing protective eyewear, such as sunglasses that block UV rays, can help prevent snow blindness. 

Learn more about vision loss, including its types, management, and outlook.

Summary

The types of blindness differ based on how much they affect vision. Total blindness refers to not being able to see anything. Partial blindness refers to some vision loss but still being able to see some things.

Some people also categorize blindness based on its cause or other features of its development. For example, some people experience congenital blindness, which is blindness from birth.

Talk with an eye doctor if you have any questions about blindness or vision impairment.

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Medical Reviewer: Ann Marie Griff, O.D.
Last Review Date: 2024 Jun 26
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.