Color blindness is the difficulty in telling the difference between certain colors or shades. Very rarely color blindness makes a person unable to see any colors.
Color blindness is mostly an inherited genetic condition. In some cases, it can be acquired in life due to the side effects of certain medications, industrial and environmental chemicals, or chronic illnesses.
Individuals with color blindness encounter some common difficulties in day-to-day life like choosing fresh vegetables, fruits, and flowers, driving a car, and selecting clothes.
Currently, there is no treatment for this condition. However, specific photographic frames eyeglasses and contact lenses can be used to improve the distinguish between some colors.
Screening tests
The symptoms of color blindness vary from person to person. Many people have such mild symptoms that they don’t even realize they have color blindness. The symptoms of color blindness may include:
The retina (the light-sensitive layer at the back of the eyeball) of the eyes has two types of photoreceptor cells. They are called the rods and the cones. The rods detect lightness and darkness whereas the cones detect colors. There are three types of cones that are able to interpret the primary colors ie. red, green, and blue:
Red-sensing cones (L cones): These cones perceive long wavelengths of light (around 560 nanometers).
Green-sensing cones (M cones): These cones perceive middle wavelengths (around 530 nanometers).
Blue-sensing cones (S cones): These cones perceive short wavelengths (around 420 nanometers).
These cone cells send information through the optic nerve to the brain. The brain then uses this input to determine our color perception.
Color blindness can occur when one or more types of cone cells are absent, not working properly, or detect a different color than normal. Mild color blindness happens when one cone cell does not work right. Severe color blindness occurs when all three cone cells are absent or defective.
The different types of color blindness are:
This is the most common color blindness that makes it hard for the individual to differentiate between red and green.
There are 4 types of red-green color blindness:
This is a less common type of color blindness in which an individual is unable to differentiate between blue and green, and between yellow and red.
There are 2 types of blue-yellow color blindness:
This is the rarest form of color blindness. In this type of color blindness, there is a lack of working L cones or M cones. There are only S cones. Individuals having this kind of color blindness often find it hard to tell the difference between colors and see mostly grays.
Achromatopsia is a condition when all or most of the cones are missing or not working properly. This is also called monochromacy, and it’s quite rare. For them, their world consists of different shades of gray ranging from black to white, rather like seeing the world on an old black-and-white television set. An individual may also have other vision issues that may greatly impact their quality of life.
The various risk factors of color blindness can be inherited (a person is born with it) or acquired (developed later in life). The causes are different in each case.
Inherited color blindness
Most people with color blindness are born with it. This is called a congenital condition. A change (mutation) to the genes leads to inherited color blindness. The most common form, red-green color blindness, follows an X-linked recessive inheritance pattern. The genetics for red-green color blindness are:
In males
A male baby will have red-green color blindness if the mother has the condition
There is a 50% chance of inheriting red-green color blindness if the mother is a carrier (the mother carries one copy of the genetic mutation but doesn’t have the condition). The other copy is normal, hence there is a 50% chance.
The condition would not be present if the father has the condition as the father contributes the Y chromosome to male babies and the X chromosome to female babies.
In females
A female baby will inherit red-green color blindness if both parents have the condition.
The female baby would be a carrier in case the father has the condition but the mother does not.
There will be a 50 percent chance of inheritance of red-green color blindness (50% chance) or a carrier (50% chance) if the father has the condition and the mother is a carrier.
Acquired color blindness
This color blindness mostly develops as a blue-yellow color deficiency, and has many associated risk factors including
Aging: The ability to distinguish different colors deteriorates slowly with age.
Chronic illnesses: Having eye-related diseases such as age-related macular degeneration or glaucoma increases the likelihood of color blindness. Having health issues like diabetes, multiple sclerosis, Alzheimer’s disease, autoimmune diseases, high blood pressure, heart problems, nervous disorders, and physiological issues multiplies the chances of color blindness.
Stroke: Accidents or strokes that damage the retina or affect a particular area of the brain or eye can lead to color blindness.
Medications: Certain medications for high blood pressure, diabetes, hypertension, erectile dysfunction, tuberculosis, and specific antibiotics and barbiturates, can alter the vision of the eyes.
Industrial and environmental chemicals: Exposure to chemicals such as carbon monoxide, carbon disulfide, organic solvents, and some containing lead may also increase the risk of color blindness.
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Accurately diagnosing color blindness is important to reduce further complications. Diagnosis includes
A complete history provides important information to determine whether the patient has a family history or is having certain diseases and taking certain medications.
The tests for color vision deficiency are:
Ishihara test: This is the most well-known test for color blindness. A set of images called the Ishihara color plates is used for the detection of color blindness. The individual is told to look at the images, which have numbers embedded in dots of color. The color of the numbers is a different color than the background. If the person cannot see the numbers, then the individual is probably colorblind.
Lantern tests: This test is also called a Farnsworth Lantern [FALANT] test which is used for detecting individuals that are unable to distinguish between red and green. During this test color pairs (including red, green, and white) are shown and the outcome is based on the number of color-naming errors.
Anomaloscope: A simple instrument anomaloscope is used to diagnose color blindness. In this test, two different light sources have to be matched to the same color. They are optical instruments in which the observer must manipulate stimulus control knobs to match two colored fields in color and brightness. This is a standard instrument for the diagnosis of color vision defects.
Color arrangement tests: This test is also called the hue test. The doctor will provide you with blocks that are different colors. The doctor will ask you to arrange them in rainbow order, from red to purple. If the individual is facing trouble putting them in the correct order, there are chances of having a type of color blindness.
There is no way to prevent color blindness that has been present since birth. But there are chances to reduce the occurrence of color blindness later in life by getting regular eye examinations and steering clear of avoidable risk factors.
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You should contact your doctor immediately if you have the following symptoms:
Doctors that can help you diagnose and treat color blindness include:
An ophthalmologist or an optometrist is a medical practitioner who specializes in eye and vision care. The doctor helps detect any problems related to eyes and vision early.
If you or your loved ones are noticing any of the above symptoms, seek medical help from our trusted team of doctors.
Currently, there is no cure for color blindness that is present from birth (inherited color blindness). In many cases, most people with color blindness learn to adapt and live with the same condition.
If color blindness is happening because of another health problem (acquired color blindness), the doctor will treat the condition causing the problem. If someone is taking a medicine that causes color blindness, your doctor may suggest altering the ratio if required or switching to a different medicine.
Here are some ways to work around poor color vision:
Special glasses or contacts may also help some people with red-green deficiency see the difference between colors.
These glasses were created for doctors to use during laser surgery procedures. They were originally created as sunglasses with lenses coated in a special material that exaggerated the wavelengths of light.
It was discovered that the coating on these lenses might help people with poor color vision to see the differences in pigment but to varying extents.
These glasses work by filtering out certain wavelengths of light to help people better distinguish red and green colors. The glasses do not help in restoring normal color vision, but they may make certain hues appear more vibrant.
These glasses are now used as color-correcting glasses designed to alleviate symptoms of red–green color blindness. But the options are highly limited and expensive to be used by all individuals.
Contact lenses for color blindness are the most common choice for many patients, as it is easy to use and painless too.
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Certain apps can be used to take a photo with the phone and then tap on the part of the photo to find out the color of that area.
Research has been going on gene therapy (a technique that uses genes to treat, prevent or cure a disease or medical disorder) for people who have inherited color blindness. If modern gene therapy does catch on, treatments for color blindness may eventually be approved and could open the door to color vision enhancement.
Potential gene replacement therapy for red-green color blindness has already been tested in animals.
Individuals with a severe form of color blindness can face complications like:
Achromatopsia: It is a condition characterized by the partial or total absence of color vision. The individual cannot perceive colors except black, white, and shades of gray.
Nystagmus: It is a condition in which your eyes make rapid, repetitive, uncontrolled movements. In some cases of color blindness, individuals may face involuntary back-and-forth eye movements.
Photophobia: The discomfort in bright light can be due to color blindness.
If color blindness occurs as a result of illness or injury, treating the underlying cause may help to improve color blindness. However, there’s no cure for inherited color blindness.
People with color blindness often consciously apply certain techniques or use specific tools to make life easier by
A few tips that can help in managing everyday challenges:
1. Aim for right lighting
Lighting makes a big difference in the abilities of those with a vision deficiency. Yellow or dull lighting can make it even harder to perceive color. Glares can make it difficult to perceive colors properly. In areas where the lighting can be controlled, aim for bright, and natural light.
2. Use of smartphones and apps
With the help of advancements in technology, smartphone apps can assist people with color vision deficiencies in identifying colors. Certain apps are very useful while shopping or picking out clothes in the morning. The app is mainly designed for color-blind individuals and helps in
3. Look for Color Blind glasses
This is not a cure for color blindness. However, colorblind glasses are the best option. These glasses are just like the normal glasses available in multiple shapes and colors. These glasses work by filtering out the overlapping wavelengths that result in color blindness and help in seeing the world as a normal-sighted person and conquering everyday tasks.
4. Handling challenges in school
If the child is colorblind coordinate with teachers and ask the following points to help their children:
5. Shopping for fruits and vegetables
Suppose you find difficulties in distinguishing between fruits and vegetables due to color. In that case, you can search online or ask a worker at your grocery store for help in determining your favorite fruits and vegetables.
6. Cooking tips
For color-deficient individuals, it is difficult to determine if the food is fully cooked and ready to eat and if fruits and vegetables are ripe or rotten. The best practice to follow is while cooking, always follow temperature guidelines. Instead of determining if a piece of chicken has been cooked thoroughly based on the center of the meat's color, use a meat thermometer.
7. Addressing work challenges
Reading and designing PowerPoints at work, or working on graphs and images and reading company documents may possess a challenge. A color-blind employee can speak with the boss about ways the company can be more inclusive, such as changing company document templates to colors that aren't as difficult to comprehend.
8. Dealing with gadgets
Most advanced electronics these days have ways to signal a low or full battery without relying on color. For example, Apple computers have a setting called “Differentiate without colors.” Android phones also offer a higher version that offers color correction based on what colors the user is not able to see.
9. Reading traffic lights
For reading the traffic lights a color-blind person needs to rely on the position rather than the color. For traffic lights that run from top to bottom: the top stops, the middle is caution, and the bottom is gone.
There should be a simple tweak in the traffic lights to make color-deficient individuals perceive the light easier:
