What is Color Blindness? What are the Types of Color Blindness?

Color blindness is a vision defect that causes colors not to be seen correctly due to some cones (nerve cells) in the eyes being missing or not working properly. Individuals with this condition may have difficulty seeing the difference between certain colors or shades or perceiving the brightness of colors. Color blindness is usually an inherited disease. Male individuals are more likely to suffer from this condition than females.

Color blindness can occur in different types. These are as follows:

• Red-green color deficiency,
• Blue-yellow color deficiency,
• Complete color deficiency.

This inherited vision defect may also occur as a result of some eye diseases and various medications used. Going for routine eye checks can contribute to the prevention of vision defects. For this reason, it is very important to have regular eye examinations to prevent the formation of color blindness and other vision defects.

What is Color Blindness?

Some conditions that negatively affect eye health may cause different vision defects. Visual defects can negatively affect the quality of life in daily life. Color blindness (lack of color vision) is a vision defect in which colors are not seen as they are. This happens when the cones (a type of nerve cells in the eye retina) don't work properly. Cones in the eye send signals that enable the perception of the colors of light and images.

The majority of people with color blindness see some colors, while certain colors are not visible. sees differently than others.

Is Color Blindness Treatment Possible?

There is no medical treatment yet for individuals with inherited color blindness. However, in vision disorders that develop as a result of environmental factors, medication may be recommended by the doctor to treat the underlying condition. This treatment can help improve vision in different colors in the eye.

You may have heard of contact lenses and glasses specially produced for color blindness. Such tools can provide a richer color experience for people with mildly abnormal forms of trichromacy (defective vision). However, the use of glasses can increase the contrast between colors and help people with color blindness see the differences more clearly.

How to Test for Color Blindness?

Several different tests performed by an ophthalmologist can help diagnose color blindness. The Ishihara test is quite commonly used by ophthalmologists to diagnose red-green color blindness. Colored plates are shown by the doctor for the test. Each plate used contains patterns of small dots. Between these dots is a number (or a shape for young children) that can be seen by the healthy eye. However, based on the results of the Ishihara test, the doctor may recommend further testing to confirm the diagnosis or obtain more information.

Rod Monochromasia (Achromatopsia)

Achromatopsia is a vision defect that occurs when all or most of the cones are missing or do not work properly. In this case, all objects are seen in gray and its shades. However, other vision problems may also occur that may affect the quality of life.

Blue Cone Monochromaticity

This visual defect may occur rarely. As a result of blue cone monochromaticity, S cones may be active while L and M cones may not be active. Other eye problems such as light sensitivity (photophobia), nystagmus (a condition that causes the eyes to move quickly out of control) and nearsightedness may also occur as a result of difficulty distinguishing the differences between colors or seeing objects mostly in gray.

Blue-Yellow Color Deficiency

Blue-yellow color vision defects (tritan defects) are much less common than red-green color deficiency. Blue-yellow vision defects can occur in different ways. These are as follows:

• Tritanopia: In the case of tritanopia, which causes blue light not to be perceived correctly as a result of problems in the S cone, red, light blue, pink and magenta colors are mostly seen.
• Tritanomaly: In this case, although all three cone types are formed, S cones are less sensitive to blue light than they should be. In case of tritanomaly, the blue color may appear as green while little or no yellow may be visible.

Red-Green Color Deficiency

Red-green color deficiency is the most common type of color blindness. There are four main subtypes of this condition, which causes seeing colors or shades that have some red and green in them as other colors. These are as follows:

• Protanopia: In case of protanopia, where red light is not perceived correctly as a result of the lack of L cones, colors are mostly seen as blue or golden tones. Different shades of red can be easily confused with the color black.
• Deuteranopia: Deuteranopia, which occurs when M cones are missing, causes green light not to be perceived correctly. Deuteranopia can cause some shades of red to be confused with shades of green. However, yellow color and bright shades of green may not be distinguishable.
• Protanomaly: In this case, where all three cone types are present, L cones may be less sensitive to red light than they should be. The red color may appear as dark gray.
• Deuteranomaly: Individuals with this condition are sensitive to all three cone types.

What are the Types of Color Blindness?

Cones are nerve cells in your eye that detect colors in the visible light spectrum. This spectrum includes all wavelengths that humans can see. The spectrum range can vary from 380 nanometers (short) to 700 nanometers (long). A healthy individual has three types of cones:

• Red-Detecting Cones (L cones): These cones detect long wavelengths (about 560 nanometers).
• Green-Detecting Cones (M). cones): Green-sensing cones detect medium wavelengths (about 530 nanometers).
• Blue-sensing cones (S cones): Blue-sensing cones, also known as S cones, detect short wavelengths (about 420 nanometers).< /li>

Various types of color blindness may occur depending on the functioning of the cones in the eye. Some of these are as follows:

What Causes Color Blindness?

Changes (mutation) in genes can cause hereditary color blindness. However, blue-yellow color deficiency can often develop later. Non-congenital color vision defects may occur as a result of different environmental causes. Some of the conditions that cause color blindness are as follows:

• Genetic factors,
• Exposure to chemicals that damage the nervous system, such as heavy metals,
• Some diseases, including hydroxychloroquine use of medications (for the treatment of rheumatoid arthritis),
• Eye conditions such as age-related macular degeneration (macular degeneration), glaucoma and cataracts,
• Diabetes, Alzheimer's disease and multiple sclerosis (MS). Some medical conditions that affect the brain or nervous system, including:
• Prolonged exposure to source lights,
• Retinal detachment (a condition that occurs when the retina pulls away from its normal position),
• Eye injuries caused by lasers,
• Some brain tumors (especially those that affect the optic nerve or put pressure on the brain),
• Radiation treatments.

What are the symptoms of color blindness?

Symptoms resulting from color blindness may not be noticed by individuals. Some of the symptoms that occur as a result of this situation are as follows:

• Having difficulty distinguishing different shades of red and green,
• Having difficulty distinguishing different shades of blue and yellow,
< li>Not being able to see any color correctly.

Many people with color blindness may not be able to distinguish the differences because they always see colors the same way. For this reason, color blindness may not be detected early.

Source

https://my.clevelandclinic.org/health/diseases/11604-color-blindness

https://www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/ color-blindness#:~:text=What%20is%20color%20blindness%3F,vision%20deficiency%20runs%20in%20families.

https://www.mayoclinic.org/diseases-conditions/poor-color-vision/symptoms-causes/syc- 20354988