What is Heterochromia? Why Does It Happen?

Heterochromia is a color change that usually occurs in the eyes. It can also appear on the skin and hair. Normally, individuals have the same color in both eyes, but people with heterochromia see different colors in their eyes. Heterochromia, which is rare in humans, can be seen more commonly in cats, dogs and horses. This condition may be congenital or may occur immediately after birth. Although heterochromia is mostly harmless, in rare cases it can be a symptom of a medical condition. Contrary to popular belief, this condition is not a disease and does not cause any changes in vision. There are two types: complete heterochromia and partial heterochromia. Because heterochromia is a genetic condition, it can be inherited from a syndrome or an inherited disease. However, there may be more than one reason for this situation.

Heterochromia is generally an aesthetic condition and can be visually interesting. While some people accept heterochromia as their uniqueness, others may feel uncomfortable with the condition. You can take a look at the rest of the article to learn other details about heterochromia.

What is Heterochromia?

Heterochromia is usually seen in the iris, but can sometimes be seen in the hair and skin. This word, meaning different colors, comes from Greek. Since hetero means different in Greek and chroma means color, heterochromia means color difference. Since heterochromia is a term generally used for color changes in the body, the expression heterochromia "iridium" or "heterochromia iridis" is used to express the color change in the eyes. Although heterochromia, which causes color change in the iris that gives color to the eye, is generally considered a genetic feature, it can also develop due to reasons such as trauma and there are many different types. The difference between the colors of the irises can sometimes occur with the distribution of completely different colors, and sometimes with two different eye color tones in the iris of one eye.

This means that one eye may be brown or black, while the other may be blue, green or gray.

Heterochromia is generally considered an aesthetic feature and attracts the attention of many people. However, in some cases, heterochromia may be a symptom of some eye conditions or may be associated with some genetic syndromes. Heterochromia iridium usually does not have any effect on vision and does not require treatment. However, it is important to consult an ophthalmologist if the color difference occurs suddenly or is accompanied by eye pain, vision loss or other symptoms.

What Causes Heterochromia?

Heterochromia is the result of excess or deficiency of melanin pigment. The reason for this difference in distribution is benign mutations occurring in autosomal chromosomes. However, there may be more than one reason for this situation. Primary heterochromia is generally considered a genetic trait. In other words, if one of the person's parents or family members has heterochromia, this feature can be transferred to another person. Genetic mutations and genetic syndromes can also cause heterochromia.

Secondary heterochromia may occur due to reasons such as trauma or as a symptom of another health problem or condition. Eye infections, eye injuries, eye surgeries, eye tumors, inflammatory conditions or some systemic diseases can cause heterochromia. In addition, long-term use of some medications or eye drops can also cause heterochromia.

Heterochromia can also be associated with some genetic syndromes, conditions that cause congenital heterochromia can be listed as follows:

• Waardenburg Syndrome:Waardenburg syndrome is a rare genetic syndrome characterized by a number of disorders related to pigmentation. This syndrome may be associated with symptoms such as heterochromia, changes in hair color (e.g. white headbands), hearing loss, and ear shape abnormalities.
• Horner Syndrome:Horner syndrome is due to sympathetic nervous system problems. It is a situation that occurs. In this syndrome, lack or reduction of pigmentation in the iris of one eye can cause heterochromia.
• Sturge-Weber Syndrome:Sturge-Weber syndrome is a congenital disorder in which abnormal blood vessels are found in the brain and face. This syndrome can sometimes lead to heterochromia, with color changes in the iris of one eye, especially being darker in one half.
• Hirschsprung's Disease:This disease, which affects the large intestines, can cause heterochromia in babies. li>
• Phakomatoses: Rare genetic diseases such as tuberous sclerosis, neurofibromatosis and some other phakomatoses may be associated with heterochromia.

Types of Heterochromia?

Different types of heterochromia can affect different parts of an individual's eye. Types of heterochromia can be listed as follows:

1. Partial Heterochromia:In this type of heterochromia, color change occurs in the iris of one eye, while there is a single color in the iris of the other eye. For example, although one eye is blue, the other eye is brown.
2. Sectoral Heterochromia:In sectoral heterochromia, there are different color areas in the iris of one eye. For example, while most of one eye is blue, the other part may be brown or green.
3. Complete Heterochromia:In this type of heterochromia, the irises of both eyes have completely different colors. For example, one eye is a blue eye and the other eye is brown.
4. Central Heterochromia:Central heterochromia occurs when rings of different colors form in the eye. In this case, the periphery of the irises usually has a different color, while the central parts of the iris may have a different color. For example, while the outer part of the eye is blue, green or brown, the inner part may be a different color.

Heterochromia types may vary from individual to individual and may differ in each case. The colors of the eyes are determined depending on the amount and distribution of melanin in the irises.

Is Heterochromia a Disease?

Heterochromia is not a disease, but a natural variation. Color difference in the eyes is usually caused by genetics or congenital diseases. Heterochromia, which is generally harmless, does not have any effect on eye health. However, in some cases, heterochromia may be associated with other eye problems. If you are concerned about heterochromia, it is important to consult an ophthalmologist.

How to Diagnose Heterochromia?

Heterochromia is usually diagnosed by an ophthalmologist. The following steps can be followed to diagnose heterochromia:

1. Eye Examination:An ophthalmologist examines your eyes in detail. During this examination, he examines the color differences in the irises of your eyes.
2. Inquiry about Medical History:The doctor may question your medical history about conditions such as genetic factors, trauma, infections or medications that may cause heterochromia. This can help identify potential causes that may lead to heterochromia.
3. Intraocular Pressure Measurement:The doctor may measure your intraocular pressure. Some eye diseases can be diagnosed with this test.
4. Vision Tests: When necessary, the doctor may perform vision tests to evaluate the visual ability of your eyes.

This These steps are generally followed in diagnosing heterochromia. Note that your doctor may use certain methods to diagnose heterochromia. If you show symptoms of heterochromia, it is important to consult an ophthalmologist.

How is Heterochromia Treated?

Heterochromia usually does not require treatment. Because this condition is generally harmless and does not affect eye health. Many people with heterochromia live normally and do not need any treatment. However, if there is another eye problem or disease causing heterochromia, the underlying cause may need to be treated.

Heterochromia may be a cosmetic concern, and some people may use colored contact lenses to correct heterochromia or reduce color difference. These lenses can equalize or change the color tone of the eyes. However, the use of contact lenses is a matter of personal preference and is not a medical treatment.

If you have symptoms of heterochromia, you can consult a healthcare provider for diagnosis of this condition or to get more comprehensive information about this subject.

Source

https://www.webmd.com/eye-health/heterochromia-iridis

https://www.ncbi.nlm.nih.gov/books/NBK574499/

https://www.verywellhealth.com/heterochromia-overview-4177928

https://www.healthline.com/health/central-heterochromia

https://www.medicalnewstoday.com/articles/319389