Heterochromia iridis or heterochromia is a condition wherein a person has eyes with different colors. Typically, it does not cause any problems and is usually an oddity passed by something that happened during one’s eye formation or via the genes. In some rare cases, it can be a symptom of an underlying medical condition. It is prevalent in animals but is a rarity in humans. In the country, less than 200,000 people are affected by it.

Types of heterochromia iridis
Heterochromia shows a difference in eye colors. However, if it is caused by an underlying condition, it can lead to a few other symptoms. Further, one can notice a difference in how eye colors vary. Hence, heterochromia Iridis is classified into three main categories:

Complete heterochromia: Here, one iris color is entirely different from the other. For instance, the iris in one eye is brown, whereas that in the other is green.

Segmented or partial heterochromia: Here, the color of the part of one iris varies from that of the color of the rest of the same iris.

Central heterochromia: The iris ring in the iris varies from the remaining parts of the same iris. Some people may even classify them by the color difference between the two eyes.

Symptoms
The symptoms of heterochromia may vary depending on the type. However, some common symptoms of the condition are:
Patches of different colors in one eye
Rings of color around the pupil
Two different colored eyes

Causes
Sometimes babies have congenital heterochromia iridis, meaning they are born with it, or it begins shortly after birth. Usually, this will not cause any other visual problems. However, some infants may get it as an outcome of another disease. Thus genetics can be one of the causes of heterochromia iridis . Some conditions that may lead to heterochromia Iridis are:

Bourneville disease
Hirschsprung disease
Horner’s syndrome
Parry-Romberg syndrome
Sturge-Weber syndrome
Von Recklinghausen disease
Piebaldism
Waardenburg syndrome
Bloch-Sulzberger syndrome
Benign heterochromia

Some people may also develop heterochromia later in life. In these cases, it is called acquired heterochromia. It is usually caused by a disease or an injury. Other conditions that may lead to heterochromia are:

Iritis or uveitis
These conditions inflict swelling and can cause a change in eye color. It causes inflammation in the uvea. Iritis refers to an inflamed iris.

Glaucoma
Heterochromia can be caused by glaucoma and its treatment options. Glaucoma is characterized by increased pressure in the eye and can result in blindness if not treated immediately.

Iris tumors
Tumors may also develop in the iris. While some are malignant, others may be benign. Melanoma is one of the common tumors that cause heterochromia.

Fuchs’ heterochromic cyclitis
It is an inflammatory syndrome affecting the uvea. The precise cause is unknown, but rubella, toxoplasmosis, and herpes simplex can lead to this disease.

Diabetes mellitus
Diabetes mellitus causes a surge in blood sugar levels. Some of the prevalent symptoms of diabetes include issues with the eyes, especially if the blood sugar levels remain elevated for a long time.

Acquired Horner’s syndrome
It occurs later in life, leading to facial anhidrosis, eyelid ptosis, and miosis. Usually, it affects only one side of the face.

Pigment dispersion syndrome
It is a condition resulting in pigmentary glaucoma. It is characterized by the pigment cells in the iris shedding off the back. After sloping off, they begin floating around the fluid in the eye.

Injury
An eye injury may also change the color of one’s eye. It is usually an outcome of trauma when someone undergoes eye surgery. Bleeding in the eye after an injury may also change the iris color.

Treatment
Usually, heterochromia iridis is a harmless condition that needs no treatment. However, one may need treatment if a healthcare expert determines that heterochromia iridis is because of an illness or an underlying condition. It is best to consult a doctor about any queries or doubts that one may have and form an accurate treatment plan if needed. However, if one is bothered by the different colors in the eye, one can try colored contact lenses. But it makes one unique and should not be bothered if it is not causing any symptoms.