Causes, Types and Diagnosis of Heterochromia

Heterochromia is a condition that affects the coloring or pigmentation of the eyes, skin or hair. The Iris is a part of the human eye that forms the color of the eyes. Heterochromia Iridis is a condition in which the eye has multiple pigmentations. Heterochromia Iridis is a rare condition.

Types of Heterochromia:

1. Complete Heterochromia: Here, the Iris of both eyes has two different colors i.e the Iris of the left eye is green and the right is blue.

2. Central Heterochromia:
People with central heterochromia have different colors near the border of their pupils.

3. Segmental Heterochromia:
This condition is almost like that of the complete heterochromia. It occurs when a patch of color appears in one iris. In some cases It can occur in both eyes.

Causes of Heterochromia

You might be wondering what causes this coloring in the eyes, well just like the skin, melanin is responsible for the coloring of the eyes. When the eyes lack melanin the iris takes a different color, but when there is melanin the iris takes the color brown. The brown coloring of the eyes shows that the eyes do not lack melanin.

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Here are some of the causes of the coloring of the Eyes:

Heterochromia Iridis

Heterochromia may be congenital (genetic) or acquired.

1. Congenital (genetic) Heterochromia:

Congenital heterochromia is a type of heterochromia that is gotten from birth or developed soon after birth. It is hereditary and does not have any negative effect or show any sign of abnormality on the eyes.

2. Acquired Heterochromia:

This is caused by injuries or trauma in the eyes, it has negative effects on the eyes. Examples of acquired heterochromia includes the following: Waardenburg Syndrome, Horner’s Syndrome, Party-Romberg Syndrome, Sturge-Weber Syndrome etc.

Causes of Heterochromia in Infants:

1. Benign Heterochromia:

This occurs in infants without showing any sign of abnormality. It occurs in people without a family history.

2. Horner’s Syndrome:

Horner’s syndrome is as a result of another medical condition, it is caused by a disruptive nerve pathway on one side from the brain to the face and then the eyes. Medical conditions like stroke, tumor, or spinal cord injury causes horner’s syndrome.

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3. Sturge-Weber Syndrome:

Sturge- Weber Syndrome also known as “encephalotrigeminal angiomatosis” is a neurological disorder that marked by a distinctive port-wine stain on the forehead, scalp or around the eyes.

4. Waardenburg Syndrome:

Waardenburg Syndrome is a rare genetic condition that is characterized by some degree of congenital hearing loss and pigmentation deficiencies.

5. Piebaldism:

Piebaldism is a genetic condition that is gotten at birth. Piebaldism causes a person to develops unpigmented or white patches of skin or hair. In piebaldism the cells that are responsible for the coloring of the eye, skin and hair color are absent.

6. Hirschsprung Disease:

Hirschsprung Disease is a condition that makes someone experience difficulty in stooling, it is caused by the missing nerve cells in the muscle of part or all of the large intestine.

7. Bloch-Sulzberger Syndrome:

Bloch-Sulzberger Syndrome also known as Incontinentia Pigmenti (IP), is a genetic disease that develops after birth in areas such as the trunk and limbs, it heals, but leaves dark streaks and marble-like whorls on the skin.

8. Von recklinghausen Disease:

Von recklinghausen Disease also called Neurofibromatosis 1 (NF 1) is a genetic disorder characterized by the development of multiple non-cancerous tumors on the nerves and skin.

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9. Bourneville Disease:

Bourneville Disease also known as Tuberous Sclerosis ( TS) or Bourneville Pringle Disease (BPD) is a type of disease with dormant auto-somal inheritance. It is one of the major causes of heterochromia.

10. Party-Romberg Syndrome:

Party-Romberg Syndrome is known as a rare disorder that is characterized by the deterioration of the skin and soft tissues of half of the face. Party-Romberg Syndrome usually affects the left side of the face.

Heterochromia Iridis

Risk Factors / Side Effects of Acquired Heterochromia:

1. Glaucoma
2. Swelling of the eyes
3. Eye surgery
4. Fuch’s Heterochromic Cyclitis
5. Eye injury
6. Bleeding in the eyes
7. Tumors of the iris


Whenever you notice a change in the color of your eyes endeavor to see an opthalmologist. Opthalmologists will examine your eyes to confirm if there is really a change in the color of your iris, then proceed into looking out for possible signs of diseases that has caused the change. Heterochromia is diagnosed using a slit lamp examination.