What causes heterochromia iridum

Iris heterochromia

Synonym: Heterochromia iridium, Heterochromia iridis

1 definition

As Iris heterochromia This is the name given to the uneven coloration and structure of the iris of both eyes, which is caused by impaired pigmentation of the iris. As a result, those affected have two different eye colors.

2 etiopathogenesis

The cause of iris heterochromia is a unilateral partial or total iris pigment disorder. This can have different causes:

The difference in color in the eyes can also be caused by a sympathetic disorder. With sympathetic denervation, the iris pigmentation is absent and consequently leads to a lighter iris on the affected side. Depigmented areas appear as blue eyes.

The heterochromia is still associated with the Horner symptom complex (miosis, ptosis, enophthalmos) or a status dysrhaphicus.

3 forms

A distinction is made between the following forms of heterochromia:

  • Heterochromia simplex: The simple heterochromia is often associated with only a slight color difference in the eyes. Pathological changes such as visual disturbances do not occur.
  • Heterochromia complicata (fox): This form is usually only fully developed in adulthood. It is associated with recurrent iridocyclitis and precipitates on the posterior surface of the cornea (without posterior synechiae).
  • Heterochromia sympathica: If the sympathetic innervation is unilateral, the affected iris becomes increasingly lighter.
  • Melanosis iridis: Darkening of an iris

4 clinic

As a rule, the difference in color between the eyes is harmless and does not impair vision.

The only form that leads to pathological changes is Fuchs uveitis syndrome (Fuchs heterochromic cyclitis), a combination of heterochromia and chronic unilateral iritis. Clinically, the syndrome manifests itself in an externally irritation-free eye, an iris that is light on one side (heterochromia), the lack of adhesions between the iris and the lens and possibly an increase in intraocular pressure (secondary glaucoma).

5 complications

Heterochromia can be associated with recurrent iridocyclitis and cataracts (cataracta complicata).

6 therapy

No causal therapy for heterochromia is possible. Treatment with glucocorticoids is possible in the event of symptoms.

7 literature

  • Gerhard K. Lang: Ophthalmology. 5th edition. 2011. Thieme Verlag.