heterochromic uveitis
Last reviewed 01/2018
This is an idiopathic form of anterior uveitis which accounts for about 3% of all cases. It is essentially a cyclitis with depigmentation of the iris in the affected eye. It develops insidiously and typically affects young adults in the third or fourth decade.
Characteristically, the patient presents with slight clouding of vision and floating spots in one eye. There is no redness, pain or photophobia. The irises are different colours but this may not be noticeable early on or when the normal colour of the iris is grey or blue.
On examination, translucent, non-pigmented keratic precipitates may be seen on the posterior corneal surface. Fine particles or cells may be seen in the anterior chamber. The iris shows stromal atrophy and when transilluminated through the pupil, the pigment epithelium is seen to have a moth-eaten appearance at the pupillary margin. Posterior synechiae are rare.
Cataract develops within a few years in 15% of cases, and secondary glaucoma in 10-15% of cases. There may be a slight ptosis and enophthalmos on the affected side.
Anti-inflammatory treatment with steroids is ineffective. The visual prognosis is usually good since the cataract can often be removed safely despite the low-grade active uveitis.