The uvea lies between the whites of the eye or the sclera and the retina. The uvea is supplied richly by blood vessels and is deeply pigmented. The choroid layer (choroid plexus, ciliary body and iris together) is also termed as uveal tract.
The term uveitis refers to inflammation at any point of the uveal tract with or without inflammation of neighbouring structures like the retina at the back of the eye or the vitreous humor or the liquid that fills the inner part of the eye ball.
There are several types of classifications of uveitis. The commonest classification is by the anatomical location of the inflammation. This includes :
The causes of uveitis are several. Some of these include :
The beginning of uveitis may usually be sudden and is described as acute. It is acute if it takes less than three months to develop and is described as chronic if it takes more than three months to develop. There may be recurrent episodes of the condition.
Diagnosis is made on the basis of clinical examination, detailed history of the disease as well as laboratory and imaging tests. A detailed history of eye injury, infections and familial diseases are obtained. The eye is examined using a slit lamp after dilating the iris. Many persons with immunosuppression or a depressed immune system are prone to uveitis. Thus immunosuppression needs to be ruled out in patients with uveitis.