In dim light, the iris opens up the pupil wide to let in as much light as possible.

In bright light, the iris dials back the pupil, making it smaller. The iris is the most anterior portion of the uvea for this reason, iritis also is known as anterior uveitis.Ī thin, circular structure composed of connective tissue and muscle, the iris expands and contracts in response to light, helping us to see clearly. The iris is part of the pigmented middle layer of the eye known as the uvea, which includes the iris, ciliary body and choroid. Prompt diagnosis and treatment by an eye doctor is advised. There are potentially serious complications associated with iritis, including cataracts, glaucoma, retinal damage and vision loss.

The inflammation usually develops quickly and typically in just one eye, although both eyes can be affected. Iritis is inflammation of the iris, the circular structure inside the eye that surrounds the pupil and gives your eyes their color.