The front of the eye is covered by a clear layer called the cornea. Behind it is a fluid-filled space called the anterior chamber. Behind that is the iris. The iris is the colored part of your eye. In the center hole of the iris is the pupil. It opens and closes to control how much light enters your eye. The middle part of the eye is called the uvea. It includes the iris.
With iritis, the iris and anterior chamber are inflamed. Iritis is a type of uveitis. This is an inflammation of the uvea. Uveitis is a leading cause of blindness. Smoking increases your risk for uveitis.