May also be called: Uveitis; Iritis; Anterior Uveitis Iridocyclitis (ear-ih-doh-sy-CLY-tis) is inflammation of the iris and ciliary body, structures in the middle layer of the eye (uvea). More to Know The iris is the colored part of the eye. The dark circle at the center of the iris is the pupil. The iris controls the amount of light entering the eye through the pupil. Adjacent to the iris is the ciliary body, a ring of tissue that encircles the eye's lens. The ciliary body helps control the shape of the lens and secretes a fluid called aqueous humor that provides nutrients to the eye. Iridocyclitis occurs when both the iris and ciliary body become inflamed. This can happen due to an injury, infection, a related condition such as arthritis, or for no apparent reason. Iridocyclitis can make eyes red, painful, and sensitive to light. And in rare cases, it can eventually lead to vision loss. Keep in Mind Most cases of iridocyclitis are mild and temporary and will clear up in a few days or weeks. Iridocyclitis caused by an infection or disease usually can be corrected by treating the underlying condition. Treatment should start as early as possible to minimize the risk of vision damage. All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts. Back to Articles Related Articles Eye Injuries You can treat many minor eye irritations by flushing the eye, but more serious injuries require medical attention. Read More Eyes Although your eyes are small, their structure is incredibly complex. Find out how they work in this body basics article. Read More Eyes The eyes are small compared with most of the body's other organs, but their structure is incredibly complex. Learn more about eyes, vision, and common problems with both. Read More Your Child's Vision It's important for kids to have their eyes examined regularly, as many vision problems and eye diseases can be detected and treated early. Read More Your Eyes Ever wonder how your eyes work? This article for kids takes you from the pupil to the retina and beyond. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.