Iritis

The iris is the circular, colored portion of the front of the eye with the dark pupil in the center.

The iris is made up of muscular fibers that control the amount of light entering the pupil so that we can see clearly. The iris accomplishes this task by making the pupil smaller in bright light and larger in dim light. The iris is the front part of the uveal tract of the eye (the iris in the front and the ciliary body and choroid behind it). In some people, the iris can become inflamed. This is termed iritis. If both the ciliary body and the iris are involved, the inflammatory condition is called iridocyclitis.

Inflammation of the front part of the eye is referred to as anterior uveitis or iritis, whereas inflammation behind this is known as posterior uveitis. Posterior uveitis can result in significant vision loss, especially if there is macular involvement by either inflammation or a condition known as cystoid macular edema.

Iritis may be a consequence of trauma (traumatic iritis) or nontraumatic causes. In a significant number of cases, no cause for the iritis is found.

• Blunt trauma to the eye can cause traumatic inflammation of the iris.
• Nontraumatic iritis is frequently associated with certain systemic diseases (diseases that affects multiple locations throughout the body), such as ankylosing spondylitis, Reiter syndrome, sarcoidosis, tuberculosis, inflammatory bowel disease, Behçet's disease, the HLA-B27-associated joint disorders, and psoriasis. Noteworthy of special attention is iritis associated with juvenile rheumatoid arthritis.
• Infectious causes may include Lyme disease, tuberculosis, toxoplasmosis, syphilis, and herpes simplex and herpes zoster viruses.

Iritis usually develops quickly and generally affects only one eye. Signs and symptoms may include any or all of the following:

• pain in the eye or brow region. An exception to this is iritis in patients with juvenile rheumatoid arthritis since they often do not have pain. Due to the lack of pain it may be confused with minor irritation ("pink eye") of the eye, but should not be ignored in these patients;
• worsened eye pain when exposed to bright light (photophobia);
• a red eye, especially in the white of the eye adjacent to the iris (This is caused by dilation of blood vessels.);
• small or irregularly shaped pupil;
• blurred vision;
• headache;
• increased tear production in the eye; or
• iritis may result in glaucoma and/or cataracts, leading to a marked decrease of vision.

Contact your ophthalmologist (a medical doctor who specializes in eye care and surgery) if any of the following signs or symptoms are present:

• significant eye pain, including pain associated with bright light,
• blurred vision, or
• redness in the eye, especially around the iris.

If you cannot reach your ophthalmologist, then seek medical attention at a hospital's emergency department.

• Is there any cause for the iritis?
• Are there any signs of permanent damage to the eye?
• Are there any signs of permanent vision loss?
• What are the warning signs in my individual case that I should watch for and will indicate the need to be seen right away?

The diagnosis of iritis is confirmed by examining the eye with a slit lamp (a special microscope designed for eye examination). Your ophthalmologist can see cells (white blood cells) and flare (particles of protein) in the aqueous humor (fluid that is produced in the eye).

Your physician will take a careful history looking for possible causes of iritis.

Other findings aid your ophthalmologist in diagnosing iritis.

• Topical anesthetics do not relieve the pain associated with iritis.
• Shining light in the normal, unaffected eye causes pain in the affected eye if iritis is present. This is because shining light in one eye causes both pupils to constrict. So, movement of the affected iris causes pain.
• The pressure inside the eye (so called "glaucoma test") is often lower than in the other eye (but it may be high also).
• The pupil of the eye with iritis may be much smaller or more irregular than the other eye.

Mild analgesics may help temporarily until you can see the ophthalmologist.

Iritis requires prescription medications (drops, pills, or a combination) and follow-up visits with an ophthalmologist, so seeking medical care is essential.

• Use prescription medications exactly as prescribed.
• Wear dark glasses if exposure to light is uncomfortable.
• Take mild analgesics, such as acetaminophen (Tylenol) or ibuprofen (Advil), to help control some of the discomforts.

Treatment includes the use of medication in the form of eyedrops, and pills if necessary, to promote healing and to help decrease eye pain. Eyedrops that dilate the pupil, called cycloplegics, are often used to make the eye more comfortable and to prevent adhesions of the pupil to the underlying lens.

In more severe cases, systemic steroids (cortisone) may be used.

Treatment includes the use of a medication (in the form of eyedrops or pills) to dilate (widen) the pupil and to prevent spasm of the iris muscles so that the inflamed iris can rest. This allows for healing and helps decrease the eye pain. The drops which dilate the pupil will make you more sensitive to bright lights and will cause blurring of near vision.

Steroid (cortisone) eyedrops are usually prescribed unless an infectious agent (virus or bacteria) caused the iritis. Steroid eyedrops help decrease the inflammation of the iris. If the eye does not improve within a week, your ophthalmologist may consider prescribing steroid pills or steroid injections around the eye. The length of treatment depends on the severity of disease and how well the eye improves with the treatment.

Note that these drops and pills should only be used as prescribed by your ophthalmologist since they may have serious side effects (including glaucoma and/or cataracts) in susceptible individuals.

• In all cases of iritis, follow-up care with your ophthalmologist is essential until it is resolved. In cases of nontraumatic iritis, your ophthalmologist will evaluate you for the presence of associated diseases.
• After it is healed, periodic checkups are necessary.

• Traumatic iritis usually goes away within one to two weeks. Nontraumatic iritis may take weeks, and occasionally months, to resolve.
• Infectious causes of iritis will usually resolve once measures are taken to treat the underlying infection.
• Iritis can be the cause of certain other eye problems, such as glaucoma and cataract. Occasionally, adhesions between the inflamed iris and the lens may occur. These are called posterior synechiae.
• Certain cases of iritis (those associated with systemic diseases, such as sarcoidosis or ankylosing spondylitis) may be chronic or recurrent. Ophthalmologists may instruct certain people who are at high risk of having recurrent iritis to always have steroid eyedrops on hand so that they may begin using them at the first sign of a recurrence. Try to check with your ophthalmologist first, if possible, before starting any medications.

American Academy of Ophthalmology
655 Beach Street
Box 7424
San Francisco, CA 94120
415-561-8500