Iridocyclitis is a type of inflammation in the eye that may be caused by an injury, infection or autoimmune condition. Iridocyclitis is a type of uveitis, a general term referring to inflammation of the uvea, the middle layer of the eye. The uvea contains the iris, the ciliary body and the choroid.

Uveitis is typically divided into three categories: 

• Anterior – Inflammation of the iris or iris and ciliary body
• Intermediate – Inflammation of the ciliary body
• Posterior – Inflammation of the choroid 

If the entire uvea is inflamed, that's known as diffuse uveitis.

Anterior uveitis is the most common of the three types and can be broken down into:

• Iritis – Inflammation of the iris
• Iridocyclitis – Inflammation of the iris and the ciliary body, a part of the eye behind the iris that helps you focus on nearby objects

Here's a guide to the causes and symptoms of iridocyclitis, and why seeing your eye doctor right when you notice symptoms may help to prevent vision loss.

The specific cause of a case of iridocyclitis is oftentimes unknown. In fact, as many as one in three cases may have no known cause. In some cases, iridocyclitis can be caused by injury (traumatic iridocyclitis) or by infections or other factors (non-traumatic iridocyclitis).

Traumatic iridocyclitis may be caused by any type of injury to the eye, such as chemical burns, blunt force trauma or a poke in the eye. In these cases, the inflammation and swelling tend to lessen over a few weeks as the eye heals. However, there may be lasting vision problems caused by the injury.

Non-traumatic iridocyclitis may also be caused by a variety of infections and illnesses, including: 

• Bacterial infection, such as Lyme disease, syphilis, toxoplasmosis, tuberculosis
• Parasitic infection, such as toxoplasmosis
• Viral infection, such as herpes simplex, eye shingles caused by herpes zoster
• Adverse reaction to a medication
• Autoimmune disease, such as eyelid psoriasis,  juvenile rheumatoid arthritis or systemic lupus erythematosus
• Compromised immune system, such as caused by HIV/AIDS
• Inflammatory condition, such as inflammatory bowel disease or sarcoidosis

An eye doctor will need to do an exam and take a health history to diagnose and try to find the cause of iridocyclitis. Occasionally, laboratory and radiology tests are ordered to assist in identifying the underlying cause.

Symptoms and signs of iridocyclitis may include:

• Mild redness
• Blurry vision
• Eye pain
• Headache
• Sensitivity to light (photophobia)

Signs of iridocyclitis may be similar to those of other eye problems, including conjunctivitis, a corneal abrasion or a foreign object in the eye.

It can cause vision problems or even vision loss if left untreated, so it's important to see your eye doctor right away if you experience any symptoms to ensure you get a proper assessment and appropriate treatment.

An eye doctor will treat iridocyclitis to reduce inflammation, manage eye pain and prevent complications that could lead to vision loss.

Treatment for iridocyclitis may include eye drops to dilate the pupil, prevent spasms and reduce inflammation in the eye. For example, your eye doctor may prescribe one or more of these eye medications:

• Anticholinergics – Used to treat light sensitivity and eye pain
• Topical steroids – Used to decrease inflammation in the eye. Note that steroids require that you follow dosing instructions to prevent other complications.

Patients who have iridocyclitis due to certain health conditions may need additional treatment. For example: 

• A patient with a bacterial infection may also need antibiotics to treat the underlying infection.
• Patients with certain types of arthritis or inflammatory bowel disease may also need drugs known as tumor necrosis factor blockers (e.g., adalimumab or infliximab) to help prevent vision loss. 

Your eye doctor will need to see you for eye exams every few days while you're getting treatment. It's important for them to monitor your eye pressure because a sudden pressure change can harm your vision. You may need to follow up every one to six months after you're done with initial treatment as well.

Iridocyclitis is a type of uveitis, an “umbrella” condition that is fairly rare in the United States. In fact, there are only about 38 cases of uveitis per 100,000 people.

Anterior uveitis makes up more than nine in 10 cases of uveitis. The other types of uveitis — intermediate and posterior — are far less common. However, multiple forms of uveitis can occur simultaneously.

Untreated iridocyclitis can lead to cataracts, glaucoma, an irregular pupil, vision loss or blindness. Fortunately, patients who seek diagnosis and treatment right away typically have a good prognosis. Only around 10% to 30% of cases may need continuing treatment to prevent vision loss.

If you experience signs of iridocyclitis, make an appointment with your eye doctor right away. Getting an immediate exam and treatment is one of the best ways to prevent or minimize vision loss. It's also important to have regular eye exams to keep your eyes healthy.

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