What is Iritis?

Your eye doctor may have diagnosed that you have a condition known as iritis. This is a condition where a part of the eye, the iris, becomes inflamed. With proper treatment an attack of iritis can be controlled.

What are the signs of iritis?

Eye pain (may be severe)

Blurred or decreased vision

Sensitivity to light (photophobia)

Red eye

Tears

Smaller pupil on affected eye (sometimes)

Red right eye in iritis

It is more common for just one eye to be affected during an attack of iritis. However both eyes can be affected at the same time.  

Generally, the eye is not sticky, crusty or producing a discharge. These are symptoms more suggestive of conjunctivitis.

What is the iris?

The iris is the structure behind the cornea of the eye which dilates and constricts.  In bright light, the iris constricts (you may have noticed this yourself).  In dim light, it dilates.

Image created by Mark Erickson, CRA, COT
Image from www.stlukeseye.com/anatomy.htm

What is the difference between the iris and the pupil?

The pupil is defined as the the hole in the middle of the iris.  The iris is the structure which is around the hole and defines the hole. 

Image from American Academny of Ophthalmology

 

Are there different kinds of iritis? What is the difference between iritis and uveitis?

Yes. Iritis is the commonest of a family of conditions called uveitis. The uvea extends from the front of the eye to the back of the eye. Where the uvea is inflamed at the front of the eye involving the iris, uveitis is synonymous with iritis. Where it inflamed near the middle of the eye involving the ciliary body, it is called cyclitis. When the back of the eye involving the choroid is inflamed, it is called choroiditis.

What are the causes of iritis?

Unknown (this is the most common)

Certain medical conditions such as:

  1. Ankylosing spondylitis

  2. Ulcerative colitis

  3. Crohn’s disease

  4. Sarcoidosis

Injury to the eye

Surgery to the eye

Infections such as:

  1. Shingles or chickenpox virus (herpes zoster)

  2. Cold sore virus (herpes simplex)

  3. Parasite, eg toxoplasmosis

Is iritis contagious?

Very few people with iritis have a contagious variety. If you do, your doctor will tell you.

Can attacks of iritis be prevented?

Generally speaking, no. No-one knows why people have recurrent attacks at particular times. There is published evidence that earthquake victims have much higher rates of recurrence so some doctors think stress may be a factor.

How is iritis diagnosed?

When symptoms occur, a prompt examination by an ophthalmologist (medical doctor specializing in the eye) is important. If left untreated, inflammation in the eye can lead to permanent damage or even in extreme cases blindness.

The ophthalmologist will use instruments to examine the inside of the eye and can usually make the diagnosis on that basis. Since uveitis can be associated with disease elsewhere in the body, he will require a thorough understanding of your overall health. This may involve consultation with other medical specialists. He may also request blood tests, X-rays, and other specialized tests to establish a cause of the uveitis.

How is iritis treated?

Eye drops, especially steroids (such as Prednisolone [PredForte]or Dexamethasone [Maxidex]) and pupil dilators, are medications used to reduce inflammation and pain in the front of the eye. The steroid drops may need to be instilled frequently (in severe cases as much as every half an hour). Your ophthalmologist will arrange to see you again to assess the progress of the treatment and will, according to the degree of inflammation, decrease or increase the treatment.

Pupil dilating drops (such as Cyclopentolate [Mydrilate] or Atropine) make you feel more comfortable and prevent certain complications of iritis. However you may become more sensitive to bright light, especially during the summer, and you may lose the ability to focus on near objects (accommodation), and your vision may become more blurred.

Aren’t steroids harmful?

Steroids taken by mouth have side-effects. However steroid eye drops are absorbed principally by the eye and do not cause the same side-effects as oral steroids. In a small proportion of people steroid eye drops cause the pressure in the eye to rise above normal. Your ophthalmologist will measure the pressure in the eye to discover if you are one of these people and will treat you accordingly.

What are the possible complications of uveitis?

In most cases complications are rare, but they include:

Glaucoma (high pressure in the eye causing damage)

Cataract (clouding of the lens of the eye)

New blood vessel formation (neovascularization)

These complications may themselves need treatment. If complications are advanced, conventional or laser surgery may be required.

What is the probable outcome?

Uveitis arising in the front or middle of the eye (iritis or cyclitis) is commonly more sudden in onset, generally lasting six to eight weeks, and in early stages can usually be controlled by the frequent use of drops. Often, this type of uveitis cannot be given a specific cause.

Uveitis in the back part of the eye (choroiditis) is commonly slower in onset and may last longer, and is often more difficult to treat. Treatment may involve steroid tablets or injections. Often, multiple tests are required to find the cause of this type of uveitis.

With infections, uveitis tends to clear up once the underlying infection is treated.

Are there any restrictions to what I can do?

You should not drive a car if you can’t see properly. Dark glasses will make you feel more comfortable. Whether you will need to give up work depends on the severity of the symptoms. There is no special diet required.

Back to iritis.com home