Iritis (i-RYE-tis) is inflammation that affects the coloured ring around your eye's pupil (iris). The iris is a circular pigmented membrane that provides the eye its colour and is made up of muscular fibres that control the amount of light entering you're eye, so that you can see clearly. It does this by making the pupil smaller in bright light, and bigger in dim light.
The iris is a part of the middle layer of the eye (uvea), so iritis is a type of uveitis, also known as anterior uveitis.
Iritis, the most common type of uveitis, affects the front of your eye. The cause is often unknown. It can result from an underlying systemic condition or a genetic factor.
Iritis attacks the eye quickly and in most cases, occurs in one eye at a time. There are two forms of iritis, acute and chronic. Acute iritis if treated immediately will improve and heal quickly. Chronic iritis doesn't respond as well to medication and can take months or years to heal. Chronic iritis can also cause serious visual impairment if not treated, iritis can lead to glaucoma or vision loss. If you have symptoms of iritis, see your doctor as soon as possible.
It usually develops suddenly, and can last six to eight weeks. Signs and symptoms of iritis include:
• Eye redness
• Discomfort or achiness in the affected eye
• Sensitivity to light (photophobia)
• Decreased vision
Iritis that develops suddenly, over hours or days, is known as acute iritis. Symptoms that develop gradually or last longer than six weeks indicate chronic iritis.
Your eye doctor will conduct a complete eye exam, including:
• External eye examination.
• Visual acuity.
• Slit-lamp examination. Dilating your pupil with eye drops enables your doctor to see the inside of your eye better.
Your eye doctor may work with your GP to pinpoint an underlying cause. In that case, further testing might include blood tests or X-rays to identify or rule out specific causes
Risk Factors & causes of Iritis include:
Injury to the eye. Blunt force trauma, a penetrating injury, or a burn from a chemical or fire.
Infections. Shingles (herpes zoster) on your face. Other infectious diseases, such as toxoplasmosis, histoplasmosis, tuberculosis and syphilis, can be linked to other types of uveitis.
Genetic predisposition. People who develop certain autoimmune diseases due to a gene alteration (labelled HLA-B27)that affects their immune systems might also develop acute iritis.
Diseases include ankylosing spondylitis, reactive arthritis formally known as Reiter's syndrome, inflammatory bowel disease and psoriatic arthritis.
Behcet's disease. An uncommon cause of acute iritis in Western countries, this condition is also characterized by joint problems, mouth sores and genital sores.
Juvenile rheumatoid arthritis. Chronic iritis can develop in children with this condition.
Sarcoidosis. This autoimmune disease involves the growth of collections of inflammatory cells (granulomas) in areas of your body, including your eyes.
Certain medications. A rare cause of Iritis
Sexually transmitted infection. Certain infections, such as syphilis or HIV/AIDs, are linked with a significant risk of iritis.
If not treated properly, iritis could lead to:
• An irregular pupil.
• Calcium deposits on the cornea (band keratopathy).
The secrets to the successful treatment of iritis is early detection and proper choice of medicines. Therapy consists of anti-inflammatory and dilating drops. These drops often must be instilled 1 hourly -2 hourly. These medicines decrease the inflammation, reduce the scarring that can occur, and improve comfort levels. Dark glasses will also aid in making the eye more comfortable.
Persistent cases may require more intensive treatment. Successful treatment of iritis depends on careful and consistent compliance by the patient. Follow up care is essential.