Anterior Uveitis (Iritis)

What is Anterior Uveitis (Iritis)?

Anterior uveitis, also known as iritis, is an inflammation of the uvea, specifically the iris (the coloured part of the eye) and the ciliary body. It is the most common type of uveitis.

It requires prompt medical treatment to prevent complications such as glaucoma, cataracts, or permanent vision loss.

Causes

In many cases, the exact cause is unknown. However, it can be associated with:

• Autoimmune disorders (e.g., ankylosing spondylitis, inflammatory bowel disease, psoriasis)
• Genetic factors (presence of the HLA-B27 gene)
• Infections (e.g., herpes simplex, shingles, syphilis, Lyme disease)
• Eye trauma or surgery

Symptoms

Symptoms usually develop quickly (over a few hours or days) and typically affect one eye, though both can be involved.

• Eye pain: Often a deep, dull ache that worsens when focusing or in bright light.
• Redness: Particularly a deep red ring around the iris.
• Photophobia: Severe sensitivity to light.
• Blurred vision
• Small pupil: The pupil may appear smaller than the other eye or irregularly shaped.

Treatment

Treatment aims to reduce inflammation, relieve pain, and prevent complications.

• Steroid eye drops: The mainstay of treatment to reduce inflammation. These must be used exactly as prescribed and tapered off slowly under medical supervision.
• Dilating eye drops (e.g., cyclopentolate or atropine): These dilate the pupil and relax the muscles in the eye, which significantly relieves pain and prevents the iris from sticking to the lens (synechiae). They will make your vision blurry and sensitive to light.

When to Seek Urgent Help

If you experience a painful, red eye with sensitivity to light and blurred vision, you should seek urgent assessment by an ophthalmologist or at an eye casualty department. Do not wait.