Episcleritis

Dr Ben Wild

Overview

The conjunctiva is a clear layer of tissue that extends from the edge of the cornea, around the visible portion of the eye, in front of the white sclera, and even the back surface of the eyelids. It posses as a barrier against foreign material contributes to the tear film. The episclera is a second clear layer sandwiched between the conjunctiva and the white sclera. It’s function is to encapsulate the eye and help protect the contents of the orbits.

Frontal view of a healthy eye.

Episcleritis is a common condition, usually without a known cause, often occurring in both eyes, involving inflammation of the episclera. This condition can be recurrent and, if so, is more likely to be associated with known conditions. Unlike conjunctivitis, where the blood vessels are straight or wavy, episcleral vessels are radial.

There are two main types of episcleritis. Simple episcleritis is 75% of cases and usually peaks at the 24-hour mark after it has been first noticed, then fades. It presents as sectoral (small patch) or diffuse (all-over) redness of the eye. Nodular episcleritis develops very slowly and takes much longer to resolve. It often presents as pain upon awakening, redness worsens and becomes uncomfortable when it develops into a nodule.

Front view of an eye with nodular episcleritis on the left of the picture and simple sectoral episcleritis on the right.

Signs and Symptoms

Signs

Simple	Flat areas of inflamed blood vessels, over 50% are in both eyes, either the entire episcleral or a sector, often triangular, swelling.
Nodular	A bump (nodule) surrounded by inflamed blood vessels.

Symptoms

Simple	No symptoms to severe discomfort, grittiness and light sensitivity.
Nodular	Discomfort, grittiness, light sensitivity.

Causes and Risk Factors

Causes

Inflammation of the episclera.

Risk factors

Dry eyes, rosacea, contact lens wear, collagen vascular diseases like rheumatoid arthritis, shingles.

Prevention and Treatment

Prevention

There are no known preventative measures.

Treatments

· Most episodes do not need treatment.

· Artificial tears.

· Cold compresses.

· Non-steroidal anti-inflammatory pill or drop.

· Steroid drop.

Prognosis

Episcleritis is not a condition that can affect long term vision or eye health. Although, depending on the cause, it could spread to a different tissue type that could affect the health of the eye, like scleritis. Recurrent episodes can lead to the blood vessels of the eye becoming permanently enlarged.