EPISCLERITIS

Episcleritis is benign recurrent inflammation of the episclera, involving the overlying Tenon's capsule but not the underlying sclera. It typically affects young adults, being twice as common in women than men.

Etiology

Exact etiology is not known.

•  It is found in association with gout, rosacea and psoriasis.

•  It has also been considered a hypersensitivity reaction to endogenous tubercular or streptococcal toxins.

Pathology

Histologically, there occurs localised lymphocytic infiltration of episcleral tissue associated with oedema and congestion of overlying Tenon's capsule and

conjunctiva.

Clinical picture

Symptoms. Episcleritis is characterised by redness, mild ocular discomfort described as gritty, burning or foreign body sensation. Many a time it may not be

accompanied by any discomfort at all. Rarely, mild photophobia and lacrimation may occur. Signs. On examination two clinical types of episcleritis, diffuse (simple) and nodular may be recognised. Episclera is seen acutely inflamed in the

involved area.

• In diffuse episcleritis, although whole eye may be involved to some extent, the maximum inflammation is confined to one or two quadrants (Fig. 6.2A).

• In nodular episcleritis, a pink or purple flat nodule surrounded by injection is seen, usually

situated 2-3 mm away from the limbus (Fig. 6.2B).The nodule is firm, tender and the overlying conjunctiva moves freely. 

Clinical course. Episcleritis runs a limited course of 10 days to 3 weeks and resolves spontaneously. However, recurrences are common and tend to occur in bouts. Rarely, a fleeting type of disease (episcleritis periodica) may occur.

Differential diagnosis

Occasionally episcleritis may be confused with inflamed pinguecula, swelling and congestion due to foreign body lodged in bulbar conjunctiva and very rarely with scleritis.

B

Fig. 6.2. Episcleritis: A, Diffuse; B, Nodular.