DISORDERS OF ORBIT

Exophthlamos (proptosis) denotes abnormal protrusion of eye ball, due to: (a) shallow orbit, as in craniofacial malformations, (b) increased orbital mass, e.g. ocular inflammations and tumors, or (c) posterior push on eye ball, e.g.

Precise severity of proptosis may be measured by exo­phthalmometer, as distance between lateral orbital rim to apex of cornea. An absolute value of gt;20 mm or gt;2 mm difference between two sides as abnormal. Apart from causative pathology, exophthalmos per se may lead to exposure keratoconjunctivitis and refractive errors due to deformed ocular shape.

Enophthalmos is usually secondary to orbital fracture or post-inflammatory atrophy of orbital tissue, presenting as posterior sinking of eye. It should be differentiated from congenital micropthalmia, which is common in intrauterine infections.

Orbital cellulitis, i.e. inflammation of orbital tissue may develop due to: (a) direct orbital infection, e.g. trauma, (b) as part of generalized septicemia, or (c) extension of infection from neighbouring tissues, e.g. sinusitis (commonest cause in children). Common causative organisms in children are Staph. aureus, H. Influenza and anaerobic organisms.

Clinically, it presents with: (a) proptosis, (b) restricted eye movements, (c) chemosis and/or lid swelling, with or without pain.

Prompt therapy with systemic antibiotics and surgical drainage of abscess, if present, is essential to prevent secondary complications, i.e. intracranial extension with cavernous sinus thrombosis, meningitis or brain abscess.

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