Periorbital cellulitis

Periorbital cellulitis, also known as preseptal cellulitis, is an inflammation and infection of the eyelid and portions of skin around the eye. It may be caused by breaks in the skin around the eye, and subsequent spread to the eyelid; infection of the sinuses around the nose (sinusitis); or from spread of an infection elsewhere through the blood.

Characteristics
Periorbital cellulitis must be differentiated from orbital cellulitis, which is an emergency and requires intravenous (IV) antibiotics. In contrast to orbital cellulitis, patients with periorbital cellulitis do not have bulging of the eye (proptosis), limited eye movement (ophthalmoplegia), pain on eye movement, and loss of vision. If any of these features is present, one must assume that the patient has orbital cellulitis and begin treatment with IV antibiotics. CT scan may be done to delineate the extension of the infection.

Causes
Staphylococcus and streptococcus species are commonly implicated. The advent of the Haemophilus influenzae vaccine has dramatically decreased the incidence of periorbital and orbital cellulitis.