Pathophysiology of Orbital Cellulitis

Orbital cellulitis results from microbial infection with subsequent
inflammation of the post-septal aspect of the eyelids. The most common routes of infection
are from adjacent sinuses or teeth, and direct inoculation through penetrating lid injury.
Common organisms include Staphylococcus aureus, Streptococcus pyogenes, Streptococcus
pneumoniae, and Haemophilus influenzae in children. There is significant potential
morbidity and even mortality as a post-septal lid infection can spread through a valveless
venous system leading to cavernous sinus thrombosis, meningitis, intracranial infection,
and septicemia.

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