orbital cellulitis
A serious bacterial infection involving structures posterior to the orbital septum, causing proptosis, decreased extraocular movements, and potential vision loss.
Full Definition
Orbital cellulitis is a potentially sight-threatening and life-threatening bacterial infection that involves the tissues and muscles within the orbit, posterior to the orbital septum. Unlike periorbital cellulitis, orbital cellulitis presents with proptosis, decreased or painful extraocular movements, decreased visual acuity, and may cause diplopia. The condition is often a complication of ethmoid sinusitis and requires immediate treatment with broad-spectrum intravenous antibiotics. Complications can include subperiosteal or orbital abscess formation, cavernous sinus thrombosis, meningitis, and permanent vision loss. Imaging with CT or MRI is typically required to assess the extent of infection and identify complications that may require surgical drainage.
Usage
Usage note: Considered a pediatric emergency requiring immediate intervention; distinguish carefully from periorbital cellulitis.
In Context
- "The child's orbital cellulitis required urgent ophthalmologic consultation and IV antibiotics." — Emergency department critical action
- "CT imaging revealed orbital cellulitis with concerning subperiosteal abscess formation." — Radiology report interpretation