Orbital cellulitis
Orbital cellulitis is infection of the fat and muscle posterior to the orbital septum, most often from spreading sinusitis, that causes proptosis, painful ophthalmoplegia, and vision loss and can progress to cavernous sinus thrombosis. It is a vision- and life-threatening emergency treated with admission, blood and tissue culture, orbital/sinus CT or MRI, and immediate empiric IV vancomycin plus ceftriaxone with ophthalmology and ear, nose, and throat (ENT) involvement.
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What this article covers
- Overview
Definition: infection of the orbital fat and extraocular muscles posterior to the orbital septum, sparing the globe, threatening vision and life through optic nerve compromise or intracranial spread.
- Epidemiology
Occurs in both children and adults; children carry a disproportionate burden from their higher rate of sinusitis.
- Risk factors
Acute or chronic sinusitis, especially ethmoid sinusitis: the ethmoid sinus is separated from the orbit only by the thin lamina papyracea, the most common route of contiguous spread.
- Pathophysiology
Contiguous extension from the paranasal sinuses is the dominant mechanism: infection tracks through thin bony walls (most often the lamina papyracea) or via valveless emissary veins into the orbital fat and extraocular muscles.
- Clinical features
Painful, restricted extraocular movement (ophthalmoplegia) is the hallmark separating orbital from preseptal disease: pain and limitation with eye movement in any direction indicates postseptal (muscle/fat) involvement.
- Differential diagnosis
Preseptal (periorbital) cellulitis: eyelid edema and erythema without pain on eye movement, restricted motility, proptosis, or diplopia; the single most important distinction because urgency and management differ.
- Diagnosis
Orbital cellulitis is a clinical diagnosis: confirmed by proptosis, painful/restricted extraocular movement, and diplopia (with or without decreased acuity or a relative afferent pupillary defect) in…
- Management
Admit every confirmed or strongly suspected case for intravenous antibiotics with same-day ophthalmology consultation and ear, nose, and throat (ENT) consultation for the underlying sinus source; do…
- Complications
Cavernous sinus thrombosis: the most feared complication, from posterior spread through the valveless orbital venous system; causes complete ophthalmoplegia that can extend to the contralateral eye, plus retrobulbar pain and blindness.
- Prognosis
Good outcome with prompt recognition and treatment: most patients recover fully with early admission, intravenous antibiotics, and drainage of any abscess.
- Prevention
Treat acute bacterial sinusitis promptly, particularly ethmoid sinusitis, to prevent contiguous orbital spread: criteria favoring a bacterial (not viral) cause and antibiotics are symptoms lasting…
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Related articles
- Preseptal cellulitis
Preseptal (periorbital) cellulitis is infection of the eyelid and periorbital soft tissue anterior to the orbital septum, most often from S. aureus or streptococci, confirmed by preserved pain-free eye movements and normal vision that exclude orbital cellulitis. First-line therapy is oral amoxicillin-clavulanate 875/125 mg every 12 hours for 5 to 10 days, with MRSA coverage added for a traumatic portal.
- Cavernous sinus thrombosis
Septic thrombosis of the cavernous sinus from spreading facial, sinus, or orbital infection, marked by fever, proptosis, chemosis, and cranial nerve palsies that classically become bilateral. It is a neuro-ophthalmic emergency treated with immediate broad-spectrum IV antibiotics, source control, and consideration of anticoagulation.
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Mucormycosis is a rapidly progressive, angioinvasive mold infection caused by Rhizopus and Mucor species that thrive in diabetic ketoacidosis, neutropenia, and iron-overload states. Diagnosis rests on biopsy showing broad, nonseptate hyphae in necrotic tissue, and first-line treatment combines urgent surgical debridement with high-dose liposomal amphotericin B, stepped down to posaconazole or isavuconazole; mortality remains 60 to 80 percent.