Proptosis

Background

• Proptosis (exophthalmos) is forward displacement of the eye from the orbit
• In the ED, the key concern is distinguishing emergent causes requiring immediate intervention from non-emergent etiologies
• Unilateral acute proptosis with pain, vision loss, or elevated IOP is an emergency — consider retrobulbar hemorrhage, orbital cellulitis, or cavernous sinus thrombosis
• Bilateral proptosis is most commonly Graves' disease
• Retrobulbar hemorrhage with elevated IOP requires emergent lateral canthotomy

Clinical Features

Proptosis in a woman with retrobulbar abscess and orbital cellulitis.

History

• Unilateral vs. bilateral
• Onset: acute (hours — retrobulbar hemorrhage, orbital cellulitis) vs. subacute (days — infection, inflammatory) vs. chronic (weeks-months — thyroid, tumor)
• Pain: severe with infection, hemorrhage, or inflammation; painless suggests tumor or thyroid
• Vision changes, diplopia
• Recent trauma or surgery (retrobulbar hemorrhage)
• Fever (orbital cellulitis, cavernous sinus thrombosis)
• Recent sinusitis or dental infection (orbital cellulitis)
• Known thyroid disease
• Immunosuppression, diabetes (mucormycosis risk)

Physical Exam

• Visual acuity (each eye) — decreased acuity indicates optic nerve compromise
• Pupillary exam: RAPD (afferent pupillary defect) indicates optic nerve compression
• Extraocular movements: restricted in orbital cellulitis, cavernous sinus thrombosis, retrobulbar process
• Intraocular pressure (IOP measurement) — elevated >40 mmHg with tense orbit suggests retrobulbar hemorrhage
• Resistance to retropulsion (push gently on closed eyelid — firm/tense orbit is abnormal)
• Assess for chemosis (conjunctival swelling), periorbital edema, erythema
• Fundoscopy: look for optic disc edema, retinal vessel pulsations
• Cranial nerves III, IV, VI (affected in cavernous sinus thrombosis)
• Nasal exam for black eschar (mucormycosis)

Red Flags

• Acute onset with vision loss — retrobulbar hemorrhage (needs emergent canthotomy)
• IOP >40 mmHg with RAPD — retrobulbar hemorrhage
• Fever + proptosis + pain with eye movement — orbital cellulitis
• Bilateral proptosis + CN palsies + fever — cavernous sinus thrombosis
• Immunocompromised + necrotic nasal tissue — mucormycosis
• Pulsatile proptosis with bruit — carotid-cavernous fistula

Differential Diagnosis

Emergent

• Retrobulbar hemorrhage (post-traumatic or post-surgical)
• Orbital cellulitis (frequently from adjacent sinusitis)
• Cavernous sinus thrombosis (bilateral cranial nerve palsies, septic appearance)
• Mucormycosis (immunocompromised, diabetic ketoacidosis)

Urgent

• Carotid-cavernous fistula (pulsatile proptosis, orbital bruit, chemosis)
• Orbital abscess (complication of orbital cellulitis)
• Orbital hematoma (trauma)

Subacute/Chronic

• Graves' disease (most common cause of bilateral proptosis; can be unilateral)
• Orbital tumors (lymphoma, rhabdomyosarcoma in children, meningioma, metastases)
• Orbital pseudotumor (idiopathic orbital inflammation)
• Orbital fractures with soft tissue swelling

Periorbital swelling

Proptosis

• Normal IOP
  • Orbital cellulitis
  • Orbital pseudotumor
  • Orbital tumor
• Increased IOP
  • Retrobulbar abscess
  • Retrobulbar emphysema
  • Retrobulbar hemorrhage
  • Ocular compartment syndrome
  • Orbital tumor

No proptosis

• Periorbital cellulitis/erysipelas
• Dacryocystitis (lacrimal duct)
• Dacryocele/Dacryocystocele
• Dacryostenosis
• Dacryoadenitis (lacrimal gland)
• Allergic reaction
• Nephrotic Syndrome (pediatrics)

Lid Complications

• Blepharitis (crusts)
• Chalazion (meibomian gland)
• Stye (hordeolum) (eyelash folicle)

Other

• Subperiosteal abscess
• Orbital abscess
• Cavernous sinus thrombosis
• Conjunctivitis
• Contact dermatitis
• Herpes zoster
• Herpes simplex
• Sarcoidosis
• Granulomatosis with polyangiitis

Evaluation

Bedside

• Visual acuity
• IOP measurement (see Tono-Pen use)
• Pupillary exam for RAPD
• Extraocular movements
• POCUS: may identify retrobulbar hemorrhage or abscess

Imaging

• CT orbits with contrast (and maxillofacial cuts): primary imaging modality
  • Evaluates for retrobulbar hemorrhage, orbital abscess, sinusitis, fracture, foreign body, mass
  • CT angiography if vascular cause suspected (carotid-cavernous fistula)
• MRI/MRV: better for cavernous sinus thrombosis, tumor characterization, optic nerve evaluation (non-emergent)

Laboratory

• CBC, BMP, blood cultures if infection suspected
• ESR, CRP for inflammatory process
• TSH, free T4 if Graves' disease suspected
• HbA1c, glucose if mucormycosis concern (often in DKA patients)
• Coagulation studies if on anticoagulation

Management

Retrobulbar Hemorrhage

• Emergent lateral canthotomy and cantholysis — do not delay for imaging if clinical diagnosis is clear (tense orbit, elevated IOP >40, RAPD, vision loss)
• This is a bedside procedure that can be sight-saving
• Ophthalmology consultation (but do not delay canthotomy for consult)

Orbital Cellulitis

• IV antibiotics: broad-spectrum coverage for sinusitis-related pathogens
  • Typical regimen: vancomycin + ceftriaxone +/- metronidazole (or ampicillin-sulbactam)
• Ophthalmology and ENT consultation
• Surgical drainage if subperiosteal or orbital abscess identified on CT
• See Orbital cellulitis for detailed management

Cavernous Sinus Thrombosis

• IV antibiotics (similar to orbital cellulitis)
• Anticoagulation is controversial; consider hematology consultation
• ICU admission

Mucormycosis

• Amphotericin B (liposomal preferred)
• Emergent ENT consultation for surgical debridement
• Correct underlying metabolic derangement (DKA)
• High mortality — aggressive early treatment essential

Graves' Disease

• If mild: artificial tears, head-of-bed elevation, sunglasses
• If sight-threatening (compressive optic neuropathy): high-dose IV corticosteroids, urgent ophthalmology
• Endocrinology referral

Disposition

Admit

• Retrobulbar hemorrhage (post-canthotomy monitoring)
• Orbital cellulitis requiring IV antibiotics
• Cavernous sinus thrombosis (ICU)
• Mucormycosis (ICU)
• Any vision-threatening proptosis

Discharge

• Chronic Graves' ophthalmopathy without acute vision changes — arrange ophthalmology and endocrinology follow-up
• Mild preseptal cellulitis (NOT orbital) — oral antibiotics with close follow-up in 24-48 hours
• Return precautions: vision changes, worsening pain, fever, increasing swelling

See Also

• Lateral Canthotomy
• Globe luxation reduction
• Orbital cellulitis
• Periorbital swelling
• Eye Exam