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Cavernous Sinus Thrombosis


James Garrity

, MD, Mayo Clinic College of Medicine and Science

Last full review/revision Aug 2021| Content last modified Sep 2022
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Cavernous sinus thrombosis is a very rare, typically septic thrombosis of the cavernous sinus, usually caused by nasal furuncles or bacterial sinusitis. Symptoms and signs include pain, proptosis, ophthalmoplegia, vision loss, papilledema, and fever. Diagnosis is confirmed by CT or MRI. Treatment is with IV antibiotics. Complications are common, and prognosis is guarded.

Etiology of Cavernous Sinus Thrombosis

The cavernous sinuses are trabeculated sinuses located at the base of the skull that drain venous blood from facial veins. Cavernous sinus thrombosis is an extremely rare complication of common facial infections, most notably nasal furuncles (50%), sphenoidal or ethmoidal sinusitis Sinusitis Sinusitis is inflammation of the paranasal sinuses due to viral, bacterial, or fungal infections or allergic reactions. Symptoms include nasal obstruction and congestion, purulent rhinorrhea... read more Sinusitis (30%), and dental infections (10%). Most common pathogens are Staphylococcus aureus (70%), followed by Streptococcus species; anaerobes are more common when the underlying condition is dental or sinus infection.

Pathophysiology of Cavernous Sinus Thrombosis

Symptoms and Signs of Cavernous Sinus Thrombosis

Initial symptoms of cavernous sinus thrombosis are progressively severe headache or facial pain, usually unilateral and localized to retro-orbital and frontal regions. High fever is common. Later, ophthalmoplegia (typically the 6th cranial nerve in the initial stage), proptosis, and eyelid edema develop and often become bilateral. Facial sensation may be diminished or absent. Decreased level of consciousness, confusion, seizures, and focal neurologic deficits are signs of central nervous system (CNS) spread. Patients with cavernous sinus thrombosis may also have anisocoria or mydriasis (3rd cranial nerve dysfunction), papilledema Papilledema Papilledema is swelling of the optic disk due to increased intracranial pressure. Optic disk swelling resulting from causes that do not involve increased intracranial pressure (eg, malignant... read more Papilledema , and vision loss.

Diagnosis of Cavernous Sinus Thrombosis

  • MRI or CT

Cavernous sinus thrombosis is often misdiagnosed because it is rare. It should be considered in patients who have signs consistent with orbital cellulitis Preseptal and Orbital Cellulitis Preseptal cellulitis (periorbital cellulitis) is infection of the eyelid and surrounding skin anterior to the orbital septum. Orbital cellulitis is infection of the orbital tissues posterior... read more Preseptal and Orbital Cellulitis . Features that distinguish cavernous sinus thrombosis from orbital cellulitis include cranial nerve dysfunction, bilateral eye involvement, and mental status changes.

Prognosis of Cavernous Sinus Thrombosis

Mortality in the antibiotic era is about 15 to 20%. An additional 40% develop serious sequelae (eg, ophthalmoplegia, blindness, disability due to stroke, pituitary insufficiency), which may be permanent.

Treatment of Cavernous Sinus Thrombosis

  • IV high-dose antibiotics

  • Sometimes corticosteroids

Initial antibiotics for patients with cavernous sinus thrombosis include nafcillin or oxacillin 1 to 2 g every 4 to 6 hours combined with a 3rd-generation cephalosporin (eg, ceftriaxone 1 g every 12 hours). In areas where methicillin-resistant S. aureus is prevalent, vancomycin 1 g IV every 12 hours should be substituted for nafcillin or oxacillin. A drug for anaerobes (eg, metronidazole 500 mg every 8 hours) should be added if an underlying sinusitis or dental infection is present.

In cases with underlying sphenoid sinusitis Treatment Sinusitis is inflammation of the paranasal sinuses due to viral, bacterial, or fungal infections or allergic reactions. Symptoms include nasal obstruction and congestion, purulent rhinorrhea... read more Treatment , surgical sinus drainage is indicated, especially if there is no clinical response to antibiotics within 24 hours.

Secondary treatment for cavernous sinus thrombosis may include corticosteroids (eg, dexamethasone 10 mg IV or orally every 6 hours) for cranial nerve dysfunction; anticoagulation is controversial because most patients respond to antibiotics, and adverse effects may exceed benefits.

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

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