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 (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.
Thrombosis of the lateral sinus (related to mastoiditis Mastoiditis Mastoiditis is a bacterial infection of the mastoid air cells, which typically occurs after acute otitis media. Symptoms include redness, tenderness, swelling, and fluctuation over the mastoid... read more ) and thrombosis of the superior sagittal sinus (related to bacterial meningitis Acute Bacterial Meningitis Acute bacterial meningitis is rapidly progressive bacterial infection of the meninges and subarachnoid space. Findings typically include headache, fever, and nuchal rigidity. Diagnosis is by... read more ) occur but are rarer than cavernous sinus thrombosis.
Pathophysiology of Cavernous Sinus Thrombosis
The 3rd, 4th, and 6th cranial nerves and the ophthalmic and maxillary branches of the 5th cranial nerve are adjacent to the cavernous sinus and are commonly affected in cavernous sinus thrombosis. Complications of cavernous sinus thrombosis include meningoencephalitis, brain abscess Brain Abscess A brain abscess is an intracerebral collection of pus. Symptoms may include headache, lethargy, fever, and focal neurologic deficits. Diagnosis is by contrast-enhanced MRI or CT. Treatment is... read more , stroke Overview of Stroke Strokes are a heterogeneous group of disorders involving sudden, focal interruption of cerebral blood flow that causes neurologic deficit. Strokes can be Ischemic (80%), typically resulting... read more , blindness Acute Vision Loss Loss of vision is usually considered acute if it develops within a few minutes to a couple of days. It may affect one or both eyes and all or part of a visual field. Patients with small visual... read more , and pituitary insufficiency Selective Pituitary Hormone Deficiencies Selective deficiencies of pituitary hormones may represent an early stage in the development of more generalized hypopituitarism. Patients must be observed for signs of other pituitary hormone... read more .
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, which may be associated with Horner syndrome Horner Syndrome Horner syndrome is ptosis, miosis, and anhidrosis due to dysfunction of cervical sympathetic output. (See also Overview of the Autonomic Nervous System.) Horner syndrome results when the cervical... read more ), 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 , 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 . Features that distinguish cavernous sinus thrombosis from orbital cellulitis include cranial nerve dysfunction, bilateral eye involvement, and mental status changes.
Diagnosis is based on neuroimaging. MRI is the better study, but CT is also helpful. Contrast-enhanced MR venogram (MRV) and CT venogram are more sensitive than either CT or MRI. Useful adjunct testing may include blood cultures and lumbar puncture Lumbar Puncture (Spinal Tap) Lumbar puncture is used to do the following: Evaluate intracranial pressure and cerebrospinal fluid (CSF) composition (see table Cerebrospinal Fluid Abnormalities in Various Disorders) Therapeutically... read more .
Prognosis for Cavernous Sinus Thrombosis
Mortality in the antibiotic era is about 15 to 20%. An additional 40% develop serious sequelae (eg, ophthalmoplegia, blindness, stroke, pituitary insufficiency), which may be permanent.
Treatment of Cavernous Sinus Thrombosis
IV high-dose antibiotics
Initial antibiotics for patients with cavernous sinus thrombosis include nafcillin or oxacillin 1 to 2 g every 4 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 , 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; unfractionated and low-molecular-weight heparin have been used in patients without contraindications, but evidence establishing their efficacy will require further study.
The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
Plewa MC, Tadi P, Gupta M: Cavernous sinus thrombosis. StatPearls Publishing, Treasure Island, 2020.