DESCRIPTION

• Cavernous sinus syndrome comprises disease processes that localize to the cavernous sinus—a venous plexus that drains the face, mouth, tonsils, pharynx, nasal cavity, paranasal sinuses, orbit, middle ear, and parts of the cerebral cortex.
• Small lesions in this region may produce dramatic neurologic signs.

EPIDEMIOLOGY

Cavernous sinus syndrome is a rare but serious condition.

PATHOPHYSIOLOGY

• The cavernous sinus is located lateral to the pituitary gland and sella turcica, superior to the sphenoid sinus, and inferior to the optic chiasm.
• Within the cavernous sinus are the carotid artery, the pericarotid sympathetic fibers, and the abducens nerve (VI); within its lateral wall are the oculomotor nerve (III), the trochlear nerve (IV), and the ophthalmic and maxillary divisions of the trigeminal nerve (V₁, V₂).
• Cavernous sinus syndrome is typically caused by septic or aseptic sinus thrombosis, neoplasm, or trauma. Acute obstruction by mass or thrombosis may progress rapidly if not diagnosed and treated quickly.

ETIOLOGY

• Infectious agents include Staphylococcus aureus, Streptococcus pneumoniae, gram-negative rods, and anaerobes; mucormycosis and Aspergillus in immunocompromised patients
• Aseptic venous thrombosis has been associated with sickle cell anemia, trauma, dehydration, vasculitis, pregnancy, oral contraceptive use, congenital heart disease, inflammatory bowel disease, and hypercoagulable states.
• Neoplasms involving the cavernous sinus include pituitary adenomas, meningiomas, trigeminal schwannomas, craniopharyngiomas, lymphomas, neuromas, chordomas, chondrosarcomas, rhabdomyosarcomas, nasopharyngeal carcinomas, and very rarely, teratomas. Neoplasms may present with diplopia, visual field deficits, headache, or isolated cranial nerve deficits.
• The lateral extension of pituitary neoplasms into the cavernous sinus usually affects the 3rd cranial nerve, with the 4th and 6th nerves less commonly involved. Rupture of a cystic craniopharyngioma may present as acute cavernous sinus syndrome.
• Carotid-cavernous fistulas, often with a more chronic course, are direct high-flow shunts between the internal carotid artery and the cavernous sinus. Most often sequelae of trauma, they may present with a history of ocular motility deficits, arterialization of conjunctival vessels, and a bruit usually heard best over the orbit. Less commonly, rupture of a carotid cavernous aneurysm may lead to fistula formation.
• Nonspecific and idiopathic inflammation of the cavernous sinus, also called idiopathic cavernous sinusitis or Tolosa-Hunt syndrome, has been reported in patients as young as 3 1/2 years. This is a diagnosis of exclusion. However, MRI may show enlargement of the affected cavernous sinus with an adjacent soft tissue mass that resolves after treatment with steroids.