Description

• Thrombosis of a branch of the major intracerebral venous drainage system
• Most commonly infectious
• Spreads from facial, odontogenic, or sinus infection
• Less frequently occurs with hypercoagulable state

• Cavernous sinus – most common:
  • Drainage from superficial venous system
• Superolateral to the sphenoid sinus and surrounds the sella:
  • Cranial nerves (CN) III, IV, V1, and V2 traverse the lateral wall of the sinus
  • CN VI and the internal carotid artery occupy the medial portion of the sinus
• Can also involve transverse sinus and superficial sagittal sinus

Pathophysiology

• Hematogenous spread of facial, otic, or neck infection into venous drainage system
• Contiguous spread directly from infected sinus cavities (sphenoid, ethmoid > frontal)
• Bacterial overgrowth leads to inflammation and coagulation, resulting in thrombosis
• Venous engorgement of cavernous sinus can affect adjacent structures:
  • Ophthalmoplegia from inflammation of CN III, IV, or VI
  • Pupillary fixation from CN III
  • Sensory deficits or paresthesia of forehead or cheek from CN V1 and V2

Etiology

• Septic:
  • Staphylococcus aureus accounts for 70%
  • Streptococcus pneumoniae, gram-negative bacilli, and anaerobes also seen
  • Fungi less common; include Aspergillus and Rhizopus species
• Aseptic:
  • Less common
  • Granulomatous conditions (TB)
  • Inflammatory disorders
  • From mass effect (tumors at base of skull, aneurysms)
• Hypercoagulable states

• Children may present with nonspecific symptoms such as decreased energy, vomiting, fever
• Have high level of suspicion for any child with recent otitis or pharyngitis with worsening symptoms, declining mental status, or signs of increased intracranial pressure (ICP):
  • HTN, bradycardia, lethargy, vomiting, gait instability
• More common in the neonatal period, when diagnosis can be extremely difficult to make