Thursday, 18 November 2010

MRCP revision battle 53.3: Intracranial venous thrombosis

The presentation of intracranial venous thrombosis depends on which venous sinus is affected.

All locations of intracranial venous thrombosis can cause headache.

Isolated sagittal sinus thrombosis (=nearly half of intracranial venous thrombosis) or lateral sinus thrombosis present with:
  • headache
  • vomiting
  • seizures
  • papilloedema
  • potentially focal neurological signs

Cavernous sinus thrombosis can cause:
  • headache
  • oedematous eyelids
  • proptosis
  • painful eye movements/opthalmoplegia
Cavernous sinus thrombosis is often associated with infection spreading from the face or paranasal sinuses.
Remember: cavernous sinus contains CN III, IV, V1, V2 and VI, plus the internal carotid artery.

Sigmoid sinus thrombosis:
  • headache
  • cerebellar signs

Inferior petrosal sinus thrombosis:
  • 5th and 6th nerve palsies

Risk factors for developing intracranial venous thrombosis include:
  • pregnancy
  • head injury
  • recent LP
  • oral contraceptive pill

Investigation is:
  • MRI/CT
    • CT may show 'absent delta sign' which implies a filling defect and therefore a thrombosis
  • ?MRV

Management is by specialists, ?heparin

On to the more familiar topic of infective endocarditis...