9B. Thrombosis of the intracranial sinuses

Definition and epidemiology

Cerebral venous sinus thrombosis (CVST) or cerebral venous thrombosis (CVT) refers to thrombosis of the cerebral veins or cerebral sinuses in the brain. It can be infectious or non-infectious in origin. Thrombosis of the venous drainage of the brain increases the ICP and it can cause brain ischaemia.

The prognosis is good. 80% recover completely.

Etiology

  • Non-infectious
    • Hypercoagulable state
      • Contraceptives
      • Blood clotting disorders (Leiden mutation, antiphospholipid syndrome)
      • Polycythaemia
      • Cancer
    • Head trauma
    • Iatrogenic after lumbar puncture
  • Infectious (septic cerebral venous sinus thrombosis)
    • Spread from nearby local bacterial or fungal infections
    • Rhinosinusitis
    • Dental infection
    • Acute otitis media, mastoiditis

In many of the cases the patient has an underlying hypercoagulable state.

Clinical features

Symptoms are very variable. They can be acute, subacute, or chronic. Symptoms are non-specific and include headache, increased ICP, focal neurological symptoms, and seizures.

If the thrombosis occurs in the superior sagittal sinus, the patient can develop bilateral frontal infarcts, which can cause hemiparesis or paraparesis.

If the thrombosis occurs in the cavernous sinus, the patient can develop palsy of CN III, CN IV, causing ophthalmoplaegia, pupillary alterations, exophthalmos, etc.

Diagnosis and evaluation

Diagnosis is made with CT or MR venography. It can show the thrombosis, or it can show lesions of ischaemia which do not correspond to a single artery territory. The D-dimer is usually high.

It’s important to screening for blood clotting disorders. If infectious etiology is suspected, CRP and blood culture are important.

Treatment

All patients should receive anticoagulants, especially LMWH initially and VKA for half a year. If a thrombophilia is diagnosed, the patient should be on anticoagulants for life.


Previous page:
9A. Peripheral facial palsy (Bell-paresis)

Next page:
10A. Acute meningitis

Leave a Reply

Your email address will not be published.