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Neurology

Cerebral venous sinus thrombosis

Cerebral venous sinus thrombosis is thrombosis of a dural venous sinus or cerebral vein that obstructs venous drainage, causing raised intracranial pressure, venous infarction, haemorrhage, seizures and focal or diffuse neurological dysfunction.

In a nutshell

Cerebral venous sinus thrombosis is thrombosis of the cerebral venous sinuses or veins causing raised intracranial pressure and venous infarction, which may be haemorrhagic. Headache is common and may be isolated; seizures, focal deficits, visual symptoms and encephalopathy are important clues. Confirm with CT or MR venography and give full-dose anticoagulation even when secondary haemorrhage is present.

Classic presentation

A pregnant or postpartum patient, or a person taking combined hormonal contraception, develops a persistent headache followed by a focal seizure; imaging shows a haemorrhagic lesion that does not fit an arterial territory and venography confirms a sinus filling defect.

Key points

  • Headache may be the only symptom; seizures, papilloedema, visual loss, focal deficits and encephalopathy are important presentations.
  • Suspected cerebral venous thrombosis requires CT or MRI with venography; a normal non-contrast CT does not exclude it.
  • Venous infarction often crosses arterial territories and may haemorrhage.
  • Give full-dose anticoagulation even with secondary cerebral haemorrhage; NICE specifies initial heparin followed by warfarin with INR 2 to 3.
  • Low-molecular-weight heparin is generally preferred acutely; use unfractionated heparin when renal failure, invasive treatment or rapid reversal makes it preferable.
  • Pregnancy, puerperium, combined oestrogen contraception, infection, dehydration, malignancy and thrombophilia are important contexts.
  • Do not use a normal D-dimer or negative thrombophilia screen to override clinical suspicion or replace venography.
  • Impending herniation, threatened vision, status epilepticus and neurological deterioration require urgent specialist escalation.

First-line investigation

Urgent brain imaging with CT or MRI including CT or MR venography; do not rely on plain CT or D-dimer alone.

Management

Recognise the neurological emergency

  • Admit for specialist stroke or neurovascular care; escalate reduced consciousness, status epilepticus, threatened vision, hydrocephalus, mass effect or impending herniation immediately.1,2

Confirm with venography and anticoagulate

  • Use CT or MR venography and start full-dose heparin even when secondary haemorrhage is present; low-molecular-weight heparin is usually preferred unless unfractionated heparin is needed.1,2,3,8

Continue anticoagulation and treat the cause

  • Continue with specialist-directed oral anticoagulation for at least 3 months, following the NICE/RCP heparin-to-warfarin pathway, while treating infection and addressing pregnancy, contraception, malignancy and other provoking factors.1,2,8

Protect brain function and vision

  • Treat seizures, monitor vision and raised intracranial pressure, involve neuro-ophthalmology and neurosurgery when needed, and use specialist-directed decompression for impending herniation.3,7,2

Reserve rescue intervention for deterioration

  • Endovascular thrombolysis or thrombectomy is not routine first-line care; discuss selected deterioration despite appropriate anticoagulation with a specialist neurointerventional centre.3

Follow recovery, recurrence, safety and driving

  • Review anticoagulation, headache, seizures, vision, cognition, mood, rehabilitation, pregnancy or contraception plans and recurrent VTE symptoms; give written red-flag and DVLA advice.2,5,8

Exam traps

  • Haemorrhagic venous infarction is not, by itself, a contraindication to therapeutic anticoagulation.
  • A normal non-contrast CT does not exclude cerebral venous thrombosis; venography is required when suspicion remains.
  • A normal D-dimer does not safely exclude cerebral venous thrombosis, especially with isolated headache or prolonged symptoms.
  • Do not confuse venous infarction with an arterial-territory stroke, and do not perform lumbar puncture before excluding mass effect or obstructive hydrocephalus.
  • Do not routinely give antiseizure medication to prevent a first seizure, corticosteroids for cerebral venous thrombosis, or endovascular therapy as first-line treatment.
  • Stop combined oestrogen-containing contraception and give current DVLA advice after cerebral venous thrombosis or seizure.

Illustrations

Empty delta sign in cerebral venous sinus thrombosisContrast-enhanced axial CT showing a triangular central filling defect in the superior sagittal sinus, the empty delta sign of cerebral venous sinus thrombosis.Heather, Wikimedia Commons · Public domain
Haemorrhagic venous infarction on CTAxial non-contrast CT showing an arrowed left temporal haemorrhagic focus with extensive surrounding hypodense oedema, consistent with haemorrhagic venous infarction in cerebral venous sinus thrombosis.Prabasara HKDK et al., Cureus 2025, CC-BY-4.0 · CC-BY-4.0

Key sources

  1. NICE NG128, Stroke and transient ischaemic attack in over 16s: diagnosis and initial management (Current NICE recommendation 1.4.13: offer full-dose anticoagulation, initially full-dose heparin then warfarin with INR 2 to 3, for cerebral venous sinus thrombosis including secondary cerebral haemorrhage unless comorbidities preclude it)
  2. National Clinical Guideline for Stroke for the UK and Ireland, 2023: acute care, section 3.9 cerebral venous thrombosis (Current 2023 UK and Ireland stroke guideline: investigate suspected cerebral venous thrombosis with CT or MRI including venography and use full-dose anticoagulation for at least 3 months, initially heparin then warfarin INR 2 to 3)Updated 4 May 2023
  3. European Stroke Organisation guideline for the diagnosis and treatment of cerebral venous thrombosis, endorsed by the European Academy of Neurology (International specialist guideline used where the UK sources do not cover detailed CVT questions: LMWH preference, selective D-dimer and thrombophilia testing, seizures, raised intracranial pressure, decompressive surgery, pregnancy and rescue endovascular therapy)Updated 1 Sept 2017
  4. NICE NG12, Suspected cancer: recognition and referral (Current NICE neurological referral pathway used for progressive or unexplained central neurological symptoms and to support urgent imaging decisions)
  5. GOV.UK, Neurological disorders: assessing fitness to drive (DVLA guidance updated 7 November 2025; cerebral venous thrombosis, residual neurological deficit and seizure rules affect driving and notification)Updated 7 Nov 2025
  6. NICE NG158, Venous thromboembolic diseases: diagnosis, management and thrombophilia testing (Current NICE venous-thromboembolism and thrombophilia-testing principles used for targeted cause assessment and anticoagulation follow-up)
  7. Idiopathic intracranial hypertension: consensus guidelines on management (UK multidisciplinary consensus guidance used for specialist visual assessment and cautious interpretation of lumbar puncture, acetazolamide and vision-preserving interventions in raised intracranial pressure; CVT-specific decisions remain governed by CVT guidance)Updated 14 Jun 2018
  8. BNF, current prescribing information for anticoagulation, antiseizure medicines and intracranial-pressure treatment (Current UK prescribing source for heparins, warfarin, antiseizure medicines and acetazolamide; direct access was restricted and the available browser session was unavailable, so unsupported drug doses were omitted)

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.