Cerebral Venous Thrombosis


Cerebral Venous Thrombosis, Thrombosis of Cerebral Vein, Thrombophlebitis of Cerebral Vein, Cerebral Vein Thrombophlebitis, Cerebral Infarction due to Cerebral Venous Thrombosis, Lateral Sinus Thrombosis, Transverse Sinus Thrombosis, Superior Sagittal Sinus Thrombosis, Sagittal Sinus Thrombosis ( C0338575), Sigmoid Sinus Thrombosis, Deep Venous Cerebral Thrombosis, Great Cerebral Vein Thrombosis, Cortical Vein Thrombosis, Superficial Cerebral Vein Thrombosis, Cerebral Sinus Thrombosis

  • Epidemiology
  1. Accounts for 0.5 to 1% of all Cerebrovascular Accidents
  2. Female gender in two thirds of cases
  3. Younger patients (mean age 33 years old)
  • Pathophysiology
  1. See Cerebral Sinus
  2. As with other Venous Thromboembolism, virchow's triad applies to pathogenesis (stasis, vessel wall, Coagulopathy)
  3. Venous obstruction causes increased venous pressure and decreased capillary perfusion
    1. Initial compensation with venous dilation including collateral veins
    2. Progresses to vasogenic edema and decreased Cerebral Perfusion Pressure
    3. Cerebrospinal fluid absorption may also be blocked, increasing Intracranial Pressure
  4. Images
    1. cnsVenousSinus.jpg
  • Risk Factors
  1. Hormonal
    1. Oral Contraceptives
    2. Hormone Replacement Therapy
    3. Pregnancy or Postpartum State (up to 6 weeks after delivery)
  2. Hypercoagulable Conditions or Stasis
    1. Malignancy (esp. Hematologic Malignancy, myeloproliferative disorder)
    2. Inflammatory Conditions (e.g. Systemic Lupus Erythematosus, Inflammatory Bowel Disease, Behcet's Disease)
    3. Thyroid Disease
    4. Antiphospholipid Antibody Syndrome
    5. Hyperhomocysteinaemia (MTHFR gene mutation)
    6. Dehydration
  3. Inflammatory or Structural Conditions
    1. Head and Neck Infections
    2. Central Nervous System Infections
    3. Recent neurosurgery
    4. Closed Head Injury
    5. Dural AV Fistula
    6. Cytotoxic drugs
  • Precautions
  1. Early diagnosis is key to good prognosis
  2. Frequently missed diagnosis
    1. Mimics other acute neurologic conditions
    2. Requires specific testing in most cases (venogram)
  1. Findings are specific to venous sinus involved
  2. Headache (90% of cases, and only symptom in 25% of cases)
    1. New or different Headache
    2. Acute to insidious onset progressive over hours to days
    3. Provoked when Increased Intracranial Pressure (e.g. valsalva, coughing)
  3. Increased Intracranial Pressure
    1. Papilledema
    2. Visual changes
    3. Nausea or Vomiting
  4. Focal Findings
    1. Motor deficits
    2. Seizure
  5. Encephalopathy (esp. deep sinus involvement)
    1. Altered Mental Status
  • Findings
  • Transverse Sinus Thrombosis
  1. Accounts for 44 to 73% of cases
  2. Isolated, noninfectious unilateral thrombosis
    1. Symptoms may be mild (e.g. Headache) if no infarction
    2. Seizures
    3. Contralateral Hemiparesis, hyperreflexia, or spasticity (pyramidal symptoms) may be present
  3. Left Transverse Sinus (with venous infarction, occluded vein of Labbe)
    1. Aphasia
  4. Contiguous Sinus extension (e.g. Superior Sagittal Sinus)
    1. Increased Intracranial Pressure (Intracranial Hypertension)
    2. Altered Level of Consciousness
    3. Cranial Nerve Palsy (CN 9-12)
  5. Cerebral Vein Extension
    1. Headache
    2. Vomiting
    3. Ataxia
    4. Limb Incoordination
  • Findings
  • Superior Sagittal Sinus Thrombosis
  1. Accounts for 39-62% of cases
  2. Increased Intracranial Pressure (Intracranial Hypertension)
    1. Isolated in many cases
  3. Focal venous infarction related symptoms
    1. Headache
    2. Blurred Vision, Vision Loss or Hemianopsia (Visual Field deficit)
    3. Nausea or Vomiting
    4. Cranial Nerve Palsy
    5. Aphasia
    6. Hemiparesis or hemi-sensory loss
    7. Seizures
  • Findings
  • Sigmoid Sinus Thrombosis
  1. Accounts for 40-47% of cases
  2. Mastoid region pain
  3. Cranial Nerve Deficit (CBN 6-8)
  • Findings
  • Deep Venous Cerebral Thrombosis (e.g. Great Cerebral Vein of Galen)
  1. Accounts for 10-11% of cases
  2. Altered Mental Status (encephalopathy to coma)
  3. Motor deficits
    1. Fluctuating or alternating paresis (or bilateral)
  • Findings
  • Cortical Vein Thrombosis (Superficial Cerebral Vein Thrombosis)
  1. Accounts for 3-17% of cases
  2. Thrombosis involving superficial veins (superficial middle and anastomotic cerebral veins)
  3. Seizures
  4. Focal neurologic deficits depending on distribution of thrombosis
  1. See Cavernous Sinus Thrombosis
  2. Accounts for 1-2% of cases
  3. Headache
  4. Eye Pain
  5. Chemosis
  6. Proptosis
  7. Cranial Nerve Palsy (CN 3, 4, and 6, as well as opthalmic branch CN 5)
  8. Fever (if septic Thrombophlebitis)
  • Imaging
  1. Non-Contrast Head CT
    1. Low Test Sensitivity for Cerebral Venous Thrombosis (~33%)
    2. Findings consistent with Cerebral Venous Thrombosis
      1. Delta Sign
        1. Posterior Superior Sagittal Sinus hyperdensity
      2. Venous Cerebral Infarction
        1. Infarct spans more than one arterial perfusion regions
      3. Diffuse cerebral edema
      4. Hydrocephalus
      5. Subarachnoid Hemorrhage (secondary)
  2. CT Venogram (with CT Head)
    1. Gold standard study for venous cerebral thrombosis
    2. Similar efficacy to MRV except in Altered Level of Consciousness or encephalopathy
  3. Magnetic Resonance Venogram (MRI/MRV)
    1. As with CT Venogram, gold standard for Cerebral Venous Thrombosis diagnosis
    2. MRV is preferred over CT venogram for patients with Altered Level of Consciousness or encephalopathy
      1. Suggests possible deep cerebral vein thrombosis (better visualized on MRV)
    3. General Findings
      1. DWI hyperintense
      2. Cerebral venous wall enhancement
      3. Thrombosed sinuses with decreased or absent flow
    4. Findings vary by timing from onset
      1. Week 1: T1W/T2W isointense to hypointense
      2. Week 2: T1W/T2W hyperintense
  • Management
  1. Consult Neurosurgery and Stroke Neurology
  2. Initiate Low Molecular Heparin (e.g. Lovenox) which is preferred over Unfractionated Heparin
    1. Initiate Anticoagulation with Warfarin with INR target 2-3 for 3-12 months
      1. Limited evidence for DOACs in CVT as of 2020, and therefore Warfarin is preferred
    2. First episode of CVT: 3-6 months (6-12 months if no known risk factor)
    3. Continue Anticoagulation lifelong for recurrent CVT
  3. Endovascular intervention considered in decompensating or refractory cases
  4. Manage Increased Intracranial Pressure
    1. Acute monitoring by neurosurgery if risk of Increased Intracranial Pressure
  5. Manage Seizures
    1. Antiepileptic drugs are indicated for clinical evidence of Seizures and are continued for >=1 year
  • Prognosis
  1. Recurrent Venous Thrombosis risk off of Anticoagulation
    1. Recurrent Cerebral Venous Thrombosis: 2-7% per year
    2. Recurrent Venous Thromboembolism (e.g. DVT, PE): 4-7% per year
  • References
  1. Marcolini and Swaminathan in Herbert (2021) EM:Rap 21(2): 5-7
  2. Ulivi (2020) Pract Neurol 20:356-67 [PubMed]