What is the management for a superficial thrombus in a cerebral venous sinus?

Management of Superficial Thrombosis in Cerebral Venous Sinus

Immediate anticoagulation therapy should be initiated for superficial thrombosis in cerebral venous sinuses, even in the presence of hemorrhagic changes, as the primary treatment approach. 1, 2

Diagnosis

• MRI with MR venography (MRV) is the gold standard for diagnosis of cerebral venous thrombosis (CVT) 2
• CT with CT venography (CTV) is an acceptable alternative when MRI is contraindicated or not readily available 1, 2
• Imaging findings may include:
  • "Empty delta sign" on contrast-enhanced CT
  • Absence of flow void with altered signal intensity in the dural sinus on MRI
  • Hyperintense vein sign on T2-weighted imaging 1

Initial Management

Anticoagulation Therapy

• Begin anticoagulation immediately upon diagnosis, even if hemorrhagic infarction is present 1, 2
• Options include:
  • Intravenous unfractionated heparin (UFH): Initial bolus of 3000 U followed by continuous infusion adjusted to achieve activated partial thromboplastin time twice the pretreatment value 1
  • Subcutaneous low molecular weight heparin (LMWH): Dosed based on body weight (180 anti-factor Xa units per kilogram daily in 2 divided doses) 1
  • LMWH is preferred over UFH in pregnancy-associated cases 2

Management of Complications

• For increased intracranial pressure: Consider antiedematous agents (mannitol or hypertonic saline) 2
• For seizures: Initiate anticonvulsant therapy (40% of patients develop seizures) 2
• For significant mass effect or neurological deterioration:
  • Consider decompressive hemicraniectomy 1
  • Endovascular therapy may be considered in patients with contraindications to anticoagulation or failure of initial anticoagulation therapy 1

Long-term Management

Duration of Anticoagulation

• Transition to oral anticoagulation after initial treatment with heparin/LMWH
• Duration depends on underlying etiology:
  • 3 months for transient risk factors
  • 6-12 months for idiopathic thrombosis or mild thrombophilia
  • Lifelong for high-risk thrombophilia, recurrent thrombotic events, or antiphospholipid syndrome 1, 2

Follow-up Imaging

• Follow-up CTV or MRV at 3-6 months after diagnosis to assess for recanalization of the occluded cortical vein/sinuses 1, 2
• Earlier imaging may be warranted for patients with persistent or evolving symptoms despite medical treatment 2

Prognosis and Monitoring

• Despite modern treatment, CVT carries significant morbidity, with less than half of patients recovering completely 2
• Poor prognostic factors include:
  • Female gender
  • Sudden onset
  • Posterior 1/3 occlusion of the superior sagittal sinus
  • Extension of thrombosis from superior sagittal sinus into cortical veins 2

Special Considerations

• Intracranial hemorrhage that occurs as a consequence of CVT is not a contraindication for anticoagulation 1
• Non-heparin based anticoagulants should be considered if there is concern for heparin-induced thrombocytopenia 2
• Thrombolytic therapy may be considered in specific circumstances such as severe symptoms with massive thrombosis or recent thrombus (less than 10 days old) with low bleeding risk 2

Common Pitfalls

• Delays in diagnosis are common (median delay from symptom onset to diagnosis is 7 days) 1
• CVT may be confused with other conditions like arterial stroke, idiopathic intracranial hypertension, or meningitis 1
• D-dimer has limited utility in diagnosis of CVT due to poor specificity, though it may have a role in exclusion of the diagnosis when negative 1
• Isolated cortical venous thrombosis is identified much less frequently than sinus thrombosis and may be missed on initial imaging 1

Management in a stroke unit is reasonable for initial care to optimize outcomes and minimize complications 1.