What is the recommended treatment for suspected cavernous sinus thrombosis?

Management of Suspected Cavernous Sinus Thrombosis

For suspected cavernous sinus thrombosis, immediate anticoagulation with intravenous heparin or subcutaneous low molecular weight heparin should be initiated, even if intracranial hemorrhage is present. 1

Diagnostic Approach

Imaging

1. First-line imaging:

   • Contrast-enhanced MRI with MR venography is the gold standard 1
   • CT venography with IV contrast is an acceptable alternative when MRI is unavailable 2, 1

2. Key imaging findings:

   • MRI: Absence of flow void, altered signal intensity in cavernous sinus, T2 hypointensity suggesting thrombus 1
   • CT: Hyperdensity of cavernous sinus on non-contrast CT, "empty delta" sign on contrast-enhanced images 1
   • Note: Non-contrast CT alone misses up to 70% of cerebral venous thrombosis cases 1

Laboratory Evaluation

• Complete blood count to assess for thrombocytopenia
• Coagulation studies
• Blood cultures to identify causative organisms 3

Treatment Algorithm

1. Anticoagulation (Start Immediately)

• Initial therapy: IV unfractionated heparin or subcutaneous LMWH 2, 1
• Duration: 3-12 months depending on underlying etiology 1
• Long-term: Transition to vitamin K antagonists (target INR 2.5) after acute phase 1

2. Antimicrobial Therapy

• Broad-spectrum antibiotics targeting common causative organisms:
  • Staphylococcus aureus
  • Streptococcal species
  • Oral anaerobes
  • Gram-negative bacilli 1, 3
• Common regimen: Ceftriaxone and metronidazole IV 3
• Consider antifungal coverage (voriconazole or amphotericin B) if invasive fungal sinusitis is suspected 1

3. Surgical Intervention

• Indicated for:
  • Drainage of identified source of infection (e.g., sphenoid sinusitis) 3, 4
  • Severe mass effect requiring decompression 1
  • Urgent intervention for infectious sources 1, 3

4. Adjunctive Therapies

• Corticosteroids: Consider if significant inflammation or edema is present 1, 5
• Management of intracranial hypertension if present 1

Monitoring and Follow-up

• Close neurological monitoring during acute phase 1
• Follow-up imaging with MRV or CTV at 3-6 months to assess recanalization 1
• Earlier follow-up imaging if symptoms persist or worsen despite treatment 1

Potential Complications and Pitfalls

• Delayed diagnosis: Can lead to increased morbidity and mortality 1, 4
• Inadequate source control: May worsen outcomes despite appropriate anticoagulation 1
• Overlooking fungal causes: Particularly in immunocompromised patients 1
• Misinterpretation of normal variants: Asymmetrical lateral sinuses (present in 49% of normal population) can be mistaken for thrombosis 1
• Potential sequelae: Lemierre syndrome, ophthalmic complaints, and cranial nerve paralysis 3

Special Considerations

• Patients may present with somnolence or confusion without obvious focal neurological deficits, especially in elderly patients 1
• Venous infarcts may cross arterial territories and have cortical sparing 1
• While anticoagulation carries a theoretical risk of hemorrhage, retrospective reviews indicate that hemorrhage caused by anticoagulation is rare, and early adjunctive anticoagulation is beneficial 6

Warning Signs for Deterioration

• Worsening neurological status despite treatment requires repeat imaging to assess for progression 1
• Consider endovascular therapy or decompressive hemicraniectomy in cases of neurological deterioration 1