The patient complaint of “headache” often causes me to have a headache. There are so many things to ponder. We have previously covered some important conditions to consider when evaluating headache (ex, AVM, RMSF, Meningitis, Post-LP, Moyamoya, Migraine, Pseudotumor, and Pheochromocytoma). Many of these are rare and require our dedicated vigilance to ascertain the clues that point toward the diagnosis. Another entity that requires our super-sleuthing skills is Cerebral Venous Thrombosis (CVT).

CVT: Basics

• CVT is rare, but has significant consequences [Saposnik, 2011]
  • Incidence is estimated to be ~0.6 per 100,000 children per year
  • Thrombosis of the venous system results in venous congestion and outflow obstruction creating increased capillary hydrostatic pressure. [Dlamini, 2010]
    • Increased hydrostatic pressure can lead to cerebral edema.
    • If pressures become high enough, can also compromise arterial flow and lead to ischemia.
    • Majority of infarcts become hemorrhagic.
  • Mortality is <10%, but persistent neurologic deficits can be seen in up to 79% of patients. [Dlamini, 2010]
• Can affect all ages
  • ~40% of pediatric patients who have CVT are neonates
    • Increased thrombotic tendency in neonates. [Saposnik, 2011]
    • Mechanical forces on neonates head also increase risk. [Saposnik, 2011]
  • Non-neonates present similarly to adults [Star, 2013; deVeber, 2001]

CVT: Presentation

• Clinical presentation is often subtle and not specific (once again, our job is challenging). [Dlamini, 2010]
• Presentation varies with age:
  •  Neonates
    • Seizures
    • Lethargy
    • Respiratory Failure
    • Altered Mental State and Coma
  • Older infants and children present similarly to adults. [Star, 2013; deVeber, 2001]
    • Headache
      • Seen in 89% of cases
      • May even be associated with idiopathic intracranial hypertension.
    • Nausea / vomiting
    • Focal neurologic deficit / abnormality
      • Seizures
      • Hemiparesis
      • Papilledema
      • Ataxia
      • Speech or visual impairment
      • CN VI Palsy

• Presentation can also vary based on location of thrombus. [Star, 2013]
  • Cerebral Venous Sinuses
    • Increased intracranial pressure
    • Headache, impaired vision, papilledema
  • Smaller Cerebral Veins
    • Focal venous ischemia
    • Focal neurologic deficits

CVT: Risk Factors

• Risk factors often vary with age:
  • Neonates – perinatal complications, hypoxic encephalopathy, are most common
  • Younger children – head and neck infections are most common
  • Older children – chronic diseases are most common
• Often CVT risk is multifactorial. [Dlamini, 2010; Heller, 2003]

• Local infection, injury, or abnormality
  • Head and neck infections (ex, otitis media, mastoiditis, sinusitis)
  • Local trauma
• Systemic Illness
  • Dehydration
  • Sepsis
  • Cardiac Disease
  • Connective Tissue Disorders
  • Live Disease
  • Nephrotic Syndrome
  • Behcet’s Disease
  • Cancer
  • Anemia
    • Iron deficiency anemia is associated with CVT
    • Hemoglobinopathies (ex, Sickle Cell Disease)
• Pro-thrombotic Disorders (noted in 12-50%)
  • Anticardiolipin antibody
  • Protein C and Protein S deficiencies
  • Factor V Leiden
  • Lupus Anticoagulant
  • Homocystinuria
• Pro-coagulant Medications
  • Oral Contraceptive Pills
  • Asparaginase

CVT: Evaluation and Management

• Imaging modality:
  • MRI with Venography is the modality of choice.
    • Occasionally, contrast is required given that thrombus can be difficult to distinguish from a hypoplastic sinus vein.
  • CT Venogram can also be used and is as effective as MRV, but has radiation (obviously).

• Treatment: [Saposnik, 2011]
  • Rehydrate 
  • Treat associated infections
  • Treat seizures 
  • Treat increased intracranial pressure
  • Start anticoagulant
    • Treatment with anticoagulant has been deemed safe and effective. [Moharir, 2010]
      • Low Molecular Weight Heparin or Unfractionated Heparin are appropriate.
      • Oral Vitamin K Antagonist or LMWH will be continued for 3-6 months.
    • Recommended even in those who have hemorrhage noted at time of diagnosis. [Star, 2013; Saposnik, 2011]
    • 31% of children who don’t receive anticoagulation have propagation of thrombus.

Moral of the Morsel

• We see many patients with headaches… not all of them have benign causes. Be Vigilant!
  • Check for papilledema in cases presenting with headache.
  • Look for potential risk factors of CVT.
• Thinking a patient has idiopathic intracranial hypertension (i.e., pseudotumor), check MRV when you get the MRI… there may be an associated Cerebral Venous Thrombosis!

References