Today, I review, link to, and excerpt from The Cribsiders‘ #114: Cerebral Sinus Venous Thrombosis – A Deep Conversation About Thrombosis in the Brain.*

*Kelly JM, Beslow LA, Masur S, Chiu C, Berk J. “Cerebral Sinus Venous Thrombosis”. The Cribsiders Pediatric Podcast. https:/www.thecribsiders.com/ July 17, 2024.

All that follows  is from the above resource.

Summary:

A cerebral sinus venous thrombosis (CSVT) is a blood clot in the venous system of the brain that can result in headache, emesis, double vision, and even coma. Listen to this episode to hear more from Dr. Lauren Beslow about the key risk factors for CSVT, important findings on physical exam that suggest CSVT, and the best imaging to diagnose a CSVT in your patient!

Cerebral Sinus Venous Thrombosis Pearls

1. CSVT is a known complication of dehydration, acute otitis media, and mastoiditis in pediatric patients.
2. A careful history can reveal key risk factors for CSVT such as malignancy, inflammatory bowel disease, and oral contraceptive use.
3. Consider neuroimaging in children presenting with a new onset headache, a new headache type, persistent headache, or any headache red flags.
4. The most sensitive test for CSVT is MRI/MRV with and without contrast, but if unavailable, a good first imaging test is a non-contrast head CT.

Cerebral Sinus Venous Thrombosis Notes

Terms

• Cerebral sinus venous thrombosis (CSVT), sinovenous thrombosis, or cerebral venous thrombosis (CVT) are all similar terms and often used interchangeably.

CSVT Definition

• A blood clot in the venous system of the sinuses or large veins that drain the brain
• Prevents blood from draining out of the brain and increases intracranial pressure
• Can be complicated by hemorrhage and venous ischemia

Red Flags on History 

• Headache in the setting of the recent otitis or mastoiditis is concerning for CSVT (Saposnik, et al. 2024)
• Vision changes, double vision, headache waking up a patient at night, vomiting, new headache for the child, and unremitting headache are red flags that should make you consider neuroimaging.

Vision Changes in CSVT

• Can be difficult to figure out what the child is reporting on history (double vision vs blurry vision)
• Double vision
  • Can be due to a CN6 palsy caused by increased intracranial pressure
  • Test with extra ocular movements (be sure to bury the sclera on lateral gaze in each direction)
  • Young children may hold their head to the side (reduces the double vision), and you have to pick up on this on physical exam
• Blurry vision
  • If a child has papilledema from CSVT, they also could have decreased visual acuity
  • Test with Near Card for visual acuity
    • Test each eye separately
    • Can use finger puppets for young children (the child should reorient and look at what’s new coming into the vision, and if they persistently aren’t looking, then there might be a visual acuity problem)
• Consider neuro-ophthalmology evaluation for papilledema in patients with diagnosed CVST (Saposnik, et al. 2024)

Risk factors for CSVT

• Dehydration (especially in neonates and babies), head and neck infections (e.g., otitis media, mastoiditis, meningitis), prothrombotic states (e.g., antithrombin three deficiency), high output chylothorax, leukemia, nephrotic syndrome, iron deficiency anemia, inflammatory bowel disease, rheumatological diseases (e.g., Behçet’s disease), sickle cell disease, pregnancy, medications (e.g., oral contraceptive pills with estrogen, asparaginase), posttraumatic, transplacental transfer of maternal antiphospholipid (less common)(Saposnik, et al. 2024)
• We don’t fully understand why some children have a CSVT, but factors such as inflammation, hemoconcentration, slow flow, and direct compression of cerebral veins contribute to thrombus formation

Anatomy

• In the cerebral venous system a CSVT can be located in the dural venous sinus/deep venous sinuses/great venous sinuses (e.g., superior sagittal sinus, inferior sagittal sinus, transverse sinus, and sigmoid sinus)
  • May also see an associated venous clot in the smaller cerebral veins (cortical veins or medullary veins)

Physical Exam

• Many children may have completely normal examinations
• Check for meningismus, papilledema, visual loss, CN6 palsy and lateral eye movements, head tilt
• Focal neuro deficits
  • If CSVT is complicated by hemorrhage/venous ischemia it can be difficult to differentiate by examination from someone who has a primary hemorrhage or an arterial ischemic stroke
• Mental status changes, coma, seizures can also be present

Imaging Modalities 

• When concerned for CSVT, Dr. Beslow recommends discussing the best imaging with your institutional neuroradiologists
• Noncontrast head CT
  • A good first-line test with ~80% sensitivity  (Ferriero et al., 2019)
  • Fast!
  • If negative, don’t rule out CSVT if you have clinical concern
• CT Venogram (CTV) – (can be paired with CT)
  • Pros: better evaluation of the dural sinuses
  • Cons: More radiation than non-contrast head CT alone and has the exposure to contrast
• Most sensitive imaging: MRI with and without contrast with MR venogram (MRV)
  • No radiation, but may require sedation!
  • Can see parenchyma of the brain, better evaluation of hemorrhage and infection, may help with surgical planning if needed
  • If you can only get one MRI sequence: obtain contrast enhanced MRI (expert opinion)
• Rapid head MRI or fast MRI: not ideal for diagnosing CSVT (rapid sequence MRIs are typically looking for arterial ischemic stroke and don’t include contrast)

Treatment of CSVT

• Hydration (Saposnik, et al. 2024)Dr. Below recommends 1.5x maintenance IVF if possible for the patient
• Remove provoking factors (e.g., treat iron deficiency anemia or stop oral contraceptive)
• Treat infectious trigger (e.g., starting antibiotics for mastoiditis or performing surgical mastoidectomy)

 

• Anticoagulation
  • Many children (not all) receive anticoagulation (Saposnik, et al. 2024)
    • For example, Dr. Beslow notes that some centers might consider not anticoagulating a patient with a non-occlusive thrombus in the setting of mastoiditis
    • Heparin infusion or low weight molecular heparin (enoxaparin) are most commonly used
      • May be able to transition some children to direct oral anticoagulants (DOACs) which are easier than enoxaparin injection for some children (expert opinion)
    • In adults, there is good data to anticoagulate CSVT even if associated hemorrhage. This data is extrapolated to pediatrics.
  • Duration of anticoagulation
    • • If provoked, 3-6 months (Saposnik, et al. 2024)
      • Case to case variability (e.g., a patient with a known thrombophilia may be on anticoagulation for life)
      • May repeat MRI to evaluate for recanalization to determine full treatment duration
• Thrombectomy is rarely done
  • • • Reserve for a child who is worsening despite anticoagulation or has clear contraindications to anticoagulation (Saposnik, et al. 2024

Disposition 

• Dr. Beslow recommends to initially admit patients to the pediatric intensive care unit
  • Concern for propagation of clot and need for frequent neuro checks
  • Risk of hemorrhage (especially if starting anticoagulation) and hemorrhagic transformation of venous infarction
  • Once stable, can transfer out of the intensive care unit

Other Stuff

Citations

1. Management of Stroke in Neonates and Children: A Scientific Statement From the American Heart Association/American Stroke Association (Ferriero et al., 2019)
2. Diagnosis and management of cerebral venous thrombosis: a statement for healthcare professionals from the American Heart Association/American Stroke Association (Saposnik, et al. 2024)