Intracranial Hemorrhage

Basics

Description

Intracranial hemorrhage (ICH) is defined as the pathologic accumulation of blood into the epidural, subdural, subarachnoid, intraparenchymal, or intraventricular space within the cranium due to loss of blood vessel integrity or coagulopathy. The term “hemorrhagic stroke” refers to nontraumatic, spontaneous, intraparenchymal, intraventricular, or subarachnoid hemorrhage.

Epidemiology

  • Isolated intraventricular hemorrhage is rare beyond the newborn period.
  • Trauma: most common cause of ICH in children
  • Arteriovenous malformations (AVMs): most common cause of nontraumatic ICH in children

Incidence

Incidence of hemorrhagic (nontraumatic) stroke is 1.1 per 100,000 person years.

Risk Factors

  • Trauma is the number one cause of ICH in children.
  • Ruptured vascular malformations are the most common cause of nontraumatic ICH in children.
  • Additional risk factors include:
    • Hereditary disorders of coagulation
    • Congenital heart disease
    • Cancer
    • Hypertension

Genetics

  • Multiple cerebral cavernomas may be associated with autosomal dominant trait with CCM1, CCM2, and CCM3.
  • Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant condition associated with cerebral and visceral AVMs, frequent nosebleeds, and mucocutaneous telangiectasias.

General Prevention

  • Automobile seat belts
  • Bicycle, skating, and skateboarding helmets
  • Child abuse prevention
  • Diving safety practices
  • Preventing falls
  • Maintaining safe driving speeds
  • Keeping children away from firearms
  • Hematologic monitoring for those at risk for hemorrhage due to bleeding disorders
  • Drug abuse prevention

Pathophysiology

  • Epidural hematoma (blood between the skull and the dura mater) is typically the result of a middle meningeal artery tear following temporal bone fracture; may also arise from dural venous sinus laceration.
  • Subdural hematoma (blood between the dura mater and the arachnoid membrane) is frequently venous, from stretching and tearing of bridging cortical veins from trauma or coagulopathy.
  • Subarachnoid hemorrhage (blood between the arachnoid membrane and brain) can be caused by a ruptured intracranial aneurysm, AVM, or trauma.
  • Intraparenchymal hemorrhage can be a result of trauma, infections (herpes simplex encephalitis, bacterial endocarditis), coagulopathy, brain tumors, Moyamoya arteriopathy, venous sinus thrombosis, or hemorrhagic conversion of ischemic stroke.
  • Intraventricular hemorrhage (IVH): may occur in isolation (more frequent in preterm infants <36 weeks’ gestation) or in a mixed pattern with intraparenchymal or subarachnoid hemorrhage. In term infants, rule out venous sinus thrombosis (especially in patients with accompanying thalamic hemorrhage).
  • Four grades of neonatal IVH:
    • Grade I: IVH isolated to 1 or both germinal matrices
    • Grade II: IVH without ventricular dilatation
    • Grade III: IVH with ventricular dilatation (hydrocephalus)
    • Grade IV: IVH with ventricular dilatation and extension into the periventricular white matter

Etiology

  • Vascular
    • Congenital vascular anomalies: AVM, aneurysm, cavernous hemangioma, arteriovenous fistula, vein of Galen malformation
    • Developmental vasculopathy: Ehlers-Danlos syndrome type IV, Moyamoya arteriopathy, sickle cell disease
    • Acquired vasculopathy: hypertension, posterior reversible encephalopathy syndrome, reversible vasoconstricition syndrome, mycotic aneurysm, vasculitis (cocaine, inflammatory diseases), cerebral venous sinus thrombosis, hemorrhagic conversion of ischemic stroke, brain tumor
  • Hematologic abnormalities: thrombocytopenia, hemophilia, sickle cell disease, liver failure, disseminated intravascular coagulation, iatrogenic (ECMO or anticoagulation therapy), hypercoagulability of malignancy
  • Traumatic
    • Accidental injury
    • Nonaccidental injury
ALERT
ICH, especially in young infants and children without an obvious etiology, should raise the suspicion of nonaccidental trauma.

Commonly Associated Conditions

  • Prematurity
  • Hemophilia (prevalence of ICH 3–12%)
  • Sickle cell disease (250-fold increased risk of ICH)
  • Bacterial endocarditis
  • Venous infarction
  • Arterial infarction
  • Alcohol, cocaine, and other sympathomimetics

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