Vascular Malformations

  • Malformations with arterio-venous shunting

    • AVMs

    • Dural AV fistula

    • Vein of Galen malformations

  • Malformations without arterio-venous shunting

    • Developmental venous anomalies

    • Sinus pericranii

    • Cavernous malforation

    • Capillary telangiectasia

Arteriovenous Malformation

  • Arterial to venous connection without capillary bed in between with clear nidus

  • Age 20-40 yo

  • >80% are supratentorial (note that these are intraparenchymal)

  • Typically one main feeding artery and draining vein

  • Uncommon in posterior fossa

  • Spetzler-Martin classification

    • Higher # = more likely to bleed during treatment

      • Therefore high # = worse case = not treated basically

    • Components

      • Size

      • Superficial vs Deep drainage

      • Eloquence

        • Basically everything is eloquent except non-dominant temporal lobe

  • Multiple —> syndromic —> HHT

Carotid-Cavernous Fistula

  • Type of dural AV fistula

  • Direct CCF

    • Cavernous ICA ruptures within cavernous sinus

    • High flow lesion

    • 2/2 Trauma - skull base fractures

  • Indirect CCF

    • Slow flow, low pressure

    • Fistula between dural branches of cavernous portion of the ICA cavernous sinus

    • 2/2 degenerative changes

  • Prominent superior ophthalmic vein and cavernous sinus

Developmental Venous Anomaly

  • >70 at white matter adjacent to frontal horn of lateral ventricle

  • Upside down jellyfish/umbrella looking/medusa head

  • Multiple small veins that all drain into a single larger vein

  • Commonly co-occur with cavernous malformations

Cerebral Proliferative Angiopathy

  • Basically AVM but with interspersed areas of normal brain parenchyma throughout the vascular malformation

  • Multiple smaller arterial feeders

  • No definitive identifiable nidus

Vein of Galen Malformation

  • Direct connection between deep choroidal arteries and medial prosencephalic vein of Markowski (vein of galen precursor)

  • Mutation in Ephrin gene

  • Straight sinus is hypoplastic/absent with venous drainage into persistent fetal falcine sinus

Sinus Pericranii

  • >70 at white matter adjacent to frontal horn of lateral ventricle

  • Upside down jellyfish/umbrella looking/medusa head

  • Multiple small veins that all drain into a single larger vein

Dural AV fistula

  • Connection between meningeal arteries and venules in the wall of a dural venous sinus

  • Age 40-60

  • Majority in posterior fossa, most commonly at junction of sigmoid and transverse sinuses

Cavernous Malformation (Cavernoma)

  • Masses of immature blood vessels

  • Popcorn appearance with hypointense hemosiderin ring

  • No enhancement

  • Fluid-fluid levels can be seen

  • Zabramski classification

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