• Incidence: 0.14%
• Pial/Parenchmal 70-93% supratentorial
• Symptomatic at 20-40yrs (80% Dx by age 40)
• Presentation:
- 50% w/intracerebral hemorrhage
- 33% w/SAH
- 25% w/Sz (more common w/superficial lesions)
• Bleeding and re-bleeding:
- Incidence of 1st bleed is 3%/yr
- Rebleed rate of 6% in 12 months
- Rebleed 3%/yr after first year
• Mortality: 10-17%
• Morbidity: 10%
• Nidus - dilated vascular loops with abnormal arterial to venous connection
Dilated Arterial feeders, abnormal arterial collaterals and aneurysms on feeding vessels
Dilated Venous drainage and varices (may act as a mass)

Intervening neural tissue (gliotic/ischemic)between vessels

Angiography: 85% Pial (pial feeders)

15% Dural (dural feeders, usually acquired)
Intra-nidus aneurysms - a source of bleeding

• Ischemic Sx when CBF drops below 15-18 ml/100gm/min

• MetHgb (T1 bright): lasts for mo-yrs.
• Hemosiderin (T2 dark): lasts for years, preferential T2 shortening, present in 63% (SE) and 95% (GRE) of AVM's
• Hemosiderosis: meningeal staining from recurrent SAH - subfrontal, temporal, pofo (near petrous apex) -

• INCREASED RISK OF BLEED:
central/deep venous drainage
intranidal aneurysm
periventricular location
• LOWER RISK OF BLEED:
angiomatous change (mult dilated cortical aa. feeders)

• TREATMENT: Embolization, excision, radiation
isobutyl-2-cyanoacrylate/iophendylate (Pantopaque) is bright on T1W
Radiation - proton-beam and stereotaxic

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