Congenital cerebral vascular malformation with mature venous elements
Umbrella-like collection of enlarged medullary (white matter) veins ("Medusa head")
At angle of ventricle
Converge on single enlarged collector vein
Imaging
CT often normal but may see hyperdense collector vein
MR
Hypointense on SWI
Strong enhancement
T1 can be normal if small and signal is variable depending on size and flow (eg. flow void may or may not be present)
T2 tubular flow void present
FLAIR usually normal but occasionally will see hyperintensity adject which reflects venous congestion/ischemia
Best imaging is T1 w/ contrast which shows strong enhancement
Can be mixed with cavernous malformations (mixed vascular malformation) with coexisting cavernous and or capillary malformations occurring 15-20% of the time
More common asymptomatic
0.15% risk of hemorrhage per lesion per year
Solitary DVAs usually not treated as attempts can lead to venous infarction
If mixed then treatment depends on the mixed component
Per CTC it is a "do not touch" lesion. If resected can lead to debilitating venous infarct similar to acute thrombosis of DVA. DVA must be preserved if an adjacent cavernous malformation is resected