- Aneurysmal dilatation of median prosencephalic vein of Markowski due to arteriovenous fistula that occurs in 6-11 weeks of gestation
- 30% of all pediatric vascular malformations
- M:F = 2:1
- Most common extra cardiac cause of high output cardiac failure
- Presents with heart failure or hydrocephalus
- Two types: choroidal and mural. Choroidal has feeders from pericallosal, choroidal or thalamoperforating arteries. Mural has few feeders from uni or bilateral collicular or posterior choroidal arteries
Imaging
Chest radiograph
- Cardiomegaly
- Wide mediastinum
CT
- Plain study: venous pouch slightly hype dense. Wall calcification seen when there is thrombus in the aneurysm. Hydrocephalus, ischemia, parenchymal atrophy
- CECT: enhancing feeding arteries and veins
- CTA: excellent
MRI
- T1: arterial flow voids. MPV shows flow void or mixed signal. Intraluminal thrombus appears bright.
- T2:same as T1
- MRA: excellent