FIG 2. Carotid and vertebral angiograms.

A, Left common carotid artery angiogram demonstrates a DAVF in the torcular region. It is supplied by both the occipital and middle meningeal arteries and drains in a retrograde fashion in the superior sagittal and straight sinuses. Note the presence of a falcine sinus.

B, Venous phase of a left vertebral angiogram shows substantial venous stagnation in the posterior fossa. Note the dilated premedullary and retromedullary veins.