FIG 1. Schematic representation of an AVM model in sheep. Circulatory flow is diverted from the contralateral side (left) of the carotid artery through both carotid retia (RM) to the right carotid artery and jugular vein with retrograde flow following surgical creation of an anastomosis. Note the blood flow direction (arrows) after creation of a carotid-jugular anastomosis