Dural Arteriovenous Fistula with Unusual Drainage Route Beneath Vein of Foramen Caecum

The existence of the vein of the foramen caecum (VFC) in humans is still controversial and its existence in humans is questioned by various authors. Vein of foramen caecum can be clinically important, since it is a potential pathway for intracranial spread of nasal infectious and tumoral processes. Due to small size, VFC may not be visible on normal angiograms. Arterio-venous shunts frequently lead to vein enlargement and finally better visibility. We report two cases of cranial Dural Arterio-Venous Fistula (DAVF) of the anterior cranial fossa, draining through an enlarged VFC. This demonstrates the role of VFC as a connection between vascular territories of ophthalmic and Sphenopalatine arteries; to our knowledge, a DAVF in this location has never been described: since occlusion of the primary draining vein is the target of the treatment, a correct identification is mandatory.