DURAL ARTERIOVENOUS-MALFORMATIONS OF THE ETHMOIDAL REGION - REPORT OF2 CASES

Dural arteriovenous malformations of the ethmoidal region are extremel y rare. They are usually supplied by the ipsilateral anterior ethmoida l artery with contralateral contribution in about half of the cases. T hey are characterized by a fistulous nidus within the dura, and their progression seems to involve a retrograde leptomeningeal vascular stas is with formation of varices and venous aneurysms. They have more prop ensity to rupture than dural malformations in other locations. Two pat ients who presented with an acute frontal hemorrhage are reported.