Introduction: The Medial Tentorial Artery (MTA) also known as the Bernasconi - Cassinari Artery, is a branch of the meningohypophyseal trunk of the cavernous segment of the internal carotid artery, is not easily identified in angiograms, it is known mainly as the main vascular aference of the tentorial tumors, and also seen in dural arteriovenous fistulas. We present a case of pontomesencephalic bleeding in a 26-year-old patient with angiographic evidence of an arteriovenous fistula from the MTA to the vein of Galen, endovascular management was performed with difficulties for coiling the MTA, therefore microsurgical management with intraoperative angiography was decided with adequate occlusion of the arteriovenous fistula.

Methods: we report a case with a arterovenous malformation of the Bernasconi Cassinari Artery, a rare case of dural arterovenous malformation

Results: the endovascular treatment was difficult because the access to the artery could not be obtained, therefore it required microvascular occlusion with an intraoperative angiographic control with adequate occlusion of the malformation, the patient evolved adequately

Conclusions: The gold standard of the management of the fistula of the bernasconi cassinari artery are endovascular, is described in the literature as single cases which were not performed in a micro-surgical way, since we do not have endovascular control we perform microvascular occlusion with angiographic intraoperative control with succesful occlusion with the complet treatment for the patient.

Patient Care: the microsurgical treatment of this uncommon malformation should be taken into account with intraoperative angiographic control in cases of difficulties for endovascular management

Learning Objectives: microsulgical treatment of a fistula arterovenous malformation of the Bernasconi Cassinari Artery

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