Persistent Primitive Trigeminal Artery Associated With Anterior Communicating Artery Aneurysm and Hypoplastic Vertebral Artery.

The persistent trigeminal artery is one of the presegmental arteries in the embryonic period; in some rare cases, it is associated with cerebral aneurysm but as a cause of subarachnoid hemorrhage (SAH) has not been described in the literature. We report a patient who presented a Fisher IV SAH associated with a ruptured intracranial aneurysm. The performed cerebral angiography demonstrated the presence of aneurysm in the anterior communicating artery associated to hypoplastic vertebral artery on the same side. We considered those finding coincidental. The coexistence of saccular aneurysm with anatomical variations in the intracranial vasculature is briefly discussed. It was managed by endovascular embolization. The patient returned to normal activities.