Persistence of a trigeminal artery associated with a posterior meningeal artery aneurysm: case report and literature review.

A 59-year-old female presented with severe headache and trouble of consciousness. The CT showed a subarachnoid hemorrhage FISHER IV with a hematoma of the right cerebellum. The angiography discovered a persistent left trigeminal artery associated with an aneurysm of the right posterior meningeal artery. The attempt of embolization failed and the patient suffered cerebral vasospasm and died. The persistence of a trigeminal artery is found in 0.1-0.6% of the population. It is the most frequent embryological carotid-vertebral anastomosis. It appears at the fifth week of development and disappears when the embryo reaches 5-7 mm. This embryological persistence is associated with numerous vascular abnormalities. The literature review showed the presence of those aneurysms in the trigeminal artery itself or the communicating artery. The association that we described is the first to our knowledge. Therefore, this association is particular and interesting to expose.