Persistent trigeminal artery associated with intracranial arterial aneurysm

Area of Science:

• Neurology
• Vascular Neurology
• Neuroimaging

Background:

• The persistent trigeminal artery is a rare congenital vascular anomaly representing a persistent fetal connection between the internal carotid artery and the vertebrobasilar system.
• Intracranial aneurysms, particularly those associated with the posterior communicating artery, pose significant risks of rupture and subarachnoid hemorrhage.

Observation:

• This report details two cases of patients presenting with ruptured intracranial aneurysms originating from the internal carotid artery at the posterior communicating artery junction.
• In both patients, a persistent trigeminal artery was incidentally identified on diagnostic imaging.
• One patient had an aneurysm successfully clipped, while the other experienced a fatal outcome during emergency angiography.

Findings:

• The persistent trigeminal artery was considered an incidental finding in both cases and not the source of the aneurysm.
• The ruptured aneurysms arose from the ipsilateral internal carotid artery, adjacent to the origin of the anomalous vessel.
• Outcomes varied significantly, with one patient surviving and the other succumbing to complications.

Implications:

• This case series highlights the importance of recognizing the persistent trigeminal artery as an incidental finding during the evaluation of intracranial aneurysms.
• It underscores the critical need for prompt diagnosis and management of ruptured intracranial aneurysms, regardless of associated vascular anomalies.
• Further research may elucidate any potential, albeit indirect, associations between persistent trigeminal artery and aneurysm formation or rupture risk.