Ruptured aneurysm originating from an infundibular dilatation of the posterior communicating artery associated with a hyperplastic anterior choroidal artery: A case report

Background: A hyperplastic anterior choroidal artery (AChA) resulting from incomplete distal annexation between the primitive AChoA and the posterior cerebral artery, increases the risk of cerebral aneurysms at the branching site of the AChA and other distant locations. It has also been reported that infundibular dilatation (IFD) rarely progresses into a saccular aneurysm with a risk of rupture.Case report: A 59-year-old man presented with sudden onset of headache and vomiting due to the rupture of an aneurysm originating from an IFD of the posterior communicating artery (PcomA) associated with a hyperplastic AChA. The aneurysm was successfully treated using coil embolization.Conclusion: To the best of our knowledge, this is the first reported case of a ruptured aneurysm originating from an IFD of the PcomA associated with a hyperplastic AChA, accompanied by a review of previous case reports. Neurosurgeons should be aware of this anomaly to prevent critical events.