The progression of an infundibulum to aneurysm formation and rupture: case report and literature review.
OBJECTIVE
Infundibula (IFs) are funnel-shaped symmetrical enlargements that occur at the origins of cerebral arteries and are apparent on 7 to 25% of otherwise normal angiograms. They are frequently considered as normal anatomic variants of no pathogenic significance.


METHODS
We report the case of a ruptured posterior communicating artery aneurysm that had developed at the site of a previously known IF in a 49-year-old hypertensive woman. She had a poor conscious level at admission, with widespread subarachnoid hemorrhage and obstructive hydrocephalus.


METHODS
The patient was immediately ventilated, and an external ventricular drain was inserted. The aneurysm was successfully clipped; however, secondary hemorrhage occurred both before and during craniotomy. She developed marked hypernatremia and subsequently died.


CONCLUSIONS
This is the 11th case of IF-to-aneurysm progression reported. It suggests that in certain cases, serial investigations may be indicated with IFs to detect aneurysm formation and preempt rupture.
Marshman
L A
LA
Department of Neurosurgery, Hurstwood Park Neurological Centre, Princess Royal Hospital, West Sussex, England.
Ward
P J
PJ
Walter
P H
PH
Dossetor
R S
RS
D017542:Aneurysm, Ruptured / Q000473:pathology*; D002339:Carotid Arteries / Q000473:pathology; D002536:Cerebral Arteries / Q000033:anatomy & histology / Q000473:pathology*; D003399:Craniotomy; D018450:Disease Progression; D004322:Drainage; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000209:etiology / Q000601:surgery; D006955:Hypernatremia / Q000209:etiology; D006973:Hypertension / Q000150:complications; D002532:Intracranial Aneurysm / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D012008:Recurrence; D012422:Rupture, Spontaneous; D013345:Subarachnoid Hemorrhage / Q000209:etiology