My sister has cerebral aneurysm. what does this mean?

Cerebral aneurysms: An cerebral aneurysm is a focal outpouching or dilation of a portion of an artery providing blood to the brain. Aneurysms may rupture causing death or stroke or they may remain stable for many decades.

Cerebral aneurysm: It is a dilitation of a small artery in the brain. It is at a risk of rupturing if is large. You should be evaluated by a neurosurgeon. Very small aneurysms are left alone and larger ones need treatment.