Cerebral aneurysms, also called brain aneurysms, are a cerebrovascular issue in which weakness in the walls of a cerebral artery causes localized dilation or ballooning in the blood vessel. Small, unchanging aneurysms may produce very few symptoms. However, before a larger aneurysm ruptures, individuals may experience sudden or severe headaches, nausea, vomiting and vision problems. The rupture may also directly cause serious damage directly to the brain, usually from the bleeding itself-this is a hemorrhagic stroke that can lead to and may cause arm or leg weakness or paralysis and speech troubles. Cerebral aneurysms may result due to congenital defect, high blood pressure or head trauma. Onsets are sometimes sudden and without warning, and such ruptures are extremely dangerous and usually result in bleeding into the brain itself, leading to a subarachnoid hemorrhage, which then constitutes a stroke. This condition may lead to death or permanent disability for some individuals.