An aneurysm is the widening of an arterial wall, and sometimes this weak bulging spot can bleed. Some aneurysms rupture or hemorrhage which may cause a severe, blinding headache often described as the worst headache of my life which becomes more unbearable every minute. Other symptoms may include loss of consciousness, vomiting, nausea, stiff neck, blurred vision, sensitivity to light, sensitivity to sound, inability to speak or understand words, weak or paralyzed limbs, seizures, high blood pressure, or a low pulse. Pain may also be felt in the entire head, forehead, neck, and shoulders. Many people live their entire lives with an undiagnosed, unruptured aneurysm which is small and causes no problems or bleeding.
Some unruptured aneurysms do cause symptoms depending on their size and location in the brain.
No study has been undertaken to determine the incidence of brain aneurysms in the general population. Lastly, one study estimates that as many as 400,000 people in the U.S. may have a brain aneurysm of significant size. The highest incidence of brain aneurysms is in people in their 50's and 60's. It is rare for an aneurysm to occur in the very young or very old. With an SAH, the blood from the hemorrhage goes between the brain and the brain s covering.