By John C. Wolf, D.O.
Associate Professor of Family Medicine
Ohio University College of Osteopathic Medicine

WIFE'S SYMPTOMS MAY REQUIRE TESTS TO RULE OUT CEREBRAL ANEURYSM

Question: My wife has had severe headaches, cold sweats and blackout spells. From my readings I think these could be symptoms of an aneurysm. If so, what can cause it to progress to the serious condition of rupture?

Answer: The symptoms your wife has been experiencing can be due to a number of conditions. When faced with a diagnostic puzzle, we doctors consider the most common conditions first. Migraine headaches, diabetes or even anxiety are dramatically more likely to be the cause of her symptoms than is a cerebral aneurysm. Despite the statistics involved, it is also part of a good diagnostic workup to consider the less likely -- but very serious -- conditions that can cause a given set of symptoms.
Before I go any further, let me explain a few terms. An aneurysm is a dilation or swelling of a blood vessel. These are most common in arteries because they operate under higher pressure than do veins. The aneurysm comes about because of weakening in the artery wall. The term "cerebral" pertains to the brain. Therefore, a cerebral aneurysm is an aneurysm of one of the many arteries that supply blood to the brain.
Cerebral aneurysms are relatively common. Fifteen to 20 percent of the population have very small ones (2mm or smaller) and 5 percent have more significant ones measuring 5mm or greater. Despite the high prevalence of this disorder and the tendency for any aneurysm to enlarge with time, the frequency of bleeding from them is actually rather low -- about ten per 100,000 population.
When an aneurysm ruptures it causes problems by three different mechanisms:
*First, the rupture reduces or eliminates blood supply to some part of the brain. A vigorous supply of oxygen and blood sugar (glucose) is necessary for the brain cells to function. Without these vital nutrients being supplied by the blood, the brain cells can't function properly and in severe cases will die. This is what we call a stroke!
*Second, the physical swelling of an aneurysm or the displacement of brain cells caused by blood outside the artery increases the pressure inside the skull. As a result not only the brain cells in the area of the aneurysm are "squeezed" but also the whole brain is affected by the increased pressure. This prevents the sufferer from performing his or her usual thinking and life-sustaining tasks.
*Third, despite the fact that the brain itself cannot feel pain, a ruptured aneurysm can actually be quite painful. This is because the pressure inside the skull impinges on other structures that do have pain nerve endings.
Cerebral aneurysms pose very little risk when they are small. Larger ones, those over 5mm, have some risk of rupturing with the passage of time. Consequently, they should be evaluated by a neurosurgeon. The greatest benefit for most people with an asymptomatic and small aneurysm, however, comes from periodic evaluation and control, when necessary, of blood pressure. High blood pressure is probably the greatest contributing factor to aneurysm rupture. Heredity, high cholesterol and other factors play a role as well.
From simple statistics alone, it is unlikely that your wife's symptoms are due to a cerebral aneurysm. This is particularly true if she is under 50 and has no family history of cerebral hemorrhage. Despite this, you should mention your concerns to her doctor the next time she is there. This will allow all three of you to discuss your worries. Perhaps an MRA (Magnetic Resonance Angiogram -- a special form of MRI) or an angiogram where dye is injected into the arteries will be necessary to evaluate her cerebral arteries.

"Family Medicine" is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, P.O. Box 110, Athens, Ohio 45701. Past columns are available online at http://www.FamilyMedicineNews.org.