The Anatomy Of A Stroke

November 22, 1985|By G. Timothy Johnson, M.D.

Dear Dr. Johnson: What exactly is a stroke, and what can cause it?

A stroke means that blood supply to the brain has been interrupted, resulting in diminished and inadequate blood supply to brain tissue. Depending upon the part of the brain affected, various symptoms result that are described clinically as a ``stroke``--or in the East as a ``shock.``

(Technically, a shock refers to bodywide diminished blood flow rather than the localized diminished blood flow to the brain signified by the word


Therefore, anything that interferes with blood flow to the brain can result in a stroke. The most common causes of diminished blood flow are problems in the blood vessels of the neck and brain itself. The two most common problems are clot formation--resulting in blocked blood flow--and leakage or breakage of blood vessels, resulting in actual bleeding at the site of breakage--and interrupted blood flow beyond that point.

However, there are many other possible causes of diminished blood flow to the brain, ranging from side effects of drugs that cause poor blood flow to the brain to a heart attack that causes inadequate heart pumping and, therefore, diminished blood flow to the brain. Indeed, sometimes a patient comes in with symptoms of a stroke and a routing check on heart function via an electrocardiogram demonstrates that the actual underlying problem is a heart attack.

In short, when an individual demonstrates symptoms of interrupted or diminished blood flow to the brain, a search must be conducted for many possible underlying causes.

Dear Dr. Johnson: Isn`t cheese worse for you than milk when it comes to heart disease?

Cheese certainly is a concentrated source of saturated fat and cholesterol and indeed might be described essentially as a concentrated form of milk. Therefore, it has the potential for increasing blood levels of cholesterol, which in turn is a known risk factor for heart disease. Whether or not it is ``worse`` than milk in any given individual depends on many other factors, including that individual`s ability to handle extra loads of fat and cholesterol in his or her diet.

On the positive side, cheese also is an excellent source of quality protein--as is milk--and likewise, a good source of calcium.

On balance, however, cheese cannot be regarded as a health food for those who are trying to reduce their risk for heart disease.

Do you suffer from sinus, tension or migraine headache? Find out what you should do to avoid or minimize headaches in Dr. Johnson`s booklet. For a copy, send $2.25 to ``Headache,`` P.O. Box 4406, Orlando, Fla. 32802-4406. Make checks payable to Newspaperbooks.