Medicine: Accidents in the Brain

Each year, by conservative estimate, at least 175,000 people in the U.S. die of strokes—accidents to the arteries in the brain. Among 1,800,000 survivors of strokes, a large number are severely para lyzed, and many drag out a hopeless existence, often requiring the care of three or four persons. Yet until recently, despite their frequency and severity, strokes have been neglected by medical researchers because it seemed that so little could be done for their victims. Last week Cornell University's Dr. Irving S. Wright reported the hopeful findings of a just-concluded conference at Princeton (paid for by the National Heart Institute, sponsored by the American Heart Association) of 50 assorted specialists—neurologists, neuro surgeons, physiologists, pathologists, hematologists, internists. Gist of their conclusions: much more can be done to determine the exact nature of a stroke, and anticoagulant drugs show promise as a means of warding off recurrences.

All strokes damage the brain by shutting off the blood supply to cells. According to how this damage happens, strokes are divided into three major types:

1) shutdown in a brain artery by a clot,, called a thrombosis if the clot forms at the site, or an embolism if the clot is formed elsewhere—usually the heart—and travels through the arteries to the brain;

2) hemorrhage, or a blowout in a weakened artery wall; 3) aneurysm, a ballooning of weakened artery wall, which causes pressure on surrounding brain tissues. For all three categories, the experts reported advances in research and diagnosis as well as treatment.

Research Leads. Traditionally, the brain has been supposed to require a superabundant blood supply, but the difficulty has been to determine how much. Stockholm's Dr. Gustav Nylin reported that he had injected red blood cells labeled with radioactive thorium into healthy test subjects, discovered that the major blood flow through the brain is normally much less than previously believed—and notably less than in other body tissues. A series of blood-flow readings may help in the evaluation of treatment.

Cleveland's Dr. Arthur C. Corcoran checked stroke victims' blood pressure, found that abnormally high pressure predisposes a person to strokes, especially of the hemorrhagic type. In such cases it would be dangerous to use anticoagulant drugs (because of the risk of further hemorrhage); the Cleveland Clinic researchers have found that they could lower the blood pressure with hypotensive drugs, arid later use anticoagulants safely to minimize the risk of subsequent strokes.

Arteriosclerosis and specifically atherosclerosis (the form of the disease in which arteries are plugged by mushy, fatty deposits) is "as great a problem" in stroke victims as in coronary artery disease, said Dr. Wright. A stroke may either precede or follow a heart attack: the two are often associated, and the same patient is likely to have atherosclerosis in both cerebral and coronary arteries. As in heart disease, female sex hormones seem to exert a protective effect (reflected in the relative immunity of premenopausal women), but they cannot be given to men without feminizing them. Needed: a synthetic hormone that affords protection without feminization. Several laboratories are trying to produce one.