Ischemic Cerebral Edema

Abstract

Water content was measured in samples of brain obtained from cats four hours to 20 days after occlusion of one middle cerebral artery. Samples were categorized as nonischemic (from hemispheres opposite occluded arteries), ischemic, or infarcted, and as predominantly gray or white matter. When compared with samples from cats with sham operations, water content of each of the six types of tissue (including those from nonischemic hemispheres) was increased at four hours to three days after occlusion. The increase was maximal at two days. At all times, water content was greatest in infarcted tissue and least in nonischemic tissue, but from 4 to 20 days, differences were slight. Thus, unilateral experimental cerebral ischemia causes bilateral cerebral edema that is transient and more pronounced in infarcted and ischemic regions.