Cerebral edema early stroke or hypoxia, cardiac arrest, and pseudotumor cerebri. During an ischemic stroke, a lack of oxygen and glucose leads to a breakdown of the sodium-calcium pumps on brain cell membranes, which in turn results in a massive buildup of sodium and calcium intracellularly. This causes a rapid uptake of water and subsequent swelling of the cells. It is this swelling of the individual cells of the brain that is seen as the main distinguishing characteristic of cytotoxic edema, as opposed to vasogenic edema, wherein the influx of fluid is typically seen in the interstitial space rather than within the
Cerebral edema cells themselves. While not all patients who have experienced a stroke will develop a severe edema, those who do have a very poor prognosis. In most instances, cytotoxic and vasogenic edema occur together. It is generally accepted that cytotoxic edema is dominant immediately following an injury or infarct, but gives way to a vasogenic edema that can persist for several days or longer. The use of specific MRI techniques has allowed for some differentiation between the two mechanisms and suggests that in the case of trauma, the cytotoxic response dominates Normally, the osmolality of cerebral-spinal fluid (CSF) and extracellular fluid