About Acute Ischemic Stroke (AIS)
Acute ischemic stroke (AIS) is characterized by the rapidly developing loss of brain function due to a blockage of blood flow to the brain. According to the U.S. Center for Disease Control, stroke causes approximately one out of every 20 deaths in the U.S. each year. Nearly nine out of 10 strokes are AIS.
When a blood vessel in the brain becomes blocked during a stroke, a core area of the affected brain tissue will typically suffer a nearly complete loss of blood flow, with a surrounding area (the “penumbra”) experiencing a partial loss of blood flow. Cells in the core area rapidly depleted of their oxygen and glucose stores, leading, often within minutes, to cell death. The cells in the penumbral area may remain viable for several hours but are eventually at risk of tissue damage from reduced oxygen and glucose availability and compression resulting from fluid buildup in the brain.
A stroke can lead to permanent brain damage, including memory loss, speech problems, reading and comprehension difficulties, physical disabilities, and emotional/behavioral problems. Many patients require extended hospitalization, physical therapy or rehabilitation, or long-term institutional or family care.