| Definition : a non-traumatic interruption in the blood supply to an organ. It usually refers to such interruptions in the blood supply to the brain. There are two varieties, the bleeding sort in which a blood vessel leaks blood into tissues. In the brain, these produce hematomas (ie, pools of blood within the skull). The other kind is an ischemic stroke in which the flow of blood is interrupted, often because of vessel blockage by a clot or plaque. Both kill tissue and can cause considerable damage, including death. |