REFERAT ENGLEZA: STROKE

label Referate autorenew 2025-09-29, 16:56 history_edu Anonim
Stroke DefinitionFactsTypes of strokes Exploration What is a stroke?A stroke is damage to part of the brain tissue as a result of a loss of blood and oxygen. A stroke can also be called a "brain attack." Why does a stroke affect different parts of the body? Nerve cells in the brain tissue communicate with other cells to control such functions as memory, speech, and movement. When a stroke happens, nerve cells in the brain tissue become injured. As a result, they cannot communicate with other cells, and functions are impaired. If a stroke occurs on the right side of the brain, the left side of the body is affected, and vice versa.What happens during a stroke?Brain tissue needs a constant supply of oxygen and nutrients to keep nerve cells and other parts of the tissue alive and functioning. The brain cannot store oxygen, so it relies on a network of blood vessels to provide it with blood that is rich in oxygen.A stroke occurs when one of these blood vessels becomes damaged or blocked, preventing blood from reaching a part of the brain tissue. When the tissue is cut off from its supply of oxygen for more than three to four minutes, it begins to die. Transient ischemic attack "mini stroke" - This occurs when blood flow to a certain part of the brain is cut off for a short period of time, usually 15 minutes or less. A TIA is a painless episode but is a warning sign that something is wrong, and it should be treated as seriously as a stroke. Ischemic stroke - This occurs when a blood vessel in the brain develops a clot and cuts off the blood supply to the brain. A blood clot that forms in a blood vessel in the brain is called a "thrombus." A blood clot that forms in another part of the body, such as the neck or lining of the heart, and travels to the brain is called an "embolus." Blood clots often result from a condition called "atherosclerosis," the build-up of fatty deposits within the blood vessel walls.Hemorrhagic stroke - This occurs when a weakened blood vessel in the brain ruptures. This type of stroke is the most serious. A hemorrhage, or bleeding from the blood vessel, happens suddenly. The force of blood that escapes from the blood vessel can also damage surrounding brain tissue. ANGIOLOGYThe exploration of the main vessels to the brain, using contrast substance. This procedure is used to discover anormal vessels branchs, or a possible anevrysmeTomographyThis cat scan showes a recent stoke and the area in white wich is affected, in contrast with the rest of the brain wich function normaly.