From: deputydog23x@gmail.com   
      
   The New Jersey Comprehensive Stroke Center at University Hospital   
      
   Types of Stroke   
       
      
   There are two main types of stroke -- ischemic and hemorrhagic. Ischemic   
   stroke is more common and occurs when blood flow to a part or parts of the   
   brain is stopped by a blockage in a vessel. Hemorrhagic stroke is more deadly   
   and occurs when a weakened    
   vessel tears or ruptures, diverting blood flow from its normal course and   
   instead leaking or spilling it into or around the brain itself.   
      
   	   
   (left) Illustration of Ischemic Stroke showing blockage of one of the brain's   
   arteries.(right) CT scan of Hemorrhagic Stroke. Arrow points to the area of   
   blood in the brain.   
   Treatment for each type is significantly different. In fact, treating an   
   ischemic stroke as though it were hemorrhagic or vice versa could have   
   life-threatening consequences. Therefore, a reliable determination (diagnosis)   
   of which type has occurred is    
   critical before treatment can begin.   
      
   There is a third type referred to as transient ischemic attack (TIA) or   
   "mini-stroke." While they are not true strokes because the symptoms are   
   temporary, TIAs are usually a warning sign of a stroke to come. Heeding the   
   warning signs of TIAs and treating    
   the underlying risk factors that trigger them can prevent many strokes.   
      
   Transient Ischemic Attack (TIA)   
   A TIA is caused by a brief pause in blood flow to part of the brain -- the   
   result of a temporary or partial blockage. The symptoms of a TIA resemble   
   those of a stroke but they do not last as long. Most symptoms disappear within   
   an hour, although some may    
   persist for up to 24 hours. Usually, no permanent brain damage occurs as a   
   result of a TIA. According to the National Stroke Association, approximately 5   
   million Americans have experienced at least one TIA.   
      
   TIA Symptoms   
      
   Patients suffering a TIA may describe a "veil" or "window shade" partly   
   covering the vision of one eye that clears up spontaneously after several   
   minutes. This represents the temporary blockage (occlusion) of the retinal   
   artery to the eye. There may also    
   be dizziness, imbalance, loss of coordination, confusion, difficulty speaking   
   or understanding, and generalized weakness.   
      
   There is no way to differentiate the temporary symptoms of a TIA from those of   
   an acute stroke. All patients need medical evaluation urgently. About   
   one-third of those who have a TIA eventually will have an acute stroke. Many   
   strokes can be prevented by    
   heeding TIA warning signs and treating underlying risk factors.   
      
   Ischemic Stroke   
   The vast majority of strokes - approximately 83 percent -- are ischemic. They   
   are caused by an obstruction of an artery leading to or in the brain,   
   preventing oxygenated blood from reaching parts of the brain that the artery   
   feeds. Ischemic strokes are    
   either thrombotic or embolic, depending on where the obstruction or clot   
   (thrombus or embolism), causing the blockage originated:   
      
   Thrombotic Ischemic Stroke   
      
   Thrombotic stroke is caused by a thrombus (blood clot) that develops in an   
   artery supplying blood to the brain -- usually because of a repeated buildup   
   of fatty deposits, calcium and clotting factors, such as fibrinogen and   
   cholesterol, carried in the    
   blood. The body perceives the buildup as an injury to the vessel wall and   
   responds the way it would to a small wound -- it forms blood clots. The blood   
   clots get caught on the plaque on the vessel walls, eventually stopping blood   
   flow.   
      
   There are two types of thrombotic stroke:   
      
   Large vessel thrombosis, the most common form of thrombotic stroke, occurs in   
   the brain's larger arteries. The impact and damage tends to be magnified   
   because all the smaller vessels that the artery feeds are deprived of blood.   
   In most cases, large    
   vessel thrombosis is caused by a combination of long-term plaque buildup   
   (atherosclerosis) followed by rapid blood clot formation. High cholesterol is   
   a common risk factor for this type of stroke.   
   Small vessel disease (lacunar infarction) occurs when blood flow is blocked to   
   a very small arterial vessel. It has been linked to high blood pressure   
   (hypertension) and is an indicator of atherosclerotic disease.   
   Thrombotic disease accounts for about 60 percent of acute ischemic strokes. Of   
   those, approximately 70 percent are large vessel thrombosis.   
      
   Embolic Ischemic Stroke   
      
   A blood clot that forms in one area of the body and travels through the   
   bloodstream to another where it may lodge is called an embolus. In the case of   
   embolic stroke, the clot forms outside of the brain - usually in the heart or   
   large arteries of the    
   upper chest and neck - and is transported through the bloodstream to the   
   brain. There it eventually reaches a blood vessel small enough to block its   
   passage.   
      
   Emboli can be fat globules, air bubbles or, most commonly, bits and pieces of   
   atherosclerotic plaque, such as lipid debris, that have detached from an   
   artery wall. Many emboli are caused by a cardiac condition called atrial   
   fibrillation--an abnormal,    
   rapid heartbeat in which the two small upper chambers of the heart (called the   
   atria) quiver instead of beating. Quivers cause the blood to pool, forming   
   clots that can travel to the brain and cause a stroke. Cardiac sources of   
   embolism account for 80    
   percent of embolic ischemic strokes.   
      
   Ischemic Stroke Symptoms   
      
   The signs of ischemic stroke are similar to those of a TIA, except the damage   
   can be permanent. The most common indicator is sudden weakness of the face,   
   arm or leg, most often on one side of the body. Other warning signs may   
   include:   
      
   sudden numbness of the face, arm, or leg, especially on one side of the body;   
   sudden confusion, trouble speaking or understanding speech;   
   sudden trouble seeing in one or both eyes;   
   sudden trouble walking, dizziness, loss of balance or coordination; and/or   
   sudden severe headache with no known cause (most common with hemorrhagic   
   stroke).   
   The symptoms depend on the side of the brain that's affected, the part of the   
   brain, and how severely the brain is injured. Stroke may be associated with a   
   headache, or may be completely painless. Therefore, each person may have   
   different warning signs.   
      
   Hemorrhagic Stroke   
      
   [continued in next message]   
      
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