| Atherosclerosis is a systemic disease of the vessel wall that occurs in the aorta and in the carotid, coronary, and peripheral arteries, which represents as noninflammation, regression and hyperplasia , and results in vessel well thicking,stiffing,elasticity lowering and luminal diameter dimishing.The earlist atherosclerotic lesion was found in child and baby ,and was generally observed in adulthood ,which emerged as fatty streaking and progressed fibrous plaque with aging.Since atherosclerotic animal model was copied with high cholesterol feeding in 1908,it well be known that hyperlipemia was the cause of atherolerosis.According to purposes ,different investigator established animal model based on high lipid and cholesterol.Rabbit with high lipid diet for 8-12 weeks produced similarly to atherosclerotic lesion in human,and for 24-30 weeks formed typical atherosclerotic plaque.After ballon injury and high cholesterol diet of 10 weeks, New Zealand rabbits aorta developed severity atherosclerotic lesions .Plaque disruption animal model established after endothelial denudation and high cholesterol diet,plaque disruption triggered by using Russel's viper venpm ,then by histamine.Any model is based upon a limited set of assumptions and therefore by defaut has it's own limitations.A model often exaggerates only one feature of a complex process to make analysis more convenient and more accurate.lt stands true for traditional models of atherosclerosis,some of which are primarily driven by lipid accumulation and some of by cell proliferation.Nevertheless,these models facilitated accumulation of useful knowledge relevant to the mechanisms of plaque development.After therapies ,detecting and monitoring atherosclerotic lesions predominantly used imaging method including both noninvasive and invasive Angiography,however,has become the gold standard for diagnosis of coronary,carotid,and peripheral atery lesions, this imaging method does not image the vessel wall or provide information about the composition of the atherosclerotic plaque such as the vulnerable lipid-rich plaques or other histopathological features.Angiography may reveal advanced lesions, plaque disruption, luminal thrombosis, and calcification. One of the major limitations of angiography is that diffuse atherosclerotic disease may narrow the entire lumen of the artery, and as a result underestimate the degree of local stenosis. In addition, because some of the plaques may be displaced outward, the luminal diameter may appear normal despite significant disease. Noninvasive imaging method,such as ultrasound or MRI ,has being focused on evaluating atherosclerotic lesion.Pignoli firstly measured carotid intimal-medial thickess and suggested that early alteration of it's might result in atherosclerosis.The evidences shown that carotid and aorta atherosclerosis were approximately simultaneous,and earlier than coronary artery's.Carotid atherosclerosis was significantly associated with coronary heart disease and cerebrovascular event.The degree of carotid atherosclerosis has been predicted cardiovascular and cerebrovascular eventHigh-frequence ultrasound was mostly used to detect carotid and superficial artery atherosclerosis. When intimal-medial thickess was 1.0mm,1.5mm,there was plaque in approximately 30% ,90% of carotid, respectively .Currently,ultrasound has been screened early lesion of atherosclerosis.Studies has been proved that cardiovascular events resulted from plaque rupture but not from severity of stenosis.Diagnostic ultrasonography is increasingly used as a noninvasive method to study plaque morphology and composition.Carotid "soft plaque" related to intraplque hemorrhage or lipid."stiffhess plaque" mainly consisted of fibrous composition. Base on plaque morphological feature ,ratio of exactness by ultrasound was 60.7%. Plaques were classified into heterogeneity and homogeneity.Ulcer on surface of plaque was ofen correlation with intraplque hemorrhage,and susceptible to stroke or transient ischemi attack (TIA) .Magnetic resonance (MR) has emerge...
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