Illustration comparing a normal blood vessel and partially blocked vessel due to atherosclerotic plaque. Notice the enlargement & absence of much luminal narrowing. Because artery walls enlarge at locations with<unk> , detecting<unk>  before death and autopsy has long been problematic at best. Most methods have focused on the openings of arteries; while these methods are highly relevant, they totally miss the<unk>  within the arterial lumen. Historically, arterial wall fixation, staining and thin section has been the gold standard for detection and description of<unk> , after death and autopsy. With special stains and examination, micro calcifications can be detected, typically within smooth muscle cells of the arterial media near the fatty streaks within a year or two of fatty streaks forming. Interventional and non-interventional methods to detect atherosclerosis, specifically vulnerable plaque (non-occlusive or soft plaque), are widely used in research and clinical practice today. Carotid Intima-media thickness Scan (CIMT can be measured by B-mode ultrasonography) measurement has been recommended by the American Heart Association as the most useful method to identify atherosclerosis and may now very well be the gold standard for detection. Intravascular ultrasound is the current most sensitive method detecting and measuring more advanced<unk>  within living individuals, but has had limited applications due to cost and body invasiveness. CT scans using state of the art higher resolution spiral, or the higher speed EBT, machines have been the most effective method for detecting calcification present in plaque. However, the<unk>  have to be advanced enough to have relatively large areas of calcification within them to create large enough regions of ~130 Hounsfield units which a CT scanner's software can recognize as distinct from the other surrounding tissues. Typically, such regions start occurring within the heart arteries about 2–3 decades after<unk>  start developing. The presence of smaller, spotty plaques may actually be more dangerous for progressing to acute myocardial infarction. Arterial ultrasound, especially of the carotid arteries, with measurement of the thickness of the artery wall, offers a way to partially track the disease progression. As of 2006, the thickness, commonly referred to as IMT for intimal-medial thickness, is not measured clinically though it has been used by some researchers since the mid-1990s to track changes in arterial walls. Traditionally, clinical carotid ultrasounds have only estimated the degree of blood lumen restriction, stenosis, a result of very advanced disease. The National Institute of Health did a five-year $5 million study, headed by medical researcher Kenneth Ouriel, to study intravascular ultrasound techniques regarding atherosclerotic plaque. More progressive clinicians have begun using IMT measurement as a way to quantify and track disease progression or stability within individual patients. Angiography, since the 1960s, has been the traditional way of evaluating for<unk> . However, angiography is only motion or still images of dye mixed with the blood within the arterial lumen and never show<unk> ; the wall of arteries, including<unk>  within the arterial wall remain invisible. The limited exception to this rule is that with very advanced<unk> , with extensive calcification within the wall, a halo-like ring of radiodensity can be seen in most older humans, especially when arterial lumens are visualized end-on. On cine-floro, cardiologists and radiologists typically look for these calcification shadows to recognize arteries before they inject any contrast agent during angiograms. Classification of lesions * Type I: Isolated macrophage foam cells * Type II: Multiple foam cell layers * Type III: Preatheroma, intermediate lesion * Type IV:<unk>  * Type V: Fibroatheroma * Type VI: Fissured, ulcerated, hemorrhagic, thrombotic lesion * Type VII: Calcific lesion * Type VIII: Fibrotic lesion
Atheroma
Askin's tumor
Lymphangioma
Hemangioma
Nuchal fibroma
Chorangioma
Ganglion cyst
Baker's cyst