Plaque calcification

Driessens FC, Borggreven JM, Verbeeck RM, van Dijk JW, Feagin FF On the physico-chemistry of plaque calcification and phase composition of dental calculus. J Periodontal Res 1985 20 329-336. 

X-rays in mammography technique and CT are able to detect calcifications of Peyronie plaques and to determine the degree of plaque calcification (Andresen et al. 1998). Non-calcified plaques, however, cannot be shown accurately. The information gained by these methods does not support the use of ionizing radiation for this purpose (Fornara and Gerbershagen 2004). 

The calcification of atherosclerotic plaques may be induced by osteopontin expression, since osteopontin is a protein with a well-characterized role in bone formation and calcification. Vascular smooth muscle cell migration on osteopontin is dq endent on the integrin av 33 and antagonists of av 33 prevent both smooth muscle cell migration and restenosis in some animal model [8]. 

In contrast to the formation and calcification of bones, vitamin K seems to lower the risk of aortic calcification. The mechanisms for these antagonistic effects is not known but a participation of osteocalcin (expressed in artherosclerotic plaques) as well as of matrix Gla protein (MGP) are discussed. In addition, the vitamin K epoxide reductase complex seems to be involved [5]. 

Atherosclerosis is main cause of cardiovascular deaths. It is characterized by a localised plaque in the intima and is composed of cholesterol esters, deposition of fibrous proteins and calcification. These plaques may narrow the arterial lumen and can cause distalischemia. The coronary and cerebral circulation are main sites of atherosclerosis. Raised levels of VLDL, LDL... 

Casscells W, Hassan K, Vaseghi MR et al. Plaque blush, branch location, and calcification are angiographic predictors of progression of mild to moderate coronary stenoses. Am Heart J 2003 145 813-820. 

Foam cells accumulate, releasing growth factors that stimulate proliferation of smooth muscle and calcification of plaque. 

Operator dependent so requires training, skill and experience to ensure accuracy of and consistency in measurement of stenosis Plaque or peri-arterial calcification causes difficulty in interpretation... 

Diseases of elastic tissue are few compared with those that affect collagen, and in these destruction of preformed elastic fibers appears to occur only in localized areas, particularly in the walls of blood vessels and in the skin. In arteriosclerosis loss of elasticity and breakdown in the structure of the elastic elements in the media of arteries is accompanied by calcification of the media and the development of calcified plaques in the intima. Since calcification of the media may be seen to occur without the development of atheromata, it is thought that this change may be associated in the first place with age. Other age-related changes looked for have been changes in the gross content of elastin in the media and changes in the amino acid... 

The site of deposition of calcium in the aging human aorta has been studied more closely by Weissman and Weissman (1960). The gross calcification in the atherosclerotic plaques of the intima of the aging aorta is immediately obvious (Duff and McMillan, 19. )1) and appears to have little connection with the elastic structures. On the other hand, apparently independently of the development of plaques, progressive deposition of calcium takes place in the media with advancing age. It is important to know if this calcification of the media, which evidently leads to loss of elasticity, is directly associated with elastin rather than collagen or. some other components of the elastic tissue. 

When the calcium plaque is thick, it can be removed by scraping with a scalpel or by performing a superficial keratectomy. Other reported methods include the use of a diamond burr, neodymium-yttrium aluminum garnet (Nd YAG) laser, lamellar keratoplasty, and PTK. A recent treatment option described the combined use of superficial lamellar keratectomy, NaEDTA chelation, and amni-otic membrane transplantation. In this procedure the calcific lesions were treated with NaEDTA and a blunt superficial lamellar keratectomy was performed. Once a smooth ocular surface was achieved, an amniotic membrane was transplanted to replace the excised epithelium and stroma. The procedure resulted in the... 

Pleural abnormalities Abnormal or diseased changes occurring in the pleura. Pleural abnormalities associated with exposure to asbestos include pleural plaques, pleural thickening or calcifications, and pleural effusion. 

The fact that plaque is a region in the mouth relatively free from salivary inhibitors is probably one reason why calcification, leading to calculus formation, is associated with plaque. A second reason is the presence of certain bacteria that calcify, e.g. Corynebacterium (formerly Bacterionoma) matruchotii and S. sanguis I/II (more recently S. gordonii). The former bacterium contains cell wall components that can nucleate crystal growth [44, 45, 73], whilst the latter bacterium can metabolise basic amino acids, [74] and thereby, locally raise pH, which favours calcium phosphate precipitation. 

In contrast to angiography, IVUS provides quantitative information from within the vessel on diameter, circumference, luminal diameter, plaque volume, and percent stenosis. Qualitative information regarding the amount of plaque elevation, plaque composition (e.g., calcific, fibrous, or fatty plaque), and the presence of plaque versus thrombus, thrombus versus tumor, and aneurysm and hematoma can be provided with IVUS. IVUS is also used as a therapeutic adjunct with PTCA, atherectomy, stent or graft placement, and fibrinolysis, although routine use may not be justified. These combination procedures may be monitored in real time as the procedure (e.g., atherectomy) is being performed. 

Hollenhorst plaque—Cholesterol emboh that usually dislodges from the carotid arteries, or calcific fragments from a stenosed aortic valve that can be visualized on a retinal exam. 

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