Radiographic and histological studies of calcification in the media of muscular-type arteries

Abstract

To learn about the process of calcification in the media of muscular-type arteries, the authors used light and electron microscopy to examine a total of 77 femoral and external iliac artery samples. In addition, 33 femoral arteries were examined by plain radiography. These observations yielded the following results: 1. The calcification of the femoral arteries were radiographically detected in patients who were over 60 years old, and were then divided into two types: a long-axis type calcification and a patchy type calcification. The former was extended along the arterial wall and was suggestive of medial calcification, and the latter was suggestive of intimal calcification as seen under light microscopy. 2. Calcium was distributed in two patterns: a media-type in which calcium accumulated in the extracellular matrix of the media, and an internal elastic lamina (IEL)-type, in which calcium deposition spread around a calcified IEL. 3. Scanning electron microscopy revealed various-sized granules on the extracellular matrix of the media as well as on the IEL. Using with X-ray EDS micro-analysis, calcium and phosphorus were detected in these depositions. 4. Calcium deposition of the media, first noted in the 40-year-old, became more exaggerated in size and extent with individual sample age, and typical Mönckeberg's arteriosclerosis was present total in a total of 9.1% of examined cases over 60 years old. These findings suggested that the calcium deposition in the arterial media was a normal physiological process with aging, and Mönckeberg's arteriosclerosis was initiated on the basis of medial calcium deposition, occuring at around 60 years old.