INTRAVASCULAR ULTRASOUND IMAGING OF PERIPHERAL ARTERIES AS AN ADJUNCTTO ATHERECTOMY - PRELIMINARY EXPERIENCE

12 atherosclerotic lesions in nine patients, including four restenoses after balloon angioplasty, were treated by atherectomy under the guid ance of intravascular ultrasound (US). Echogenicities of the plaques a nd morphological alterations in the arterial walls produced by atherec tomy were evaluated. The two-layered appearance of post-angioplasty re stenoses was found to be inner fibrous intimal thickening with prolife ration of smooth muscle cells and outer residual collagen-rich plaque. The deep cut surfaces were shown as concave U-shaped defects. Medial tissues were present in all cases where intravascular US demonstrated the disruption of a thin hyperechoic layer of the internal elastic lam ina. Intravascular US imaging may provide valuable information on the degree, eccentricity and histological type of stenosis, the presence o f calcification before atherectomy, and on the extent of excision and the morphological changes in the arterial wall after atherectomy.