Clinical assessment of atherosclerotic lesions: emerging from angiographic shadows.

In the mid to late 1800s, the light microscopic features of atherosclerosis were discovered as Virchow and others used techniques that were novel at the time for paraffin embedding, sectioning, and staining of tissues.1 From then until the past few years, detailed characterization of atherosclerotic lesions has been limited to autopsied or excised tissues, which display only a single time point per specimen. Today, the goal of visualizing and characterizing the diseased arterial wall in living patients has become a reality with the use of several techniques. In this issue of Circulation, Cai and colleagues2 demonstrate that magnetic resonance can provide a living “biopsy” of carotid atherosclerotic plaques. Preoperative MRIs correlated well with paraffin section histology of endarterectomy specimens, classified by criteria of the Committee on Vascular Lesions of the Arteriosclerosis Council.3