Cerebral ischemic disease and morphometric analyses of carotid plaques

Atherosclerotic carotid plaque morphology and especially, intraplaque hemor rhage are assumed to be related to neurological symptoms. Most researchers have only investigated the incidence of intraplaque hemorrhage in symptomat ic and asymptomatic patients. In the present study, the amount of intraplaq ue hemorrhage is determined in carotid endarterectomy specimens from 33 sym ptomatic and 14 asymptomatic patients that caused >70% luminal stenosis. Th e plaque components (fibrosis, lipids, intraplaque hemorrhage, calcificatio n, and intraluminal thrombosis) were quantified as a percentage of the tota l plaque volume. A high incidence of intraplaque hemorrhage was found in bo th the symptomatic (94%, 31/33) and asymptomatic (71%, 10/14) patients. The amount of intraplaque hemorrhage was very small within the plaques of the symptomatic (0.39% +/- 0.70%) and asymptomatic (0.37% +/- 1.12%) patients. The plaques of the symptomatic patients contained more fibrosis than lipids (45.62% +/- 14.99% and 20.45% +/- 21.45%, respectively), as did the plaque s of the asymptomatic patients (42.51% +/- 15.28% and 15.46% +/- 15.22%, re spectively). Finally, intraluminal thrombosis and calcification were rare. We conclude that the amount of intraplaque hemorrhage was very small and th erefore question its direct role in the development of neurological symptom s. In general, the "unstable" plaque contained more fibrosis than lipids.