Association Between Carotid Artery Plaque Volume, Composition, and Ulceration: A Retrospective Assessment With MDCT
AJR July 2012 vol. 199 no. 1 151-156
Luca Saba1, Roberto Sanfilippo2, Stefano Sannia1, Michele Anzidei3, Roberto Montisci2, Giorgio Mallarini1 and Jasjit S. Suri4,5
OBJECTIVE. The purpose of this study was to evaluate the relationship between MDCT angiography–assessed carotid artery plaque volume and composition and the presence of ulceration.
MATERIALS AND METHODS. Seventy consecutive patients (46 men and 24 women; mean age, 63 years; age range, 42–81 years) were studied using MDCT and were retrospectively analyzed. Component types of the carotid plaque were defined according to attenuation value ranges (lipid, < 60 HU; fibrous tissue, 60–130 HU; and calcification, > 130 HU). The plaque volumes of each component were calculated. Statistical analysis was performed using the receiver operating characteristic (ROC) statistic and Wilcoxon signed rank test to evaluate the association between the presence of ulceration and specific plaque components and their volume.
RESULTS. Eighteen carotid arteries were excluded, and 16 ulcerated plaques were detected in the remaining 122 carotid arteries. Wilcoxon and ROC curve analysis showed a statistically significant association between increased relative lipid volume and ulceration (p = 0.0001; area under the ROC curve, 0.916). The total volume of the plaque did not show an association with the presence of ulceration (p = 0.0526).
CONCLUSION. The results of our retrospective study suggest that there is no correlation between total carotid atherosclerotic plaque volume and ulcerations, whereas plaque relative lipid volume (using attenuation of < 60 HU) is associated with the presence of ulceration. This finding could indicate vulnerable plaques and increased risk for cerebrovascular events.