Window settings for the study of calcified carotid plaques with multidetector CT angiography.

SUMMARY CT angiography (CTA) shows high sensitivity in detecting calcified plaques, but sometimes a bias in the exact quantification of stenosis degree occurs, mainly caused by the high linear attenuation coefficient of the calcified plaques. The purpose of this technical study was to evaluate the most appropriate CT window parameters for the assessment of calcified plaques stating which of them can provide the best inter-observer agreement. Scatter-plots and regression results showed the correlation between both width and level respectively depending on intraluminal Hounsfield units (HU) value (width = intraluminal HU x 2.07; level = intraluminal HU x 0.72). Obtained data indicated that the presence of different stenosis degrees did not modify visualization parameters.