Figure 1

Cross-sectional T2 maps of carotid arteries with atherosclerotic plaques and relative classification of main plaque components. The colour scale indicates T2 relaxation times in ms with blue corresponding to LRNC (T2<40ms), cyan to normal media or fibrous tissue (T2=40-70ms) and red to haemorrhage (long T2). Yellow represents T2 values that may be caused by incorrect overestimation or by partial volume averaging in the presence of haemorrhage. Calcification has very low proton density that produces insufficient SNR and appears black on the T2 maps. Using a semi-automated method, T2 maps were segmented into 4 tissue classes represented by the different colours at the bottom.