Click on image to view larger version.

Figure 1 Representative ultrasound images of atherosclerotic carotid plaques with low and high calibrated integrated backscatter (IBS) values. The red dotted line indicates region of interest in the plaque (intima-media complex), and the blue dotted line indicates region of interest in the adventitia using a manual outline definition mode. (Left) Low IBS plaque is identified by arrows. The calibrated IBS value and maximum intima-medial thickness (IMT) of this plaque are –17.6 dB and 2.1 mm, respectively. (Right) High IBS plaque is identified by arrowheads. The calibrated IBS value and maximum IMT of this plaque are –9.1 dB and 2.3 mm, respectively. CCA = common carotid artery; ICA = internal carotid artery.