Three-dimensional ultrasound carotid artery longitudinal view in clinical trials [40]. Both baseline and follow-up 3D images, constructed from the set of 2D frames, were examined simultaneously to visually match the bifurcation (BF) points in both images by an operator blinded to time point and treatment. Each 3D US image was manually segmented starting from the bifurcation point extending into around 10–15 mm of common carotid artery (CCA) and about 10 mm into internal carotid artery (ICA) at 1 mm interval perpendicular to the artery axis; refer to Figure 3. This study was only carried out on the CCA, since the focus was on stroke risk.