Fig 2. Stenotic value of internal carotid artery stenosis (ICAS) depends on projection view.

(A and B) Anterior-posterior projection of power-mode 3D reconstructed ICAS; original lumen is also reconstructed and visualised in yellow (A). (B—D) Stenotic value of ICAS assessed as distal cross-sectional area reduction percentage (93%) does not change since it is not affected by rotation or tilting. By contrast, clockwise rotation of ICAS results in a decrease of stenotic value assessed as distal diameter reduction percentage from 82% (B) respectively 83% (C) to 72% (D). Smallest luminal diameter is marked with filled arrowhead while distal luminal diameter is marked with open arrowhead. Asterisk indicates origin of external carotid artery (not shown). CCA common carotid artery. Scale bar: 1 cm.