Three-dimensional (3-D) vertical computed tomography angiogram (CTA) showing a left internal carotid artery stenosis with severe calcification.
(A) A (3-D) computer visualization showing the side of the vessel. The medium gray is blood inside the vessel; the bright white is a large calcium deposit.
(B) A single slice through the carotid artery showing the normal vessel diameter at the top and the bottom of the image, with marked narrowing in the middle.
Images C and D are cross-sections of the vessel shown horizontally and viewed from above.
(C) Carotid artery stenosis (circled) with severe calcification. Only the small medium gray dot towards the top of the circle is flowing blood (the rest is plaque), with the bright white crescent and dots being calcium deposits.
(D) Same image as C, without the vessel circled.