The advent of advanced multi-detector computerized tomography has positioned CTA as the most definitive noninvasive method for evaluating carotid and cerebral artery stenosis. Studies comparing CTA with conventional carotid angiography show sensitivities and specificities of nearly 100% for CTA.

When compared with contrast-enhanced magnetic resonance angiography (MRA), the strength of CTA lies in its ability to better distinguish a severe stenosis from total occlusion due to its superior resolution. Although conventional angiography has very high resolution, its usefulness is limited by its invasive nature and inability to evaluate plaque morphology.

Carotid arteries
These two large arteries, one on each side of the head, carry blood to the head and that divide into an external branch supplying the neck, face, and other external parts, and an internal branch supplying the brain, eye, and other internal parts.