Carotid Plaque Imaging: Strategies beyond Stenosis

Atherosclerosis at the carotid bifurcation in the neck is common and the result of turbulent hemodynamics in the bulb. Carotid bulb plaques cause disabling strokes. Carotid vessel wall imaging characterizes the atherosclerotic plaque, documents disease progression, and assesses lesion severity by plaque morphology in addition to the degree of stenosis. This in turn optimizes treatment selection for the individual patient. The aim of vessel wall imaging in patients of stroke is to distinguish stable plaques that may be conserved with best medical management from unstable or vulnerable plaques that require more aggressive medical treatment, carotid stenting, or carotid endarterectomy. Growing evidence suggests that depending on luminal stenosis measurements alone for management decisions will result in underestimating a number of plaques whose size may be small, but where the plaque morphology is unstable, there is a high likelihood of the patient developing a thromboembolic stroke in the near future. In today's context of aggressive management of even transient ischemic attacks and minor strokes, vessel wall imaging should be particularly performed in cryptogenic strokes without significant luminal narrowing on angiography to identify a subset of patients with nonstenotic but unstable atherosclerotic plaques that may be covert etiologies of stroke. If patients receiving the best medical management have recurrent strokes on the same side as a carotid plaque with "vulnerable" plaque features, they may deserve surgical or endovascular intervention even if they do not meet the conventional stenosis thresholds. Improved techniques for stroke imaging and consequent management have a remarkable effect in decreasing individual and public health burdens.