The stability, and symptomatology, of carotid artery atherosclerotic lesions is now known to depend largely on the histologic compositional makeup of a given plaque.[4], [9] Three of the most studied plaque components are lipid-rich necrotic cores (LRNCs), intraplaque hemorrhage (IPH), and calcification. Both IPH and LRNC confer higher risk of ipsilateral neurologic symptoms and a greater propensity for sudden growth, while calcification is associated with relative stability of plaques.[18], [17]

The sinister manifestations of these high-risk plaque features have spurred numerous recent explorations into the correlation between such components and medication usage. For example, some studies have shown associations between IPH and the use of anticoagulants.[12], [16] Others have demonstrated that LRNCs can stabilize, or even regress, following the initiation of cholesterol-lowering drugs (i.e. statins), sometimes referred to as “delipidation”.[23] Observation of both LRNC and IPH has previously required MRI, since CTA is notoriously poor at differentiating between these features (Fig. 1).

Recently, however, semi-automated software has been introduced for plaque characterization on CTA.[6], [19] Such artificial intelligence-derived programs may offer a way to use CTA to perform in vivo evaluations of LRNC and IPH, an alluring prospect given how commonly CTA is used in stroke imaging. Still, the use of this software as a tool for analyzing LRNC and IPH in the setting of various medication usage remains essentially unstudied. The current study set out to assess whether carotid plaque IPH and LRNC volumes were associated with the use of medications.