Intracranial carotid artery calcification patterns and ischemic stroke: a novel marker for stroke etiology?

Intracranial carotid artery calcifications (ICAC) are a common finding on non-contrast computed tomography (NCCT) and have been associated with an increased risk of ischemic stroke. Intimal, medial, and mixed subtypes of ICAC have been recognized, but no data are available about the association between ICAC patterns and stroke etiology. The aim of our study was to investigate the association between ICAC patterns and etiological subtypes of ischemic stroke. We retrospectively analyzed a single center cohort of patients admitted for ischemic stroke with known etiology. Patients with a first ischemic stroke with lacunar, cardioembolic or atherothrombotic large artery disease etiology were included. Each carotid artery was evaluated separately on NCCT scans to define the ICAC pattern. The association of ICAC patterns and stroke etiology was investigated using two logistic regression models adjusting for confounders. A total of 300 patients were included in the analysis, mean age 78 years (+-10), 158 (53%) female, median NIHSS 6 (IQR 9). Prevalence of medial, intimal, and mixed calcification was: 73%, 17% and 11% in cardioembolic stroke, 66%, 25% and 9% in large artery atherosclerosis stroke and 37%, 44% and 19% in lacunar stroke (p < 0.001). After adjustment for confounders, intimal pattern (OR = 2.14; 95%CI = 1.07–4.30), and medial pattern (OR = 0.33; 95CI%=0.16–0.67) remained independently associated with lacunar stroke etiology. In conclusion, our study suggests that intimal ICAC pattern is associated with lacunar stroke, and, if validated in further studies, it may serve as a marker for lacunar stroke etiology.