Carotid artery atherosclerosis is not associated with hyoid proximity: Results from a cross-sectional and longitudinal cohort study

Introduction: Cervical internal carotid artery (ICA) atherosclerotic plaque and stenosis is often asymmetric. We hypothesized that hyoid bone proximity to the ICA also may be asymmetric and may increase the risk of traumatic endothelial injury and accelerate atherosclerotic stenosis. Methods: A retrospective cross-sectional and longitudinal cohort design evaluated consecutive adult patients at 3 hospitals who underwent repeat computed tomography angiography (CTA) of the neck 2 calendar years apart (01/2000-07/2017). ICA plaque thickness, luminal stenosis, and their progression over time were compared between side with the nearer hyoid wing (proximal side) to the further side (distal side). Results: Sixty-six patients were included with a median age of 64y (IQR 53-73), 37 (56.1%) female, had a median hyoid-ICA distance of 3.06 mm (IQR 1.27-6.20 mm) and median difference between sides of 2.11 mm (IQR 0.70-3.97 mm). The median plaque thickness was 3.5 mm (IQR 2-4) and median stenosis was 10% (IQR 0-33%). Comparing the proximal to distal side, there was no difference in ICA plaque thickness (median 2.5 mm [IQR 1-4] vs. 3.0 mm [IQR 2-4], p = 0.366) or stenosis (7% [IQR 0-31%] vs. 12% [IQR 0-39%], p = 0.21). After a median follow-up of 1002 days (range 392-3397 days), there was no difference in the change in plaque thickness (0.5 cm [IQR 0-1] vs. 0.0 cm [IQR -0.5-0.5], p = 0.21) or stenosis (0% [IQR -2.5-13%] vs. 0% [IQR -6-5%], p = 0.34) between proximal and distal ICAs. Conclusions: The presence and progression of atherosclerotic plaque and stenosis were unrelated to hyoid-ICA distance in this cross-sectional and longitudinal cohort study.