Elongated Internal Carotid Arteries in Patients with Severe Carotid Artery Stenosis

Objective: This study aimed to investigate the risk factors and asymptomatic cerebrovascular diseases associated with elongated internal carotid arteries (ICAs) and the relationship between ICA elongation and severe carotid artery (CA) stenosis. Methods: We evaluated risk factors for stroke and magnetic resonance imaging (MRI) findings in patients with severe CA stenosis compared with people without neurological disorders who underwent brain screening (controls). On magnetic resonance angiography (MRA) images, we measured the longest distance, defined as the ICA distance, from the most distant anterior wall of the cervical ICA at the site of bending or kinking to the line between the origin of the external CA and the anterior protrusion of the ICA near the petrosal bone. We retrospectively compared various asymptomatic findings, including cerebral microbleeds, lacunar infarctions, and deep white matter hyperintensities (WMHs), between participants with an ICA distance ≥ 1.2 cm vs. < 1.2 cm. The prevalence of findings and stroke risk factors were compared using multivariate logistic regression models. Results: We evaluated 53 patients (70.0 ± 8.1 years old, nine female) with severe CA stenosis treated by CA stenting and 400 controls (63.0 ± 9.2 years old, 227 females). Multivariate analyses showed that ICA distance ≥ 1.2 cm was associated with age ≥ 65 years (odds ratio (OR) = 1.8, p < 0.01), severe deep WMHs (OR = 2.0, p = 0.02), and severe CA stenosis (OR = 0.17, p < 0.01). Conclusion: ICA elongation, measured by ICA distance, was positively associated with age and deep WMHs and negatively associated with severe CA stenosis.