Takeuchi M, et al. - In this observational study, researchers assessed the link between the longitudinal change in basilar artery (BA) diameter (ΔBA) and cardiovascular events (CVEs) as well as the time course of the BA diameter in a cohort of Japanese participants with vascular risk factors. Using T2-weighted images, they assessed the short axis of the BA diameter at the midpons level. Cerebral small-vessel disease, lacunars, and white matter hyperintensities were assessed. Using time-dependent Cox proportional hazards model, the link between ΔBA and CVEs was assessed in 493 patients, with adjustment for age, sex, vascular risk factors, and magnetic resonance imaging parameters. Using linear regression analysis, they evaluated the longitudinal ΔBA in 164 patients who had long-term follow-up magnetic resonance imaging. The mean follow-up was of 8.7 years, during which, CVEs were reported in 105 patients. Findings revealed an increase in BA diameter over time (excluding the patients with fetal-type circle of Willis), and an inverse relation of ΔBA to the incidence of CVEs was evident.