Unraveling the significance of carotid siphon calcifications: Mechanisms and clinical implications in vascular aging - A narrative review

BACKGROUND AND PURPOSE: Carotid siphon calcifications (CSCs) are frequently overlooked in routine neuroimaging despite their common occurrence. These lesions primarily involve the medial arterial layer, and manifest as diffuse, laminar deposits closely associated with systemic metabolic dysfunction, vascular stiffness, and reduced arterial compliance. A narrative review is timely given the growing recognition of CSCs as potential markers of cerebrovascular vulnerability and vascular aging. OBSERVATIONS: Emerging data associate CSCs with a broad spectrum of adverse outcomes, including brain infarcts, neuroimaging markers of cerebral small vessel disease, cognitive impairment, and increased all‑cause mortality. CSCs also correlate with atherosclerotic burden across multiple vascular territories and with poorer prognosis following cerebrovascular events. Evidence from both high‑income and resource‑limited settings underscores their relevance in populations with elevated cardiovascular risk and limited access to advanced neuroimaging. Despite these insights, major gaps persist regarding the longitudinal evolution of CSCs, their pathogenic mechanisms, and their predictive utility in clinical practice. CONCLUSIONS: Current findings suggest that CSCs may be cost‑effective surrogate markers of vascular aging with potential implications for stroke prevention, risk stratification, and public health planning. Their relevance is particularly notable in settings where cardiovascular risk is high and diagnostic resources are constrained. While the narrative nature of this review together with heterogeneous definitions in imaging methods restrict broader clinical application, strengths of the existing literature include convergent evidence across disciplines and populations, supporting the need for harmonized methodologies and prospective studies to determine the prognostic value of CSCs.