A Systematic Review and Meta-analysis of Prevalence of Common Carotid Artery Branching Variations at Different Vertebral Levels and Methodological Approaches

Abstract Background and Objectives: Considerable variability exist in common carotid artery branching (CAB) level. The objective of this review and meta-analysis was to determine the overall prevalence of CAB in relation thyroid cartilage or in relation to vertebral levels from cadaveric and radiological studies. Methodology: All published original research articles reporting CAB variations were included. The Embase, PubMed, and Google Scholar search string used was “Common carotid artery branching”/syn OR “Carotid artery bifurcation”/syn. A systematic review and meta-analysis was conducted according to the PRISMA guidelines. Random-effects models were used to estimate pooled prevalence, and heterogeneity was assessed using I 2 and τ² statistics. Results: Overall, 2045 published articles were identified, and 43 studies were included in this review and meta-analysis. Twenty-eight cadaveric and 4 computed tomography angiography (CTA) studies reported CAB with anterior landmarks. 7 CTA studies and 4 cadaveric studies reported CAB with posterior landmarks. Pooled prevalence of CAB at the thyroid cartilage was 64.7% (95% confidence interval [CI]: 58.7%–70.3%), higher bifurcation was 29.4% (95% CI: 24.2%–35.2%), and lower bifurcation was 6.7% (95% CI: 5.0%–8.9%). For posterior landmarks, the most common levels were C3 (33.2%) and C3–C4 (25.1%), and C4 (22.8%), Substantial heterogeneity was observed ( I 2 >70%), reflecting methodological and population differences. Egger’s test suggested small-study effects for lower bifurcation reporting. Conclusion: This meta-analysis demonstrated that CAB most commonly occurs at the level of the thyroid cartilage (64.7%), with 29.4% showing higher positions, while posterior landmark analysis revealed predominance at C3–C4 (81%). These findings emphasize the clinical relevance of higher bifurcation during surgical and interventional procedures.