Bilateral Pentafurcation of the Common Carotid Arteries: A New Anatomic Variant

Purpose The Common Carotid Artery (CCA) is understood to bifurcate at the level of the upper border of the thyroid cartilage into the internal carotid artery (ICA) and external carotid artery (ECA). Variations on these branching patterns have been reported and several classification systems have been proposed. Pentafurcations at the carotid sinus are very rare, with no previous mention of bilateral occurrences found in the literature. The clinical importance of understanding the variability in carotid vasculature is paramount in both radiologic and surgical specialties, and for predicting the impact of carotid artery anomalies on the pathophysiology of carotid atherosclerosis. Methods During the first-year medical student anatomy course at Kansas City University, dissection of the deep anterior neck region was performed on an 84-year-old male formalin fixed cadaver with limited past medical history. Results A bilateral carotid artery pentafurcation was identified. In addition to typical ICA and ECA branches, the carotid sinus bilaterally produces the superior thyroid artery (STA), anterior pharyngeal artery (APA) and occipital artery (OA). Conclusions This case presents a previously unreported bilateral carotid artery pentafurcation. Understanding the variability possible in head and neck anatomy is paramount in critical during surgical and radiologic procedures, and explaining the pathogenesis of certain vasculopathies.