Case report of anomalous vertebral artery from common carotid artery with C4 entry and aberrant right subclavian artery

Introduction and importance: Anomalous origin of the vertebral artery from the common carotid artery (VA-CCA), particularly when combined with an aberrant right subclavian artery (ARSA) and a high (C4) transverse foramen entry, represents an exceptionally rare congenital vascular variant. This complex anatomy poses significant risks of iatrogenic injury during endovascular interventions and anterior cervical spine surgery. Case presentation: A 62-year-old male presented with persistent dizziness. Comprehensive computed tomography angiography (CTA) and digital subtraction angiography (DSA) revealed a unique combination of anomalies: the right vertebral artery originating from the right common carotid artery, entering the transverse foramen at the C4 level, and a retroesophageal ARSA. The patient was managed conservatively with symptomatic resolution and received extensive counseling regarding his anatomy. Clinical discussion: The incidence of VA-CCA is approximately 0.18%. Its association with ARSA and a high cervical entry point creates an elongated, mobile cervical segment with an acute origin angle. This increases the risk of vascular injury during catheterization and anterior surgical approaches to the C4-C6 levels. Pre-procedural recognition via advanced vascular imaging, such as CTA with 3D reconstruction, is crucial for preventing catastrophic complications. Conclusion: This case underscores the critical importance of recognizing this rare vertebral artery anomaly complex. Accurate pre-operative imaging diagnosis and thorough patient counseling are essential for procedural safety planning in patients undergoing neck interventions.