Morphometric Study of the Vertebral Artery and Its Anatomical Variations in the Cervical Spine Using CT Angiography as a Diagnostic Tool: Implications for Cervical Spine Surgery.

Original Article

Abstract

Objective: To evaluate the morphometric characteristics, anatomical variations, origin, dominance, transverse-foramen entry level, and surgically relevant course of the vertebral artery (VA) in the cervical spine using computed tomography angiography (CTA), and to determine the clinical implications of these variations for cervical spine surgery.

Methodology: This Descriptive cross-sectional study was conducted in the Department of Anatomy, Bacha Khan Medical College, Mardan, Pakistan, from January 2024 to January 2025. We evaluated adult cervical CTA examinations for the origin, course, diameter, dominance, transverse-foramen entry level, and V2 and V3 segment variations of both vertebral arteries. We divided the vertebral artery into V1, V2, V3, and V4 segments. Measurements included arterial diameter, distance from the vertebral artery to selected cervical surgical landmarks, transverse-foramen dimensions, and C2-related parameters. We documented a high-riding vertebral artery, unusual transverse-foramen entry, tortuosity, medial migration, and anomalous origin. Data were analyzed using SPSS. We expressed continuous variables as mean ± standard deviation and categorical variables as frequencies and percentages.

Results: We included 120 adult CTA examinations, representing 240 vertebral arteries. The mean age was 48.6±13.2 years, and 72 (60.0%) participants were male. The left vertebral artery was dominant in 58 (48.3%), the right in 43 (35.8%), and 19 (15.8%) had approximately symmetrical vertebral arteries. In most cases, the vertebral artery entered the C6 transverse foramen.

Conclusion: CTA provides detailed vertebral artery anatomy, supporting preoperative assessment before C1–C2 instrumentation, cervical pedicle screws, uncovertebral decompression, and transverse-foramen procedures.