Anatomical Characteristics of the Vertebral Artery Examined with CTA

Abstract

Objectives: The vertebral artery and its branches are target of arteriographic investigations, ultrasound and Doppler visualization, MRI and CT imaging in many contemporary diagnostic procedures. The aim of this study was to examine vertebral artery anatomy, as well as its variations, and to emphasize their clinical importance. Material and Methods: We examined radiographs of patients who had CT angiography undertaken for a variety of clinical reasons, performed as a part of their medical treatment at the University Clinic for Radiology in Skopje, R. Macedonia. The study population included 103 patients, 58 male and 45 females, age range from 25-82, mean age 58.4 years. Results: The left vertebral artery arose from the subclavian artery in 94.17% and the right vertebral artery had origin from the subclavian artery in 99.02%. Variable origin from the aortic arch was noticed in 5.82% of the patients of the left side. In one patient (0.97%) we found atypical arisen of the right vertebral artery from the right common carotid artery in combination with an aberrant right subclavian artery. The diameter of the left vertebral artery at its origin was in range between 1.63 – 4.80 mm, mean 3.33 ± 0.76 mm, and of the right vertebral artery was from 1.60 – 5.0 mm, mean 3.20 ± 0.74 mm. Straight course of the left and right vertebral artery was noticed in 69.90%, 70.87%, respectively. Tortyosity of the left and right vertebral artery was observed in 30.09% and 29.12%, respectively. The left vertebral artery entered the C6 transverse foramen in 92.23% and the right vertebral artery in 94.17%. Abnormal entrance was observed in 7.76% of the left vertebral artery and in 5.82% of the right vertebral artery, with entrance into the C4, C5 or C7 transverse foramen. Conclusion: Although anatomically interesting, an awareness of the vertebral artery anatomy and variations is clinically important. A precise understanding of the vertebral artery anatomy is fundamental for planning and performing endovascular procedures and neuro-interventions, as well as for the accurate interpretation of ischemic areas.