Anatomy and Variations of the Vertebrobasilar System Examined with Digital Substraction Angiography

Abstract

The posterior circulation of the brain constitutes the vertebrobasilar system and its branches, which are responsible for about 30% of the brain blood supply. The aim of this study was to examine the anatomy and variations of vertebrobasilar system with DS angiography. We examined radiographs of 55 patients who had DS angiography undertaken for a variety of clinical reasons, performed as a part of their medical treatment at the University Clinic for Radiology in Skopje. This study was approved of the Macedonian Ethical Committee. The study population included 27 male and 28 females, age range from 18-79, mean age 51.09 years. The left VA originated from the subclavian artery in 96.36% and in 3.63% had variable origin from the aortic arch. The right VA without exception had origin from the subclavian artery in 100%. Most of the SCA arise from the basilar artery as a single vessel (92.7% on right and 94.5% on left). The most common variations of the SCA were duplication (frequency 3.63% on right and 1.81% on left) and origin from PCA (frequency 3.63% bilateral). Adult configuration of PCA was present in 74.54%; fetal configuration was present in 20% and transitional configuration was present in 5.45% of the patients on the left side. On the right side adult configuration was present in 83.63%; fetal configuration was present in 14.54% and transitional configuration was present in 1.81% of the patients.Through knowledge of the anatomy and variations of the vertebrobasilar system is important to clinicians on daily basis for save performance of diagnostic and interventional procedures in radiology and for surgeons during planning and accomplishing surgical interventions. For the anatomists, the results obtained from this study present valuable teaching material for students and postgraduates.