Anatomical and morphological variations of the basilar artery associated with cerebral circulation changes

Abstract: The basilar artery (BA) is one of the main vessels that supplies oxygen rich blood to the brain and it plays a
very important role in cerebral circulation. It is formed by the union of the left and right vertebral arteries at the junction between the medulla oblongata and the pons, near the abducens nerve (CN VI) The vertebrobasilar system is a major blood supply route to the posterior part of the brain, and variations in the basilar artery (BA) may affect blood flow and contribute to neurological symptoms or ischemic events. Aim: This study aimed to assess how often anatomical variations of the BA occur according to sex and age, to measure BA diameter, and to evaluate theiir possible clinical relevance in patients with different neurological and traumatic conditions. Materials and Methods: A retrospective study was conducted on 60 patients (25 women, 41.67% and 35 men, 58.33%) with a mean age of 45.0 ± 12.0 years. Patients were examined at the Clinical Hospital Tetovo over a one-year period. CT, MRA, and Doppler ultrasound were used to evaluate the basilar artery. Measurements were taken and classified as normal, hypoplasia
(<2 mm), or dolichoectasia (>4 mm). Data were analyzed using SPSS v26. Results: Normal BA morphology was the most common finding in both sexes, especially in males (74.3%) compared
to females (64%). Hypoplasia was more frequent in females (32%) than males (17.1%), while dolichoectasia was slightly more common in males (8.6%) than females (4%). In hypoplastic arteries, diameters ranged from 1.80 to 1.95 mm, while in dolichoectasia they exceeded 4.0 mm. Overall, the findings showed noticeable sex-related differences and were in line with previous studies. Conclusion: Anatomical variations of the basilar artery are relatively common and may influence blood flow in the posterior circulation. Recognizing these changes early through modern imaging techniques is important for better diagnosis, risk evaluation, and clinical decision-making