Abstract
Objective: The vertebrobasilar artery (VBA) exhibits substantial inter-individual variation that must be considered in diagnosis and surgical planning. We conducted three-dimensional reconstruction of the bilateral VBA based on head and neck computed tomography angiography (CTA) to assess bilateral, individual, age-dependent, and sex-dependent differences in anatomical parameters.
Methods: Individual three-dimensional models of the VBA and skull were constructed and morphology evaluated based on head and neck CTA data from 199 adults. According to morphological and anatomical variation, the VBA was divided into three types: balanced, L, and S. The diameters and lengths of basilar and bilateral vertebral artery intracranial segments as well as VBA blending length, and bilateral distances of the vertebral arteries moving up the atlas were measured and statistically compared.
Results The L-type was the most common VBA morphology, and anatomic type distribution differed significantly by age (P < 0.05). Vertebral artery diameter was 3.34±0.68 mm on the left side and 3.09±0.71 mm on the right side, while bending length was 5.62±3.35 mm on the left and 4.94±3.41 mm on the right side. Balanced basilar arteries measured 3.41±0.61 mm in diameter, 2.83±0.33 cm in length, and 2.55±2.45 mm in bending length. The L-type basilar artery measured 3.48±0.71 mm in diameter, 3.06±0.44 cm in length, and 2.78±0.37 mm in bending length.Finally, S-type basilar arteries measured 3.84±0.86 mm in diameter, 3.38±0.61 cm in length, and 3.67±4.39 mm in bending length. The distance traveled by the vertebral artery across the atlas differed significantly between left and right sides as well as between males and females (P < 0.05).
Conclusions The VBA can be accurately reconstructed in three-dimensions using head and neck CTA. These reconstructions confirmed the basic anatomic types proposed previously and further identify bilateral, sex-dependent, and age-dependent differences.