Vertebral artery volume flow in human beings☆

Abstract 

Background: A number of studies have investigated vertebral artery flow velocity. Because perfusion relates to the volume of blood flowing through the vessel, this parameter is of great importance when vertebral artery hemodynamics are investigated. We could not find any such Doppler studies in the literature, possibly because of known errors with previous techniques. New advanced color-coded duplex sonography has since been validated and may be used with confidence for volume flow investigations. Objective: To use advanced color-coded duplex sonography to investigate volume flow through the vertebral arteries during cervical rotation, as well as before and after spinal manipulation therapy. Design and Setting: A randomized controlled study at a university hospital vascular laboratory. Participants: Twenty university students. Results: Volume blood flow through the vertebral arteries does not change with cervical rotation or after spinal manipulation therapy. Conclusion: This appears to be the first in vivo Doppler study on human vertebral artery volume blood flow. Our results indicate that in symptom-free subjects there is no change in vertebral artery perfusion during rotation in spite of significant changes in flow velocity. This finding, as well as the observed changes in flow velocity reported by others, may be explained by a positional change in the vertebral artery diameter. In addition, we have investigated volume blood flow in the vertebral arteries before or after spinal manipulation therapy but found no significant changes. (J Manipulative Physiol Ther 1999;22:363–7)

Keywords:  Volume Flow, Vertebral Artery, Rotation, Chiropractic Manipulation