Transcranial measurement of blood velocities in the basal cerebral arteries using pulsed Doppler ultrasound: velocity as an index of flow

Kirkham, F.J., Padayachee, T.S., Parsons, S., Seargeant, L.S., House, F.R. and Gosling, R.G. (1986) Transcranial measurement of blood velocities in the basal cerebral arteries using pulsed Doppler ultrasound: velocity as an index of flow. Ultrasound in Medicine and Biology, 12 (1), 15-21. (doi:10.1016/0301-5629(86)90139-0).

Abstract

Blood velocities have been measured transcranially, at small Doppler angles, in the middle cerebral artery of normal volunteers. Cerebral blood flow was changed by varying carbon dioxide tension. In four volunteers, the relationships between arterial pCO₂ and percentage change in intensity weighted mean, median, and maximum Doppler-shifted frequencies in the internal carotid and middle cerebral arteries were linear with slopes of 2.5 and 2.8% per mm Hg change in pCO₂. In 38 volunteers, the relationship between end-expiratory pCO₂ and time-averaged maximum Doppler frequency was linear over the range of pCO₂ 20-60 mm Hg with slopes of 2.5 and 2.9 percentage change per mm Hg, for internal carotid and middle cerebral, respectively. These results are very similar to those reported using direct methods of measuring cerebral blood flow. As the transcranial Doppler method is reproducible, this indicates that changes in middle cerebral blood velocity may be used to monitor changes in flow.

This record has no associated files available for download.

Contributors

Author: F.J. Kirkham

Download statistics