The influence of noise on blood flow in the basilar artery (BA) - measurements with transcranial color-coded duplex sonography (TCCD)

Acoustic stimuli are being reported as a cause of changes in resistance in the basilar artery (BA). II was the aim of this study to investigate this e ffect under standardized conditions dependent upon the intensity of the evo king stimulus. Twenty healthy subjects with normal hearing (male/female 14/ 6; mean age 26.4 years) were exposed to 'pink noise: for periods of 2 min a t 75, 85 and 95 dB(A). Parallel to this, the Doppler spectrum of the BA and both the Pourcelor resistance index and the Gosling pulsatility index were measured by means of transcranial color-coded Doppler sonography. In compa rison with the base value (al rest) a significant increase in resistance wa s noted during noise exposure. The noise-induced resistance changes could b e interpreted as a consequence of changes in activity of the various center s of the auditory pathway and cerebral function. Further animal experiments may prove the connection between BA blood flow and resistance and their ch anges depending on different acoustic stimuli or different hearing pathophy siology. (C) 2000 Elsevier Science B.V. All rights reserved.