MEASUREMENTS OF FLOOD FLOW VELOCITY BY ME ANS OF TCD AND TCCD

The aim of the present study was to clarify, by means of transcranial colour-coded duplex sonography of the basilar artery, whether there ar e changes in basilar artery blood flow in patients with acute inner ea r disturbances and whether the flow in the basilar artery is affected by acoustic stimuli in such patients and in normal, healthy controls. Method: Basilar artery blood flow velocity was measured in 52 patients with severe inner ear impairment over a period of tow weeks by means of conventional transcranial Doppler sonography and transcranial colou r-coded duplex sonography. The same measurements were carried out in 4 5 healthy control subjects. At the end of the two week period, both pa tients and controls were exposed to 70-dB noise, with basilar artery f low evaluated before and during exposure. The basilar artery Doppler c urves were analysed for systolic flow velocity, end-diastolic flow vel ocity, resistance index (Pourcelot) and pulsatility index (Gosling). R esults: During the first two days of the study, the basilar artery res istance index and pulsatility index were significantly (p < 0.001) hig her in patients than in controls. During noise exposure, both patients and controls showed significant (p < 0.01) increases in these indices . Conclusion: This study shows that temporary increases in the basilar artery resistance index and pulsatility index are found both in the a cute phase of inner ear disease and during exposure to noise.