めまい患者へのTCDの臨床応用

炭酸ガス反応性の検討

抄録

The response of cerebral blood flow to changes in the carbon dioxide partial pressure (i.e., CO₂ reactivity) has been evaluated as a parameter of cerebral perfusion reserve in patients with vertigo by transcranial Doppler ultrasonography (TCD).
We have examined the mean blood flow velocity (FV), and CO₂ reactivity of basilar artery (BA) by TCD. Nine patients with cerebral infarction, 46 patients with vertebrobasilar insufficiency (VBI) (17 vascular VBI and 29 hemodynamic VBI), 29 patients with peripheral vertigo, 46 patients with vertigo of unknown origin and 14 normal subjects were enrolled in this study.
CO₂ reactivity in patients with cerebral infarction and vascular VBI was significantly lower than that in normal subjects.
These findings demonstrate that CO₂ reactivity measured by TCD evaluates the insufficiency of cerebral circulation in vertigo patients.