Cerebrovascular reserve is commonly evaluated by measuring transcranial Doppler velocities after administration of the vasodilator acetazolamide. To assess the possibility that this test might confuse the interpretation of velocities obtained during routine carotid duplex studies, we measured transcranial and carotid velocities at multiple sites in four normal subjects at baseline and 10 and 30 min after injection of acetazolamide. Velocity elevation was significant in most sites of the extracranial internal carotid artery, absent in the external carotid artery, and of greater magnitude intracranially. The velocity elevation seen in the common and internal carotid arteries ranged between -2 and 36% and was significant (p < 0.05) at 11 of the 15 sites at 10 min and 7 of the sites at 30 min. Eight of the sites showed elevation greater than 20% at 10 min and four showed similar elevations at 30 min. There was an increase in diameter of the internal carotid artery approaching significance, explaining the lessened extracranial response. The magnitude of carotid velocity elevation due to acetazolamide administration can be high enough to produce overestimates of stenosis severity when velocity criteria are used. Institutions offering these tests should recognize this difficulty when scheduling diagnostic evaluations that include administration of acetazolamide.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of Vascular Technology|
|State||Published - Jan 1 1996|
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging
- Cardiology and Cardiovascular Medicine