Cerebral Blood Flow Alteration by Acetazolamide During Carotid Balloon Occlusion

Background and Purpose We attempted to clarify the role of the acetazolamide-reactive mechanism in cerebral hemodynamic autoregulation and to establish a useful method of estimation using the acetazolamide test. Methods We examined 18 patients whose cerebral hemodynamics were considered to be normal and whose cerebral blood flow (CBF) was maintained during the balloon occlusion test (BOT) of the internal carotid artery. We measured the mean stump pressure (MSTP) and the mean CBF in the middle cerebral arterial territory using a xenon-enhanced CT system during BOT with and without acetazolamide activation. We obtained the asymmetry ratio (AR=occluded CBF/contralateral CBF) and the increased CBF parameters caused by acetazolamide activation expressed as an absolute value (ΔCBF) and a percentage (%ΔCBF) for the occluded side. Results AR during BOT with and without acetazolamide activation differed significantly (P<.001, paired t test) despite the lack of significant MSTP changes. Furthermore, although there ...