Acetazolamide-Challenged Brain CT Perfusion before and after Carotid Stenting. |
Ho Sung Kim, Eun Jin Kim, Sun Yong Kim |
Department of Diagnostic Radiology, Ajou University, School of Medicine, Korea. J978005@lycos.co.kr |
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Abstract |
PURPOSE To test hypothesis that pre-stenting measurement of reactivity index by using acetazolamide-challenged CT perfusion could identify patients at risk for hyperperfusion after carotid stenting. MATERIALS AND METHODS For 24 regions of interest in 12 patients with symptomatic unilateral high-grade carotid stenosis, asymmetric indexes for cerebral blood volume, cerebral blood flow, and mean transit time and reactivity index were calculated from resting and acetazolamide-challenged CT perfusion before and 1 day after carotid stenting. We subsequently compared pre-stenting asymmetric indexes and reactivity index with percent increase of cerebral blood flow 1 day after carotid stenting. RESULTS Percent increase of cerebral blood flow on the first post-stenting day was not significantly different between visually decreased and normal cerebrovascular reserve groups. There was no significant correlation between pre-stenting asymmetric indexs of resting CT perfusion parameters and percent increase of cerebral blood flow 1 day after carotid stenting. On the other hand, pre-stenting reduction of reactivity index showed fair correlation with 1 day cerebral blood flow increase. However, hyperperfusion or hyperperfusion syndrome was not observed in any patient with reduced reactivity index. CONCLUSION Pre-stenting measurements of resting CT perfusion parameters and reactivity index could not predict hyperperfusion after carotid stenting. However, pre-stenting reduction of reactivity index seems to fairly correlate with immediate post-stenting cerebral blood flow increase.
Further studies with larger population should be performed to validate this preliminary result. |
Key Words:
Hyperperfusion; Hyperperfusion syndrome; CT perfusion; Carotid artery stenosis; Stent |
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