Cerebral hyperperfusion syndrome (CHS) is a serious complication following carotid
artery stenting (CAS), but definitive early prediction of CHS has not been established.
Here, we evaluated whether indocyanine green kinetics and near-infrared spectroscopy
(ICG-NIRS) with hyperventilation (HV) and the breath-holding (BH) test can predict
hyperperfusion phenomenon after CAS. The blood flow index (BFI) ratio during HV and
BH was prospectively monitored using ICG-NIRS in 66 patients scheduled to undergo
CAS. Preoperative cerebrovascular reactivity (CVR) and the postoperative asymmetry
index (AI) were also assessed with single-photon emission computed tomography before
and after CAS and the correlation with the BFI HV/rest ratio, BFI BH/rest ratio was
evaluated. Twelve cases (18%) showed hyperperfusion phenomenon, and one (1.5%) showed
CHS after CAS. A significant linear correlation was observed between the BFI HV/rest
ratio, BFI BH/rest ratio, and preoperative CVR. A significant linear correlation was
observed between the BFI HV/rest ratio and postoperative AI (r = 0.674, P < 0.0001).
A BFI HV/rest ratio of 0.88 or more was the optimal cut-off point to predict hyperperfusion
phenomenon according to receiver operating characteristic curve analyses. HV and BH
test under ICG-NIRS is a useful tool for detection of hyperperfusion phenomenon in
patients who underwent CAS.