%0 Journal Article %A H. Yamauchi %A T. Higashi %A S. Kagawa %A Y. Kishibe %A M. Takahashi %T Chronic Hemodynamic Compromise and Cerebral Ischemic Events in Asymptomatic or Remote Symptomatic Large-Artery Intracranial Occlusive Disease %D 2013 %R 10.3174/ajnr.A3491 %J American Journal of Neuroradiology %X BACKGROUND AND PURPOSE: In asymptomatic or remote symptomatic LAICOD, the risk of ischemic events is low in general, but there may be a subgroup of higher risk patients who require aggressive medical management. The purpose of this study was to determine whether chronic hemodynamic compromise is a predictor of ischemic events in asymptomatic or remote symptomatic LAICOD. MATERIALS AND METHODS: We prospectively studied 51 asymptomatic, 19 coexistent asymptomatic, and 19 remote (>6 months) symptomatic patients with atherosclerotic intracranial internal carotid artery or middle cerebral artery disease by using 15O-PET. MP was defined as decreased CBF, increased OEF, and a decreased CBF/CBV ratio. All patients were followed up for 2 years or until occurrence of stroke or TIA or death. RESULTS: Bypass surgery was performed in 4 patients (2 with MP). Three cerebral ischemic events (1 TIA in an asymptomatic patient, 1 stroke, and 1 TIA in a remote symptomatic patient) occurred in the vascular territory ipsilateral to LAICOD. Kaplan-Meier analysis with censoring at the time of bypass surgery revealed that the incidence of ipsilateral ischemic events in patients with MP (2/5) was significantly higher than that in patients without MP (1/84) (log-rank test; P < .0001). The relative risk conferred by MP was 83.1 (95% confidence interval, 6.8–1017.4; P < .001). The incidence of ipsilateral ischemic events in patients with decreased CBF/CBV (2/9) was also significantly higher than that of patients without it (1/80) (P = .0001). CONCLUSIONS: Chronic hemodynamic compromise may be a predictor of ischemic events in both asymptomatic and remote symptomatic LAICOD. Abbreviations CIconfidence intervalCMRO2cerebral metabolic rate of oxygenLAICODlarge-artery intracranial occlusive diseaseMPmisery perfusionOEFoxygen extraction fraction %U https://www.ajnr.org/content/ajnr/early/2013/03/07/ajnr.A3491.full.pdf