Cerebral Near-Infrared Spectroscopy

Background and Purpose— Regional brain oxygen saturation (rSO2 ) changes, assessed by cerebral near-infrared spectroscopy, are likely influenced by cerebral hemodynamic fluctuations induced by thrombectomy of acute proximal occlusion. We studied the correlations between rSO2 and baseline magnetic resonance imaging perfusion parameters and the relationship between rSO2 changes, recanalization, and clinical outcome.Methods— Seventeen acute ischemic stroke patients, treated with mechanical thrombectomy, were monitored using bilateral near-infrared spectroscopy before, during, and continuously for 24 hours after the procedure. All patients had baseline brain magnetic resonance imaging with perfusion weighted imaging. Results— rSO2 was only correlated with baseline Tmax (ρ=−0.42;P <0.05) and mean transit time (ρ=−0.45;P <0.05) within forehead explored areas. Before thrombectomy, an interhemispheric rSO2 difference was noted, and this diminished over time when recanalization had occurred (median [interquartile range], −8 [−12 to −5] to 3 [−3 to 7];P =0.01). rSO2 changes were not correlated with clinical outcome.Conclusions— rSO2 was merely correlated with baseline Tmax and mean transit time magnetic resonance imaging perfusion parameters. Multiple sites recording beyond frontal pole explored areas may provide more relevant correlation with hemodynamic parameters.