Letter by Bennis et al Regarding Article, “Cerebral Near-Infrared Spectroscopy: A Potential Approach for Thrombectomy Monitoring”

With interest, we read the brief report by Ritzenthaler et al1 concerning cerebral near-infrared spectroscopy during thrombectomy in 17 patients with acute anterior circulation ischemic stroke. The study states that before thrombectomy, frontal regional oxygen brain saturation (rSO2) significantly correlates with magnetic resonance imaging perfusion parameters. Based on Figure II in the online-only Data Supplement in the study by Ritzenthaler et al, we respectfully disagree with this conclusion. The mentioned figure shows that the correlations between rSO2 and Time-To-Maximum (TMax) or mean transit time are weak and mainly driven by a large outlier. If this outlier is excluded, correlations are likely to be nonsignificant. In addition, rSO2 shows large variation with equal ranges for both …