Association of NIRS changes during and after mechanical thrombectomy with early clinical and radiological outcomes

Introduction: This study aimed to evaluate the changes in cerebral NIRS parameters before and after recanalization during thrombectomy and to investigate their relationship with early radiological and clinical outcomes.Methods: Patients who underwent mechanical thrombectomy for acute ischemic stroke and were monitored with NIRS were evaluated. Oxyhemoglobin, deoxyhemoglobin, total hemoglobin, and THI values were recorded for 24 hours. The last measurement before recanalization and the first measurement after recanalization were compared, and Δ values (post–pre) were calculated. The association of NIRS changes with the ASPECT score on follow-up CT, the 24-hour NIHSS, and the relationship between baseline and 24-hour NIHSS scores was assessed with Spearman correlation analysis. Pre–post changes were compared with the Wilcoxon test.Results: Ten patients in whom the time of recanalization could be determined were analyzed. A moderate-to-strong negative correlation was found between ΔTHI and the follow-up CT ASPECT score (ρ=−0.640; p=0.046). Δoxyhemoglobin showed a similar relationship with ASPECT (ρ=−0.630; p=0.051). A moderate-to-strong negative correlation was also observed between total hemoglobin and ASPECT (ρ=−0.612; p=0.060). A moderate-to-strong negative relationship was observed between Δoxyhemoglobin and NIHSS improvement (ρ=−0.567; p=0.087). None of the pre–post NIRS changes was statistically significant by the Wilcoxon test (all p>0.05) (Figures 1 and 2).Discussion/Conclusion: This pilot study provides preliminary evidence that recanalization-related changes in NIRS parameters during thrombectomy may be associated with early radiological outcomes. In particular, moderate-to-strong associations were observed between ΔTHI, Δoxyhemoglobin, and Δtotal hemoglobin and the follow-up CT ASPECT score. Because of the small sample size, the findings should be regarded as exploratory. These associations need to be confirmed in larger patient series.Keywords: