Prediction of Futile Recanalization Following Mechanical Thrombectomy for Acute Ischemic Stroke Using Quantitative Electroencephalography: Temporal Delta/Alpha Power Ratio as an Independent Predictor
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Acute ischemic stroke
Quantitative electroencephalography
Delta/alpha power ratio
Mechanical thrombectomy
Futile recanalization



Submitted : 2024-04-23
Accepted : 2024-05-08
Published : 2024-05-23


Objective: Previous studies have reported associations between quantitative electroencephalography (QEEG) parameters and acute ischemic stroke (AIS). However, the relationship between QEEG parameters and clinical outcomes in AIS patients with complete intracranial recanalization post-thrombectomy has been rarely explored. This study aims to evaluate the relationship between the QEEG parameter, specifically the regional delta/alpha power ratio (DAR), and futile recanalization (FR) in AIS patients with anterior circulation large vessel occlusion undergoing mechanical thrombectomy. Methods: A retrospective study was conducted on AIS patients with anterior circulation large artery occlusion who underwent mechanical thrombectomy and achieved complete vessel recanalization (mTICI 2b or 3) between May 2020 and October 2021. Patients with complete recanalization were categorized into effective recanalization and FR groups based on their modified Rankin scale (mRS) scores at three months. The FR group was defined as having an mRS score of 3–6 at three months, while the effective recanalization group had an mRS score of 0–2. Univariate analysis was performed to identify factors associated with FR, and factors with P < 0.05 were further analyzed using binary logistic regression to determine independent predictors of FR. Receiver operating characteristic (ROC) curve analysis was employed to assess the predictive ability of identified factors for FR. Results: Among 152 patients, 81 had effective recanalization, while 71 had FR, resulting in an FR rate of 46.7%. Univariate analysis revealed that baseline characteristics such as admission NIH stroke scale (NIHSS) score, neutrophil ratio, hemorrhagic transformation rate, number of thrombectomy passes, and time to recanalization were higher, whereas ASPECTS score was lower in the FR group compared to the effective recanalization group, all with statistical significance (P < 0.05). Electrophysiologically, DAR values in the affected frontal and temporal regions were significantly higher in the FR group compared to the effective recanalization group (P < 0.05). After adjusting for potential confounders, multivariable adjusted regression analysis demonstrated that regional DAR (odds ratio [OR] 1.205 [95% CI 1.041–1.396], P = 0.013), neutrophil ratio (OR 1.040 [95% CI 1.040–1.081], P = 0.042), ASPECTS score (OR 0.556 [95% CI 0.397–0.780], P = 0.001), and admission NIHSS score (OR 1.209 [95% CI 1.064–1.373], P = 0.004) were independent predictors of FR. ROC analysis indicated that combining regional DAR, especially temporal DAR, with other clinical factors could effectively predict adverse outcomes. Conclusion: Baseline characteristics including NIHSS score, ASPECTS score, and neutrophil ratio are independent predictors of FR, while electrophysiological characteristics, particularly temporal DAR of regional DAR, are closely associated with adverse outcomes at three months post-mechanical thrombectomy in AIS patients with anterior circulation large vessel occlusion. This shows that models incorporating temporal DAR can effectively predict FR.


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