Comparison of Superior and Inferior Division Occlusions Treated with Endovascular Thrombectomy.

BACKGROUND AND PURPOSE: Several studies have shown that thrombectomy is safe and effective in occlusions of the M2 segment of the middle cerebral artery. This retrospective study compared superior and inferior division occlusions regarding radiological and clinical outcomes.

METHODS: Between 2009 and 2017, patients treated with thrombectomy due to occlusion of the superior or inferior division were selected. Univariate and multivariate analyses were performed to identify predictors of outcome and compare superior and inferior division occlusions.

RESULTS: A total of 140 patients with superior (n = 87) and inferior (n = 53) division occlusion were included. Of patients with inferior division occlusion 66.0% achieved good outcome compared to 48.3% in patients with superior division occlusion (P = 0.041). Time from groin puncture to reperfusion, recanalization success, complication rate, hemorrhage rate and follow-up infarct size were similar in both groups. Independent predictors of good outcome were baseline Alberta Stroke Program Early CT Score (ASPECTS) (odds ratio, OR 1.74, 95% confidence interval, CI 1.21-2.58, P = 0.004), time from groin puncture to reperfusion (OR 0.99, 95% CI 0.98-1.0, P = 0.019) and Thrombolysis In Cerebral Infarction (TICI) score 2b-3 (OR 4.51, 95% CI 1.31-18.74, P = 0.024). Superior division occlusion was an independent predictor of poor outcome (OR 2.41, 95% CI 1.05-5.80, P = 0.042). Dominance of the occluded vessel and side of occlusion were not predictive.

CONCLUSION: Patients with superior division occlusion appear to have a lower chance of achieving good outcome despite similar recanalization rates and complication rates compared to inferior division occlusions.