Absent hyperdense middle cerebral artery sign is associated with poor functional outcome after mechanical thrombectomy

Background The hyperdense middle cerebral artery sign on computed tomography indicates proximal middle cerebral artery occlusion. Recent reports suggest an association between the hyperdense sign and successful reperfusion. The prognostic value of the hyperdense middle cerebral artery sign in patients receiving mechanical thrombectomy has not been extensively studied. Aims Our study aims to evaluate the association between the hyperdense middle cerebral artery sign and functional outcome in patients with M1 occlusions that had undergone mechanical thrombectomy. Methods We conducted a single-center retrospective observational cohort study of 102 consecutive patients presenting with acute M1 occlusions that had undergone mechanical thrombectomy. Patients were stratified into cohorts based on the presence of hyperdense middle cerebral artery sign visually assessed on computed tomography by two readers. The outcomes of interests were functional disability measured by the ordinal Modified Rankin Scale (mRS) at 90 days, mortality, reperfusion status and hemorrhagic conversion. Results Out of the 102 patients with M1 occlusions, 71 had hyperdense middle cerebral artery sign. There was no significant difference between the cohorts in age, baseline mRS, NIHSS, ASPECTS, and time to reperfusion. The absence of hyperdense middle cerebral artery sign was associated with increased odds of being dependent or dying (higher mRS) (OR: 3.24, 95% CI: 1.30–8.06, p = 0.011) after adjusting for other significant predictors, including age, female sex, hypertension, presenting serum glucose, ASPECTS, CTA collateral score, and successful reperfusion. Conclusion The absence of hyperdense middle cerebral artery sign is associated with worse functional outcome in patients presenting with M1 occlusions undergoing thrombectomy.