title: Clinical Outcome Predicted by Collaterals Depends on Technical Success of Mechanical Thrombectomy in Middle Cerebral Artery Occlusion.
abstract: BACKGROUND
  This study aimed to analyze the effects of technical outcome of mechanical thrombectomy (MTE) on the associations between collateral status, assessed with pretreatment computed tomography angiography (CTA), and neurological and functional outcome, as well as associations between collaterals and metabolic risk factors (arterial hypertension, diabetes, hyperlipidemia, overweight).
  
  
  METHODS
  Prospectively collected data of 115 patients with CTA-proven isolated middle cerebral artery occlusion treated successfully with MTE (Thrombosis in Cerebral Infarction [TICI] scale 2b or 3) were assessed retrospectively. Initial CTAs were assessed for the regional leptomeningeal collateralization score (rLMC), neurological status was determined with the National Institutes of Health Stroke Scale (NIHSS) at admission and discharge, and mid-term functional outcome was assessed using the modified Rankin scale (mRS) 90 days after MTE.
  
  
  RESULTS
  NIHSS score at admission was significantly associated with rLMC (P = .004), whereas rLMC and NIHSS at discharge showed no significant associations (P = .12). Better rLMC was significantly associated with improved mid-term mRS (P = .018). This association was even more significant after complete MTE (TICI 3; P = .011). Arterial hypertension was significantly more often found in patients with poor rLMC (0-10) than in patients with good rLMC (11-20; P = .046), yet other risk factors showed no significant associations (P > .05).
  
  
  CONCLUSIONS
  In patients with successful MTE, good collaterals were associated with better neurological status at admission and favorable mid-term functional outcome. In patients with complete MTE, associations were even more significant compared with those with "almost complete" MTE, suggesting a synergistic effect between good collaterals and complete MTE and a predictive value of collaterals for estimation of the potential clinical benefit of MTE.
authors.affiliation: Department of Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany; Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California. Electronic address: alexandra.gersing@tum.de.
authors.forename: Alexandra S
authors.initials: AS
authors.lastname: Gersing
authors.affiliation: Department of Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany; Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California.
authors.forename: Benedikt J
authors.initials: BJ
authors.lastname: Schwaiger
authors.affiliation: Department of Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Justus F
authors.initials: JF
authors.lastname: Kleine
authors.affiliation: Department of Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Kaesmacher
authors.affiliation: Department of Neurology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Silke
authors.initials: S
authors.lastname: Wunderlich
authors.affiliation: Department of Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Friedrich
authors.affiliation: Department of Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Prothmann
authors.affiliation: Department of Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Claus
authors.initials: C
authors.lastname: Zimmer
authors.affiliation: Department of Neuroradiology, Technische Universität München, Klinikum rechts der Isar, Munich, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Boeckh-Behrens
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015424:Reperfusion / Q000379:methods; D012189:Retrospective Studies; D012720:Severity of Illness Index; D017131:Thrombectomy / Q000379:methods*; D015898:Tomography Scanners, X-Ray Computed; D016896:Treatment Outcome
keywords: Stroke; collateralization; endovascular therapy; mechanical thrombectomy