title: Subtracted Dynamic MR Perfusion Source Images (sMRP-SI) provide Collateral Blood Flow Assessment in MCA Occlusions and Predict Tissue Fate.
abstract: OBJECTIVE
  Collateral blood flow is accepted as a predictive factor of tissue fate in ischemic stroke. Thus, we aimed to evaluate a new method derived from MR perfusion source images to assess collateral flow in patients with ICA/MCA occlusions.
  
  
  METHODS
  A total of 132 patients of the prospective 1000+ study were examined. MR perfusion source images were assessed according to Δimg_n = img_n + 1 - img_n - 1 using the five-grade Higashida collateral flow rating system. Higashida scores were correlated to mismatch (MM) volume, mismatch ratio, day 6 FLAIR lesion volumes and day 90 mRS.
  
  
  RESULTS
  Patients with Higashida scores 3 and 4 had significantly lower admission NIHSS, smaller FLAIR day 6 lesion volumes (p < 0.001) and higher rates of better long-term outcome (mRS 0-2, p = 0.002). There was a linear trend for the association of Higashida grade 1 (p = 0.002) and 2 (p = 0.001) with unfavourable outcome (day 90 mRS 3-6), but no significant association was found for MM volume, MM ratio and day 90 mRS. Inter-rater agreement was 0.58 (95% CI 0.43-0.73) on day 1, 0.70 (95% CI 0.58-0.81) on day 2.
  
  
  CONCLUSIONS
  sMRP-SI Higashida score offers a non-invasive collateral vessel and tissue perfusion assessment of ischemic tissue. The predictive value of Higashida rating proved superior to MM with regard to day 90 mRS.
  
  
  CONCLUSIONS
  • Assessment of collateral flow using subtracted dynamic MR perfusion source imaging (sMRP-SI). • sMRP-SI offers additional information about morphological characteristics of ischemic brain tissue. • sMRP-SI collateral flow assessment proves superior to mismatch volume. • Better collateral flow was significantly associated with better outcome (day 90 mRS).
authors.affiliation: Academic Neuroradiology, Center for Stroke Research (CSB), Charité-Universitätsmedizin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200, Berlin, Germany. kersten.villringer@charite.de.
authors.forename: Kersten
authors.initials: K
authors.lastname: Villringer
authors.affiliation: Academic Neuroradiology, Center for Stroke Research (CSB), Charité-Universitätsmedizin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200, Berlin, Germany.
authors.forename: Rafael
authors.initials: R
authors.lastname: Serrano-Sandoval
authors.affiliation: Center for Stroke Research, Charité, Universitätsmedizin Berlin, Berlin, Germany.|Department for Biostatistics and Clinical Epidemiology, Charité, Berlin, Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Grittner
authors.affiliation: Academic Neuroradiology, Center for Stroke Research (CSB), Charité-Universitätsmedizin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200, Berlin, Germany.
authors.forename: Ivana
authors.initials: I
authors.lastname: Galinovic
authors.affiliation: Center for Stroke Research, Charité, Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Alice
authors.initials: A
authors.lastname: Schneider
authors.affiliation: Academic Neuroradiology, Center for Stroke Research (CSB), Charité-Universitätsmedizin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200, Berlin, Germany.
authors.forename: Ann-Christin
authors.initials: AC
authors.lastname: Ostwaldt
authors.affiliation: Academic Neuroradiology, Center for Stroke Research (CSB), Charité-Universitätsmedizin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200, Berlin, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Brunecker
authors.affiliation: Department of Neurology and Center for Stroke Research, Charité, Berlin, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Rocco
authors.affiliation: Academic Neuroradiology, Center for Stroke Research (CSB), Charité-Universitätsmedizin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200, Berlin, Germany.
authors.forename: Jochen B
authors.initials: JB
authors.lastname: Fiebach
mesh_terms: D000368:Aged; D001921:Brain / Q000098:blood supply / Q000473:pathology; D002545:Brain Ischemia / Q000473:pathology*; D003097:Collateral Circulation / Q000502:physiology*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D020768:Middle Cerebral Artery / Q000473:pathology*; D011446:Prospective Studies; D020521:Stroke / Q000473:pathology*
keywords: Collateral circulation; MRI; Outcome assessment; Perfusion; Stroke