title: The combination of baseline magnetic resonance perfusion-weighted imaging-derived tissue volume with severely prolonged arterial-tissue delay and diffusion-weighted imaging lesion volume is predictive of MCA-M1 recanalization in patients treated with endovascular thrombectomy.
abstract: BACKGROUND
  Indices of collateral flow deficit derived from MR perfusion imaging that are predictive of MCA-M1 recanalization after intravenous thrombolysis have been recently reported. Our objective was to test the performance of such MRI-derived collateral flow indices for prediction of recanalization after endovascular thrombectomy.
  
  
  METHODS
  Fifty-seven patients with MCA-M1 occlusion evaluated with multimodal MRI prior to thrombectomy were included. Bayesian processing allowed quantification of collateral perfusion indices like the volume of tissue with severely prolonged arterial-tissue delay (>6 s) (VolATD6). Baseline DWI lesion volume was also measured. Correlations with angiographic collateral flow grading and post-thrombectomy recanalization were assessed.
  
  
  RESULTS
  VolATD6 < 27 ml or DWI lesion volume <15 ml provide the most accurate diagnosis of excellent collateral supply (p < 0.0001). The combination of VolATD6 > 27 ml and DWI lesion volume >15 ml significantly discriminates recanalizers versus nonrecanalizers (whole cohort, p = 0.032; MERCI cohort (n = 50), p = 0.024). When both criteria are positive, 76.2 % of the patients treated with the MERCI retriever do not fully recanalize (p = 0.024). In multivariate analysis, the aforementioned combined criterion and the angiographic collateral grade are the only independent predictors of recanalization with the MERCI retriever (p = 0.015 and 0.029, respectively).
  
  
  CONCLUSIONS
  Bayesian arterial-tissue delay maps and DWI maps provide a non-invasive assessment of the degree of collateral flow and a combined index that is predictive of MCA-M1 recanalization after endovascular thrombectomy. Further studies are needed to evaluate the accuracy of this index in patients treated with novel stent retriever devices.
authors: Medical and Research & Innovation Departments, Olea Medical, 93 avenue des sorbiers, ZI Athelia IV, 13800, La Ciotat, France, francois.nicoli@olea-medical.com.
authors: F
authors: F
authors: Nicoli
authors: F
authors: F
authors: Scalzo
authors: J L
authors: JL
authors: Saver
authors: F
authors: F
authors: Pautot
authors: A
authors: A
authors: Mitulescu
authors: Y
authors: Y
authors: Chaibi
authors: N
authors: N
authors: Girard
authors: N
authors: N
authors: Salamon
authors: D S
authors: DS
authors: Liebeskind
mesh_terms: D000368:Aged; D002548:Cerebral Revascularization / Q000379:methods*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D020244:Infarction, Middle Cerebral Artery / Q000175:diagnosis* / Q000601:surgery*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D064847:Multimodal Imaging / Q000379:methods; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017131:Thrombectomy / Q000379:methods*; D016896:Treatment Outcome