title: Thrombus attenuation does not predict angiographic results of mechanical thrombectomy with stent retrievers.
abstract: OBJECTIVE
  Mechanical thrombectomy with stent retrievers in acute stroke has emerged as a promising new technique, with the highest recanalization rate of the therapeutic procedures available thus far. However, in up to 20% of the cases, mechanical thrombectomy with stent retrievers results in poor angiographic outcomes, with Thrombolysis in Cerebral Infarction scores ≤2a. The purpose of this study was to investigate whether thrombus attenuation on the initial CT scan can predict the angiographic outcome of the recanalization procedure in MCA occlusions.
  
  
  METHODS
  The data of 70 patients with acute MCA occlusions who underwent endovascular treatment with stent retrievers in our department were included. We analyzed thrombus attenuations, angiographic outcome, and periprocedural thrombus fragmentation.
  
  
  RESULTS
  The mean thrombus attenuation was 49.8 ± 7.8 HU and the mean difference from the attenuation of the contralateral MCA was 9.9 ± 8.0 HU. There were no significant differences in the thrombus attenuations of occlusions that were successfully recanalized (modified Thrombolysis in Cerebral Infarction ≥2b) and those that were not. Neither were there significant correlations of thrombus attenuations and periprocedural thrombus fragmentations that occurred in 64.3%. We found a nonsignificantly higher rate of recanalizations with modified Thrombolysis in Cerebral Infarction ≥2b when the difference from the attenuation of the contralateral MCA was between 1-20 HU.
  
  
  CONCLUSIONS
  In contrast to results of other revascularization procedures as published in a recent study, the angiographic result of mechanical thrombectomy with stent retrievers is not predicted by thrombus attenuation.
authors.affiliation: Department of Neuroradiology, Saarland University Hospital, Homburg, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Yilmaz
authors.forename: C
authors.initials: C
authors.lastname: Roth
authors.forename: W
authors.initials: W
authors.lastname: Reith
authors.forename: P
authors.initials: P
authors.lastname: Papanagiotou
mesh_terms: D000368:Aged; D001807:Blood Vessel Prosthesis; D002533:Cerebral Angiography / Q000379:methods*; D020878:Device Removal / Q000295:instrumentation*; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000601:surgery*; D020767:Intracranial Thrombosis; D008297:Male; D061185:Mechanical Thrombolysis / Q000295:instrumentation*; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D015607:Stents; D016896:Treatment Outcome