title: Successful recanalization in acute basilar artery occlusion treated with endovascular therapy is independent of thrombus length.
abstract: OBJECTIVE
  As previously demonstrated, the recanalization rate and clinical outcome in patients with anterior circulation stroke treated with IV thrombolysis (IVT) depend on clot characteristics such as thrombus length and thrombus density. In patients with basilar artery occlusion (BAO) treated with IVT, the recanalization rate has also been shown to depend on thrombus length, although no cut-off value beyond which recanalization would seem impossible has been determined. We aim to evaluate the correlation of clot characteristics with recanalization rate and outcome in patients with BAO treated with endovascular therapy (EVT).
  
  
  METHODS
  We retrospectively assessed 51 consecutive patients with BAO treated with EVT. Thrombus length and thrombus density (in Hounsfield units, HU) were measured on thin slice non-enhanced cranial CT scan before treatment. Thrombolysis In Myocardial Infarction grade 2-3 was considered successful recanalization and 3-month modified Rankin Scale score 0-2 was considered a favorable outcome. To evaluate the correlation of clot characteristics with recanalization rate and outcome, a binary logistic regression test was computed.
  
  
  RESULTS
  Neither thrombus length nor thrombus density correlated with recanalization rate (OR 1.02, 95% CI 0.94 to 1.11, p=0.58 and OR 1.09, 95% CI 0.97 to 1.23, p=0.13, respectively). Thrombus density and thrombus length were not significantly different in patients with (n=41, 80.4%) or without (n=10, 19.6%) successful recanalization (52.3 HU vs 48.4 HU, p=0.07 and 8.2 mm vs 7.5 mm, p=0.91). However, higher clot density was correlated with a favorable outcome (OR 1.31, 95% CI 1.08 to 1.59, p=0.006) whereas thrombus length was not correlated with clinical outcome (OR 0.94, 95% CI 0.86 to 1.03, p=0.20).
  
  
  CONCLUSIONS
  Successful recanalization does not depend on thrombus length in patients with BAO treated with EVT. Recanalization can therefore be achieved despite high clot burden. Additionally, a high density of thrombi was a strong predictor of a favorable outcome.
authors: Department of Radiology and Neuroradiology, University Hospital of Schleswig-Holstein, Kiel, Germany.|Department of Neurology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors: Liang
authors: L
authors: Shu
authors: Department of Radiology and Neuroradiology, University Hospital of Schleswig-Holstein, Kiel, Germany.
authors: Christian
authors: C
authors: Riedel
authors: Department of Neurology, University Hospital of Schleswig-Holstein, Kiel, Germany.
authors: Johannes
authors: J
authors: Meyne
authors: Department of Radiology and Neuroradiology, University Hospital of Schleswig-Holstein, Kiel, Germany.
authors: Olav
authors: O
authors: Jansen
authors: Department of Radiology and Neuroradiology, University Hospital of Schleswig-Holstein, Kiel, Germany.
authors: Ulf
authors: U
authors: Jensen-Kondering
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001157:Arterial Occlusive Diseases / Q000000981:diagnostic imaging / Q000601:surgery*; D001488:Basilar Artery / Q000000981:diagnostic imaging / Q000601:surgery*; D015331:Cohort Studies; D057510:Endovascular Procedures / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D015912:Thrombolytic Therapy / Q000379:methods; D013927:Thrombosis / Q000000981:diagnostic imaging / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: CT; Stroke; Thrombolysis