title: Diagnosis of acute ischemia using dual energy CT after mechanical thrombectomy.
abstract: OBJECTIVE
  To assess the performance of dual energy unenhanced CT in the detection of acute ischemia after mechanical thrombectomy.
  
  
  METHODS
  Retrospective study, approved by the local institutional review board, including all patients that underwent intra-arterial thrombectomy in our institution over a period of 2 years. The presence of acute ischemia and hemorrhage was evaluated by three readers. Sensitivity and specificity of the non-contrast CT weighted sum image (NCCT) and the virtual non-contrast reconstructed image (VNC) were estimated and compared using generalized estimating equations to account for the non-independence of regions in each patient.
  
  
  RESULTS
  58 patients (27 women and 31 men; mean age 70.4 years) were included in the study, yielding 580 regions of interest. Sensitivity and specificity in detecting acute ischemia were higher for all readers when using VNC, with a significant increase in sensitivity for two readers (p<0.001 and 0.01) and a significant increase in specificity in one reader (p<0.001). Specificity in detecting hemorrhage was excellent for all readers.
  
  
  CONCLUSIONS
  Dual energy unenhanced CT VNC images were superior in the identification of acute ischemia in comparison with NCCT.
authors.affiliation: Department of Radiology, Geneva University Hospitals, Geneva, Switzerland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Gariani
authors.affiliation: Department of Neuroradiology, Geneva University Hospitals, Geneva, Switzerland.
authors.forename: Victor
authors.initials: V
authors.lastname: Cuvinciuc
authors.affiliation: Department of Clinical Epidemiology, Department of Health and Community Medicine, Geneva University Hospitals, Geneva, Switzerland.
authors.forename: Delphine
authors.initials: D
authors.lastname: Courvoisier
authors.affiliation: Siemens AG, Healthcare Sector, Forchheim, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Krauss
authors.affiliation: Department of Neuroradiology, Geneva University Hospitals, Geneva, Switzerland.
authors.forename: Vitor
authors.initials: V
authors.lastname: Mendes Pereira
authors.affiliation: Department of Neurology, Geneva University Hospitals, Geneva, Switzerland.
authors.forename: Roman
authors.initials: R
authors.lastname: Sztajzel
authors.affiliation: Department of Neuroradiology, Geneva University Hospitals, Geneva, Switzerland.
authors.forename: Karl-Olof
authors.initials: KO
authors.lastname: Lovblad
authors.affiliation: Department of Neuroradiology, Geneva University Hospitals, Geneva, Switzerland.
authors.forename: Maria Isabel
authors.initials: MI
authors.lastname: Vargas
mesh_terms: D000208:Acute Disease; D000368:Aged; D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000628:therapy*; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography; D008297:Male; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D017131:Thrombectomy; D014057:Tomography, X-Ray Computed
keywords: CT; Hemorrhage; Stroke; Thrombectomy