title: Whole brain CT perfusion in acute anterior circulation ischemia: coverage size matters.
abstract: BACKGROUND
  Our aim was to compare infarct core volume on whole brain CT perfusion (CTP) with several limited coverage sizes (i.e., 3, 4, 6, and 8 cm), as currently used in routine clinical practice.
  
  
  METHODS
  In total, 40 acute ischemic stroke patients with non-contrast CT (NCCT) and CTP imaging of anterior circulation ischemia were included. Imaging was performed using a 320-multislice CT. Average volumes of infarct core of all simulated partial coverage sizes were calculated. Infarct core volume of each partial brain coverage was compared with infarct core volume of whole brain coverage and expressed using a percentage. To determine the optimal starting position for each simulated CTP coverage, the percentage of infarct coverage was calculated for every possible starting position of the simulated partial coverage in relation to Alberta Stroke Program Early CT Score in Acute Stroke Triage (ASPECTS 1) level.
  
  
  RESULTS
  Whole brain CTP coverage further increased the percentage of infarct core volume depicted by 10% as compared to the 8-cm coverage when the bottom slice was positioned at the ASPECTS 1 level. Optimization of the position of the region of interest (ROI) in 3 cm, 4 cm, and 8 cm improved the percentage of infarct depicted by 4% for the 8-cm, 7% for the 4-cm, and 13% for the 3-cm coverage size.
  
  
  CONCLUSIONS
  This study shows that whole brain CTP is the optimal coverage for CTP with a substantial improvement in accuracy in quantifying infarct core size. In addition, our results suggest that the optimal position of the ROI in limited coverage depends on the size of the coverage.
authors.affiliation: Department of Radiology, Erasmus Medical Centre, Postbus 2040, 3000 CA, Rotterdam, The Netherlands, b.emmer@erasmusmc.nl.
authors.forename: B J
authors.initials: BJ
authors.lastname: Emmer
authors.forename: M
authors.initials: M
authors.lastname: Rijkee
authors.forename: J M
authors.initials: JM
authors.lastname: Niesten
authors.forename: M J H
authors.initials: MJ
authors.lastname: Wermer
authors.forename: B K
authors.initials: BK
authors.lastname: Velthuis
authors.forename: M A A
authors.initials: MA
authors.lastname: van Walderveen
mesh_terms: D000208:Acute Disease; D000368:Aged; D002545:Brain Ischemia / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D008297:Male; D020521:Stroke / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed