title: Prediction of outcome in patients with suspected acute ischaemic stroke with CT perfusion and CT angiography: the Dutch acute stroke trial (DUST) study protocol.
abstract: BACKGROUND
  Prediction of clinical outcome in the acute stage of ischaemic stroke can be difficult when based on patient characteristics, clinical findings and on non-contrast CT. CT perfusion and CT angiography may provide additional prognostic information and guide treatment in the early stage. We present the study protocol of the Dutch acute Stroke Trial (DUST). The DUST aims to assess the prognostic value of CT perfusion and CT angiography in predicting stroke outcome, in addition to patient characteristics and non-contrast CT. For this purpose, individualised prediction models for clinical outcome after stroke based on the best predictors from patient characteristics and CT imaging will be developed and validated.
  
  
  METHODS
  The DUST is a prospective multi-centre cohort study in 1500 patients with suspected acute ischaemic stroke. All patients undergo non-contrast CT, CT perfusion and CT angiography within 9 hours after onset of the neurological deficits, and, if possible, follow-up imaging after 3 days. The primary outcome is a dichotomised score on the modified Rankin Scale, assessed at 90 days. A score of 0-2 represents good outcome, and a score of 3-6 represents poor outcome. Three logistic regression models will be developed, including patient characteristics and non-contrast CT (model A), with addition of CT angiography (model B), and CT perfusion parameters (model C). Model derivation will be performed in 60% of the study population, and model validation in the remaining 40% of the patients. Additional prognostic value of the models will be determined with the area under the curve (AUC) from the receiver operating characteristic (ROC) curve, calibration plots, assessment of goodness-of-fit, and likelihood ratio tests.
  
  
  CONCLUSIONS
  This study will provide insight in the added prognostic value of CTP and CTA parameters in outcome prediction of acute stroke patients. The prediction models that will be developed in this study may help guide future treatment decisions in the acute stage of ischaemic stroke.
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100, HP E01,132, 3584 CX, Utrecht, The Netherlands. T.vanSeeters@umcutrecht.nl.
authors.forename: Tom
authors.initials: T
authors.lastname: van Seeters
authors.forename: Geert Jan
authors.initials: GJ
authors.lastname: Biessels
authors.forename: Irene C
authors.initials: IC
authors.lastname: van der Schaaf
authors.forename: Jan Willem
authors.initials: JW
authors.lastname: Dankbaar
authors.forename: Alexander D
authors.initials: AD
authors.lastname: Horsch
authors.forename: Merel J A
authors.initials: MJ
authors.lastname: Luitse
authors.forename: Joris M
authors.initials: JM
authors.lastname: Niesten
authors.forename: Willem P T M
authors.initials: WP
authors.lastname: Mali
authors.forename: L Jaap
authors.initials: LJ
authors.lastname: Kappelle
authors.forename: Yolanda
authors.initials: Y
authors.lastname: van der Graaf
authors.forename: Birgitta K
authors.initials: BK
authors.lastname: Velthuis
mesh_terms: D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology; D002533:Cerebral Angiography / Q000379:methods; D015331:Cohort Studies; D005500:Follow-Up Studies; D006801:Humans; D009426:Netherlands / Q000453:epidemiology; D010477:Perfusion / Q000379:methods; D011237:Predictive Value of Tests; D011446:Prospective Studies; D020521:Stroke / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome