title: Diagnostic accuracy of whole-brain CT perfusion in the detection of acute infratentorial infarctions.
abstract: BACKGROUND
  Although the diagnostic performance of whole-brain computed tomographic perfusion (WB-CTP) in the detection of supratentorial infarctions is well established, its value in the detection of infratentorial strokes remains less well defined. We examined its diagnostic accuracy in the detection of infratentorial infarctions and compared it to nonenhanced computed tomography (NECT), aiming to identify factors influencing its detection rate.
  
  
  METHODS
  Out of a cohort of 1380 patients who underwent WB-CTP due to suspected stroke, we retrospectively included all patients with MRI-confirmed infratentorial strokes and compared it to control patients without infratentorial strokes. Two blinded readers evaluated NECT and four different CTP maps independently for the presence and location of infratentorial ischemic perfusion deficits.
  
  
  RESULTS
  The study was designed as a retrospective case-control study and included 280 patients (cases/controls = 1/3). WB-CTP revealed a greater diagnostic sensitivity than NECT (41.4 vs. 17.1 %, P = 0.003). The specificity, however, was comparable (93.3 vs. 95.0 %). Mean transit time (MTT) and time to drain (TTD) were the most sensitive (41.4 and 40.0 %) and cerebral blood volume (CBV) the most specific (99.5 %) perfusion maps. Infarctions detected using WB-CTP were significantly larger than those not detected (15.0 vs. 2.2 ml; P = 0.0007); infarct location, however, did not influence the detection rate.
  
  
  CONCLUSIONS
  The detection of infratentorial infarctions can be improved by assessing WB-CTP as part of the multimodal stroke workup. However, it remains a diagnostic challenge, especially small volume infarctions in the brainstem are likely to be missed.
authors.affiliation: Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital of Munich, Munich, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Bollwein
authors.affiliation: Department of Neurology, Ludwig-Maximilians-University Hospital of Munich, Grosshadern Campus, Marchioninistr. 15, 81377, Munich, Germany.
authors.forename: Annika
authors.initials: A
authors.lastname: Plate
authors.affiliation: Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital of Munich, Munich, Germany.
authors.forename: Wieland H
authors.initials: WH
authors.lastname: Sommer
authors.affiliation: Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital of Munich, Munich, Germany.
authors.forename: Kolja M
authors.initials: KM
authors.lastname: Thierfelder
authors.affiliation: Department of Neuroradiology, South Nuremberg Hospital, Nuremberg, Germany.
authors.forename: Hendrik
authors.initials: H
authors.lastname: Janssen
authors.affiliation: Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital of Munich, Munich, Germany.
authors.forename: Maximilian F
authors.initials: MF
authors.lastname: Reiser
authors.affiliation: Department of Neurology, Ludwig-Maximilians-University Hospital of Munich, Grosshadern Campus, Marchioninistr. 15, 81377, Munich, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Straube
authors.affiliation: Department of Neurology, Ludwig-Maximilians-University Hospital of Munich, Grosshadern Campus, Marchioninistr. 15, 81377, Munich, Germany. Louisa.vonBaumgarten@med.uni-muenchen.de.
authors.forename: Louisa
authors.initials: L
authors.lastname: von Baumgarten
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D002531:Cerebellum / Q000000981:diagnostic imaging* / Q000473:pathology*; D002533:Cerebral Angiography / Q000379:methods*; D002544:Cerebral Infarction / Q000000981:diagnostic imaging* / Q000473:pathology*; D000072226:Computed Tomography Angiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
keywords: Infratentorial infarction; Ischemic stroke; Whole-brain CT perfusion imaging