title: Comparison of different population-averaged arterial-input-functions in dynamic contrast-enhanced MRI of the prostate: Effects on pharmacokinetic parameters and their diagnostic performance.
abstract: OBJECTIVE
  To assess the effect of different population-averaged arterial-input-functions (pAIF) on pharmacokinetic parameters from dynamic contrast-enhanced MRI (DCE-MRI) and their diagnostic accuracy regarding the detection of potentially malignant prostate lesions.
  
  
  METHODS
  66 male patients (age 65.4±10.8y) with suspected prostate cancer underwent multiparametric MRI of the prostate including T2-w, DWI-w and DCE-MRI sequences at a 3T MRI scanner. All detected lesions were categorized based on ACR PI-RADS version 2 and divided into 2 groups (A: PI-RADS ≤3, n=32; B: PI-RADS >3, n=34). In each DCE-MRI dataset, pharmacokinetic parameters (Ktrans, Kep and ve) and goodness of fit (chi(2)) were generated using the Tofts model with 3 different pAIFs (fast, intermediate, slow) as provided by a commercially available postprocessing software. Pharmacokinetic parameters, their diagnostic accuracies and model fits were compared for the 3 pAIFs.
  
  
  RESULTS
  Ktrans, Kep and ve differed significantly among the 3 pAIFs (all p<.001). Ktrans and Kep were significantly higher in group B compared to group A (all p<.001). For chi(2), lowest results (representing highest goodness of fit) were found for intermediate pAIF (chi(2) 0.073). ROC analyses revealed comparable diagnostic accuracies for the different pAIFs, which were high for Ktrans and Kep and low for ve.
  
  
  CONCLUSIONS
  Choosing various pAIF types causes a high variability in pharmacokinetic parameter estimates. Therefore, it is of great importance to consider this as potential artifact and thus keep AIF type selection constant in DCE-MRI studies.
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany. Electronic address: ahmed.e.othman@googlemail.com.
authors.forename: Ahmed E
authors.initials: AE
authors.lastname: Othman
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Falkner
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors.forename: David-Emanuel
authors.initials: DE
authors.lastname: Kessler
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors.forename: Petros
authors.initials: P
authors.lastname: Martirosian
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors.forename: Jakob
authors.initials: J
authors.lastname: Weiss
authors.affiliation: Department of Urology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076, Tuebingen, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Kruck
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Kaufmann
authors.affiliation: Siemens Healthcare GmbH, Erlangen, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Grimm
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Kramer
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Nikolaou
authors.affiliation: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors.forename: Mike
authors.initials: M
authors.lastname: Notohamiprodjo
mesh_terms: D000368:Aged; D016477:Artifacts; D003287:Contrast Media / Q000493:pharmacokinetics*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D011467:Prostate / Q000000981:diagnostic imaging*; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D012984:Software
chemical_list: D003287:Contrast Media
keywords: Arterial-input-function; DCE-MRI; Dynamic imaging; Magnetic resonance imaging; Prostate; Prostate cancer