title: Correlation of magnetic resonance signal characteristics and perfusion parameters assessed by volume perfusion computed tomography in hepatocellular carcinoma: Impact on lesion characterization.
abstract: OBJECTIVE
  To find out if magnetic resonance (MR)-signal characteristics of hepatocellular carcinomas (HCC) correlate with perfusion parameters assessed by volume perfusion computed tomography (VPCT).
  
  
  METHODS
  From October 2009 to January 2014, 26 (mean age, 69.3 years) patients with 36 HCC lesions who underwent both VPCT and MR liver imaging were analysed. We compared signal intensity in the T1w- and T2w-images and wash-in/wash-out kinetics on post-contrast MR images with mean values of blood flow (BF, mL/100 mL per minute), blood volume (BV, mL/100 mL), k-trans (mL/100 mL per minute), arterial liver perfusion (mL/100 mL per minute), portal venous perfusion and hepatic perfusion index (HPI, %) obtained by VPCT. Signal intensity on magnetic resonance imaging (MRI) was classified hyper/iso/hypointense compared with surrounding liver parenchyma.
  
  
  RESULTS
  Signal intensity on native T1w- and T2w-images was hyper/iso/hypo in 4/16/16 and 21/14/1 lesions, respectively. Wash-in and wash-out contrast kinetics were found on MRI in 33 of 36 lesions (91.7%) and 25 of 36 lesions (69.4%), respectively. The latter was observed significantly more often in higher graded lesions (P < 0.005). HPI was 94.7% ± 6.5%. There was no significant relationship between lesion's MR-signal intensity, MR signal combinations, size and any of the VPCT-perfusion parameters. However HPI was constantly high in all HCC lesions.
  
  
  CONCLUSIONS
  VPCT parameters add limited value to MR-lesion characterization. However in HCC lesions with atypical MR signal characteristics HPI can add a parameter to ensure HCC diagnosis.
authors.affiliation: Gerd Grözinger, Roland Syha, Dominik Ketelsen, Konstantin Nikolaou, Marius Horger, Department of Diagnostic and Interventional Radiology, Eberhard Karls University, 72076 Tübingen, Germany.
authors.forename: Gerd
authors.initials: G
authors.lastname: Grözinger
authors.affiliation: Gerd Grözinger, Roland Syha, Dominik Ketelsen, Konstantin Nikolaou, Marius Horger, Department of Diagnostic and Interventional Radiology, Eberhard Karls University, 72076 Tübingen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Bitzer
authors.affiliation: Gerd Grözinger, Roland Syha, Dominik Ketelsen, Konstantin Nikolaou, Marius Horger, Department of Diagnostic and Interventional Radiology, Eberhard Karls University, 72076 Tübingen, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Syha
authors.affiliation: Gerd Grözinger, Roland Syha, Dominik Ketelsen, Konstantin Nikolaou, Marius Horger, Department of Diagnostic and Interventional Radiology, Eberhard Karls University, 72076 Tübingen, Germany.
authors.forename: Dominik
authors.initials: D
authors.lastname: Ketelsen
authors.affiliation: Gerd Grözinger, Roland Syha, Dominik Ketelsen, Konstantin Nikolaou, Marius Horger, Department of Diagnostic and Interventional Radiology, Eberhard Karls University, 72076 Tübingen, Germany.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Nikolaou
authors.affiliation: Gerd Grözinger, Roland Syha, Dominik Ketelsen, Konstantin Nikolaou, Marius Horger, Department of Diagnostic and Interventional Radiology, Eberhard Karls University, 72076 Tübingen, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Lauer
authors.affiliation: Gerd Grözinger, Roland Syha, Dominik Ketelsen, Konstantin Nikolaou, Marius Horger, Department of Diagnostic and Interventional Radiology, Eberhard Karls University, 72076 Tübingen, Germany.
authors.forename: Marius
authors.initials: M
authors.lastname: Horger
keywords: Hepatocellular carcinoma; Magnetic resonance imaging; Volume perfusion computed tomography