title: Characterization of hepatocellular carcinoma (HCC) lesions using a novel CT-based volume perfusion (VPCT) technique.
abstract: OBJECTIVE
  To characterize hepatocellular carcinoma (HCC) in terms of perfusion parameters using volume perfusion CT (VPCT) and two different calculation methods, compare their results, look for interobserver agreement of measurements and correlation between tumor arterialization and lesion size.
  
  
  METHODS
  This study was part of a prospective monitoring study in patients with HCC undergoing TACE, which was approved by the local Institutional Review Board. 79 HCC-patients (mean age, 64.7) with liver cirrhosis were enrolled. VPCT was performed for 40s covering the involved liver (80 kV, 100/120 mAs) using 64 mm × 0.6 mm collimation, 26 consecutive volume measurements, 50 mL iodinated contrast IV and 5 mL/s flow rate. Mean/maximum blood flow (BF; ml/100mL/min), blood volume (BV) and k-trans were determined both with the maximum slope+Patlak vs. deconvolution method. Additionally, the portal venous liver perfusion (PVP), the arterial liver perfusion (ALP) and the hepatic perfusion index (HPI) were determined for each tumor including size measurements. Interobserver agreement for all perfusion parameters was calculated using intraclass correlation coefficients (ICC).
  
  
  RESULTS
  The max. slope+Patlak method yielded: BFmean/max=37.8/57 mL/100g-tissue/', BVmean/max=9.8/11.1 mL/100g-tissue, k-trans-mean/max=34.4/44.5 mL/100g-tissue/'. For the deconvolution method BFmean/max, BVmean/max and, k-trans-mean/max were 68.3/106.1 mL/100g-tissue/', 12.6/15.5 mL/100g-tissue and 24/33.8 mL/100g-tissue/'. Mean ALP, PVP, HPI and size were 53.7 mL/100g-tissue/', 2.4 mL/100g-tissue/', 96.4 and 3.5 cm, respectively. Interobserver agreement measured with intraclass coefficient correlation (ICC) was very good for all perfusion parameters (≥ 0.99). Best correlation between calculation methods was achieved for measurements of BF, while BV and k-trans values were less correlated. There was no relationship between HPI and lesion size.
  
  
  CONCLUSIONS
  VPCT can measure tumor volume perfusion non-invasively and enables quantification of the degree of HCC arterialization. Results are dependent on the technique used with best inter-method correlation for BF. Tumor HPI did not proved size-dependent.
authors: Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Strasse 3, 72076 Tübingen, Germany. Electronic address: sascha.kaufmann@med.uni-tuebingen.de.
authors: S
authors: S
authors: Kaufmann
authors: Technische Universität München, Boltzmannstraße 3, 85748 Garching, Germany. Electronic address: horger@ma.tum.de.
authors: T
authors: T
authors: Horger
authors: Technische Universität München, Boltzmannstraße 3, 85748 Garching, Germany. Electronic address: oelker@ma.tum.de.
authors: A
authors: A
authors: Oelker
authors: Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Strasse 3, 72076 Tübingen, Germany. Electronic address: christopher.kloth@med.uni-tuebingen.de.
authors: C
authors: C
authors: Kloth
authors: Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Strasse 3, 72076 Tübingen, Germany. Electronic address: Konstantin.Nikolaou@med.uni-tuebingen.de.
authors: K
authors: K
authors: Nikolaou
authors: Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Strasse 3, 72076 Tübingen, Germany. Electronic address: maximilian.schulze@med.uni-tuebingen.de.
authors: M
authors: M
authors: Schulze
authors: Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Strasse 3, 72076 Tübingen, Germany. Electronic address: marius.horger@med.uni-tuebingen.de.
authors: M
authors: M
authors: Horger
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000473:pathology; D054893:Cone-Beam Computed Tomography; D003287:Contrast Media; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging* / Q000473:pathology; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging*; D055420:Perfusion Imaging / Q000379:methods; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media
keywords: Hepatocellular carcinoma; Pharmacokinetic; Tumor characterization; Volume perfusion CT (VPCT)