title: C-arm CT during hepatic arteriography tumour-to-liver contrast: intraindividual comparison of three different contrast media application protocols.
abstract: OBJECTIVE
  To compare tumour-to-liver contrast (TLC) of C-arm CT during hepatic arteriography (CACTHA) acquired using three protocols in patients with HCC.
  
  
  METHODS
  This prospective study was IRB approved and informed consent was obtained from each patient. Twenty-nine patients (mean age, 68 ± 7 years; 27 men) with 55 HCCs (mean diameter, 2.6 ± 1.5 cm) underwent three different CACTHA protocols in random order before chemoembolisation. Contrast medium (100 mg iodine/ml) was injected into the common hepatic artery (flow rate 4 ml/s). The imaging delay for the start of the CACTHA examination was 4 s (protocol A), 8 s (protocol B) and 12 s (protocol C) (total amount of injected contrast medium: 48 ml, 64 ml, 80 ml). TLC was measured by placing regions of interest (ROIs) in the HCC and liver parenchyma. Mixed model ANOVAs and Bonferroni corrected post hoc tests were used for statistical analysis.
  
  
  RESULTS
  Mean values for TLC were 132 ± 3.3 HU, 186 ± 5.8 HU and 168 ± 2.8 HU for protocols A, B and C. Protocol B provided significantly higher TLC than protocols A and C (p < 0.001).
  
  
  CONCLUSIONS
  TLC was significantly higher using an imaging delay of 8 s compared with a delay of 4 or 12 s.
authors.affiliation: Department of Radiology, Medical University of Vienna, Waehringer Geurtel 18-20, 1090 Vienna, Austria. claus.koelblinger@meduniwien.ac.at
authors.forename: Claus
authors.initials: C
authors.lastname: Koelblinger
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schima
authors.forename: Vanessa
authors.initials: V
authors.lastname: Berger-Kulemann
authors.forename: Florian
authors.initials: F
authors.lastname: Wolf
authors.forename: Christina
authors.initials: C
authors.lastname: Plank
authors.forename: Michael
authors.initials: M
authors.lastname: Weber
authors.forename: Johannes
authors.initials: J
authors.lastname: Lammer
mesh_terms: D000792:Angiography / Q000379:methods*; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007479:Iopamidol / Q000008:administration & dosage / Q000031:analogs & derivatives*; D008113:Liver Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; C057937:iomeprol; D007479:Iopamidol