title: Intrahepatic portal vein blood volume estimated by non-contrast magnetic resonance imaging for the assessment of portal hypertension.
abstract: OBJECTIVE
  To investigate the feasibility of estimating the portal vein blood volume that flows into the intrahepatic volume (IHPVBV) in each cardiac cycle using non-contrast MR venography technique as a surrogate marker of portal hypertension (PH).
  
  
  METHODS
  Ten patients with chronic liver disease and clinical symptoms of PH (40% males, median age: 54.0, range: 44-73 years old) and ten healthy volunteers (80% males, median age: 54.0, range: 44-66 years old) were included in this study. A non-contrast Triple-Inversion-Recovery Arterial-Spin-Labeling (TIR-ASL) technique was used to quantify the IHPVBV in one and two cardiac cycles. Liver (LV) and spleen volumes (SV) were measured by manual segmentation from anatomical MR images as morphological markers of PH. All images were acquired in a 1.5T Philips Achieva MR scanner.
  
  
  RESULTS
  PH patients had larger SV (P=0.02) and lower liver-to-spleen ratio (P=0.02) compared with healthy volunteers. The median IHPVBV in healthy volunteers was 13.5cm(3) and 26.5cm(3) for one and two cardiac cycles respectively, whereas in PH patients a median volume of 3.1cm(3) and 9.0cm(3) was observed. When correcting by LV, the IHPVBV was significantly higher in healthy volunteers than PH patients for one and two cardiac cycles. The combination of morphological information (liver-to-spleen ratio) and functional information (IHPVBV/LV) can accurately identify the PH patients with a sensitivity of 90% and specificity of 100%.
  
  
  CONCLUSIONS
  Results show that the portal vein blood volume that flows into the intrahepatic volume in one and two cardiac cycles is significantly lower in PH patients than in healthy volunteers and can be quantified with non-contrast MRI techniques.
authors.affiliation: Biomedical Imaging Center, Pontificia Universidad Catolica de Chile, Santiago, 7820436, Chile; Electrical Engineering Department, School of Engineering, Pontificia Universidad Catolica de Chile, Santiago, 7820436, Chile; Computation Sciences and Electronic Department, Universidad Tecnica Particular de Loja, Ecuador, Loja 1101608, Ecuador. Electronic address: dfaguirre@uc.cl.
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Aguirre-Reyes
authors.affiliation: Biomedical Imaging Center, Pontificia Universidad Catolica de Chile, Santiago, 7820436, Chile; Electrical Engineering Department, School of Engineering, Pontificia Universidad Catolica de Chile, Santiago, 7820436, Chile. Electronic address: jasotelo@uc.cl.
authors.forename: Julio A
authors.initials: JA
authors.lastname: Sotelo
authors.affiliation: Gastroenterology Department, School of Medicine, Pontificia Universidad Catolica de Chile, Santiago, 8331150, Chile. Electronic address: jparab@gmail.com.
authors.forename: Juan P
authors.initials: JP
authors.lastname: Arab
authors.affiliation: Gastroenterology Department, School of Medicine, Pontificia Universidad Catolica de Chile, Santiago, 8331150, Chile. Electronic address: marco.arrese@gmail.com.
authors.forename: Marco
authors.initials: M
authors.lastname: Arrese
authors.affiliation: Gastroenterology Department, School of Medicine, Pontificia Universidad Catolica de Chile, Santiago, 8331150, Chile. Electronic address: ratejos@uc.cl.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Tejos
authors.affiliation: Biomedical Imaging Center, Pontificia Universidad Catolica de Chile, Santiago, 7820436, Chile; Electrical Engineering Department, School of Engineering, Pontificia Universidad Catolica de Chile, Santiago, 7820436, Chile. Electronic address: pim@ing.puc.cl.
authors.forename: Pablo
authors.initials: P
authors.lastname: Irarrazaval
authors.affiliation: Biomedical Imaging Center, Pontificia Universidad Catolica de Chile, Santiago, 7820436, Chile; Electrical Engineering Department, School of Engineering, Pontificia Universidad Catolica de Chile, Santiago, 7820436, Chile. Electronic address: ctejos@puc.cl.
authors.forename: Cristian
authors.initials: C
authors.lastname: Tejos
authors.affiliation: Biomedical Imaging Center, Pontificia Universidad Catolica de Chile, Santiago, 7820436, Chile; Radiology Department, School of Medicine, Pontificia Universidad Catolica de Chile, Santiago, 8331150, Chile. Electronic address: suribe@med.puc.cl.
authors.forename: Sergio A
authors.initials: SA
authors.lastname: Uribe
authors.affiliation: Biomedical Imaging Center, Pontificia Universidad Catolica de Chile, Santiago, 7820436, Chile; Radiology Department, School of Medicine, Pontificia Universidad Catolica de Chile, Santiago, 8331150, Chile. Electronic address: mandia@med.puc.cl.
authors.forename: Marcelo E
authors.initials: ME
authors.lastname: Andia
mesh_terms: D000328:Adult; D000368:Aged; D001810:Blood Volume; D001811:Blood Volume Determination / Q000379:methods*; D003287:Contrast Media; D005260:Female; D006801:Humans; D006975:Hypertension, Portal / Q000175:diagnosis* / Q000503:physiopathology*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011169:Portal Vein / Q000473:pathology / Q000503:physiopathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media
keywords: Arterial spin labeling; Cirrhosis; Intrahepatic portal vein; Non-contrast MRI; Portal hypertension