title: Impact of splenic circulation: non-invasive microbubble-based assessment of portal hemodynamics.
abstract: OBJECTIVE
  The objective was to examine the effect of splenic circulation using a microbubble agent to assess the severity of portal hypertension.
  
  
  METHODS
  This prospective study consisted of 91 subjects (63.0 ± 12.6 years, 30-86; 60 males, 31 females), 62 cirrhosis and 29 controls, who underwent both Doppler ultrasound and contrast-enhanced ultrasound with a perflubutane microbubble agent. Two microbubble-based parameters for splenic circulation, the minimum circulation time (MCT, s) and the peak enhancement time (PET, s), were assessed with respect to the hepatic venous pressure gradient (HVPG) and other clinical findings.
  
  
  RESULTS
  The MCT and PET showed significant differences between cirrhosis (5.7 ± 1.8; 14.6 ± 3.0) and controls (4.0 ± 1.9, p < 0.0001; 8.9 ± 2.3, p < 0.0001), respectively. However, only PET offered positive correlations with wedged hepatic venous pressure (r = 0.4648, p = 0.0001) and HVPG (r = 0.4573, p = 0.0001). The area under the receiver operating characteristics curve to identify HVPG ≥ 10 mmHg, and 12 mmHg was 0.76 and 0.76, respectively.
  
  
  CONCLUSIONS
  The microbubble-based non-invasive assessment of the splenic circulation is effective to identify the severity of portal hypertension presumably by reflecting congestion of splenic venous flow due to increased portal venous pressure.
authors.affiliation: Department of Gastroenterology and Nephrology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670, Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Shimada
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Maruyama
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kondo
authors.forename: Tadashi
authors.initials: T
authors.lastname: Sekimoto
authors.forename: Masanori
authors.initials: M
authors.lastname: Takahashi
authors.forename: Osamu
authors.initials: O
authors.lastname: Yokosuka
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003287:Contrast Media; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D006975:Hypertension, Portal / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D045423:Microbubbles; D008875:Middle Aged; D011446:Prospective Studies; D012372:ROC Curve; D011877:Radionuclide Imaging; D013152:Splanchnic Circulation / Q000502:physiology*; D014463:Ultrasonography
chemical_list: D003287:Contrast Media