title: Prospective Evaluation of Passive Expansion of Partially Dilated Transjugular Intrahepatic Portosystemic Shunt Stent Grafts-A Three-Dimensional Sonography Study.
abstract: OBJECTIVE
  To prospectively investigate early expansion kinetics of underdilated self-expanding stent grafts used for transjugular intrahepatic portosystemic shunt (TIPS) creation.
  
  
  METHODS
  Twenty patients (7 female; mean age 66 y; range, 31-80 y) with liver cirrhosis undergoing TIPS creation for variceal bleeding (n = 5), refractory ascites (n = 14), or both (n = 1) with underdilation of 10-mm stent grafts received two-dimensional (2-D) and three-dimensional (3-D) ultrasound (US) examinations immediately after TIPS creation and 1 and 6 weeks later. Orthogonal views of the TIPS within the parenchymal tract were reconstructed from 3-D volume data sets acquired in longitudinal orientation of the stent. 2-D images and reconstructed 3-D images were used for blinded diameter measurements. Measurement technique was validated with intrainterventional plain radiographs with a sizing catheter as the gold standard. Diameter changes over time and interrelations with patient characteristics (null hypothesis: no expansion, no interrelation) were analyzed using a general linear model for repeated measures.
  
  
  RESULTS
  After dilation to 8-mm diameter, 2-D and 3-D measurements showed stent recoil (mean diameter 7.7 mm ± 0.21 and 7.6 mm ± 0.17, respectively). Diameter increased significantly from initial measurements to measurements at 1 and 6 weeks (2-D, 8.8 mm ± 0.24 and 9.4 mm ± 0.15, both P < .001; 3-D, 8.7 mm ± 0.27 and 9.4 mm ± 0.11, both P < .001). Validation measurements showed no significant differences between 2-D or 3-D US and gold standard. There were no statistically significant associations between stent expansion and clinical parameters (sex, P = .78; age, P = .82; etiology/grade of cirrhosis, P = .99; indication for TIPS, P = .78, liver stiffness, P = .70).
  
  
  CONCLUSIONS
  Underdilated self-expanding stent grafts used for TIPS creation significantly expand within first 6 weeks after intervention. These changes can be noninvasively monitored using 3-D US.
authors.affiliation: Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, Bonn 53105, Germany.
authors.forename: Claus Christian
authors.initials: CC
authors.lastname: Pieper
authors.affiliation: Department of Internal Medicine I, University of Bonn, Sigmund-Freud-Strasse 25, Bonn 53105, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Jansen
authors.affiliation: Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, Bonn 53105, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Meyer
authors.affiliation: Institute for Medical Biometry, Informatics and Epidemiology, University of Bonn, Sigmund-Freud-Strasse 25, Bonn 53105, Germany.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Nadal
authors.affiliation: Department of Internal Medicine I, University of Bonn, Sigmund-Freud-Strasse 25, Bonn 53105, Germany.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Lehmann
authors.affiliation: Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, Bonn 53105, Germany.
authors.forename: Hans Heinz
authors.initials: HH
authors.lastname: Schild
authors.affiliation: Department of Internal Medicine I, University of Bonn, Sigmund-Freud-Strasse 25, Bonn 53105, Germany.
authors.forename: Jonel
authors.initials: J
authors.lastname: Trebicka
authors.affiliation: Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, Bonn 53105, Germany. Electronic address: daniel.thomas@ukb.uni-bonn.de.
authors.forename: Daniel
authors.initials: D
authors.lastname: Thomas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001201:Ascites / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D004932:Esophageal and Gastric Varices / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007700:Kinetics; D008103:Liver Cirrhosis / Q000150:complications; D008297:Male; D008875:Middle Aged; D019168:Portasystemic Shunt, Transjugular Intrahepatic / Q000009:adverse effects / Q000295:instrumentation*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011474:Prosthesis Design; D015203:Reproducibility of Results; D015607:Stents; D016896:Treatment Outcome; D014463:Ultrasonography