title: Contrast-enhanced ultrasound in portal venous system aneurysms: a multi-center study.
abstract: OBJECTIVE
  To investigate contrast-enhanced ultrasound (CEUS) findings in portal venous system aneurysms (PVSAs).
  
  
  METHODS
  In this multi-center, retrospective, case series study, we evaluated CEUS features of seven cases of PVSAs that were found incidentally on conventional ultrasound in the period 2007-2013. Three Ultrasound Centers were involved (Chieti, Italy, Bad Mergentheim, Germany, and Cluj-Napoca, Romania). All patients underwent CEUS with Sonovue(®) (Bracco, Milan, Italy) at a standard dose of 2.4 mL, followed by 10 mL of 0.9% saline solution. The examinations were performed using multifrequency transducers and low mechanical index. We considered aneurysmal a focal dilatation of the portal venous system with a size that was significantly greater than the remaining segments of the same vein, and that was equal or larger than 21 mm for the extrahepatic segments of portal venous system, main portal vein and bifurcation, and 9 mm for the intrahepatic branches.
  
  
  RESULTS
  After contrast agent injection, all PVSAs were not enhanced in the arterial phase (starting 8-22 s). All PVSAs were then rapidly enhanced in the early portal venous phase (starting three to five seconds after the arterial phase, 11-30 s), with persistence and slow washout of the contrast agent in the late phase (starting 120 s). In all patients, CEUS confirmed the presence of a "to-and-fro" flow by showing a swirling pattern within the dilatation in the early portal venous phase. CEUS also improved the delineation of the lumen, and was reliable in showing its patency degree and integrity of walls. In one patient, CEUS showed a partial enhancement of the lumen with a uniformly nonenhancing area in the portal venous and late phases, suggesting thrombosis.
  
  
  CONCLUSIONS
  In our case series, we found that CEUS could be useful in the assessment and follow-up of a PVSA. Further studies are needed to validate its diagnostic accuracy.
authors.affiliation: Claudio Tana, Vincenzo Carrieri, Cosima Schiavone, Unit of Internistic Ultrasound, Department of Medicine and Science of Aging, "G. d'Annunzio" University, 66100 Chieti, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Tana
authors.affiliation: Claudio Tana, Vincenzo Carrieri, Cosima Schiavone, Unit of Internistic Ultrasound, Department of Medicine and Science of Aging, "G. d'Annunzio" University, 66100 Chieti, Italy.
authors.forename: Christoph F
authors.initials: CF
authors.lastname: Dietrich
authors.affiliation: Claudio Tana, Vincenzo Carrieri, Cosima Schiavone, Unit of Internistic Ultrasound, Department of Medicine and Science of Aging, "G. d'Annunzio" University, 66100 Chieti, Italy.
authors.forename: Radu
authors.initials: R
authors.lastname: Badea
authors.affiliation: Claudio Tana, Vincenzo Carrieri, Cosima Schiavone, Unit of Internistic Ultrasound, Department of Medicine and Science of Aging, "G. d'Annunzio" University, 66100 Chieti, Italy.
authors.forename: Liliana
authors.initials: L
authors.lastname: Chiorean
authors.affiliation: Claudio Tana, Vincenzo Carrieri, Cosima Schiavone, Unit of Internistic Ultrasound, Department of Medicine and Science of Aging, "G. d'Annunzio" University, 66100 Chieti, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Carrieri
authors.affiliation: Claudio Tana, Vincenzo Carrieri, Cosima Schiavone, Unit of Internistic Ultrasound, Department of Medicine and Science of Aging, "G. d'Annunzio" University, 66100 Chieti, Italy.
authors.forename: Cosima
authors.initials: C
authors.lastname: Schiavone
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000783:Aneurysm / Q000000981:diagnostic imaging*; D003287:Contrast Media; D004108:Dilatation, Pathologic; D005060:Europe; D005260:Female; D006801:Humans; D033162:Incidental Findings; D008297:Male; D008875:Middle Aged; D010743:Phospholipids; D011169:Portal Vein / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D013459:Sulfur Hexafluoride; D018615:Ultrasonography, Doppler, Color
chemical_list: D003287:Contrast Media; D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride
keywords: Aneurysm; Computed tomography; Contrast-enhanced ultrasound; Magnetic resonance imaging; Portal vein; Venous system