Main portal vein access in transjugular intrahepatic portosystemic shunt procedures: use of three-dimensional ultrasound to ensure safety.

PURPOSE

To document the safety of main portal vein (PV) access to create transjugular portosystemic intrahepatic shunts (TIPS), provided that three-dimensional ultrasonography (3D US) can document the puncture to have entered a surface of the PV suitable for tamponade.

MATERIALS AND METHODS

In 11 patients who underwent conventional TIPS creation (n = 10) or a transjugular portacaval shunt procedure (n = 1), the puncture was found angiographically to enter the main PV. In seven cases, this occurred at the PV bifurcation and, in four, it occurred in the superior third of the PV. 3D US was used to determine whether the point of PV entry was functionally intrahepatic or extrahepatic. The puncture site was deemed to be intrahepatic if liver covered the puncture site on all three orthogonal imaging planes (sagittal, coronal, and transverse). If the puncture site was surrounded by liver, the access was used to deploy a metallic stent (uncovered, n = 10; covered, n = 1). Medical records and follow-up cross-sectional imaging studies were reviewed for evidence of hemorrhage complications. Pathologic correlation was performed in one explanted liver and autopsy specimens in five other patients.

RESULTS

In nine of 11 patients, 3D US was diagnostic and confidently verified that liver completely covered the portal vein access site. In two patients with diagnostically uncertain 3D US results, transcatheter injection of contrast medium documented no extravasation. All TIPS and direct portacaval shunt procedures were technically successful. No hemorrhagic complications occurred. Examination of pathologic specimens documented this portion of the portal vein to be extraperitoneal, but attached to the superior surface of the caudate lobe with fibrous tissue and small portal vein branches.

CONCLUSIONS

The bifurcation and posterior aspect of the superior third of the main PV can be safely used for TIPS procedures, provided access is proven to be surrounded by liver. 3D US can usually confidently determine if the PV entry site is functionally intrahepatic.