Portosystemic shunt surgery in the era of TIPS: imaging-based planning of the surgical approach

Abstract

Purpose: With the spread of transjugular intrahepatic portosystemic shunts (TIPS), portosystemic shunt surgery (PSSS) has decreased and leaves more complex patients with great demands for accurate preoperative planning. The aim was to evaluate the role of imaging for predicting the most suitable PSSS approach.

Material and methods: Forty-four patients who underwent PSSS (2002 to 2013) were examined by contrast-enhanced CT (n = 33) and/or MRI (n = 15) prior to surgery. Imaging was analyzed independently by two observers (O1 and O2) with different levels of experience (O1 > O2). They recommended two shunting techniques (vessels and anastomotic variant) for each patient and ranked them according to their appropriateness and complexity. Findings were compared with the actually performed shunt procedure and its outcome.

Results: The first two choices taken together covered the performed PSSS regarding vessels in 88%/100% (CT/MRI, O1) and 76%/73% (O2); and vessels + anastomosis in 79%/73% (O1) and 67%/60% (O2). The prediction of complex surgical procedures (resection of interposing structures, additional thrombectomy, use of a collateral vessel, and use of a graft interposition) was confirmed in 87%, resulting in 80% sensitivity and 96% specificity. Larger shunt vessel distances were associated with therapy failure (p = 0.030) and a vessel distance of ≥ 20 mm was identified as optimal cutoff, in which a graft interposition was used. There was no significant difference between MRI and CT in predicting the intraoperative decisions (p = 0.294 to 1.000).

Conclusion: Preoperative imaging and an experienced radiologist can guide surgeons in PSSS. CT and MRI provide the information necessary to identify technically feasible variants and complicating factors.

Keywords: Computed tomography; Magnetic resonance imaging; Portal hypertension; Portosystemic shunt surgery.

Fig. 1

Flowchart of retrospective enrollment

Fig. 2

A 17-year-old female PHT patient with Wilson’s disease and recurrent variceal bleeding—PSSS procedure: portacaval side-to-side; a preoperative MRI, post-contrast T1-w, b postoperative MRI, post-contrast T1-w and c postoperative MRI, T2w. Small arrow: IVC; arrowhead: portal vein; bold arrow: portacaval anastomosis

Fig. 3

A 71-year-old male PHT patient with excessive ascites after extended right hemihepatectomy (diagnosis: intrahepatic cholangiocarcinoma)—PSSS: splenorenal side-to-side; a preoperative CT, oblique MIP reconstruction and b postoperative CT, oblique MIP reconstruction. Small arrow: left renal vein; arrowhead: splenic vein; bold arrow: splenorenal anastomosis

Fig. 4

A 49-year-old male PHT patient with liver cirrhosis, extrahepatic portal vein thrombosis, and advanced symptoms—PSSS procedure: mesocaval; a preoperative CT, b postoperative CT, axial MIP reconstruction and c postoperative CT, sagittal MIP reconstruction. Small arrow: IVC; arrowhead: SMV; bold arrow: mesocaval anastomosis

Fig. 5

Factors of complexity. a Oblique axial CT (fused portal venous phase and venous phase) shows an intervening caudate lobe (PSSS procedure: portacaval end-to-side with subsegmental liver resection); bold arrow: caudate lobe; arrowhead: portal vein; small arrow: hepatic artery; asterisk: IVC. b Axial CT with partial thrombosis of the extrahepatic portal vein (PSSS procedure: portacaval side-to-side after thrombectomy). c Oblique coronal CT MIP shows a large distance of 29 mm between IVC (small arrow) and superior mesenteric vein (arrowhead). In this patient, an allograft was interposed as seen in d (PSSS procedure: mesocaval with graft interposition). d Postoperative oblique coronal CT MIP reconstruction shows the interposed graft (bold arrow) connecting the SMV (arrowhead) and IVC (small arrow)

Fig. 6

ROC analysis—distance of connected vessels and need for graft interposition; AUC 0.950 (p < 0.001); max. Youden index 0.771 at 20 mm