Published online Mar 6, 2020. doi: 10.12998/wjcc.v8.i5.887
Peer-review started: November 19, 2019
First decision: December 23, 2015
Revised: January 19, 2020
Accepted: February 12, 2020
Article in press: February 12, 2020
Published online: March 6, 2020
Processing time: 107 Days and 21.1 Hours
Cavernous transformation of the portal vein (CTPV) occurs after portal vein thrombosis or intrahepatic venous collateral formation. Sequelae of CTPV can include portal hypertension, splenomegaly, ascites, gastrointestinal varices, obstructive jaundice, mesenteric venous congestion and ischaemia, ascending cholangitis, and biliary cirrhosis. Insertion of transjugular intrahepatic portosystemic shunt (TIPS) can reconstruct portal venous flow, reduce portal hypertension, and decrease the incidence of variceal rebleeding. However, the occluded portal vein becomes difficult to access by the transjugular route. Computed tomography (CT) is widely used for assessing the venous situation of the portal vein and its tributaries before TIPS, and an ultrasound-based Yerdel grading system has been developed, which is deemed useful for liver transplantation.
We aimed to investigate a simple CT-based CTPV scoring system that could be useful for predicting technical and midterm outcomes in TIPS treatment for symptomatic portal cavernoma.
Our main purpose was to develop a CT-based model/nomogram that amalgamated the clinical factors for individual preoperative prediction of TIPS treatment for symptomatic CTPV, including technical success rate, stent patency rate, and midterm survival, which might aid interventional radiologists in therapeutic decision-making.
We carried out a retrospective observational single-centre study. A total of 76 patients treated between January 2010 and December 2017 were analysed. The patients were divided into two groups: TIPS success and failure groups. The CTPV was graded with a score of 1-4 based on contrast-CT imaging findings of the portal vein. Outcome measures were technical success rate, stent patency rate, and midterm survival. Cohen’s kappa, the Kaplan-Meier and log-rank tests, and uni- and multivariable analyses were performed. A nomogram was constructed and verified by calibration and decision curve analysis.
The inter-reader agreement (κ) of the two readers for the CTPV score was 0.81. Of note, as the CTPV score increased, technical success was found to decrease despite increased use of assisted puncture (χ2 = 12.1, Ptrend = 0.031). The only independent predictor of TIPS success was CTPV score. The independent predictors of primary shunt dysfunction were CTPV score and splenectomy. The survival rates differed significantly between the TIPS success and failure groups. The clinical nomogram was made up of patient age, model for end-stage liver disease score, and CTPV score. The calibration curves and decision curve analysis verified the usefulness of the CTPV score-based nomogram for clinical practice.
In conclusion, our results suggest that clinicians could use this simple grading system to select appropriate patients and therefore maintain a relatively high technical success rate. In addition, the independent predictors of shunt dysfunction were CTPV and splenectomy. Finally, as our CTPV score-based nomogram exhibits a high prognostic predictive value, we believe that this simple CT-based score model/nomogram could be useful in decision-making for interventional radiologists who could perform the TIPS procedure on patients with symptomatic portal cavernoma.
Further large-scale prospective studies are needed. We will compare TIPS exclusive stents (Viatorr) with covered self-expanding stents (Fluency) in future research.