Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification

Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.

Sonographic features of umbilical vein recanalization for a Rex shunt on cavernous transformation of portal vein in children

BACKGROUND The Rex shunt was widely used as the preferred surgical approach for cavernous transformation of the portal vein(CTPV)in children that creates a bypass between the superior mesenteric vein and the intrahepatic left portal vein(LPV).This procedure can relieve portal hypertension and restore physiological hepatopetal flow.However,the modified procedure is technically demanding because it is difficult to make an end-to-end anastomosis of a bypass to a hypoplastic LPV.Many studies reported using a recanalized umbilical vein as a conduit to resolve this problem.However,the feasibility of umbilical vein recanalization for a Rex shunt has not been fully investigated.AIM To investigate the efficacy of a recanalized umbilical vein as a conduit for a Rex shunt on CTPV in children by ultrasonography.METHODS A total of 47 children who were diagnosed with CTPV with prehepatic portal hypertension in the Second Hospital,Cheeloo College of Medicine,Shandong University,were enrolled in this study.Fifteen children received a recanalized umbilical vein as a conduit for a Rex shunt surgery and were enrolled in group I.Thirty-two children received the classic Rex shunt surgery and were enrolled in group II.The sonographic features of the two groups related to intraoperative and postoperative variation in terms of bypass vessel and the LPV were compared.RESULTS The patency rate of group I(60.0%,9/15)was significantly lower than that of group II(87.5%,28/32)7 d after(on the 8th d)operation(P<0.05).After clinical anticoagulation treatment for 3 mo,there was no significant difference in the patency rate between group I(86.7%,13/15)and group II(90.6%,29/32)(P>0.05).Moreover,3 mo after(at the beginning of the 4th mo)surgery,the inner diameter significantly widened and flow velocity notably increased for the bypass vessels and the sagittal part of the LPV compared to intraoperative values in both shunt groups(P<0.05).However,there was no significant difference between the two surgical groups 3 mo after surgery(P>0.05).CONCLUSION For children with hypoplastic LPV in the Rex recessus,using a recanalized umbilical vein as a conduit for a Rex shunt may be an effective procedure for CTPV treatment.

Nakao mesenteric approach in pancreatoduodenectomy for pancreatic head cancer

The ideal surgery for pancreatic head cancer is isolated pancreatoduodenectomy(PD);that is,en bloc resection using a non-touch isolation technique.We have been developing isolated PD for pancreatic cancer since 1981,when we developed an antithrombogenic bypass catheter for the portal vein.In this operation,the first and most important step is the use of a mesenteric approach instead of Kocher’s maneuver.The mesenteric approach allows dissection from the non-cancer infiltrating side and determination of cancer-free surgical margins and resectability,followed by systemic lymphadenectomy around the superior mesenteric artery.This approach enables early ligation of the inferior pancreatoduodenal artery and mesopancreas excision.The mesopancreas is the second portion of the pancreatic head nerve plexus.Isolated PD is the ideal surgery for pancreatic head cancer from both surgical and oncological viewpoints.In patients with resectable pancreatic head cancer,isolated PD using the mesenteric approach is suspected to have a higher survival rate than conventional PD using Kocher’s maneuver.The precise surgical techniques of the mesenteric approach are herein described.