Extrahepatic portal vein occlusion is classified as primary or secondary, and causes such as abdominal surgery, like PD, are secondary. The causes of extrahepatic portal vein obstruction after PD include postoperative portal vein thrombosis, periportal adhesions, inflammation due to lymph node dissection or anastomotic leakage, and tumor recurrence around the portal vein [2]. One report noted that a postoperative pancreatic fistula was an independent risk factor for benign PV stenosis after PD [7]. In this case, there was a grade A pancreatic fistula after PD surgery, which was considered as a cause of the portal vein stenosis. As long-term survival after PD has become possible [1], late complications include varicose vein formation and gastrointestinal bleeding due to stenosis or occlusion of the portal vein.
Ectopic variceal bleeding is generally massive and life-threatening with a mortality rate of approximately 40%. Up to 17% of ectopic varices occur in the duodenum [8]. Varicose veins of the jejunum after PD are often challenging to reach using an endoscope, making diagnosis difficult. Additionally, endoscopic hemostasis is difficult. However, DB enteroscopy has recently made it possible to visualize and diagnose varicose veins [9]. Here, we identified vasodilatation near the hepaticojejunostomy site using DB enteroscopy resulting in the diagnosis.
Endoscopic treatment of varices of the jejunum in the presence of portal vein stenosis causes hepatofugal portal venous flow, resulting in the exacerbation of esophagogastric varices and bleeding. Repeated bleeding from the jejunum and gastroesophageal varices after endoscopic treatment of portal vein stenosis patients have been reported [10]. Unlike esophageal varices in cirrhosis, the endoscopic hemostatic effect of hepatopetal jejunal varices due to extrahepatic portal vein obstruction is short-lived, and other means of hemostasis are required. Therefore, it is important to treat portal stenosis, which is the essence of the disease, and to lower portal pressure as a fundamental treatment procedure. Recently, an increasing number of reports have noted that portal vein stenting and transjugular intrahepatic portosystemic shunt (TIPS) are less invasive, more physiological, and more practical than revascularization. Portal vein stenting has improved clinical symptoms in over 80% of cases [3, 11]. However, there have been some reports of patients experiencing gastrointestinal bleeding after stenting, and the average patency period has been reported as 6 days to 29 months [12], which is not long enough for long-term patency. TIPS was not applicable in this case because of extrahepatic portal vein obstruction.
Surgical revascularization includes a Rex shunt and a portosystemic shunt. In the portosystemic shunt, the shunting site and anastomosis method can be selected according to the situation [10]. The efficacy of the portosystemic shunt for varicose veins has been reported to be 100% while the efficacy of the Rex shunt has been reported to be 96% [13]. The Rex shunt for adults with severe adhesions due to PD has been less common because of its difficulty and complexity [14]. A spleno-renal or inferior mesenteric–renal vein shunt was not recommended due to stenosis of the splenic and inferior mesenteric veins [15]. Therefore, we performed a portosystemic shunt (SMV–IVC) using a testicular vein as the shunt vessel without a graft. To our knowledge, this is the first case of a portosystemic shunt using the testicular vein. This shunting procedure is performed caudal to the transverse mesentery, so postoperative adhesions were not a concern. Additionally, the right testicular vein ran dorsal to the small mesentery, allowing for a relatively long neurovascular pedicle that could be freely anastomosed with the SMV. Moreover, it has been reported that distal splenic renal shunting for portal vein stenosis preserved hepatic portal blood flow in 88–90% of cases in the early postoperative period, suggesting that portal blood flow is less affected and the risk of hepatic encephalopathy is lower than for major shunting operations, such as a portal–IVC shunt [16, 17]. In this case, portal pressure was maintained at 22 mmHg after the bypass surgery, suggesting that the portosystemic shunt using the testicular vein worked similarly to a selective shunting procedure such as a distal spleno-renal shunt. Therefore, it is considered to have a lower risk of hepatic encephalopathy than significant shunts.