ORIGINAL ARTICLE An Extrahepatic Bile Duct Grafting Using a Bioabsorbable Polymer Tube Masayasu Aikawa & Mitsuo Miyazawa & Kojun Okamoto & Yasuko Toshimitsu & Katsuya Okada & Naoe Akimoto & Yosuke Ueno & Isamu Koyama & Yoshito Ikada Received: 14 July 2011 / Accepted: 14 December 2011 / Published online: 6 January 2012 # 2011 The Society for Surgery of the Alimentary Tract Abstract Background Thus far, no ideal substitutions have been developed for completely replacing the extrahepatic bile duct (EHBD). Methods We used a bioabsorbable polymer tube (BAPT) for the complete reconstruction of an EHBD in pigs. A 2-cm-long EHBD was resected from the duodenal side, and a 4-cm-long BAPT graft was implanted at that site. The animals were re- laparotomized at 1 or 4 months after the grafting; subsequently, gross, histological, and blood chemical studies were performed. Results At 1 month after grafting, tubular structure was observed in all resected specimens, and the lumen of the graft site had remnants of degraded BAPT. Gross examination at 4 months after grafting revealed that the BAPT had been completely absorbed, and the graft site was indistinguishable from the native extrahepatic bile duct. The lengths of the graft region at 4 months were 70% of the replaced BAPT. Simultaneously performed histological examination revealed the growth of a neo- bile duct at the graft site, with an epithelium identical to that of the native bile duct. Conclusion The BAPT graft implanted in this study completely replaced the EHBD defect. Hence, BAPT has the potential for application as a novel treatment modality for hepatobiliary diseases. Keywords Bioabsorbable polymer . Extrahepatic bile duct . Biliary reconstruction . Choledochoenterostomy . Regenerative therapy Introduction Benign biliary strictures are occasionally encountered after laparoscopic cholecystectomy and living-donor liver transplantation. These complications may often recur and lead to long-term deterioration of the quality of life of patients. 1–3 Tumors localized to the extrahepatic bile duct (EHBD) can be detected with advanced imaging modalities and radically resected by removing the EHBD. 4 Biliary enteric anastomosis is a common type of biliary reconstruction applied after surgi- cal resection of a biliary tract lesion. However, after this procedure, patients are susceptible to retrograde cholangitis because this procedure inhibits the mechanism by which the duodenal papilla prevents reflux. 5–7 Further, if retrograde chol- angitis persists and is untreated over a long period, it can induce cholangiocarcinoma. 8–11 Given the risk of these out- comes, biliary reconstruction by biliary enteric anastomosis cannot be considered as an ideal treatment for EHBD lesions. In a previous study, we developed a bioabsorbable polymer tube (BAPT) capable of regenerating the bile duct. 12 In that study, we showed that a bypass could be established between the extrahepatic bile duct and duodenum. However, because no substitutes were needed to establish a bypass between the bile duct and duodenum, we could not determine if BAPT had a potential clinical use in hepatobiliary pancreatic surgery. M. Aikawa : M. Miyazawa (*) : K. Okamoto : Y. Toshimitsu : K. Okada : N. Akimoto : Y. Ueno : I. Koyama Gastrointestinal Center, Department of Surgery, Saitama Medical University, International Medical Center, 1397-1 Yamane, Hidaka, Saitama 350-1298, Japan e-mail: miyazawa32000@yahoo.co.jp M. Aikawa e-mail: aikawama@ybb.ne.jp Y. Ikada Division of Life Science, Nara Medical University, Nara, Japan J Gastrointest Surg (2012) 16:529–534 DOI 10.1007/s11605-011-1801-6