Ex vivo cholangioscopy in liver grafts: a novel technique to assess the biliary tree during organ preservation and machine perfusion: a experimental non-clinical study.

Background/aims: Biliary complications are a leading cause of morbidity after liver transplantation, but can be reduced using real-time assessment of the biliary tree. This study described a novel technique for performing ex vivo cholangioscopy during cold static storage and normothermic machine perfusion (NMP) to assess the biliary tree before liver transplantation.

Methods: Human donor livers, which were considered unsuitable for transplantation, were perfused at 36ºC using a modified commercial ex vivo perfusion system. Ex vivo cholangioscopy was performed using a SpyGlass Discover system. Cholangioscopy was performed during cold static storage and after 12 hours in NMP. Bile duct biopsies and confocal microscopy were performed.

Results: Ex vivo cholangioscopy was performed on eight grafts. During cold static storage, luminal debris was visualized throughout the biliary tree. After 12 hours of reperfusion, the bile ducts appeared hyperemic, heterogeneous, and mottled. Confocal microscopy confirmed perfusion of biliary microvasculature.

Conclusions: We describe the first use of ex vivo cholangioscopy to assess the biliary tree before liver transplantation. This real-time technique can be used to assess biliary trees during cold static storage and NMP. In addition, cholangioscopy-based interventions can be used to better assess intrahepatic bile ducts.