The Role of Fluorescent Cholangiography to Improve Operative Safety in Different Severity Degree of Acute Cholecystitis During Emergency Laparoscopic Cholecystectomy.

The study aims to to evaluate the efficacy of near-infrared fluorescent cholangiography for real-time visualization of the extrahepatic biliary tree (cystic duct, common hepatic duct, cystic duct-common hepatic duct junction, common bile duct and any accessory or aberrant ducts) in emergency laparoscopic cholecystectomy before and after hepatocystic triangle dissection and in different degrees of severity of acute cholecystitis according to the American Association of Surgery for Trauma (AAST) classification, specifically distinguishing between non-gangrenous (grade I) and gangrenous or complicated (grades II-V) forms. For intra-operative fluorescent cholangiography, 2.5 mg indocyanine green (ICG) was administered intravenously 45-60 min prior to surgery, according to the recent guidelines from the International Society for Fluorescence Guided Surgery. All the operations were performed by the same team of surgeons. Near-infrared fluorescent cholangiography was performed by using Stryker's fluorescence imaging system (Stryker, Portage, Miami, USA). Near-infrared fluorescent cholangiography was performed at three defined time point during laparoscopic cholecystectomy: (i) following exposure of Calot's triangle, prior to any dissection; (ii) after partial dissection of Calot's triangle; (iii) after complete dissection of Calot's triangle, according to the "Critical View of Safety" method.