title: Near-infrared fluorescence laparoscopy of the cystic duct and cystic artery: first experience with two new preclinical dyes in a pig model.
abstract: Imaging techniques that enhance visualisation of the anatomy may help prevent bile duct injury. Near-Infrared Fluorescence Imaging is such a technique. Previous experiments with ICG have shown that illumination of the extra-hepatic bile ducts is feasible. Yet, there is room for improvement in the visualisation of the target as compared to the background. Experiments with IRDye®800CW show promising results. However, this dye is too expensive for routine clinical use. The aim of this study is to test the first applicability of two newly developed preclinical dyes regarding intraoperative imaging of the cystic duct and cystic artery, compared with IRDye®800CW.
  
  
  
  Laparoscopic cholecystectomy was performed in three pigs, using a laparoscopic fluorescence imaging system. Each pig received 6 mg of one of the fluorescent dyes (1 mg/mL; IRDye®800CW, IRDye®800BK or IRDye®800NOS) by intravenous injection. Intraoperative recognition of the biliary system and cystic artery was registered at set time points. All procedures were digitally recorded, and the target to background ratio (TBR) was determined to assess the fluorescence signal.
  
  
  
  With all three fluorescent dyes, the cystic artery was directly visualised. For the visualisation of the cystic duct, 15, 34 and 30 min were needed using IRDye®800BK, IRDye®800NOS and IRDye®800CW, respectively. The maximum TBR of the cystic duct was the highest with IRDye®800NOS (4.20) after 36 min, compared to 2.45 for IRDye®800BK and 2.15 for IRDye®800CW, both after 45 min. There were no adverse events.
  
  
  
  IRDye®800BK and IRDye®800NOS seem to be good alternatives for IRDye®800CW for the visualisation of the cystic duct and cystic artery in pigs.
authors.affiliation: Department of Surgery, Maastricht University Medical Center, Post Box 5800, 6202 AZ, Maastricht, The Netherlands. j.vandenbos@maastrichtuniversity.nl.|NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands. j.vandenbos@maastrichtuniversity.nl.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: van den Bos
authors.affiliation: Department of Surgery, Maastricht University Medical Center, Post Box 5800, 6202 AZ, Maastricht, The Netherlands.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Al-Taher
authors.affiliation: Department of Surgery, Maastricht University Medical Center, Post Box 5800, 6202 AZ, Maastricht, The Netherlands.
authors.forename: Shu Gi
authors.initials: SG
authors.lastname: Hsien
authors.affiliation: Department of Surgery, Maastricht University Medical Center, Post Box 5800, 6202 AZ, Maastricht, The Netherlands.|NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands.
authors.forename: Nicole D
authors.initials: ND
authors.lastname: Bouvy
authors.affiliation: Department of Surgery, Maastricht University Medical Center, Post Box 5800, 6202 AZ, Maastricht, The Netherlands.|NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands.
authors.forename: Laurents P S
authors.initials: LPS
authors.lastname: Stassen
mesh_terms: D000818:Animals; D001158:Arteries / Q000000981:diagnostic imaging* / Q000601:surgery; D017081:Cholecystectomy, Laparoscopic; D003549:Cystic Duct / Q000000981:diagnostic imaging* / Q000601:surgery; D005456:Fluorescent Dyes; D007211:Indoles; D023421:Models, Animal; D061848:Optical Imaging; D013552:Swine
chemical_list: D005456:Fluorescent Dyes; C427728:IRDye800; D007211:Indoles
keywords: Biliary anatomy; Fluorescent cholangiography; Fluorescent dyes; Laparoscopic cholecystectomy; Near-infrared fluorescence imaging