Optimal timing for preoperative indocyanine green administration to enhance fluorescent cholangiography during laparoscopic cholecystectomy: a prospective study

Background: Safe and accurate visualization of biliary anatomy is essential during laparoscopic cholecystectomy. Indocyanine green (ICG) fluorescence cholangiography has emerged as a valuable tool to delineate critical structures and reduce the risk of bile duct injury. While earlier studies recommended ICG administration 8–24 hours prior to surgery, recent evidence suggests that shorter intervals may be equally effective. This prospective study compared the efficacy of ICG fluorescence cholangiography administered 4 hours versus 8 hours before laparoscopic cholecystectomy, focusing on the clarity of biliary visualization, operative outcomes and patient recovery. Methods: Sixty patients undergoing elective laparoscopic cholecystectomy were randomized into two groups: Group A (ICG administered 4 hours preoperatively) and Group B (8 hours). A standardized scoring system assessed visualization of the cystic duct and common bile duct. Operative duration, complications and recovery were secondary outcomes. Results: Both groups showed high rates of optimal biliary tract visualization (≥4/5 score): 90% in Group A and 93.3% in Group B (p=0.64). Mean operative times were similar (48.3±8.5 vs. 46.9±7.9 minutes; p=0.42). No major bile duct injuries occurred. Postoperative complication rates and hospital stays were also comparable. Conclusions: ICG administration as early as 4 hours before surgery provides biliary visualization equivalent to the conventional 8-hour interval. This shorter window may enhance scheduling flexibility without compromising safety or image quality. Further multicentre studies are recommended to validate these findings.