Acute Cholecystitis Biliary Complications - ICG

Acute cholecystitis is one of the most common indications for emergency abdominal surgery. Early laparoscopic cholecystectomy is considered the standard treatment; however, inflammation and distorted anatomy may make identification of the biliary structures challenging, increasing the risk of bile duct injury or bile leak. These complications are associated with significant morbidity, need for additional procedures, prolonged hospitalization, and increased healthcare costs.

Indocyanine green (ICG) fluorescence cholangiography is an intraoperative imaging technique that allows real-time visualization of the extrahepatic biliary anatomy using near-infrared fluorescence. After intravenous administration, ICG is rapidly excreted into bile, enabling enhanced visualization of the biliary tree during laparoscopic surgery. Several studies in elective laparoscopic cholecystectomy have demonstrated that ICG fluorescence improves anatomical identification and may increase surgical safety. However, evidence regarding its effectiveness in the emergency setting of acute cholecystitis remains limited, and high-quality multicenter randomized controlled trials are lacking.

The ICG-ACBC Trial is designed to evaluate whether the systematic use of ICG fluorescence cholangiography during emergency laparoscopic cholecystectomy for acute cholecystitis reduces the incidence of clinically relevant biliary complications compared with standard laparoscopic cholecystectomy without fluorescence guidance.

This study is a multicenter, pragmatic, open-label randomized controlled trial. A total of 296 adult patients diagnosed with acute cholecystitis according to Tokyo Guidelines criteria and requiring urgent laparoscopic cholecystectomy will be enrolled across participating hospitals. Participants will be randomized in a 1:1 ratio to undergo surgery either with intraoperative ICG fluorescence guidance or with standard laparoscopic cholecystectomy without ICG. Randomization will be centralized and stratified by participating center.

In the intervention group, patients will receive an intravenous dose of indocyanine green prior to surgery, and near-infrared imaging will be used intraoperatively to visualize the biliary anatomy. In the control group, patients will undergo standard laparoscopic cholecystectomy following established surgical principles, including the critical view of safety.

The primary outcome is the incidence of clinically relevant biliary complications, defined as bile duct injury or clinically significant bile leak, occurring within 90 days after surgery. Secondary outcomes include other perioperative complications, conversion to open surgery, length of hospital stay, reinterventions, readmissions, surgeon-reported visualization quality, and patient-reported outcomes.

The results of this study may provide high-quality evidence on whether routine use of ICG fluorescence cholangiography improves surgical safety in emergency cholecystectomy for acute cholecystitis and may inform future clinical guidelines and surgical practice.

• ICG (Other): Emergency laparoscopic cholecystectomy performed with intraoperative indocyanine green fluorescence cholangiography to enhance visualization of the biliary anatomy.

Primary outcomes

• Incidence of Clinically Relevant Biliary Complications [Within 90 days after surgery]: Clinically relevant biliary complications defined as bile duct injury or clinically significant bile leak requiring therapeutic intervention. Bile leak will be defined according to the criteria of the International Study Group of Liver Surgery (ISGLS), and bile duct injury will be classified according to the Strasberg classification.

Secondary outcomes

• Overall Postoperative Complications [Within 90 days after surgery]: Incidence of postoperative complications including bile leak, bile duct injury, bleeding, surgical site infection, intra-abdominal abscess, visceral or vascular injury, and reintervention. Complications will be graded according to the Clavien-Dindo classification and summarized using the Comprehensive Complication Index (CCI).
• Conversion to Open Surgery [Day of the Surgery]: Rate of conversion from laparoscopic to open cholecystectomy during surgery.
• Length of Hospital Stay [Day 1 of admission]: Postoperative hospital stay measured in days from surgery to hospital discharge.
• Readmission Rate [Within 90 days after surgery]: Unplanned hospital readmission related to the surgical procedure or postoperative complications.
• Quality of Biliary Anatomy Visualization (ICG group) [Day of the Surgery]: Qualitative assessment of intraoperative visualization of biliary structures (cystic duct, common bile duct, cystic duct-CBD junction, cystic artery, and common hepatic duct) using near-infrared fluorescence imaging. Visualization quality will be graded using a Likert scale.
• Surgeon-Reported Surgical Confidence [Day of the Surgery]: Surgeon-reported perception of anatomical clarity and confidence during dissection, measured using a structured postoperative questionnaire.
• Patient-Reported Outcomes (PROMs) [30 days and 90 days after surgery]: Patient-reported health status assessed using the EQ-5D-5L questionnaire.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Age ≥ 18 years.
* Diagnosis of acute cholecystitis according to Tokyo Guidelines (TG18) criteria.
* Planned urgent/emergency laparoscopic cholecystectomy during the index admission, as determined by the treating surgical team.
* Ability to provide written informed consent prior to surgery.

Exclusion Criteria:

* Known hypersensitivity or contraindication to indocyanine green (ICG) or its excipients.
* Pregnancy or breastfeeding.
* Clinical situation preventing protocol implementation or informed consent (e.g., life-threatening emergency requiring immediate surgery without time for study procedures).
* Primary open cholecystectomy planned (i.e., not intended laparoscopic approach).
* Any condition that, in the investigator's opinion, makes participation unsafe or not feasible.