This is a multicenter, prospective, interventional clinical trial designed to evaluate and compare two intraoperative imaging modalities: laparoscopic ultrasound (LUS) and fluorescence cholangiography with indocyanine green (ICG), for the identification of biliary anatomy in technically challenging laparoscopic cholecystectomy. All enrolled subjects will undergo both LUS and ICG during the index procedure, following a standardized sequence, in order to allow intra-subject comparison. LUS will be performed first, followed by fluorescence cholangiography prior to Calot's triangle dissection.

The primary endpoint is the successful identification of the critical junction. Secondary endpoints include visualization of individual biliary structures, time to visualization, total operative time, intraoperative and postoperative complications.

Inclusion Criteria:

1. Age ≥ 18 years.

2. Written informed consent provided.

3. Indication for laparoscopic cholecystectomy with anticipated technical difficulty due to one or more of the following:

   • Acute cholecystitis.
   • Previous cholangitis, pancreatitis, or endoscopic retrograde cholangiopancreatography.
   • Prior upper abdominal surgery.
   • Obesity (Body Mass Index ≥ 30 kg/m²).

Exclusion Criteria:

1. Known allergy to ICG or iodine.
2. Pregnancy or breastfeeding.
3. High risk of choledocholithiasis (ESGE guidelines).
4. Thyroid disease.
5. Suspected gallbladder malignancy.
6. ASA class IV-V.
7. Chronic kidney disease stage > IIIb.
8. Planned open cholecystectomy.