CBD Wall-Thickness Adjusted ICG Microdosing for Fluorescence Cholangiography in Moderate-to-Severe Acute Cholecystitis: A Single-Center Prospective Study

Peking Union Medical College Hospital21 enrolled

Overview

This is a single-center prospective study designed to develop and validate an individualized, low-dose indocyanine green (ICG) protocol for near-infrared fluorescence cholangiography during emergency laparoscopic cholecystectomy in patients with moderate to severe acute cholecystitis. The main problem we aim to solve is that inflammation in the bile duct wall often makes standard ICG doses ineffective for clear visualization. We will use pre-operative MRI to measure the thickness of the common bile duct (CBD) wall, then calculate a personalized ICG dose using a simple formula. We will first test and refine this formula in a small group of patients, then verify its effectiveness in a second group. The goal is to achieve clear, high-contrast imaging of the bile ducts, which helps surgeons operate more safely and accurately. All patients will receive a low, personalized dose of ICG given by vein 1 hour before surgery. We will evaluate how well the bile ducts show up on the fluorescence images, as well as safety and effectiveness outcomes. This study will provide a practical, patient-tailored solution for improving bile duct visualization in emergency gallbladder surgery.

Study Type

INTERVENTIONAL

Allocation

Purpose

DIAGNOSTIC

Masking

NONE

Enrollment

Conditions

Acute Cholecystitis

Interventions

Indocyanine Green (ICG) Fluorescence CholangiographyDRUG

Indocyanine green (ICG) is administered intravenously 1 hour before emergency laparoscopic cholecystectomy. The dose is individualized based on preoperative MRI-measured common bile duct wall thickness using the formula: 0.012 + 0.0035625 × wall thickness (mg/kg). Near-infrared fluorescence cholangiography is performed intraoperatively to visualize the biliary anatomy.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 80 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients aged ≥18 years undergoing emergency laparoscopic cholecystectomy. * Diagnosis of moderate to severe acute cholecystitis according to the 2018 Tokyo Guidelines. * Preoperative MRI available for common bile duct wall thickness measurement. * Ability to provide informed consent. Exclusion Criteria: * Known allergy or contraindication to indocyanine green (ICG). * Severe renal or hepatic dysfunction (eGFR \<30 mL/min/1.73m² or Child-Pugh class B/C cirrhosis). * Pregnancy or breastfeeding. * Previous biliary surgery or known choledocholithiasis requiring preoperative intervention. * Unstable hemodynamic status requiring conversion to open surgery before ICG administration.

Outcomes

Primary Outcomes

Subjective Biliary Tract Visualization Quality Score

Intraoperative assessment of biliary tract visualization quality using a 4-point subjective scale (1=poor, 2=fair, 3=good, 4=excellent). The score is assigned by the operating surgeon based on the clarity of the cystic duct and common bile duct fluorescence signals, with a primary endpoint of achieving a mean score of ≥3.0 across all enrolled patients.

Time frame: Intraoperatively (during emergency laparoscopic cholecystectomy)