Laparoscopic cholecystectomy is the gold standard treatment for gallbladder diseases such as symptomatic gallstones, cholecystitis, and biliary dyskinesia. Despite being a common and minimally invasive surgery, one of its most critical challenges is the risk of bile duct injury. Misidentification of biliary anatomy can lead to severe complications, including bile leakage, strictures, or even life-threatening consequences. To overcome this challenge, surgeons have adopted advanced imaging techniques. Among them, Indocyanine Green (ICG) fluorescence cholangiography has emerged as a groundbreaking innovation, improving intraoperative visualization and safety.

What is Indocyanine Green (ICG)?

Indocyanine Green is a water-soluble, fluorescent dye that binds to plasma proteins and is exclusively excreted into bile by the liver. When exposed to near-infrared (NIR) light, ICG emits fluorescence, which can be captured using special laparoscopic cameras. This fluorescence highlights the biliary tree, including the cystic duct, common bile duct, and common hepatic duct, allowing the surgeon to identify critical anatomy in real time without the need for traditional contrast-based intraoperative cholangiography.

The Principle Behind ICG Cholecystectomy

During laparoscopic cholecystectomy, ICG is injected intravenously—usually 30 to 60 minutes before surgery. Once the dye is excreted into the bile, the surgeon activates the NIR light mode on the laparoscopic system. This makes the bile ducts glow fluorescent green, clearly demarcating their course against the surrounding tissues.

This technique allows visualization of:

Cystic duct

Common bile duct

Common hepatic duct

Gallbladder anatomy

Such enhanced imaging supports the Critical View of Safety (CVS) approach, which is the standard guideline for safely identifying structures before division.

Advantages of ICG Fluorescence in Cholecystectomy

Improved Identification of Anatomy

Provides clear, real-time mapping of biliary structures.

Reduces the risk of misidentifying the common bile duct as the cystic duct.

Reduced Risk of Bile Duct Injury

One of the most feared complications of cholecystectomy is major bile duct injury. ICG fluorescence significantly decreases this risk.

Non-Radiation Technique

Unlike conventional intraoperative cholangiography, ICG fluorescence does not expose the patient or surgical team to radiation.

Faster and More Convenient

Fluorescence imaging can be performed instantly without the need for C-arm fluoroscopy, contrast injection into ducts, or additional operative steps.

Cost-Effective in the Long Run

Although ICG-compatible equipment requires investment, it reduces complications, re-operations, and long-term morbidity, making it cost-effective.

Utility in Difficult Cases

In patients with acute cholecystitis, obesity, or distorted anatomy due to adhesions, ICG helps delineate critical structures.

Limitations of ICG Cholecystectomy

While the technique is highly promising, it does have certain limitations:

Limited Tissue Penetration: ICG fluorescence penetrates only up to 5–10 mm, making deeper ducts less visible.

Timing of Injection: Incorrect timing of ICG administration can lead to suboptimal visualization.

Equipment Requirement: Special NIR-capable laparoscopic systems are needed, which may not be available in all centers.

Obesity and Inflammation: In some patients with severe fat deposition or advanced inflammation, visualization may still be challenging.

Clinical Applications Beyond Cholecystectomy

ICG is not limited to gallbladder surgery. It is increasingly used in various surgical specialties, such as:

Liver surgery: To assess perfusion and identify hepatic segments.

Colorectal surgery: To evaluate bowel perfusion before anastomosis.

Urology: To visualize urinary tract structures.

Plastic and reconstructive surgery: For assessing flap viability.

This wide applicability underscores its value as a versatile surgical tool.

Evidence Supporting ICG Fluorescence

Numerous clinical studies have demonstrated that ICG fluorescence cholangiography improves safety and accuracy in laparoscopic cholecystectomy. Reported findings include:

Clear visualization of the cystic duct-common bile duct junction in more than 90% of cases.

Significant reduction in intraoperative complications and conversion to open surgery.

Better outcomes in difficult gallbladder cases, such as acute or chronic cholecystitis.

Professional surgical societies are increasingly recognizing ICG fluorescence as a valuable adjunct to standard laparoscopic techniques.

The Future of ICG in Surgery

The integration of artificial intelligence (AI) and advanced imaging software with ICG fluorescence promises even more precise mapping of biliary anatomy. Future developments may include real-time, computer-assisted guidance that overlays anatomical structures on the surgeon’s screen, further reducing human error. With wider adoption and falling costs of NIR imaging systems, ICG-guided cholecystectomy is expected to become the new global standard.

Conclusion

Indocyanine Green (ICG) fluorescence cholangiography is a transformative innovation in laparoscopic cholecystectomy. By enhancing visualization of the biliary anatomy, it minimizes the risk of bile duct injuries, shortens operative time, and increases overall surgical safety. While it requires specialized equipment and proper timing for optimal results, its benefits far outweigh the limitations.

As technology advances, ICG cholecystectomy is set to redefine the standards of minimally invasive gallbladder surgery, ensuring safer outcomes for patients worldwide.