Fluorescence Laparoscopy Combined With Catheter Guidance

Fluorescence Laparoscopy Combined with Catheter Guidance: The "GPS" System in Anatomical Liver Resection

The core of anatomical liver resection lies in precisely identifying and managing the vasculature of the target liver segment. Traditional laparoscopic surgery relies on the surgeon's spatial cognition and intraoperative ultrasound, while the integration of fluorescence laparoscopy​ and intraoperative catheter guidance​ functions as a real-time surgical "GPS." This system enables three-dimensional, dynamic, and color-coded visualization​ of segmental boundaries and vascular pathways. Using left lateral segmentectomy as a paradigm, this article details the application of this advanced navigation system.

I. Core Components of the Navigation System

Fluorescence Imaging Platform: An indocyanine green (ICG) fluorescence laparoscopic system.

Catheter Guidance Kit: Includes a microcatheter, guidewire, and a three-way stopcock connectable to an injection syringe.

Tracers:

ICG: For vascular and biliary tree imaging.

Methylene Blue: For biliary-specific imaging.

II. "Dual-Catheter, Dual-Fluorescence" Navigation: A Stepwise Protocol

Stage 1: Portal Venous Territory Demarcation ("Positive Staining")

Systemic ICG Administration: Preoperatively, intravenous ICG (0.25 mg/kg) provides a baseline fluorescence of the entire liver parenchyma.

Portal Vein Access: During hilar dissection, the left portal vein is exposed. Under fluorescence guidance, a fine needle punctures the umbilical portion of the left portal vein.

Selective Catheterization: A microcatheter is super-selectively advanced into the left lateral portal branch​ supplying segments S2/S3.

Positive Staining: Injection of 1-2 mL of high-concentration ICG (2.5 mg/mL) via the catheter results in intense fluorescence of S2/S3 segments. This creates a stark visual contrast ("positive stain") against the adjacent S4 segment (supplied by the left medial branch), precisely the portal venous watershed.

Stage 2: Hepatic Venous Drainage & Biliary Mapping ("Negative Staining" & "Cholangiography")

Catheter Occlusion: The microcatheter in the left lateral branch is temporarily occluded proximally.

Negative Staining: A second intravenous bolus of ICG is administered. Fluorescent blood perfuses all non-occludedsegments, while the occluded S2/S3 segments become non-fluorescent ("negative stain"), further refining the segmental boundary.

Biliary Imaging: Prior to pedicle transection, diluted methylene blue is injected via the same portal vein catheter or a separate cholecystic duct catheter. Within minutes, the biliary radicles within S2/S3 are stained blue, visible under white light, allowing precise identification of ducts for division.

Stage 3: GPS-Guided Precision Dissection

The surgeon proceeds with parenchymal transection (e.g., using an ultrasonic dissector) strictly along the fluorescent/chromatic boundary, achieving subsegmental precision.

Methylene blue-stained ducts or brightly fluorescent vessels are selectively managed (clipped/sutured) under direct vision-"see what you treat."

Tributaries of the left hepatic vein are clearly visualized under fluorescence, facilitating safe skeletonization and division.

III. Clinical Value & Illustrative Case

Case Report:

Patient: 35-year-old female with a borderline tumor in segment S3, abutting the S2/S3 intersegmental plane.

Procedure: Utilizing the described dual-catheter, dual-fluorescence navigation, a laparoscopic S3 segmentectomy​ was successfully performed.

Outcome: Precise preservation of S2 segment. Resection volume was only 8% of total liver volume. Postoperative course was uneventful.

Clinical Value:

Enhanced Radicality: For malignancies, ensures an adequate oncological margin.

Maximized Parenchymal Preservation: Crucial for patients with cirrhosis or limited functional reserve.

Reduced Complications: Targeted management of vasculobiliary structures minimizes bleeding and bile leak rates.

Accelerated Learning Curve: Provides objective, real-time anatomical guidance, aiding surgical training and standardization.

Conclusion

The fusion of fluorescence laparoscopy and catheter guidance transforms liver segmental anatomy from a domain of "empirical estimation"​ to one of "visual science."​ It epitomizes the future of precision hepatic surgery-where the procedure evolves beyond a display of technical skill into a predictable, controllable, and image-guided anatomical exercise. This paradigm shift promises safer, more precise, and parenchyma-sparing resections.