Fluorescence Ureteral Visualization in Human Laparoscopic Colorectal Surgery Using Methylene Blue

Area of Science:

• Surgical Innovation
• Medical Imaging
• Urology

Background:

• Ureteral injury is a rare but serious complication in laparoscopic surgery.
• Near-infrared fluorescence (NIRF) imaging with methylene blue (MB) offers potential for improved intraoperative ureteral visualization.
• Assessing the feasibility of NIRF imaging for ureter identification during laparoscopic colorectal procedures.

Purpose of the Study:

• To evaluate the feasibility of using NIRF imaging with MB for intraoperative ureter visualization.
• To compare the effectiveness of MB-enhanced fluorescence imaging against conventional laparoscopic views.
• To determine the safety and utility of MB for ureter identification in laparoscopic colorectal surgery.

Main Methods:

• Prospective study involving patients undergoing laparoscopic colorectal surgery.
• Intravenous administration of methylene blue (MB) preoperatively.
• Ureter visualization using a laparoscope with conventional and NIRF imaging capabilities.

Main Results:

• MB administration was safe, with no adverse effects noted in ten patients.
• Successful ureter detection using NIRF imaging occurred in five patients.
• Optimal contrast was observed at MB doses of 0.75-1.0 mg/kg, but fluorescence was only visible after conventional detection.

Conclusions:

• Ureteral fluorescence imaging with MB is safe and feasible.
• The current technique does not provide a practical advantage over conventional laparoscopic imaging for ureter identification.
• Further research is needed to optimize MB dosage, explore alternative dyes, or enhance imaging systems for clinical benefit.