Simultaneous multipurpose fluorescence imaging with IRDye® 800BK during laparoscopic surgery

IRDye® 800BK is a fluorophore, currently undergoing clinical translation, which has both biliary and renal clearance. To date, there is no description of a fluorophore, which can be simultaneously used for non-invasive, near-infrared fluorescence-based (NIRF) visualization of different structures and perfusion evaluation. The purpose of this study was to evaluate IRDye® 800BK for the simultaneous assessment of bowel perfusion, lymphography, ureter and bile duct delineation.

Six pigs received a 0.15 mg/kg dye as a single bolus intravenous injection (IV). With the FLER (fluorescence-based enhanced reality) software, fluorescence intensity (FI) of 5 regions of interest (ROI) in an ischemic bowel loop was measured along with the time to reach the FI peak, and capillary lactate was measured from the same ROI, followed by the assessment of the ureters and bile ducts for a maximal duration of 180 min after dye administration. In 3 animals, the procedure was initiated via gastroscopic injection of a 0.6 mg (1 mg/mL) dye in the gastric submucosa followed by lymphography in a NIRF setting.

Excellent visualization of the ureters and bowel perfusion was obtained under NIRF imaging. Additionally, the bile duct and gastric lymph ducts and nodes were visualized. A positive correlation was found between the time to peak FI in the ischemic bowel loop and the corresponding capillary lactate levels (rho 0.59, p < 0.001).

In this study, we successfully demonstrated the simultaneous multipurpose IRDye® 800BK applicability during laparoscopic surgery. This fluorophore has the potential to become a powerful and versatile image-guided surgery tool.