Intraoperative ureter identification with a novel fluorescent catheter

Manuel Barberio,Mahdi Al-Taher,Jacques Marescaux,Eric Felli,Anila Hoskere Ashoka,Andrey Klymchenko,Michele Diana

doi:10.1038/s41598-021-84121-z

Abstract

Iatrogenic ureteral injuries (IUI) occur in 0.5–1.3% of cases during abdominal surgery. If not recognized intraoperatively, IUI increase morbidity/mortality. A universally accepted method to prevent IUI is lacking. Near-infrared fluorescent imaging (NIRF), penetrating deeper than normal light within the tissue, might be useful, therefore ureter visualization combining NIRF with special dyes (i.e. IRDye 800BK) is promising. Aim of this work is to evaluate the detection of ureters using stents coated with a novel biocompatible fluorescent material (NICE: near-infrared coating of equipment), during laparoscopy. female pigs underwent placement of NICE-coated stents (NS). NIRF was performed, and fluorescence intensity (FI) was computed. Successively, 0.15 mg/kg of IRDye 800BK was administered intravenously, and FI was computed at different timepoints. Ureter visualization using NS only was further assessed in a human cadaver. Both methods allowed in vivo ureter visualization, with equal FI. However, NS were constantly visible whereas IRDye 800BK allowed visualization exclusively during the ureteral peristaltic phases. In the human cadaver, NS provided excellent ureter visualization in its natural anatomical position. NS provided continuous ureteral visualization with similar FI as the IRDye 800BK, which exclusively allowed intermittent visualization, dependent on ureteral peristalsis. NS might prove useful to visualize ureters intraoperatively, potentially preventing IUI.

Highlights

Cumbersome retrograde injection by means of ureteral stent or cystoscopy[15,16]
The surgical procedures were performed without any complications or adverse events in every animal. Both the near-infrared coating of equipment (NICE)-coated catheter and the IRDye 800BK allowed for a satisfactory visualization of the ureters under NIR light in each pig
The NICE-coated catheter was constantly clearly visible (Fig. 2) whereas the IRDye 800BK allowed for ureter visualization exclusively during ureteral peristaltic phases (Fig. 3), which occurred with irregular frequency in the animals

Summary

Introduction

MB has a partial renal clearance and is subsequently present at high concentration within the urinary tract, following its intravenous injection This dye has inefficient optical properties (low quantum yield, poor brightness, and poor tissue penetration) and it requires modified NIRF imaging systems, most of which are not available for commercial use y et[14]. For such reasons, a number of new dyes are currently d eveloped[14], and among these dyes, the IRDye 800BK (nerindocianine sodium) has shown promising experimental results[17,18,19,20]. The efficiency of NICE-coated catheters to visualize human ureters in their natural anatomical position was assessed during a human cadaveric experiment

Methods

Results

Conclusion