Intraoperative ureter identification with a novel fluorescent catheter

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.

In Vivo Imaging Evaluation of Fluorescence Intensity at Tail Emission of Near-Infrared-I (NIR-I) Fluorophores in a Porcine Model

“…As previously described, ICG tail emission was unintentionality found in vitro [ 17 ]. It was later on studied by Starosolski et al in an ICG perfusion study in mice models [ 12 ].…”

“…These pivotal reports have provided a plausible foundation for our current experiment, which detects the ICG MFI at the tail emission (1200 nm) in a large animal model using a recent commercially available NIR-II imaging system. Interestingly, the previously published NIR-II off-peak emission of ICG has even been detectable up to 1575 nm [ 17 ].…”

“…Additionally, the photostability after 1 h irradiation at 760 nm only has a minor decrease in fluorescence intensity. To date, NICE has been validated in multiple preclinical models [ 15 , 16 , 17 , 18 , 19 ].…”

Intraoperative Guidance Using Hyperspectral Imaging: A Review for Surgeons

“…Again, this process is currently strictly dependent on the surgeon's visual capabilities and anatomical knowledge and currently there are no universally accepted methods to recognize noble anatomical structures intraoperatively. However, several experimental methods using optical imaging modalities, but still requiring an injection of exogenous contrast agents [61][62][63] or the use of fluorescent devices [64][65][66], have been put forward to highlight key anatomical structures within human or experimental models.…”

A Novel Technique Using Fluorescent Ureteral Catheter and Flexible Ureteroscope for Safe Laparoscopic Fenestration of Lymphocele after Kidney Transplantation

“…The near-infrared ray catheter (NIRC™) fluorescent ureteral catheter (Nippon Covidien, Ltd., Tokyo, Japan) is a novel catheter containing fluorescent material that can be visualized under near-infrared irradiation. It provides the necessary anatomical information for avoiding ureteral damage and ensuring safer surgery [3][4][5].…”