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

Abstract

Over the last decade fluorescence-guided surgery has been primarily focused on the NIR-I window. However, the NIR-I window has constraints, such as limited penetration and scattering. Consequently, exploring the performance of NIR-I dyes at longer wavelengths (i.e., the NIR-II window) is crucial to expanding its application. Two fluorophores were used in three pigs to identify the mean fluorescence intensity (MFI) using two commercially available NIR-I and NIR-II cameras. The near-infrared coating of equipment (NICE) was used to identify endoluminal surgical catheters and indocyanine green (ICG) for common bile duct (CBD) characterization. The NIR-II window evaluation showed an MFI of 0.4 arbitrary units (a.u.) ± 0.106 a.u. in small bowel NICE-coated catheters and an MFI of 0.09 a.u. ± 0.039 a.u. in gastric ones. In CBD characterization, the ICG MFI was 0.12 a.u. ± 0.027 a.u., 0.18 a.u. ± 0.100 a.u., and 0.22 a.u. ± 0.041 a.u. at 5, 35, and 65 min, respectively. This in vivo imaging evaluation of NIR-I dyes confirms its application in the NIR-II domain. To the best of our knowledge, this is the first study assessing the MIF of NICE in the NIR-II window using a commercially available system. Further comparative trials are necessary to determine the superiority of NIR-II imaging systems.

Short-wave infrared fluorescence imaging of near-infrared dyes with robust end-tail emission using a small-animal imaging device

“…However, the primary components of the device, being the camera and excitation light sources, appear suitable for clinical scenarios because of their sufficiently compact size and achievable cooling requirements. Other SWIR fluorescence imaging systems have been reported in the literature, for example commercial small-animal laboratory devices ( 19 , 20 ) and academic research device ( 2 , 21 ). In contrast to many devices described in the literature, the SWIR imaging system does not use high-powered laser excitation or a deep-cooled camera, rather LED illumination, potentially easing device development and clinical translation.…”

Recent progress of second near-infrared (NIR-II) fluorescence microscopy in bioimaging

“…Although small-molecule fluorophores have made great strides in NIR-II fluorescence imaging, most fluorophores are only used in small animals, and are still a long way from clinical application. Fortunately, scientists ( Han et al, 2022 ; Kasprzyk et al, 2022 ; Rodriguez-Luna et al, 2022 ) have successfully applied some small molecular fluorophores to large animals (rabbits and monkeys) and humans to accelerate their clinical translation. However, ICG has low photostability and its fluorescence is easily quenched ( Potharazu and Gangemi, 2022 ).…”

In Vitro Antibody Quantification with Hyperspectral Imaging in a Large Field of View for Clinical Applications

“…HSI is a non-invasive, contrast-free tool recently applied in several medical and basic research fields [ 5 , 6 ], like other new emerging technologies [ 7 , 8 ]. Several innovative approaches are under investigation that exploit the capability of HSI to “see beyond” the visible range, such as intraoperative tissue recognition [ 9 ], therapy guidance, and monitoring [ 10 , 11 , 12 , 13 , 14 ].…”