First clinical applications for the NIR-II imaging with ICG in microsurgery

Abstract

In microsurgery, it is always difficult to accurately identify the blood supply with ease, such as vascular anastomosis, digit replantation, skin avulsion reconstruction and flap transplantation. Near-infrared window I (NIR-I, 700—900 nm) imaging has many clinical applications, whereas near-infrared window II (NIR-II, 1,000–1700 nm) imaging has emerged as a highly promising novel optical imaging modality and used in a few clinical fields recently, especially its penetration distance and noninvasive characteristics coincide with the needs of microsurgery. Therefore, a portable NIR-II imaging instrument and the Food and Drug Administration (FDA) approved indocyanine green (ICG) were used to improve the operation efficiency in microsurgery of 39 patients in this study. The anastomotic vessels and the salvaged distal limbs were clearly visualized after intravenous injection of ICG. The technique enabled identification of perforator vessels and estimation of perforator areas prior to the flap obtention and made it easier to monitor the prognosis. Overall, this study highlights the use of the portable NIR- II imaging with ICG as an operative evaluation tool can enhance the safety and accuracy of microsurgery.

The Application of Bio-orthogonality for In Vivo Animal Imaging

“…NIRF imaging is one of the most used technologies for preclinical animal studies and fluorescence imaging-guided surgery (FIGS), due to its acceptable tissue penetration, low cost, and simple imaging acquisition and data analysis . The recent development of NIR-II imaging probes and methods further enhances the capacity of NIRF imaging. − Bio-orthogonal chemistry provides enormous potential for in vivo imaging with NIRF probes, since nonspecific fluorescence from the excess probe, which can be washed away, has minimal interference. In addition, the tissue penetrance of NIRF is considerably high.…”

Imaging peripheral lymphatic dysfunction in chronic conditions

“…Increasing the power of the incident excitation light or the dose of ICG may result in a stronger fluorescent signal from the tissues, but nonetheless is likely to be insufficient to non-invasively image deeper tissues ( Zhu et al, 2020 ). SWIR has been deployed clinically in intraoperative studies ( Teng et al, 2021 ; Shi et al, 2022 ; Wu et al, 2022 ) but to date, not for non-invasive clinical imaging of intact tissues.…”

Rational Design of Virus-like Particles for Nanomedicine

“…32 This infrared frequency allows deep tissue penetration, enabling ICG to be used not only for photothermal (PTT) and photodynamic (PDT) therapy, but also for near-infrared fluorescence imaging (NIR-FL) and (photoacoustic tomography) PAT imaging. 33 There are strong indications that ICG can be considered an ideal theranostic agent for cancer treatment. 34 However, due to the drawbacks of free ICG, including instability and self-aggregation in aqueous solutions, nonspecific binding to proteins leading to rapid aggregation and elimination from the body, and nontargeting capabilities, its application fails to achieve the desired therapeutic and diagnostic results.…”