Exploiting molecular probes to perform near‐infrared fluorescence‐guided surgery

Abstract

Near-infrared (NIR) fluorescence imaging can provide real-time navigation for surgeons to discriminate boundaries between lesions and healthy tissue, which serves as a promising tool to enhance precise diagnosis and accurate excision during surgery. Molecular probes with NIR fluorescence can visualize diseased tissue in deep penetration with improved signal-to-noise ratio, which considerably encourages the active participation of NIR fluorescence-guided surgery in the operating room. Although a great quantity of fluorescent probes has been employed in clinical trials, the U.S. Food and Drug Administration only approves an extremely narrow number of contrast agents for clinical use so far. Currently, there remain two significant problems to be addressed in surgical resection: accurate identification of diseased tissue and the preservation of adjacent vital structures. Here, molecular probes with NIR fluorescence are systematically reviewed to offer possible solutions to these two problems. Targeting strategies of fluorescent probes are introduced, where the strengths and weaknesses of each strategy are presented. Advances in fluorescent probes for the imaging of vital structures, such as nerve and ureter, are also summarized in this review. It is convinced that NIR fluorescence-guided surgery has the potential to improve current surgical resection and ameliorate the postoperative outcomes of diverse diseases.

A Glutathione Activatable Photosensitizer for Combined Photodynamic and Gas Therapy under Red Light Irradiation

“…This is a favorable result for the combined therapeutics because light in the therapeutic window (650-900 nm) can penetrate into tissue deeply with less photodamage to healthy tissues. [34,35]…”

Versatile Types of Inorganic/Organic NIR-IIa/IIb Fluorophores: From Strategic Design toward Molecular Imaging and Theranostics

“…In 2009, Smith et al proposed the second “transparent window” with a longer wavelength from 1000 to 1700 nm, which is also called the near-infrared II (NIR-II) window . Specifically, the NIR-II window can be divided into two subwindows named NIR-IIa (1300–1400 nm) and NIR-IIb (1500–1700 nm) since a water overtone absorption peak is located at ∼1450 nm (Figure b). , According to the Mie theory and Monte Carlo simulation of scattering, the photon scattering scales are described as μs′ ≈ λ – w , where w ranges from 0.2 to 4 in different tissues (Figure c). ,− Therefore, fluorescence imaging in the NIR-IIa/IIb windows with longer wavelength can achieve lower photon scattering. Moreover, the autofluorescence will be diminished to a near-zero level in the NIR-IIb window (Figure d).…”

Recent Progresses in NIR-I/II Fluorescence Imaging for Surgical Navigation

“…The applications of this innovative NIR-II region in biomedical imaging have significantly improved the temporal and spatial resolution and penetration depth because of negligible tissue absorption, weakened scattering, and minimum autofluorescence ( Ding et al, 2018b ; Wan et al, 2019 ; Dai et al, 2021 ). As a rapidly developing technology, near-infrared fluorescence-guided surgery helps surgeons in determining the tumor margins of some cancer types and the lesions of other common diseases with great accuracy ( Scheme 1 ) ( Li et al, 2019 ; Zhu et al, 2019 ; Wu and Zhang, 2020 ; Xu et al, 2020 ; Yang et al, 2021 ).…”