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As the major pipeline for transporting oxygen and nutrients to living tissues, well‐ordered and functional vasculature is vital to maintain the function of organisms. The cerebrovascular disorders induced by acute or chronic diseases, including traumatic brain injury (TBI), stroke, and brain tumors, could cause vascular cognitive impairment and even mortality. Due to the complication of these cerebrovascular diseases, early diagnosis and monitoring their pathological processes in real time in animal models could enlighten us with insights into early prevention and effective treatment. Over the last decade, the NIR‐II fluorescence imaging technology has been well developed in both nanofluorophores and imaging systems. For cerebrovascular disorders, the collaborative use of wide‐field imaging setup with NIR‐II nanoprobes enable arteriovenous staging, and calculation of blood flow velocity to distinguish ischemic area in TBI and stroke. The changes in molecular and cellular levels of TBI provide the guidance on the design of targeted and activatable NIR‐II nanoprobes for evaluating and monitoring the microenvironment variations. For the brain tumors, both targeted strategy and focus ultrasound sonication are efficient approaches for overcoming the blood‐brain‐barrier and brain‐tumor‐barrier for delivery of nanoprobes. Therefore, NIR‐II fluorescence imaging‐guided surgical navigation of brain tumors and resected lesions biopsy intraoperatively ensure the accuracy of surgery based on the precise definition of tumor margins. This review summarizes the recent advances in NIR‐II fluorescence imaging technology, which is mainly inclusive of well‐developed NIR‐II nanofluorophores and their applications in cerebrovascular diseases with address of its challenges and great potential in these aspects. [ABSTRACT FROM AUTHOR]

Anti-Stokes luminescence (ASL) based on lanthanide nanocrystals holds immense promise for in vivo optical imaging and bio-detection, which benefits from filtered autofluorescence. However, the current longest emission and excitation wavelengths of lanthanide ASL system were shorter than 1200 nm and 1532 nm, respectively, which limited tissue penetration depth and caused low signal-to-noise ratio (SNR) of in vivo imaging due to tissue scattering and water absorption. In this work, we extended the excitation wavelength to 1710 nm with the second near-infrared (NIR-II, 1000-1700 nm) emission up to 1650 nm through a novel ASL nanocrystal LiYF4:10%Tm@LiYF4:70%Er@LiYF4. Compared with 1532 nm excited ASL nanoprobes, the 1710 nm excited nanocrystals could improve in vivo imaging SNR by 12.72 folds. Based on this excellent imaging performance of the proposed ASL nanoprobes, three-channel in vivo dynamic multiplexed imaging was achieved, which quantitatively revealed metabolic rates of intestinal dynamics and liver enrichment under anesthetized and awake states. This innovative ASL nanoprobes and dynamic multiplexed imaging technology would be conducive to optimizing dosing regimen and treatment plans across various physiological conditions., (© 2024 Wiley‐VCH GmbH.)

High-resolution in vivo optical multiplexing in second near-infrared window (NIR-II, 1000-1700 nm) is vital to biomedical research. Presently, limited by bio-tissue scattering, only luminescent probes located at NIR-IIb (1500-1700 nm) window can provide high-resolution in vivo multiplexed imaging. However, the number of available luminescent probes in this narrow NIR-IIb region is limited, which hampers the available multiplexed channels of in vivo imaging. To overcome the above challenges, through theoretical simulation we expanded the conventional NIR-IIb window to NIR-II long-wavelength (NIR-II-L, 1500-1900 nm) window on the basis of photon-scattering and water-absorption. We developed a series of novel lanthanide luminescent nanoprobes with emission wavelengths from 1852 nm to 2842 nm. NIR-II-L nanoprobes enabled high-resolution in vivo dynamic multiplexed imaging on blood vessels and intestines, and provided multi-channels imaging on lymph tubes, tumors and intestines. The proposed NIR-II-L probes without mutual interference are powerful tools for high-contrast in vivo multiplexed detection, which holds promise for revealing physiological process in living body., (© 2023 Wiley-VCH GmbH.)