Second near-infrared (NIR-II) imaging: a novel diagnostic technique for brain diseases
Na Xie, Ya Hou, Shaohui Wang, Xiaopeng Ai, Jinrong Bai, Xianrong Lai, Yi Zhang, Xianli Meng, Xiaobo Wang
Abstract
Abstract Imaging in the second near-infrared II (NIR-II) window, a kind of biomedical imaging technology with characteristics of high sensitivity, high resolution, and real-time imaging, is commonly used in the diagnosis of brain diseases. Compared with the conventional visible light (400–750 nm) and NIR-I (750–900 nm) imaging, the NIR-II has a longer wavelength of 1000–1700 nm. Notably, the superiorities of NIR-II can minimize the light scattering and autofluorescence of biological tissue with the depth of brain tissue penetration up to 7.4 mm. Herein, we summarized the main principles of NIR-II in animal models of traumatic brain injury, cerebrovascular visualization, brain tumor, inflammation, and stroke. Simultaneously, we encapsulated the in vivo process of NIR-II probes and their in vivo and in vitro toxic effects. We further dissected its limitations and following optimization measures.