Clinical research progress on the fluorescence imaging in the second near-infrared window

The near-infrared fluorescence imaging is a vital technology that enables the image-guided surgery. In recent years, the maturation of the optical bioimaging theory in the second near-infrared window (NIR-II, 900-1 700 nm) has led to the emergence of NIR-II fluorescence imaging as a significant research area in the imaging-guided surgery. This paper provides a succinct overview on the current development state of NIR-II fluorescence probes and imaging systems based on the NIR-II optical bioimaging theory. Furthermore, it reviews the studies conducted on the NIR-II fluores- cence imaging in the small animal and clinical surgery, and discusses the potential and challenges of this technology in the clinical surgery, including the difficulties that need to be addressed in the future clinical translation.