Bas Keizers, Marcus C. M. Stroet, Meedie Ali, Sam Floru, Jelena Saliën, Laura Mezzanotte, Edward J. Delikatny, Summer L. Gibbs, Stefano Giuliani, Sylvain Gioux, Hans Ingelberts, Schelto Kruijff, Vasilis Ntziachristos, Ethan P. M. LaRochelle, Stephan Rogalla, Eben L. Rosenthal, Kimberley S. Samkoe, Kenneth M. Tichauer, Alexander L. Vahrmeijer, Max J. H. Witjes, Floris J. Voskuil, Dimitris Gorpas, Sophie Hernot, P. J. van der Zaag
Over the last three decades, fluorescence molecular imaging (FMI) in the field of biomedical optics has seen significant advancements, solidifying its role as a fundamental imaging modality capable of revealing anatomical, functional, cellular, and molecular information in living subjects and/or tissue samples. The relatively straightforward and cost-effective technology, the minimal infrastructure requirements and the absence of ionizing radiation exposure have contributed to the widespread adoption of optical fluorescence imaging. Furthermore, the availability of ready-to-use contrast agents and a variety of molecular reporters, along with the compatibility with microscopic and flow cytometry methods, has promoted utilization across numerous scientific disciplines. Hence, fluorescence imaging has become a powerful research tool for visualizing protein expression, investigating molecular interactions, tracking cells, and monitoring disease progression in a non- or minimally invasive manner 1 , 2 , 3 , 4 , 5 . In a clinical setting, fluorescence imaging is particularly valuable in the context of interventional guidance 5 , 6 , 7 , 8 . Given its high temporal resolution and sensitivity, fluorescence imaging can support real-time clinical decision-making. The near-infrared (NIR) fluorescent dye Indocyanine Green, for instance, is widely used for assessing tissue perfusion and detecting sentinel lymph nodes 9 , 10 , 11 , whereas fluorescent 5-aminolevulinic acid metabolites can aid neurosurgeons in achieving maximal safe resections of gliomas 12 , 13 . Notably, the first FDA-approved molecular contrast agents, designed to highlight or respond to specific biomarkers, have recently emerged. These include CYTALUX® (pafolacianine), a folate receptor binding fluorescent imaging agent enabling surgeons to visualize ovarian and lung cancer lesions during surgery 14 , and LUMISIGHT™ (pegulicianine), a cathepsin and matrix metalloprotease activatable agent used to detect residual cancer during lumpectomy procedures 15 . A growing number of novel fluorescent molecular agents (also known as imaging tracers) are currently under preclinical development and clinical translation for diverse applications 16 , 17 , 18 .