Non-invasive Detection of Retained Surgical Items Using Near-Infrared Fluorescence

This proposed research focuses on the preliminary investigation for developing a novel detection method for retained surgical items (RSIs), specifically surgical sponges. Several methods are currently available for the avoidance and detection of RSIs; however, they remain a significant problem. The proposed research utilizes the transparent near-infrared region (800 nm) which is devoid of fluorescence and absorption by the human body. This wavelength has significant penetration depth and can be effectively used to detect objects intraoperatively. In our preliminary studies, we have shown that the non-covalently linked NIR dye ICG enables quick and accurate identification of surgical sponges even in highly scattering media analogous to the surgical field. Additionally, the systems needed for the fluorescence imaging in this wavelength are both cheap and robust. We now seek to improve upon the initial method we have developed. We will do this in two ways: firstly by testing other classes of NIR fluorophores in order to optimize the stability and optical properties of the imaging agents and secondly by covalently linking a fluorophore to the polymer of the surgical sponges as a proof of concept. While we will only be testing surgical sponges, this method of tagging surgical materials can be applied to many other materials including plastics and other types of bandaging. This seed grant will be crucial for developing the data required for extramural funding toward developing a procedure for covalently labeling surgical sponges using our synthesized NIR dye and further clinical implementation of this technique.