McWade MA, et al. - In this study, an overlay tissue imaging system (OTIS) was designed that detects tissue near infrared autofluorescence (NIRAF) and back-projects the collected signal as a visible image directly onto the surgical field of view instead of a display monitor. Researchers tested its ability for improving parathyroid visualization. They tested OTIS ex vivo with parathyroid, thyroid, and lymph node specimens and identified it as 100% accurate. They recommend additional device optimization for eventual clinical use despite OTIS holds novel potential for enhancing label-free parathyroid visualization directly within the surgical field of view.