Colorful lighting in the operating room

In recent trials, fluorescence image-guided surgery (FIGS) has proven useful in patients, resulting in superior outcomes compared to conventional procedures. To perform FIGS, a fluorescent dye or probe is injected intravenously or applied topically prior to the procedure. After a short waiting period, the areas of interest are illuminated with excitation light at specific wavelengths (colors). The energy from the excitation light is absorbed by the locally retained fluorochromes and discharged quickly, resulting in a pulse of emission light with longer wavelengths. Because of the wavelength difference between the excitation and emission light, high signal-to-background ratios are often obtained. The emitted light is either visualized directly or acquired through a charge-coupled device (CCD) camera and displayed on a monitor. Another advantage of FIGS is its real-time imaging capability. Surgeons can follow the fluorescent signal conveniently during the procedure without data acquisition delays.