Optical imaging using near-infrared fluorescence
(NIRF) light has recently emerged as a promising technique
to visualize cancer cells during surgery.5–9 The advantages
of NIRF light (700–900 nm) include high tissue penetration
up to several centimeters deep, low autofluorescence
providing a sufficient signal to noise ratio, the current
availability of NIRF probes and labels for conjugation to
target tumor-specific molecules, and the insensitivity of
human eyes to near-infrared wavelengths providing no
interference with the surgical field.6 Nonetheless, only a
small number of fixed-geometry or handheld fluorescence
imaging systems have been developed with surgical
oncology in mind