Spatially multiplexed random-access Raman probe for in vivo tissue measurements

Raman spectroscopy enables label-free identification of biological tissues, but its clinical application remains limited due to low-throughput measurements. Here, we developed a spatially multiplexed random-access Raman probe that enables simultaneous spectral acquisition from arbitrarily selected locations in vivo. Parallel acquisition of up to 1718 spectra in a single exposure has been enabled by using a custom fiber bundle in combination with a spatial light modulator. In vivo measurement of a peripheral nerve in the abdominal cavity of an anesthetized canine demonstrated the feasibility of the developed system for intraoperative tissue identification within 5 s. We further performed discriminant analysis of multipoint spectra from nerve and non-nerve regions in rats, which achieved 92.5% accuracy and sensitivity for nerve discrimination. The developed system provides a basis for efficient and accurate navigation in surgery.