In vivo multi-wavelength optical-resolution photoacoustic microscopy with stimulated Raman scattering fiber-laser source

In this paper we demonstrate a multi-wavelength optical resolution photoacoustic microscopy system for both phantom and in vivo imaging. Using a 1ns pulse width, 40-kHz repetition-rate ytterbium-doped fiber laser and a 3m single-mode polarization maintaining fiber, we produced numerous Raman-shifted wavelength peaks at with pulse energies between 100 and 400nJ per peak. Peak wavelengths were selected by using 10-nm linewidth bandpass filters. The capabilities of this system is shown by creating C-scan photoacoustic images of carbon fiber networks, 200μm dye-filled tubes, and Swiss Webster mouse ears at several wavelengths. Functional imaging potential was confirmed by assessing tubes filled with varying concentrations of two different dyes.