High-resolution imaging in a deep turbid medium based on an ultrasound-switchable fluorescence technique

Abstract

**Please note that the full text is embargoed** ABSTRACT: The spatial resolution of fluorescence imaging techniques in deep optically turbid media such as tissues is limited by photon diffusion. To break the diffusion limit and achieve high-resolution and deep-tissue fluorescence imaging, a fundamentally different method was demonstrated based on a concept of ultrasound-switchable fluorescence. The results showed that a small fluorescent tube with a diameter of 180 lm at a depth of 20mm in an optical scattering medium (l0 s 3:2 and la 0:026 cm 1) can be clearly imaged with a size of 260 lm. The depth-to-resolution ratio is shown to be about one order of magnitude better than other deep-tissue fluorescence imaging techniques.