Abstract:We demonstrate high-speed, high-sensitivity, high-resolution optical imaging based on optical frequency-domain interferometry using a rapidly-tuned wavelength-swept laser. We derive and show experimentally that frequency-domain ranging provides a superior signal-to-noise ratio compared with conventional time-domain ranging as used in optical coherence tomography. A high sensitivity of −110 dB was obtained with a 6 mW source at an axial resolution of 13.5 µm and an A-line rate of 15.7 kHz, representing more than an order-of-magnitude improvement compared with previous OCT and interferometric imaging methods.

Highlights d prkdc À/À , il2rga À/À zebrafish reared at 37 C engraft a wide array of human cancers d Growth and therapy responses can be dynamically visualized at single-cell resolution d Combination olaparib and temozolomide kill xenografted human rhabdomyosarcoma d Engrafting patient-derived cancers opens new avenues for personalized therapy Authors

Spectrally encoded confocal microscopy (SECM) is a technique that allows confocal microscopy to be performed through the confines of a narrow diameter optical fiber probe. We present a novel scheme for performing SECM in which a rapid wavelength swept source is used. The system allows large field of view images to be acquired at rates up to 30 frames/second. Images of resolution targets and tissue specimens acquired ex vivo demonstrate high lateral (1.4 mum) and axial (6 mum) resolution. Imaging of human skin was performed in vivo at depths of up to 350 mum, allowing cellular and sub-cellular details to be visualized in real time.