Deep UV laser scanning microscopy with integrated 1050 nm spectral-domain optical coherence tomography for multi-contrast tissue imaging.

Slide-free microscopy methods for histological imaging in thick, minimally processed tissue specimens are rapidly emerging for surgical margin analysis applications. Here, we report an optical imaging system that combines 266 nm excited fluorescence, 266 nm confocal reflectance, and 1050 nm spectral-domain optical coherence tomography. The deep UV confocal reflectance and DAPI stain emission contrasts provide histology-like imaging at the tissue surface, with virtual H&E staining enabled by deep learning. Cross-sectional OCT extends visualization of tissue morphology beneath the specimen surface with near-infrared depth penetration. A custom reflective objective facilitates simultaneous high resolution, aberration-free imaging of UV confocal reflectance and fluorescence emission with a 0.52 numerical aperture, while transmitting a secondary low numerical aperture OCT beam. Imaging of ex vivo specimens is demonstrated in murine kidney and liver, and human breast tissues.