Multimodality microscope for optical shave biopsy of human skin

Skin, the largest human organ, has diverse cell types and layers. Noninvasive 3D volumetric imaging with high resolution, large field-of-view (FOV), and multicontrast is vital for skin biology and disease diagnosis. Techniques like reflectance confocal, two-photon fluorescence, and second harmonic generation microscopy can be combined in a multimodal microscope for simultaneous multiple contrasts. Traditional xy-z volume mosaicing covers large FOV but suffers from motion artifacts and slow speed. We previously developed xz-y imaging, scanning vertically (x-z plane) and moving skin laterally (y-direction) to reduce motion and speed up 3D acquisition. Here, we improved this system, expanding the single xz plane FOV from 200μm x 200μm to 800μm x 200μm, doubling frame rate to 30 fps, and oversampling to boost signal-to-noise ratio. This enhances volumetric imaging speed by over 8 times, allowing multiple volume strips to be acquired and stitched quickly. We call this “optical shave biopsy.” Optical shave biopsies from various body sites demonstrate its potential for in vivo skin studies, clinical diagnosis, treatment planning, and monitoring.