Real-time scanning slit confocal microscopy of the in vivo human cornea.

We describe a new, nonapplanating, real-time scanning slit confocal microscope that produces unique real-time video images of the in vivo human cornea. This new real-time slit scanning confocal microscope produces en face, single-video-frame images (2-µm sections) with high contrast through the full thickness (500 µm) of the normal cornea. No frame averaging or digital image enhancement is required. The images of superficial epithelial cells, wing cells, basal epithelial cells, corneal innervation, nuclei of stromal keratocytes, and the cell bodies of the stromal keratocytes in the posterior stromal region demonstrate the unique real-time imaging characteristics. The microscope is equipped with waterimmersion microscope objectives of high numerical aperture. The microscope objective does not flatten or distort the cornea; a polymer gel is used to couple the microscope objective optically to the cornea.