Confocal microscopy of in vivo human skin and cornea
Barry R. Masters
Department of Anatomy and Cell Biology,
Uniformed Services University of the Health Sciences,
4301 Jones Bridge Road, Bethesda, Maryland 20814, USA
In vivo confocal microscopy is a new development in optical imaging of the human body. Several types of confocal imaging microscopes have been developed specifically for in vivo imaging of the human eye and the human skin. A real-time slit scanning confocal microscope has been developed by Dr. A. Thaer for clinical real-time imaging of the living human cornea [1]. This instrument can obtain 10 micron thick optical sections across the full 500 microns of the human cornea. The instrument is designed to produce sharp, high contrast images of the cells in the cornea at video rates. The effect of eye movements is compensated for by the instrument electronics. With this clinical instrument we have observed all cell types in the human cornea, corneal nerves, and the nuclei and cell bodies of stromal keratocytes. A laser scanning confocal microscope has be used to image in vivo human skin. We can obtain optical sections of living human skin in both the reflected light modes and in the autofluorescence mode. Three-dimensional reconstructions have been made of the optical sections of in vivo human skin. Recent developments in confocal microscopes have resulted in new instruments with the capability to observe cellular and subcellular structures in both the living eye and living skin. Two-photon excitation laser scanning microscopy has been used to obtain metabolic functional imaging of the eye [2].