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Laser system for optical biopsy and in-vivo study of the human skin

The aim of this study was to perform a preliminary evaluation of the diagnostic potential of noninvasive laser-induced autofluorescence spectroscopy (LIAFS) for human skin in vivo. The autofluorescence characterization of tissue relies on different spectral properties of tissue. It was demonstrated a differentiation between normal skin and skin with vitaligo. In our experimental investigation of the autofluorescence spectrum of human skin in vivo a nitrogen laser with excitation wavelength 337 nm was used. Two fluorescence bands were observed at 440 and 490 nm, these were attributed to reduced nicotinamide adenine dinucleotide (NADH) and collagen. The intensity of the NADH emission band was markedly reduced in the skin with vitaligo compared with the normal skin, which could indicate different redox conditions in skin with vitaligo. The autofluorescence spectrum of human skin depends on the main internal absorbers, which are blood and melanin. In this study was described the effect caused by melanin content on the shape of the autofluorescence spectrum of human skin. Human skin fluorescence spectrum might provide dermatologists with important information and such investigations are successfully used now in skin disease diagnostics, in investigation of the environmental factor impact or for evaluation of treatment efficiency. The goal of this work is optimization of detection and diagnosis of hollow organs and skin.