Biophysical characteristics of healthy skin and nonlesional shin in atopicdermatitis: Short-term effects of ultraviolet A and B irradiation

The present study was designed to evaluate basic differences in surface str ucture and viscoelastic properties of nonatopic versus atopic skin and facu ltative acute changes following ultraviolet irradiation. Therefore, biophys ical measurements by means of profilometry and cutometry were carried out o n sun-protected unaffected gluteal skin areas in both groups before and 24 h after single UVA and UVB irradiations. The results indicate that the clin ically unaffected skin of patients with atopic eczema differs from normal s kin in terms of increased roughness parameters, but not concerning depth of furrows or viscoelastic properties (viscosity and biological elasticity, c utometrically calculated). Single UVA irradiation with 50 J/cm(2) induced n either measurable changes in the skin's surface structure nor in its viscoe lastic properties in both groups after 24 h. However, irradiation with a si ngle erythemogenic dose of 1 MED UVB was followed by a short-term significa nt increase in the depths of furrows and decrease in biological elasticity in normal and atopic skin, accompanied by an increase in viscosity in norma l skin. Copyright (C) 2000 S. Karger AG, Basel.