Postural Skin Colour Changes during the Corticosteroid Blanching Assay

Objective: To assess the effect of the position of a limb (dependency) on the cutaneous vasoconstrictor (blanching) assay (VCA) using topical corticosteroid preparations. Method: Two studies were performed on the forearms of healthy volunteers using tristimulus reflectance colorimetric assessments. The first one conducted in 60 normal adults aimed at quantifying the range of variation in the skin chromaticity a* when the arm was successively positioned horizontally and vertically, either in the upward or downward direction. In the second study, 16 volunteers were selected according to a weak spontaneous postural dependency of the limb in a* (