Effects of ageing on dermal echogenicity.

Abstract

Changes in the dermis associated with ageing can be detected by high-frequency skin ultrasonography. In photoaged skin, this technique shows a subepidermal low echo-genic band (SLEB) that is probably an ultrasound manifestation of elastosis and oedema in the papillary dermis. Since some authors found an association between age and SLEB thickness or its echogenicity on exposed sites, it has been proposed to use these parameters to quantify skin photoageing. To determine whether SLEB can be used as a quantitative marker of ageing, its prevalence was determined on forearm skin in a group of 55 individuals (age 18-57 years). The size of SLEB has been measured by quantifying the number of low echogenic pixels in the subepidermal area, which is an accurate method for assessing SLEB severity. The prevalence of SLEB increased with age, but SLEB was also present in young subjects. The echogenicity of the subepidermal area did not show any age dependence. However, when a ratio of echogenicity between upper and lower dermis was calculated, a linear dependence on age was found. This study indicates that skin echogenicity measured as a ratio between the upper and lower dermis may be used to objectively estimate photoageing.