PHOTOAGING VERSUS INTRINSIC AGING - A MORPHOLOGIC ASSESSMENT OF FACIAL SKIN

Histologic studies have become increasingly important in recognizing m orphologic differences in photoaged versus intrinsically aged skin. Ea rlier histologic studies have attempted to evaluate these changes by e xamining anatomical sites which are not comparable, such as face and b uttocks. As part of a multicenter study, we have quantitatively examin ed a panel of 16 histologic features in baseline facial skin biopsies from 158 women with moderate to severe photodamage. When compared to t he postauricular area (photo protected), biopsies of the crow's feet a rea (photo exposed) had a twofold increase in melanocytes and a statis tically significant increase in melanocytic atypia (p < .0001) and epi dermal melanin (p < .0001). Other epidermal changes included reduced e pidermal thickness (p < .01), more compact stratum corneum (p < .0001) and increased granular layer thickness (p < .0001) in the crow's feet skin. There was increased solar elastosis (p < .0001), dermal elastic tissue (p < .0001), melanophages (p < .0001), perivascular inflammati on (p < .05) and perifollicular fibrosis (p < .01) but no change in th e number of mast cells or dermal mucin ill the photo exposed skin. Our data document quantitative differences in photoaged versus intrinsica lly aged facial skin and provides the groundwork for future studies to evaluate the efficacy of new treatments for photoaged skin.