Cutaneous photoaging: Description and algorithms

Skin aging and photoaging are the result of long-term biological processes that are difficult to study but easily recognized clinically.1 Photoaging has both chronological and UV exposure components, for a recent review see Rittie and Fisher.2 Photoaging describes the earlier portion of the spectrum of disease that begins with healthy skin and ends with malignant disease. Along the path to malignant disease there are hallmarks of photoaging. These include visible pigmentation responses, wrinkling, skin sagging, and premalignant lesions called actinic keratoses. Both the epidermis and dermis are significantly altered during photoaging. This is due to cleaved collagen and accumulating elastin in the dermis, commonly called solar elastosis.