Protection and Therapy of Photoaging

Chronic and repeated sun exposure causes photoaging skin that includes solar lentigines, wrinkles, changes of texture, benign tumors, and cutaneous cancers. Various symptoms of photoaging have been a great concern in dermatology. Photoprotection using sunscreens is recommended to prevent these signs. Two measures, sun protection factor (SPF) for UVB and protection grade of UVA (PA) for UVA, are described on the label of sunscreens. Our recent investigation revealed defects in the correct knowledge of SPF and PA and a relationship between freckles and sun-exposure history. Education in the appropriate use of sunscreens and the significance of SPF and PA is needed. Solar lentigines on the face decrease quality of life. Previous laser therapies cause erosion and crusts with downtime for the treatment of pigmentary lesions. Then, intense pulsed light (IPL) sources have been developed as noninvasive and nonablative modalities for facial solar lentigines. We demonstrated clinical effectiveness of an IPL source for solar lentigines and ephelides on the face with well tolerability. Then, we performed a histopathological study that indicated IPL produced highly selective photothemolysis of melanin pigment in the lesions of solar lentigines, leading to the clinical improvement. Moreover, we showed clinical effects of a novel IPL source on solar lentigines and ephelides. In the future, phototherapy including IPL sources will develop with more effectiveness and safety.