The clinical evaluation of cosmetic or dermatological products is now mandatory to provide proof of an active ingredient’s or a formulation’s efficacy, and to successfully penetrate the personal care market. Thanks to the latest research in medical and industrial imaging, cosmetic companies are able to accurately quantify the features of skin’s appearance as correlated to visual perception. A great number of devices to perform skin measurements are available. Some are specialized in measuring physical and chemical skin properties; others focus on describing skin structure, its morphology and/or visual appearance. Image analysis and processing are part of the second category, as they are designed to correlate measurements with the visual interpretation of experts, dermatologists or cosmetic users.
Quantifying changes in skin’s color, evaluating its brightness and texture, measuring dark spots, etc., can all be performed using skin imaging, which provides substantial benefits, compared with traditional techniques. Unlike colorimeters or gloss meters, image analysis is carried out without contacting skin and therefore does not cause devascularization, which can influence skin color. Through image processing, skin brightness can be measured in a reproducible way that is independent of the skin’s topology and does not alter the measurement area. The notion of spatiality also enables precise measurements of the color of blotches, hair and lesions while ignoring the surrounding skin.
Medical imaging can be transposed to dermo-cosmetic and cosmetic fields and used at each stage of product evaluation—from screening an active ingredient in vitro, to its use in a finished product tested on volunteers. Medical imaging provides a reproducible standard among all images, to extract the relevant information and accurately quantify claims. This paper will focus on a skin image analysis technique that can be used to prove specific claims by highlighting the performance of porous polyamide microspheres in personal care formulations.
