Skin thickness is an important skin property in cosmetology, dermatology and pharmaceutical science. It varies significantly between the face and other body parts, and changes with age and environment factors.
Changes that markedly affect aesthetics, such as wrinkles, sagging and skin elasticity are the result of physiological changes in the epidermis and dermis layers. Measuring the structural conditions of the epidermis and dermis has, until now, only been possible using complex methods and has required cumbersome equipment.
A non-invasive approach to measuring skin thickness using near infrared light has just been published in the latest issue of the Journal of Near Infrared Spectroscopy by Dr Yuta Miyamae, POLA Chemical Industries, Japan, and his colleagues from School of Science and Technology, Kwansei-Gakuin University, Japan.
Dr Miyamae said “Determining the dermal and epidermal thickness is important for general aesthetics, the use of cosmetics and drugs, optimally positioning skin grafts, and effective massage. Since you can also detect early signs of pathological skin thickening, it is possible to use this knowledge to offer preventative treatment.”
The standard error associated with measuring the total skin thickness using the NIR technique was 25 µm. More exciting were the ability to determine the thickness of the epidermis and dermis to an accuracy of 22 µm and 8 µm, respectively. “In the paper we explain how it is possible to determine the thickness of the dermis through the epidermis and hence not directly seen by the light source,” Professor Ozaki said, “the proposed method is simple, non-destructive and accurate.”
This novel application of near infrared (NIR) spectroscopy offers skin specialists the ability to monitor skin for medical and cosmetic purposes in a cost-effective and harmless manner.
The research is published as Yuta Miyamae, Marie Kawabata, Yumika Yamakawa, Junko Tsuchiya and Yukihiro Ozaki, “Non-invasive estimation of skin thickness by near infrared diffuse reflection spectroscopy—separate determination of epidermis and dermis thickness”, J. Near Infrared Spectrosc. 20(6), 439–446 (2012), doi: 10.1255/jnirs.1024.