Evaluation of the Stratum Corneum Exfoliated by Tape Stripping Method (No. 1)

Stratum corneum collected by the tape stripping shows various appearances in terms of the amount, the thickness and the unevenness. The variations of the stripped states are considered to reflect the states of the outermost stratum corneum as well as the epidermis. Accordingly, the quantitative study of the stripped stratum corneum pattern is considered to enable us to evaluate the skin condition. Therefore, we developed a numerical method with image analysis to study the stripped stratum corneum pattern.In measuring the pattern of the stripped stratum corneum, the light transmission images of the stripped tapes were input into the image analysis system to make the analyzed image. According to intensity and distribution of analyzed image on a gray level, the following five parameters were defined as numeric value; 1. the stripped amount, 2. the thickness of the stripped stratum corneum, 3. the unevenness of the size of the stratified stripped part, 4. the unevenness of the steric position of the stratified stripped part and 5. the unevenness of the distribution of the stripped amount.Each parameter of the stripped stratum corneum patterns showed negative correlations with hydration state as well as water holding capacity, while it showed a positive correlation with transepidermal water loss (TEWL).The numeric method with the image analysis of these stripped stratum corneum was useful for evaluating the effect of humectants.