This study evaluated the efficacy and short-term skin tolerability of a topical foot-care formulation for improving heel skin keratinization. In addition, it examined whether video microscopic image analysis based on Otsu thresholding could provide an...
This study evaluated the efficacy and short-term skin tolerability of a topical foot-care formulation for improving heel skin keratinization. In addition, it examined whether video microscopic image analysis based on Otsu thresholding could provide an objective basis for assessing changes in heel keratin status within a human application study.
A self-controlled human application design was used to observe changes in heel keratinization before and after product use. Participants applied the topical foot-care formulation to the heel according to a standardized protocol, and heel skin images were obtained under controlled measurement conditions. The acquired images were analyzed through video microscopic image analysis and Otsu thresholding, while skin responses and user-perceived changes were evaluated through investigator observation, participant reporting, and structured questionnaires.
The topical foot-care formulation produced a statistically significant improvement in heel skin keratinization after application, and the improvement was maintained during repeated use. No clinically meaningful adverse skin reactions were observed or reported. Subjective evaluations also supported the instrumental findings, indicating favorable perceptions of exfoliating effect, moisturization, heel skin condition, and product usability.
These findings suggest that the topical foot-care formulation may be effective for improving heel skin keratinization and may be used as a practical external foot-care approach. Furthermore, video microscopic image analysis combined with Otsu thresholding appears to be an appropriate objective method for evaluating heel keratin changes in cosmetic efficacy research.