Development and preliminary testing of a standardized method for quantifying excess water in over-hydrated skin using evaporimetry
ABSTRACT Although evaporimetry (the measurement of water vapour flux density from the skin) has often been used to study the impact on skin hydration of using products such as baby diapers and incontinence pads, it is difficult to interpret results and to compare data from different studies because of the diversity of unvalidated methodologies used. The aim of this work was to develop a robust methodology for measuring the excess water in over-hydrated skin and test it on volar forearm and hip skin which had been occluded with saline soaked patches. Three repeat measurements were made on the volar forearm and the hip of five young (31-44 years) and six older (67-85 years) women and moderately good within-subject repeatability was found for both skin sites for both subject groups. Measurements taken from the hip were significantly higher (P = 0.001) than those from the arm and had larger coefficients of variation (3.5-22.1%) compared to arms (3.0-14.0%). There were no significant differences between young and older skin, implying that women for future studies could be recruited without regard to age. This is the first time that a robust evaporimetric methodology for quantifying excess water in over-hydrated skin has been described and validated, and it will form a solid basis for future work.
[Show abstract] [Hide abstract]
ABSTRACT: Skin over-hydration is a common problem that affects many people who wear incontinence pads or diapers. The aim of this study is to develop a new method for stratum corneum (SC) over-hydration and SC water diffusion coefficient measurements using opto-thermal transient emission radiometry (OTTER) and evaporimetry. With OTTER, we can measure the SC surface hydration and hydration gradient. With evaporimetry, we can measure the time-dependent evaporative drying curves of water vapour flux density (WVFD). The combination of hydration results and WVFD results can yield information on the SC water diffusion coefficient and how it depends on the SC surface hydration level. The results show that SC water diffusion coefficient is non-linearly proportional to the SC surface hydration level. The results also show strong correlations between evaporative drying flux measured using the Evaporimeter and surface hydration estimated from OTTER measurements.International journal of cosmetic science 04/2012; 34(4):328-31. DOI:10.1111/j.1468-2494.2012.00721.x