Noninvasive monitoring of plant-based formulations on skin barrier properties in infants with dry skin and risk for atopic dermatitis

Background

Dry skin and the associated impaired epidermal barrier function are postulated to constitute a major element in the development of atopic dermatitis.

Objective

The aim of this study was to evaluate the effect of two plant-based formulations on the epidermal barrier function in a defined cohort of infants with a predisposition for atopic dermatitis.

Methods

Over a period of 16 weeks, 25 infants who were ages 3 to 12 months and had an atopic predisposition and dry skin received two emollients that contained pressed juice of the ice plant. The infants received both cream and lotion on the forearm, only cream on the face, and only lotion on the leg. Stratum corneum hydration (SCH), transepidermal water loss (TEWL), skin surface pH, and sebum were assessed on the infants’ forehead, leg, and forearm. The Scoring Atopic Dermatitis (SCORAD) index was used for the clinical assessment.

Results

SCH significantly increased in all body regions that were assessed. The forearm and leg revealed stable levels of pH and TEWL, but a decline in pH (week 16) and TEWL (week 4) was noted on the forehead. At week 16, sebum levels were lower on the forehead compared with those at baseline. SCORAD scores improved significantly during the study.

Conclusion

A daily application of both emollients was associated with increased SCH levels and a stable course of TEWL, pH, and sebum on the forehead except for the forehead when compared with the forearm and leg. Clinically, improved SCORAD scores were noted.

Relation between skin micro-topography, roughness, and skin age

BACKGROUND

The topography of the skin surface consists of lines, wrinkles, and scales. Primary and secondary lines form a network like structure that may be identified as polygons. Skin surface roughness measurements are widely applied in dermatological research and practice but the relation between roughness parameters and their anatomical equivalents are unclear. This study aimed to investigate whether the number of closed polygons (NCP) per measurement field can be used as a reliable parameter to measure skin surface topography. For this purpose, we analysed the relation between skin surface roughness parameters and NCP in different age groups.

METHODS

Images of the volar forearm skin of 38 subjects (14 children, 12 younger, and 12 older adults) were obtained with the VisioScan VC98. The NCP was counted by three independent researchers and selected roughness parameters were measured. Interrater reliability of counting the number of closed polygons and correlations between NCP, roughness parameters, and age were calculated.

RESULTS

The mean NCP/mm² in children was 3.1 (SD 1.1), in younger adults 1.0 (SD 0.7), and in older adults 1.0 (SD 0.9). The interrater reliability was 0.9. A negative correlation of NCP/mm² with age was observed, whereas measured roughness parameters were positively associated with age. NCP/mm² was weakly related to skin roughness.

CONCLUSION

The NCP/mm² is a reproducible parameter for characterizing the skin surface topography. It is proposed as an additional parameter in dermatological research and practice because it represents distinct aspects of the cutaneous profile not covered by established roughness parameters.

Reliability and validity of two in vivo measurements for skin surface topography in aged adults

BACKGROUND

The non-contact optical methods phaseshift rapid in vivo measurement of skin (PRIMOS) and surface evaluation of living skin (SELS) are widely applied for measuring skin surface topography. The aims of the present study were to evaluate reliability and validity of these methods and to compare skin roughness intraindividually.

METHODS

SELS and PRIMOS measurements were performed on four skin areas of the left and right volar forearms in 12 healthy elderly subjects. Reliability and correlations were analyzed for Visioscan® and PRIMOS roughness parameters. Student's t-tests for estimating differences between contralateral volar forearm sites were applied.

RESULTS

ICC coefficients of the Visioscan® roughness estimates ranged between 0.50 and 0.95 and of the PRIMOS measurements between 0.01 and 1.00. The Visioscan® parameters SEr, SEsm, Rmax, and Rz, and the PRIMOS parameters Ra, Rz, Smax, Wt, and Sz showed most significant correlations with each other and to additional roughness parameters. Mean roughness differences between contralateral forearm skin areas ranged between 0.0 (SEsc) and 6.7 (Rmax).

CONCLUSIONS

The Visioscan® parameters SEr, Rmax, and Rz showed most reliable and valid values and were largely comparable on contralateral forearm skin sites in elderly subjects. Rmax, Rz, and Ra should be preferred for measuring skin surface topography with PRIMOS.