Peter Clarys

Skin color measurements: comparison between three instruments: the Chromameter®, the DermaSpectrometer® and the Mexameter®

Background/aims: Two types of skin reflectance instruments are available nowadays for the determination of skin color: a tristumulus colorimeter (Chromameter from Minolta) using the CIE L*a*b* color system and the narrow‐band simple reflectance meters (DermaSpectrometer from Cortex and Mexameter from Courage‐Khazaka) using the erythema/melanin indices. The purpose of this study was to compare the capabilities of the three instruments (sensitivity, repeatability and correlation) in vitro and in vivo.

Non-invasive electrical measurements for the evaluation of the hydration state of the skin: comparison between three conventional instruments - the Comeometer®, the Skicon® and the Nova DPM®

Some electrical properties of the skin may be related to the water content of the horny layer, and measurements of impedance and/or capacitance have been used to assess the hydration state of the skin surface. This study was designed to compare three commercially available instruments used in dermato‐cosmetic research, namely, the Corneometer CM 825, the Nova DPM 9003 and the Skicon‐200.

In vitro calibration of the capacitance method (Corneometer CM 825) and conductance method (Skicon‐200) for the evaluation of the hydration state of the skin

A major problem with electrical measurements of the capacitance of the skin using the well kwown capacitance method (Corneometer) resides in the fact that the results of this instrument are expressed as arbitrary capacitance hydration units that are not directly related to real electrical units or to the water content of the horny layer. The purpose of this study was to establish a calibration of the capacitance method using a simple in vitro simulation system of the horny layer.

A comparative study of the effects on the skin of a classical bar soap and a syndet cleansing bar in normal use conditions and in the soap chamber test

Background/aims: The skin irritation potential of a body cleansing product is often compared under exaggerated test conditions, although the product is intended to be used at home with repetitive and brief contact with the skin. The aim of this study was to determine how much patch testing is predictive of the clinical, sub‐clinical and subjective cutaneous effects of products used at home by consumers for their normal hygienic cleansing.

The Visi-Chroma VC-100®: a new imaging colorimeter for dermatocosmetic research

Background/aims: It was the aim of this study to carry out a comparative evaluation in vitro on standardized color charts and in vivo on healthy subjects using the Visi‐Chroma VC‐100®, a new imaging tristimulus colorimeter and the Minolta Chromameter CR‐200® as a reference instrument. The Visi‐Chroma combines tristimulus color analysis with full color visualization of the skin area measured. The technical performances of both instruments were compared with the purpose of validating the use of this new imaging colorimeter in dermatocosmetic research.

Sebumetry and Sebumtape

Skin surface lipids (SSL) are a mixture of epidermal lipids and lipids from the sebaceous glands (sebum). Epidermal lipids are found on the whole body and are the sole component of SSL in anatomical regions where no or only few sebaceous glands are present. High quantities of SSL are present on cutaneous areas with many sebaceous glands such as the face (forehead, nose and cheeks), the scalp and the upper parts of the trunk and of the back where sebum may make up to 95–97 % of SSL.