W. Wigger- Alberti
(1), M. Keskin (1), G. Feistkorn (2), K.P. Wilhelm (1)
of patch test reactions due to hair dyes with the Laser doppler perfusion scanning
proDERM Institute for Applied Dermatological Research GmbH, D 22869 Schenefeld,
(2) Wella AG, D 64295 Darmstadt, Germany
The interpretation of test reactions of epicutaneous patch tests might
be difficult in cases where coloured test products such as hair dyes have to be
assessed. The subjective clinical scoring is influenced by the colour and even
the benefit of colorimeters is limited. The aim of the present study was to investigate.the
usefulness of the laser Doppler perfusion technique to investigate skin irritation
alter application of hair dyes with different irritant potential.
In order to basically test the practicability of this approach SLS was
added to a hair dye at different concentrations (0.5%, 1%, 2%). Products were
applied to the forearms of 15 volunteers. On day 1 and 3 visual sconng and instrumental
measurements (chromametry, TEWL and Laser Doppler perfusion technique) were performed.
With visual scoring a significant difference was only detected an areas
without dye, between 0.5% SLS and 2% SLS. With TEWL and LDI measurements significant
differentes were detected between the dye without irritant and all test products
with dye and 1% or 2% SLS. Chromametry, however, did not show differentes that
could plausibly be correlated to the irritation potential of the test products.
Dependent an the type of irritant TEWL and Laser Doppler perfusion imaging
are recommended as the methods of choice when evaluating skin irritation potential
of coloured test products.