[Skin circulation--measurements with laser-doppler]

The change in the skin blood flow (SkBF) due to vasoconstriction or vasodilation of the cutaneous vessels is a thermoregulative response during cold or heat stress, respectively. SkBF is estimated in different ways, for instance by measuring body and skin temperature, by venous occlusion plethysmography or by radioactive xenon 133 clearance. The application of laser light based on Doppler shift is a relatively new method for SkBF measurement. At present, several companies operating throughout the world produce laser-Doppler flowmeters. The laser-Doppler method is designed particularly for cutaneous tissues and it facilitates monitoring of the blood flow, however, the measurement results are relative. Depending on the wavelength, the laser light penetrates into the tissue at different depths (from 0.6 to 1.5 mm). The laser light with the wavelength of 632.8 nm enables the measurement of thermoregulative and nutritional blood flow in the skin. The range of the measurement and application of the device provide an opportunity for developing a universal standard. The European Community has published a guide for laboratory quality assurance aimed at improving the standard of measurement records.