Measuring the steady-state value and the dynamics of the skin blood flow using the non-contact laser speckle method

The non-contact laser speckle method provides a measure of skin blood flow with a time resolution of 1 s. Information about different characteristics of the blood flow can be obtained from measurements of the steady state and from the time course during ischaemia and reactive hyperaemia. Special signal processing, a microprocessor and a computer program facilitate the analysis of the data. They consider disturbances which come from a common tissue movement and from convulsions of the limbs. Measurements prove a decreased steady-state value and prolonged half-times during ischaemia and reactive hyperaemia when patients with peripheral arterial occlusive disease are compared with healthy subjects.