Skin blood flow changes during local arm heating: comparison between the laser-Doppler and frequency-corrected thermal clearance measurement

摘要

We compared two different techniques for non-invasive registration of fingertip skin blood flow changes in 5 healthy volunteers during local arm heating in the water bath from 21 °C to 42 °C. The laser-Doppler flowmetry (LDF) probe was attached to the pulp of the index finger, while the thermal clearance (TC) probe was fixed to the pulp of the middle finger. Computer simulation method, provided by the MATLAB package, was introduced to speed up the frequency response of the TC probe. By correlation analysis we evaluated the similarity of LDF and TC recordings. The median correlation coefficient for the relationship LDF versus TC equaled 0.74, the range being from 0.63 to 0.82. After an introduction of the computer-based frequency correction, the correlation increased till 0.88 with the range from 0.82 to 0.91. The corresponding improvement in r~2 ("goodness to fit") was 41%.