Dynamic infrared imaging for analysis of fingertip temperature after cold water stimulation and neurothermal modeling study

The human hand is considered to be the terminus of the nervous system. It contains numerous capillary vessels, and it plays an important role in the regulation of the autonomic nervous system. We have used infrared thermography and ultrasound Doppler flowmetry to investigate characteristics of the temperature variation of the hand and the blood flow after cold stimuli. We have also developed an image processing algorithm to measure temperature of various parts of the hand via sequential thermal images. Measured results show that local cold stimuli will induce oscillation of temperature, which may be due to neuroregulation during rewarming. Finally, in order to explain the mechanism of autonomic nervous system (ANS) regulation we have developed an ANS regulation model on the basis of the knowledge of the physiology and bioheat transfer. The results computed using our model are in good agreement with the experimental results.