title: Observing temperature fluctuations in humans using infrared imaging.
abstract: In this work we demonstrate that functional infrared imaging is capable of detecting low frequency temperature fluctuations in intact human skin and revealing spatial, temporal, spectral, and time-frequency based differences among three tissue classes: microvasculature, large sub-cutaneous veins, and the remaining surrounding tissue of the forearm. We found that large veins have stronger contractility in the range of 0.005-0.06 Hz compared to the other two tissue classes. Wavelet phase coherence and power spectrum correlation analysis show that microvasculature and skin areas without vessels visible by IR have high phase coherence in the lowest three frequency ranges (0.005-0.0095 Hz, 0.0095-0.02 Hz, and 0.02-0.06 Hz), whereas large veins oscillate independently.
authors.affiliation: Naval Medical Research Center, Silver Spring, MD, USA ; National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Wei-Min
authors.initials: WM
authors.lastname: Liu
authors.forename: Joseph
authors.initials: J
authors.lastname: Meyer
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Scully
authors.forename: Eric
authors.initials: E
authors.lastname: Elster
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Gorbach
keywords: infrared imaging; low frequency oscillation; skin microvasculature; thermoregulation; wavelet phase coherence
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