Blood-flow oscillations differ markedly between skin sites, so measurements at one location may misrepresent overall microcirculation.
Researchers measured spontaneous skin blood-flow oscillations at four traditional acupuncture-point locations in participants with diabetes, hypertension, both conditions, or neither. They used laser Doppler flowmetry to record local blood flow and applied frequency-based signal analyses, including Fourier, Hilbert–Huang, and wavelet methods, to characterise oscillation patterns and distinguish physiological signals from noise.
The blood-flow oscillation spectra varied across measurement sites in healthy participants and in those with diabetes or hypertension. This pronounced site-to-site heterogeneity suggests that local vessel behaviour is not uniform, meaning a single skin measurement cannot reliably represent the wider state of microcirculation.
