Day-to-day variability in cutaneous microcirculation measured with multi-exposure laser speckle contrast imaging and multispectral imaging

Introduction

Dysfunctional microcirculation is associated with cardiovascular risk factors, chronic disease such as diabetes and acute conditions like septic shock. The non-invasive optical techniques laser Doppler flowmetry (LDF) and diffuse reflectance spectroscopy (DRS) are often used to measure perfusion and oxygen saturation, but are limited to single-point measurements making them sensitive to spatial variations. The imaging modalities multi-exposure laser speckle contrast imaging (MELSCI) and multi-spectral imaging (MSI) overcome this limitation by capturing the parameters in a larger skin area.

Aim

To assess the day-to-day variability of speed-resolved perfusion and oxygen saturation in the forearm and plantar foot at baseline and peak response following arterial occlusion-release, while also evaluating sex and age influences.

Method

MELSCI and MSI were used on 48 participants (12 males and 12 females aged 20–30, and 12 males and 12 females aged 50–60) across two measurements within a week. Each measurement lasted 60 min, with perfusion and oxygen saturation being measured at baseline (10 min), during occlusion (5 min), and post-occlusion (5 min) as spatial averages over the entire imaged tissue area.

Results

Older age was associated with higher foot perfusion at peak (p = 0.006). Variability (CV) ranged from 1.4 % to 19 %, with foot low-speed perfusion showing a sex- and age-related difference at peak (p = 0.007).

Conclusion

Age and sex influenced microcirculatory parameters, aligning with prior research. MELSCI and MSI demonstrated low day-to-day variability, making them promising techniques for clinical disease monitoring. The variability of MELSCI perfusion was lower than previously reported for laser speckle contrast imaging (LSCI) perfusion.