Laser Doppler Fluximetry in Cutaneous Vasculature: Methods for Data Analyses

Sophie J Y Huang; Xuan Wang; Brayden D Halvorson; Yuki Bao; Stephanie J Frisbee; Jefferson C Frisbee; Daniel Goldman

doi:10.1159/000538718

Laser Doppler Fluximetry in Cutaneous Vasculature: Methods for Data Analyses

J Vasc Res. 2024 May 15:1-15. doi: 10.1159/000538718. Online ahead of print.

Authors

Sophie J Y Huang¹, Xuan Wang², Brayden D Halvorson², Yuki Bao³, Stephanie J Frisbee^{4

5

6}, Jefferson C Frisbee², Daniel Goldman^{2

3}

Affiliations

¹ Departments of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.
² Medical Biophysics, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.
³ Biomedical Engineering, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.
⁴ Pathology and Laboratory Medicine, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.
⁵ Epidemiology and Biostatistics, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.
⁶ Lawson Health Research Institute, London, Ontario, Canada.

PMID: 38749406
DOI: 10.1159/000538718

Abstract

Introduction: Acquisition of a deeper understanding of microvascular function across physiological and pathological conditions can be complicated by poor accessibility of the vascular networks and the necessary sophistication or intrusiveness of the equipment needed to acquire meaningful data. Laser Doppler fluximetry (LDF) provides a mechanism wherein investigators can readily acquire large amounts of data with minor inconvenience for the subject. However, beyond fairly basic analyses of erythrocyte perfusion (fluximetry) data within the cutaneous microcirculation (i.e., perfusion at rest and following imposed challenges), a deeper understanding of microvascular perfusion requires a more sophisticated approach that can be challenging for many investigators.

Methods: This manuscript provides investigators with clear guidance for data acquisition from human subjects for full analysis of fluximetry data, including levels of perfusion, single- and multiscale Lempel-Ziv complexity (LZC) and sample entropy (SampEn), and wavelet-based analyses for the major physiological components of the signal. Representative data and responses are presented from a recruited cohort of healthy volunteers, and computer codes for full data analysis (MATLAB) are provided to facilitate efforts by interested investigators.

Conclusion: It is anticipated that these materials can reduce the challenge to investigators integrating these approaches into their research programs and facilitate translational research in cardiovascular science.

Keywords: Blood flow regulation; Computational analyses; Data analytics; Microcirculation; Perfusion imaging.