Quantifying microvascular responses to local heating using optical coherence tomography: Comparison between skin...

Area of Science:

• Cutaneous microcirculation research
• Vascular physiology
• Medical imaging techniques

Background:

• Limited understanding of regional and sex-specific differences in skin microvasculature due to technical limitations.
• Need for advanced imaging to quantify microvessel characteristics.

Purpose of the Study:

• To compare microvessel diameter, velocity, flow, and density across four skin regions (back, forearm, foot, thigh).
• To investigate these parameters at rest and following local heating (LH).
• To identify potential sex-based differences in microvascular responses.

Main Methods:

• Utilized a novel optical coherence tomography (OCT) approach combined with laser Doppler flowmetry (LDF).
• Measurements were taken on 30 healthy adults (15 males, 15 females) at four distinct anatomical sites.
• Conditions included resting state (33°C) and local heating (44°C for 30 min).

Main Results:

• Baseline: The back showed significantly larger microvessel diameter, speed, flow, and density compared to other sites.
• Local Heating Response: The back and foot exhibited the smallest increases in diameter. The foot had the least change in speed and flow, while the back showed the smallest change in density.
• Sex Differences: Males had larger baseline diameters and flows. Females showed greater increases in thigh speed and forearm density post-heating.

Conclusions:

• Significant regional variations exist in cutaneous microvascular function, affecting diameter, speed, flow, and density, both at rest and during thermal stress.
• Sex-specific differences in microvascular responses to local heating were observed, particularly in speed and density.
• OCT provides a valuable tool for detailed analysis of skin microvascular dynamics and regional variations.