Optical coherence tomography in the assessment of acute changes in cutaneous vascular diameter induced by heat stress

Abstract

Optical coherence tomography in the assessment of acute changes in cutaneous vascular diameter induced by heat stress.http://researchonline.ljmu.ac.uk/4156/ Article LJMU has developed LJMU Research Online for users to access the research output of the University more effectively. Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Users may download and/or print one copy of any article(s) in LJMU Research Online to facilitate their private study or for non-commercial research. You may not engage in further distribution of the material or use it for any profit-making activities or any commercial gain.The version presented here may differ from the published version or from the version of the record. Please see the repository URL above for details on accessing the published version and note that access may require a subscription. AbstractThere are limited imaging technologies available that can accurately assess or provide surrogate markers of the in vivo cutaneous microvessel network in humans. In this study, we establish the use of optical coherence tomography (OCT) as a novel imaging technique to assess acute changes in cutaneous microvessel area density and diameter in humans. OCT speckle decorrelation images of the skin on the ventral side of the forearm up to a depth of 500 μm were obtained prior to and following 20-25 mins of lower limb heating in eight healthy males (30.3±7.6 yrs). Skin red blood cell flux was also collected using laser Doppler flowmetry probes immediately adjacent to the OCT skin sites, along with skin temperature.OCT speckle decorrelation images were obtained at both baseline and heating time points. New & NoteworthyThis manuscript examines for the first time the utility of optical coherence tomography (OCT) as a novel imaging technique to visualize and quantify changes in the cutaneous microvasculature in response to acute passive heating. We hypothesized that lower body heating would induce detectible microvascular changes in the skin of the forearm. Our findings demonstrate the capacity of OCT to image vascular structures over multiple time points, and to quantify these changes using automated techniques.

OCT‐based angiography of human dermal microvascular reactions to local stimuli: Implications for increasing capillary blood collection volumes

“…Immediately after heating, whole dermis vessel density and mean vessel diameter increased by approximately 16% and 14%, respectively ( Fig. 3A and B), suggesting the dense microvasculature observed visually is likely due to vasodilation, a natural response of the skin microvasculature to curb overheating and encourage heat loss [31,32]. Similarly, rubbing induced adaptations within all three parameters measured.…”

Effects of Exercise on Vascular Function, Structure, and Health in Humans

“…The well-established increases in peak reactive hyperemia that result from training (outlined above) may, at least in part, be caused by resetting of the wall:lumen ratio. While it is not currently possible to image smaller resistance vessels in humans to confirm Folkow's important ideas regarding the role for wall thickness in pressure regulation, or the impacts of exercise, evolving ultra-high-resolution imaging techniques hold some promise that this will be possible in the future (Carter et al 2016).…”

Blood pressure normalization via pharmacotherapy improves cutaneous microvascular function through NO‐dependent and NO‐independent mechanisms

“…These findings, which indicate no structural alteration occurred with blood pressure normalization, are inconsistent with other published findings, likely due to the different vessels examined and methods used to determine vessel structure. Currently, technology is in its infancy for direct measurements of cutaneous microvessel structure outside of the nail fold. To our knowledge, no studies have been performed to measure cutaneous microvascular diameter in hypertensive subjects.…”