Assessing hyperthermia-induced vasodilation in human skin in vivo using optoacoustic mesoscopy (Conference Presentation)

Abstract

The aim of this study was to explore the unique imaging abilities of optoacoustic mesoscopy to visualize skin structures and microvasculature with the view of establishing a robust approach for monitoring heat-induced hyperemia in human skin in vivo. Abnormalities in the structure and function of skin vasculature are increasingly recognized as hallmarks of several systemic disorders. Purely optical techniques can sense changes in skin perfusion, but they lack reproducibility and resolution to quantify the behavior of vessels in deep skin. Using raster-scan optoacoustic mesoscopy (RSOM), we investigated whether optoacoustic mesoscopy can identify changes in skin response to local heating at microvasculature resolution in a cross-sectional fashion through skin in the human forearm. We visualized the heat-induced hyperemia for the first time with single-vessel resolution throughout the whole skin depth. We quantified changes in total blood volume in the skin and their correlation with local heating. In response to local heating, total blood volume increased 1.83- and 1.76-fold, respectively, in the volar and dorsal aspects of forearm skin. We demonstrate RSOM imaging of the dilation of individual vessels in the skin microvasculature, consistent with hyperemic response to heating at the skin surface. Our results demonstrate great potential of optoacoustic dermoscopy for elucidating the morphology, functional state and reactivity of dermal microvasculature, with implications for diagnostics and disease monitoring in dermatology.