Multiscale optoacoustic assessment of skin microvascular reactivity in carotid artery disease

Microvascular endothelial dysfunction may provide insights into systemic diseases, such as carotid artery disease. Raster-scan optoacoustic mesoscopy (RSOM) can produce images of skin microvasculature during endothelial dysfunction challenges via numerous microvascular features. Herein, RSOM was employed to image the microvasculature of 26 subjects (13 patients with single carotid artery disease, 13 healthy participants) to assess the dynamics of 18 microvascular features at three scales of detail, i.e., the micro- (<100 μm), meso- (≈100–1000 μm) and macroscale (<1000 μm), during post-occlusive reactive hyperemia challenges. The proposed analysis identified a subgroup of 9 features as the most relevant to carotid artery disease because they achieved the most efficient classification (AUC of 0.93) between the two groups in the first minute of hyperemia (sensitivity/specificity: 0.92/0.85). This approach provides a non-invasive solution to microvasculature quantification in carotid artery disease, a main form of cardiovascular disease, and further highlights the possible link between systemic disease and microvascular dysfunction.