Hyperspectral wide-field-of-view imaging to study dynamic microcirculatory changes during hypoxia

Hyperspectral imaging (HSI) provides a fast, reliable, and noninvasive way for the study of vascular microcirculation in animal models. Rapid hyperspectral imaging of large portions of the microcirculatory preparation is critical for understanding the function and regulation of vascular microcirculatory networks. This report presents the application of an off-the-shelf benchtop HSI linear scanning system to acquire larger field-of-view images of microcirculatory preparations. The HSI line detector was displaced perpendicular to the scanning direction to map larger areas, with a rate of displacement determined by the scanning rate and the exposure time. Analysis of the collected image was used to assess dynamic changes in the microcirculation. The system records dynamic changes in microvascular hemoglobin oxygen (HbO2) saturation and vascular morphology during hypoxia and reoxygenation and has similar acquisition speeds to commonly referenced spectral-scanning HSI systems. In addition, the HbO2 saturations collected via HSI closely correlate with those collected by phosphorescence quenching microscopy. The reported system enables dynamic functional imaging of the microcirculation for broad experimental and clinical applications. NEW & NOTEWORTHY This study presents a novel bench setup and algorithm to measure intravascular hemoglobin oxygen saturation in microcirculation. Wide-field hyperspectral imaging allows for rapid quantification of intravascular changes in hemoglobin saturation. The method described in this manuscript can expand the understanding of oxygen delivery to tissues in vivo.