In vivo functional microangiography by visible-light optical coherence tomography

Area of Science:

• Biomedical Optics
• Medical Imaging
• Physiology

Background:

• Microvascular oxygen saturation (sO2) is critical for tissue function.
• Non-invasive measurement of microvascular sO2 remains a significant challenge in biomedical research.

Purpose of the Study:

• To demonstrate the capability of visible-light optical coherence tomography (vis-OCT) for non-invasive in vivo microvascular sO2 measurement.
• To assess vis-OCT's ability to provide simultaneous anatomical and functional information at the capillary level.

Main Methods:

• Utilized vis-OCT for high-resolution 3D anatomical imaging of microvasculature.
• Employed speckle contrast from moving blood cells to enhance microvascular visualization.
• Applied short-time inverse Fourier transforms to analyze optical attenuation and quantify sO2.
• Validated measurements in vivo using hypoxia and hyperoxia challenges in mouse ears.

Main Results:

• vis-OCT successfully visualized capillary-level microvasculature in 3D.
• Quantified in vivo microvascular sO2 with validation against physiological challenges.
• Demonstrated continuous monitoring of dynamic microvascular sO2 changes.

Conclusions:

• vis-OCT is a powerful tool for simultaneous microvascular imaging and sO2 quantification in vivo.
• This technology offers a novel approach to study tissue oxygenation dynamics at the microvascular level.
• vis-OCT has potential applications in various research areas requiring non-invasive assessment of microvascular function.