In vivo microvascular flow quantification in the mouse brain using row-column ultrasound localization microscopy and...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Medical Imaging

Background:

• Cerebral microvascular disruption is key in neurological disorders like stroke and tumors.
• High-resolution in vivo imaging of brain microvasculature is crucial for understanding these conditions.
• Ultrasound localization microscopy (ULM) offers noninvasive, subwavelength resolution imaging but is mainly 2D.

Purpose of the Study:

• To develop and validate in vivo transcranial 3D ultrasound localization microscopy (ULM) for mouse brain imaging.
• To create a framework for analyzing ULM data to construct flow-directed vascular graphs.
• To differentiate and quantify artery-like and vein-like vascular segments and their flow-radius relationships.

Main Methods:

• Utilized row-column arrays (RCA) for transcranial 3D ULM in mice.
• Developed a microbubble tracking analysis framework to build vascular graphs.
• Quantified flow and radius relationships within distinct vascular subgraphs across anatomical regions.

Main Results:

• Successfully implemented in vivo transcranial 3D ULM in the mouse brain.
• Established a novel framework to generate flow-directed vascular graphs from ULM data.
• Demonstrated the ability to differentiate and quantify artery-like and vein-like cerebral vasculature.

Conclusions:

• The developed 3D ULM framework enables high-sensitivity in vivo microvascular imaging and quantification in mice.
• This approach provides a scalable platform for preclinical neurovascular studies in both healthy and diseased states.
• The flow-directed vascular graph analysis offers new insights into cerebral hemodynamics and microvascular structure.