Microbubble Track-based Functional Ultrasound Localization Microscopy in Awake Mice.

Area of Science:

• Neuroimaging
• Ultrasound technology
• Neuroscience

Background:

• Functional neuroimaging in rodents faces a trade-off between sensitivity and spatial resolution.
• Conventional functional ultrasound (fUS) offers high sensitivity but limited resolution.
• Functional ultrasound localization microscopy (fULM) provides super-resolution but lower sensitivity.

Purpose of the Study:

• To develop a novel method to enhance the functional imaging sensitivity of fULM.
• To overcome the compromise between sensitivity and spatial resolution in rodent brain imaging.
• To enable faster and more sensitive neural activity detection using fULM.

Main Methods:

• Developed a microbubble (MB) track-based hemodynamic activity estimation method.
• Utilized functional correlation analysis on entire MB movement tracks, not just centroids.
• Implemented fULM imaging in awake mice using indwelling jugular vein catheters.

Main Results:

• Successfully enhanced fULM functional imaging sensitivity without sacrificing spatial resolution.
• Demonstrated significantly faster detection of activated brain regions (under 5 stimulation cycles).
• Reduced required acquisition time by over 50% compared to conventional fULM.

Conclusions:

• The novel MB track-based method significantly improves fULM sensitivity and efficiency.
• This technique offers a powerful tool for studying neural activity in awake rodents.
• The approach accelerates neuroimaging, enabling quicker insights into brain function.