A reduced aperture allows for transcranial focus localization at lower pressure

Area of Science:

• Biomedical Engineering
• Neuroscience
• Medical Imaging

Background:

• Accurate localization of transcranial focused ultrasound (tFUS) is crucial for targeted brain interventions.
• Magnetic resonance acoustic radiation force imaging (MR-ARFI) is used for tFUS localization but requires high pressures that may damage tissue.

Purpose of the Study:

• To develop a tFUS localization method that reduces acoustic pressure while maintaining displacement accuracy.
• To enable safer and more reliable neuromodulation experiments by mitigating MR-ARFI-induced confounds.

Main Methods:

• Utilized reduced apertures on a phased array transducer for tFUS beam generation.
• Compared displacement generated by reduced apertures to full aperture configurations.
• Measured free field acoustic pressure levels.

Main Results:

• Reduced apertures generated comparable tissue displacement to full apertures.
• Achieved a 20% reduction in free field acoustic pressure.
• Demonstrated feasibility of lower-pressure tFUS localization.

Conclusions:

• Reduced aperture configurations offer a safer alternative for MR-ARFI-based tFUS localization.
• This method enhances the precision and safety of focused ultrasound in the brain.
• Potential to improve the clinical translation of tFUS therapies.