3-D Transcranial Microbubble Cavitation Localization by Four Sensors.

Area of Science:

• Biomedical Engineering
• Acoustic Physics
• Medical Imaging

Background:

• Cavitation is crucial for focused ultrasound (FUS) brain therapies.
• Accurate 3-D cavitation localization enhances targeting and prevents off-target damage.
• Current 3-D detection methods use complex, expensive phased arrays.

Purpose of the Study:

• To investigate the feasibility of using a simple four-sensor system for transcranial 3-D cavitation localization.
• To develop and validate a novel localization algorithm for this purpose.

Main Methods:

• Developed differential microbubble cavitation detection with a time difference of arrival algorithm.
• Utilized four sensors (2.25 MHz center frequency) for detecting cavitation emissions.
• Validated the method using numerical simulations (k-Wave) and ex vivo human skullcap experiments.

Main Results:

• The four-sensor method accurately localized cavitation transcranially in both simulations and experiments.
• Localization accuracy within 30 mm of the sensor network center was 1.9±1.0 mm with a skull.
• Accuracy was comparable to no-skull conditions (1.7±0.5 mm) and minimally affected by sensor position.

Conclusions:

• A simple four-sensor system combined with the proposed algorithm provides effective 3-D transcranial cavitation localization.
• This approach offers a cost-effective and less complex alternative to existing methods.
• Enables improved precision and safety in FUS-mediated brain therapies.