System for controlled mechanical therapies of the brain

Area of Science:

• Biomedical Engineering
• Neuroscience
• Acoustic Physics

Background:

• Transcranial focused ultrasound (tFUS) offers non-invasive alternatives to surgery for brain therapies.
• Mechanical therapies via ultrasound are desirable due to localized effects and reduced heating.
• A need exists for controlled systems for mechanical brain therapies.

Purpose of the Study:

• To develop and evaluate a prototype transcranial focused ultrasound system for controlled mechanical brain therapies.
• To assess the system's performance across ex-vivo human skulls, focusing on acoustic aberrations.

Main Methods:

• Developed a low-frequency (325 kHz) tFUS system designed to enhance mechanical effects.
• Evaluated transcranial performance using 21 ex-vivo human skulls.
• Measured focal point shift, focal volume changes, and pressure field attenuation without phase correction.

Main Results:

• Achieved a low mean focal point shift (1.2 mm) and minimal focal volume increase (18%) without phase correction.
• Observed moderate acoustic pressure attenuation (average 67%) across skulls.
• Demonstrated reduced susceptibility to skull-induced ultrasound aberrations at lower frequencies.

Conclusions:

• The developed low-frequency tFUS system shows potential for non-invasive mechanical brain therapies.
• The prototype minimizes skull-related ultrasound distortions, enabling targeted mechanical effects.
• Further in-vivo validation, including thermometry and safety studies, is necessary for clinical translation.