MR-guided transcranial brain HIFU in small animal models

Area of Science:

• Neuroscience
• Biomedical Engineering
• Medical Imaging

Background:

• Transcranial high-intensity focused ultrasound (HIFU) shows promise for brain therapy but requires precise targeting and monitoring.
• Ensuring treatment safety and preventing damage to healthy tissues are critical challenges in HIFU procedures.

Purpose of the Study:

• To develop and validate a comprehensive workflow for MR-guided HIFU in the brain.
• To implement novel MR-based techniques for real-time monitoring and safety control during HIFU treatment.
• To assess the feasibility of MR-elastography for evaluating tissue changes post-HIFU.

Main Methods:

• A dedicated MR-compatible HIFU setup was used in a 7 T MRI scanner for experiments in rats.
• MR-acoustic radiation force imaging was employed to detect and quantify tissue displacements in vivo.
• MR-thermometry monitored temperature changes, and MR-elastography assessed tissue stiffness pre- and post-HIFU.

Main Results:

• The study successfully demonstrated in vivo detection of acoustic radiation force-induced tissue displacements in rat brains.
• MR-guided HIFU allowed for accurate localization of the ultrasound focal point and effective temperature monitoring.
• MR-elastography showed potential for non-invasively assessing tissue stiffness changes, with brain elasticity being more sensitive to edema than necrosis.

Conclusions:

• MR-guided HIFU provides a feasible and valuable approach for monitoring transcranial treatments in the brain.
• MR-acoustic radiation force imaging and MR-elastography are effective tools for ensuring the safety and efficacy of HIFU brain therapy.
• The developed workflow offers a comprehensive solution for accurate targeting, monitoring, and control of MR-guided HIFU brain treatments.