Multi-channel flow phantom for MRI-guided focused ultrasound

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Acoustic Physics

Background:

• Agar-silica phantoms are common in MRgFUS research.
• Previous models did not account for fluid dynamics.
• Accurate simulation of blood flow is critical for MRgFUS applications.

Purpose of the Study:

• To develop a simple agar-silica flow phantom for MRgFUS preclinical research.
• To investigate the impact of flow dynamics on thermal deposition in MRgFUS.

Main Methods:

• Designed a compact, MR-compatible phantom with 0.8-mm channels for water circulation.
• Performed MR-guided Focused Ultrasound (MRgFUS) sonications on the phantom.
• Utilized real-time MR thermometry at 3T to monitor temperature changes.

Main Results:

• The flow phantom successfully integrated with MR imaging and thermometry.
• Heating patterns differed significantly between static and flowing conditions.
• Flow caused a proximal shift in the focal point and increased near-field heating.

Conclusions:

• The agar-silica flow phantom shows promise for MRgFUS preclinical studies.
• Further research is needed to fully evaluate its simulation capabilities for small vessels.
• Flow dynamics significantly alter thermal deposition in MRgFUS applications.