Feasibility of an electromagnetic compatibility method for MRgFUS using a wire mesh screen

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Acoustic Physics

Background:

• High-intensity focused ultrasound (HIFU) surgery requires integration with magnetic resonance (MR) imaging.
• Electromagnetic interference between HIFU and MR systems can degrade image quality and treatment accuracy.
• Existing shielding methods may impede acoustic transmission or require complex phase correction.

Purpose of the Study:

• To evaluate a novel conductive wire mesh screen for electromagnetic compatibility in MR-guided HIFU surgery.
• To assess the screen's impact on ultrasound transmission, acoustic field, and MR image quality.
• To develop and validate a hybrid acoustic simulation method for analyzing mesh parameters.

Main Methods:

• A conductive wire mesh screen was designed and implemented for shielding electromagnetic radiation.
• A hybrid acoustic simulation method was used to analyze the effects of mesh parameters and HIFU frequency.
• Experiments measured acoustic pressure profiles and radiated electromagnetic noise.
• MR image quality was assessed with the shielding method in place.

Main Results:

• The mesh screen demonstrated good ultrasound transmission and shielding effectiveness.
• Electromagnetic radiation emission was reduced by 14dB at 128MHz.
• Acoustic focal intensity was reduced by less than 11% with a single screen.
• MR image quality was improved without requiring additional phase correction.

Conclusions:

• The proposed conductive wire mesh screen offers an effective and simple solution for electromagnetic compatibility in MR-guided HIFU.
• This method successfully reduces electromagnetic interference, preserves acoustic focal intensity, and enhances MR image quality.
• The findings support the practical implementation of this shielding technique in focused ultrasound surgery.