HIFU beam

HIFU beam models nonlinear axially symmetric focused ultrasound beams and shock-front formation to simulate high-intensity focused ultrasound (HIFU) fields for research and therapeutic transducer and exposure protocol design.

Key Features:

• Nonlinear axially symmetric beam modeling: Models formation of shock fronts in axially symmetric focused ultrasound beams for high-amplitude HIFU fields.
• Evolution-type equations: Implements the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation and the one-way Westervelt equation for beam propagation.
• Shock-capturing methods: Uses shock-capturing numerical methods to simulate strongly nonlinear acoustic fields with high-amplitude shocks.
• Acoustic absorption models: Supports thermoviscous and power-law acoustic absorption for biological tissue simulations.
• Media support: Handles radially symmetric beams in homogeneous and layered media.
• Source and array simulation: Simulates fields from single-element transducers and annular arrays with parameterized frequency, diameter, and radius of curvature.
• Multi-language implementation: Combines a MATLAB toolbox with a binary executable compiled from FORTRAN source code.

Scientific Applications:

• Shock-based HIFU: Simulation of shock-based high-intensity focused ultrasound exposures for therapeutic applications.
• Boiling histotripsy: Modeling of boiling histotripsy exposures involving strong nonlinear and thermal effects.
• Drug delivery and immunotherapy: Simulation support for ultrasound-mediated drug delivery and immunotherapy protocols.
• Transducer design and characterization: Design and characterization of high-power ultrasound transducers and annular arrays.
• Exposure protocol development: Evaluation of linear, quasi-linear, and shock-wave exposure protocols.
• Representative simulations: Single-element source in water (1 MHz, 100 mm diameter, 90 mm radius of curvature); 16-element annular array in water (3 MHz, 48 mm diameter, 35 mm radius of curvature); layered "water-muscle-kidney" medium with an abdominal-type source (1.2 MHz, 120 mm diameter and radius of curvature).

Methodology:

Computational methods include evolution-type equations (KZK and one-way Westervelt) for radially symmetric beams, thermoviscous or power-law acoustic absorption models, and shock-capturing numerical methods applicable in homogeneous and layered media.