Jun 27 – 29, 2022
National Physical Laboratory
Europe/London timezone

Acoustic propagation in weakly nonlinear regime using ray tracing approximation with applications in HIFU

Jun 29, 2022, 3:20 PM
20m
Auditorium, First Floor, Module 16 (National Physical Laboratory)

Auditorium, First Floor, Module 16

National Physical Laboratory

National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, United Kingdom

Speaker

Matt Foster (UCL)

Description

High Intensity Focused Ultrasound (HIFU) is a therapy that uses ultrasound waves to non-
invasively destroy malignant cells inside the human body. The technique works by sending a
high-energy beam of ultrasound into the tissue using a focused transducer. Numerically mod-
elling HIFU presents a problem due to nonlinear effects leading to the formation of harmonics
of the source frequency. Each significant harmonic requires a finer grid to resolve, rapidly
increasing computational complexity. We look to use the weakly non-linear ray theory frame-
work to reduce the nonlinear PDE in Rd to a set of one dimensional PDEs. We construct rays
emanating from the transducer on which we calculate the phase of the waves via the Eikonal
equation. In ray coordinates the amplitude can be found by solving the nonlinear transport
equation along the ray. This equation can be transformed into the Burger’s equation which
we then solve and transform back to obtain the amplitude along each ray.

Preferred Contribution Type Presentation

Primary authors

Matt Foster (UCL) Marta Betcke (University College University) Ben Cox (University College London) Bradley Treeby (University College London)

Presentation materials

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