Aberration correction by nonlinear beam mixing: Generation of a pseudo point sound source

Jongbum Seo, J. J. Choi, J. Brian Fowlkes, Matthew O'Donnell, Charles A. Cain

Research output: Contribution to journalArticle

Abstract

Nonlinear beam mixing with microbubbles was explored to create a pseudo point source for aberration correction of therapeutic ultrasound. A damping coefficient for a bubble driven by a dual frequency sound field was derived by revisiting Prosperetti's linearized damping model. As a result, the overall damping term for dual frequency was obtained by linear summation of two damping terms for each frequency. The numerical simulation based on the bubble model suggests that the most efficient size range to generate a 1 MHz frequency from 4 MHz and 5 MHz sound sources is 2.6 to 3.0 μm. Furthermore, this size range constitutes the primary distribution of a specific ultrasound contrast agent. When a chamber of 0.1% of the diluted agent is sonified by 4 MHz and 5 MHz sound beams with 80° incident angle between them, an approximately 100 Pa, 1 MHz difference frequency signal can be measured approximately 10 cm away. In addition, the received 1 MHz difference frequency signal shows omni-directional characteristics, even though the overlap zone of the two sound beams is on the order of the difference frequency wavelength. Therefore, the induced sound source can be considered as a pseudo point source and is expected to be useful for aberration correction for therapeutic ultrasound.

Original languageEnglish
Pages (from-to)1970-1980
Number of pages11
JournalIEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Volume52
Issue number11
DOIs
Publication statusPublished - 2005 Nov 1

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Instrumentation
  • Acoustics and Ultrasonics
  • Electrical and Electronic Engineering

Cite this