Investigation of feasibility of noise suppression method for cavitation-enhanced high-intensity focused ultrasound treatment

Ryo Takagi, Yoshihiko Koseki, Shin Yoshizawa, Shin ichiro Umemura

Research output: Contribution to journalArticlepeer-review

Abstract

In high-intensity focused ultrasound (HIFU) treatment, a method that monitors tissue changes while irradiating therapeutic ultrasound is needed to detect changes in the order of milliseconds due to thermal coagulation and the presence of cavitation bubbles. The new filtering method in which only the HIFU noise was reduced while the tissue signals remained intact was proposed in the conventional HIFU exposure in our preliminary study. However, HIFU was irradiated perpendicular to the direction of the imaging ultrasound in the preliminary experiment, which was believed to be impractical. This study investigated the efficacy of the proposed method a parallel setup, in which both HIFU and imaging beams have the same axis just as in a practical application. In addition, this filtering algorithm was applied to the “Trigger HIFU” sequence in which ultrasound-induced cavitation bubbles were generated in the HIFU focal region to enhance heating. In this setup and sequence, HIFU noise level was increased and the summation or difference tone induced by the interaction of HIFU waves with the imaging pulse has the potential to affect this proposed method. Ex-vivo experiments proved that the HIFU noise was selectively eliminated by the proposed filtering method in which chaotic acoustic signals were emitted by the cavitation bubbles at the HIFU focus. These results suggest that the proposed method was practically efficient for monitoring tissue changes in HIFU-induced cavitation bubbles.

Original languageEnglish
Article number106394
JournalUltrasonics
Volume114
DOIs
Publication statusPublished - 2021 Jul

Keywords

  • Cavitation
  • High-intensity focused ultrasound
  • Noise suppression
  • Ultrasound imaging

ASJC Scopus subject areas

  • Acoustics and Ultrasonics

Fingerprint Dive into the research topics of 'Investigation of feasibility of noise suppression method for cavitation-enhanced high-intensity focused ultrasound treatment'. Together they form a unique fingerprint.

Cite this