Elastic deformation of soft tissue-mimicking materials using a single microbubble and acoustic radiation force
File(s)
Published version
Author(s)
Bezer, James H
Koruk, Hasan
Rowlands, Christopher J
Choi, James J
Type
Journal Article
Abstract
Mechanical effects of microbubbles on tissues are central to many emerging ultrasound applications. Here, we investigated the acoustic radiation force a microbubble exerts on tissue at clinically relevant therapeutic ultrasound parameters. Individual microbubbles administered into a wall-less hydrogel channel (diameter: 25-100 µm, Young's modulus: 2-8.7 kPa) were exposed to an acoustic pulse (centre frequency: 1 MHz, pulse length: 10 ms, peak-rarefactional pressures: 0.6-1.0 MPa). Using high-speed microscopy, each microbubble was tracked as it pushed against the hydrogel wall. We found that a single microbubble can transiently deform a soft tissue-mimicking material by several micrometres, producing tissue loading-unloading curves that were similar to those produced using other indentation-based methods. Indentation depths were linked to gel stiffness. Using a mathematical model fitted to the deformation curves, we estimated the radiation force on each bubble (typically tens of nanonewtons) and the viscosity of the gels. These results provide insight into the forces exerted on tissues during ultrasound therapy and indicate a potential source of bio-effects.
Date Issued
2020-12-01
Date Acceptance
2020-08-10
Citation
Ultrasound in Medicine and Biology, 2020, 46 (12), pp.3327-3338
ISSN
0301-5629
Publisher
Elsevier
Start Page
3327
End Page
3338
Journal / Book Title
Ultrasound in Medicine and Biology
Volume
46
Issue
12
Copyright Statement
©2020 World Federation for Ultrasound in Medicine & Biology. All rights reserved. This article is available open access under a CC-BY License (https://creativecommons.org/licenses/by/4.0/)
License URL
Sponsor
Wellcome Trust
Engineering & Physical Science Research Council (EPSRC)
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/32919812
PII: S0301-5629(20)30379-3
Grant Number
212490/Z/18/Z
EP/S016538/1
Subjects
Acoustic radiation force
Bjerknes force
Cavitation
Drug delivery
Microbubbles
Ultrasound contrast agents
Publication Status
Published
Coverage Spatial
England
Date Publish Online
2020-09-09