The effect of temperature and viscoelasticity on cavitation dynamics during ultrasonic ablation
Journal
Journal of the Acoustical Society of America
Journal Volume
130
Journal Issue
5
Pages
3458-3466
Date Issued
2011
Author(s)
Abstract
Inertial cavitation has been shown to enhance heating rates during high intensity focused ultrasound treatments. Cavitation dynamics will be affected by heating and by the changes in mechanical properties of tissue resultant from thermal denaturation; however, the nature of the change is not known and forms the focus of the current study. A Keller-Miksis equation is used to find the variation in inertial cavitation threshold with temperature in water and, when coupled with a Kelvin-Voigt viscoelastic model, in biological tissue. Simulated thermal ablation treatments in liver and muscle are used to explore the changes in cavitation dynamics, and the resultant frequency spectra of secondary acoustic emissions, due to tissue denaturation. Results indicate that viscosity is the key parameter controlling cavitation dynamics in biological tissues. The increase in viscosity during denaturation is predicted to increase inertial cavitation thresholds, leading to a substantial decrease in the higher harmonic content of the emitted pressure signal across a wide range of bubble radii. Experimental validation of these observations could offer improved methods to monitor therapeutic ultrasound treatments. ? 2011 Acoustical Society of America.
Subjects
Biological tissues
Bubble radius
Effect of temperature
Experimental validations
Frequency spectra
High intensity focused ultrasound
Higher harmonics
Improved methods
Inertial cavitation
Inertial cavitation threshold
Kelvin-Voigt
Key parameters
Pressure signal
Therapeutic ultrasound
Thermal ablation
Thermal denaturations
Viscoelastic models
Ablation
Biomechanics
Bubbles (in fluids)
Denaturation
Dynamics
Pyrolysis
Spectroscopy
Tissue
Ultrasonic testing
Ultrasonics
Viscoelasticity
Viscosity
Cavitation
water
animal
article
biomechanics
elasticity
flow kinetics
Fourier analysis
gas
high intensity focused ultrasound
human
liver
mechanical stress
motion
necrosis
particle size
pathology
pressure
skeletal muscle
surface tension
temperature
theoretical model
time
viscosity
Animals
Elasticity
Fourier Analysis
Gases
High-Intensity Focused Ultrasound Ablation
Humans
Liver
Models, Theoretical
Motion
Muscle, Skeletal
Necrosis
Particle Size
Pressure
Rheology
Stress, Mechanical
Surface Tension
Temperature
Time Factors
Water
SDGs
Type
journal article