Primary Menu

Education, Events, Publication

Funding & Recognition

Characterizing Temperature-Dependent Tissue Properties for Focused Ultrasound Modeling

Year: 2023

Presenter Name: Isaac Doddridge

Additional Presenters:
Caio Farias
High intensity focused ultrasound (HIFU) is a non-invasive, therapeutic technique used to ablate tumors. HIFU uses concentrated ultrasound waves that are absorbed by human tissue, increasing the local temperature and destroying the tissue. A successful HIFU treatment requires a patient-specific treatment plan that is generated before the therapy by clinicians. Computer modeling can assist clinicians by simulating HIFU treatments and predicting treatment outcomes. However, accurate computer simulations are currently limited due to unknown temperature-dependent properties. An assessment of these properties will make treatments safer and more efficacious. Purpose:
Our research aims to experimentally determine temperature-dependent acoustic and thermal properties of porcine muscle tissue for more accurate HIFU simulations. Methods:
Thermal properties we investigate include thermal diffusivity [mm2/s], thermal conductivity [W/mK], and specific heat capacity [J/kgK], Acoustic properties include the attenuation coefficient [np/cm], and tissue speed of sound [m/s]. To determine how each property varies with respect to temperature, tissue samples are immersed and allowed to equilibrate in a temperature-controlled water bath prior to measurements. The insertion-loss through-transmission technique is used to calculate the speed of sound and attenuation. Radiation force balance also calculates the tissue's attenuation coefficient. The thermal properties of each sample are measured with commercially available thermal sensors (METER Group TEMPOS Thermal Property Analyzer and TA Instruments MCDSC) to analyze its change in temperature over time). Preliminary Results:
Both acoustic and thermal properties have shown temperature-dependent variation in pork muscle, which has properties similar to human muscle tissue. We have found that attenuation, speed of sound, and specific heat capacity increase as the temperature increases. Current results with the temperature-dependence of thermal conductivity and diffusivity are inconclusive. Conclusion:
The temperature-dependent thermal and acoustic properties we are measuring have the potential to improve simulations for HIFU treatment plans.
University / Institution: Brigham Young University
Type: Poster
Format: In Person
Presentation #B17
SESSION B (10:45AM-12:15PM)
Area of Research: Engineering
Faculty Mentor: Christopher Dillon