1. Determining Effects of
Temperature on Tissue Using
High-Frequency Ultrasound:
Porcine Heart (Aorta)
DAVID S. STROUD, CHAD HASKEL, AMY FAIRBROTHER, DAVID
GARCIA, AND TIMOTHY E. DOYLE
UTAH VALLEY UNIVERSITY, OREM, UTAH
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2. Objectives
 Need: Real-time method to
determine tumor extent in margins
 Application: Breast cancer
 Excised margins change temperature
 37° C (98.6° F) to 15° C (59.0° F)
 Are HF ultrasonic measurements
sensitive to temperature?
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3. Peak Density 3
Peak density from spectraUltrasonic spectra
Lumpectomy
margin

4. Possible Factors Affecting
Measurements
 Sample thickness
(attenuation)
 Temperature
 Surface smoothness
 Microbubbles in couplant
 Transducer pressure on
sample
 Foreign inclusions in
sample (wires, sutures)
 Electronic noise
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5. Methods
 7-150 MHz
 Pitch-catch measurements
 50-MHz immersion transducers, 6-mm dia. elements
 Water bath to vary tissue temperature
 Porcine heart (aorta) and bovine muscle
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6. Results
 Peak density values of porcine specimens show no correlation
to temperature
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7. Results
 Peak density values of bovine specimens also show no
significant correlation to temperature
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8. Results
 Wavespeed values of porcine specimens show no significant
correlation to temperature
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9. Results
 Wavespeed values of bovine specimens also show no
correlation to temperature
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10. Discussion
 Both porcine and bovine data concur
 No correlation between peak density and
temperature
 Intuitive: Scattering should be temperature
independent
 No correlation between wavespeed and
temperature
 Counterintuitive: Wavespeed is a function of
temperature in most fluids and materials
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11. Summary
 Porcine and bovine data agree
 Peak density and wavespeed are not
temperature dependent
 Temperature is not a critical factor in HF
ultrasonic measurements of margin specimens
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