Foreign experience and also an introduction to ultrasound theory applied on the Biomedical Engineering field.

1. BRUNO OTILIO
Ciência sem Fronteiras
Internship at Mayo Clinic

2. INTRODUCTION
Places that I lived on
Bloomington, IN
Brookings, SD
Rochester, MN
A brief definition on Ultrasound
What is that?
Internship
Mayo Clinic
Elastography
My fronts

3. BLOOMINGTON, IN
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6. There were squirrels on everywhere!!
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7. BROOKINGS, SD
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14. ROCHESTER, MN
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16. “THE FUN TIME FINISHED AND THE WORK
TIME HAS BEGUN”
Stewie Griffin - Family Guy
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17. ULTRA-WHAT?
What is a sound?
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18. SOUND
[1] - http://healthstoriesforkids.com/the-journey-of-ear-infections/
[2] - http://hyperphysics.phy-astr.gsu.edu/hbase/sound/tralon.html
[1]
[2]
Mechanical Electric
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19. What frequency can humans hear? -> 20Hz - 20kHz
[3] - http://healingsounds.co.za/content/about-sound-1
[3]
Ultrasound = f>20kHz
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20. IF HUMANS CANNOT HEAR IT… WHY IS THAT IMPORTANT?
[4] - http://www.raymarine.com/view/?id=3173
History:
– First practical application, 1912 unsuccessful search
for Titanic
– WWII brought massive military research-SONAR
(SOund Navigation And Ranging) -> SONAR
– Mid-century used for non-destructive testing of
materials
– First used as diagnostic tool in 1942 for localizing
brain tumors
– 1950’s 2D gray scale images
– 1965 real-time imaging
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21. SONOGRAPHY ULTRASOUND IMAGING
➤It uses high-frequency sound waves to view inside
the body.
➤They can also show movement of the body's
internal organs as well as blood flowing through
the blood vessels.
➤Unlike X-ray imaging, there is no ionizing
radiation exposure associated with ultrasound
imaging.
➤A transducer is placed directly on the skin or inside
a body opening.
➤ Gel is applied to the skin so that the ultrasound
waves are transmitted from the transducer through
the gel into the body.
➤The ultrasound image is produced based on the
reflection of the waves off of the body structures.
➤The strength (amplitude) of the sound signal and
the time it takes for the wave to travel through the
body provide the information necessary to produce
an image.http://www.medicalnewstoday.com/articles/245491.php?page=2
http://www.fda.gov/Radiation-EmittingProducts/RadiationEmittingProductsandProcedures/MedicalImaging/ucm115357.htm
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22. HOW IS ULTRASOUND CREATED?
GE LogiQ 7 Transducers
http://www.vaultrasound.com/educational-resources/ultrasound-physics/transducers/
Verasonics
In medicine, ultrasound (f > 1 MHz) is used to detect changes in
appearance, size or contour of organs, tissues, and vessels or detect
abnormal masses, such as tumors.
Radiologyinfo.org
(typically 20–600 V at 1 kHz).
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23. TRANSDUCERS AND IMAGING
➤ Transducer element: > 256
elements measuring 1mm X 10
mm each.
➤ Real-Time US -> 16 frames/sec
must be displayed.
➤ Doppler Ultrasound: Doppler
ultrasound, a special application
of ultrasound, measures the
direction and speed of blood cells
as they move through vessels.
Acoustic waves’ velocity depends of the medium.
http://ultrasound-scanner.com/5-2-color-doppler-ultrasound-system.html
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24. ULTRASOUND QUANTITIES AND UNITS
➤ Frequency: The range of 2 - 10
MHz.
➤ Propagation Speed: Typically, 1540
m/sec for soft tissue.
➤ Pulsed ultrasound: To achieve the
depth of resolution (milliseconds)
➤ US interaction with tissue:
Attenuation
➤ Angle of Incidence (Snell’s law)
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Gel is important for that!!
Transducer
High frequency Low frequency
better resolution weak resolution
attenuation attenuation

25. REFERENCES
➤ John E. Aldrich, PhD. Basic physics of ultrasound imaging
➤ Jens E. Wilhjelm, Andreas Illum, Martin Kristensson and Ole Trier Andersen. Medical diagnostic
ultrasound - physical principles and imaging. Biomedical Engineering, DTU Elektro Technical
University of Denmark
➤ P N T Wells. Ultrasonic imaging of the human body. Department of Medical Physics and
Bioengineering and Centre for Physics and Engineering Research in Medicine, Bristol General
Hospital, Bristol BS1 6SY, UK.
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