PRELIM EXAM (All TOPICS) Flashcards
Italian Biologist, Priest and Professor
(1729-1799)
LAZZARD SPALANZANI
FATHER OF ULTRASOUND
LAZZARD SPALANZANI
“He researched bats and found that they rely on sound, rather than sight, for navigation.”
LAZZARD SPALANZANI
LAZZARD SPALANZANI
Echolocation
They first demonstrated Piezoelectricity.
PIERRE AND JACQUES CURIE
Ability to create __________ ______ with the discovery of Piezoelectricity
Ultrasound waves
Piezoelectricity effect:
Soundwaves striking a piezoelectricity material, automatically produces an ________ ______
Electric signal
Piezoelectricity Effect:
“The HARDER you push, the _________ the __________”
The harder you push, the bigger the voltage.
Piezoelectric comes from a greek word “_____”
PIEZEIN
GREEK TERM OF PIEZO
PUSH
Greek word ‘piezein’ means
TO PRESS / TO SQUEEZE
Greek word ‘piezein’ means
TO PRESS / TO SQUEEZE
Echolocation
Lazzard Spalanzani
Austrian Physicist
Christian Johann Doppler
He investigates the phenomenon in which the pitch of a sound varies when the source of the sound is in motion.
Christian Johann Doppler
Christian Johann Doppler is known for his principle which is the :
THE DOPPLER EFFECT
Principle:
The frequency of source is due to the relative motion between the SOURCE and OBSERVER
THE DOPPLER EFFECT
Who invented the first TRANSDUCER?
PAUL LANGEVIN
Paul Langevin invented the _____ _________ to detect submarine and iceberg during WWI
First Transducer
The sinking of TITANIC (1912) inspires him and Constantin Chilowsky to invent ________ __________ (__________) to detect icebergs
Ultrasound Machine (HYDROPHONE)
NEUROLOGIST
Karl Dussik
He was the pioneer in using ultrasound for medical diagnosis.
Karl Dussik
Tried to outline the ventricles of the brain using ______________, a principle similar to x-ray
imaging.
echo-transmission
He Tried to outline the ventricles of the brain using echo- transmission, a principle similar to x-ray
imaging.
Karl Dussik
Swedish Cardiologist
Dr. Inge Edler
Who is the father of Echocardiography?
DR. INGE EDLER
List the Importance of Ultrasound in Diagnosis of Diseases
• To view the uterus and ovaries during pregnancy
• Diagnose gallbladder disease
• Evaluate blood flow
• Guide a needle for biopsy or tumor treatment
• Examine a breast lump
• Check the thyroid gland
• Find genital and prostate problems
• Assess joint inflammation (synovitis)
• Evaluate metabolic bone disease
Advantages of Diagnostic Ultrasound
• NONINVASIVE
• LESS RISK
• WIDELY ACCESSIBLE
• VERSATILE IMAGING
Limitations of Diagnostic Ultrasound
• Soundwaves dont travel well through air or bone
• Body habitus
• Ultrasound may also be unable to see the objects located very deep in the human body
It describes the possible harmful effects that the imaging technique may have on human tissue.
Biological Effects of Ultrasound
What are the two biological effects of Ultrasound?
• Thermal
• Mechanical
____________ has a remarkable record for patient safety with no significant adverse bio effects reported in the literature
ULTRASOUND
Ultrasound produces biological effects by two tissue interactions:
• HEATING
• CAVITATION
It is caused by the mechanical friction of tissues moving as ultrasonic waves pass through them.
HEATING
It involves the formation and collapse of tiny bubbles within the fluid between and inside cells.
CAVITATION
It leads to mechanical damage and can also produce free radicals and other chemicals that may harm cell DNA.
ULTRASONIC CAVITATION
Due to the law of the conservation of energy, all of the sound energy attenuated by tissues must be converted to other forms of energy. The majority of this is turned into heat.
THERMAL EFFECTS
It states that energy can neither be created nor destroyed - only converted from one form of energy to another.
The Law of the Conservation of Energy
It refers to damage caused by the actual oscillation of the sound wave on tissue.
MECHANICAL EFFECTS
WHAT ARE THE PARAMETERS OF SOUNDWAVES
• Power
• Period
• Amplitude
• Frequency
• Intensity
• Wavelength
• Speed / Velocity
The capacity of a material to produce an electric charge when subjected to mechanical stress.
Piezoelectric Effects
What is the unit of frequency?
Hertz (Hz)
Measurement of speed?
Meter per second (m/s)
It is determined by the density and stiffness of the tissue, rather than by characteristics of the sound waves themselves
Velocity
Number of cycles of an acoustic variable that occur in one second
Frequency
1 Hertz (Hz) is equal to……
1 cycle
The difference between the average value and maximum value of an acoustic variable. (Pa, mm, cm, or g/cm3)
Amplitude
Height of the waves
Amplitude
What are the units of Amplitude?
Pa, mm, cm, g/cm3, dB
The rate of energy transfer
Power
Power ______ as sound propagates through the body
decreases
The time required to complete a single cycle
Period
what ate the units of Period?
s, ms, μs
The distance of a complete cycle
WAVELENGTH
Short wavelength =
High frequency
Low Frequency =
Long wavelength
The power delivered over a specific area
Intensity
Units of Intensity
watts/cm2 or milliwatts/cm2
The rate at which waves pass through a medium.
Speed
SOUNDWAVES SPEED FROM FASTEST TO SLOWEST
• Solid
• Liquid
• Gases
It has a greater effect on the propagation speed of the wave than density
Stiffness
Sitffness ⬆️ =
Speed ⬆️
DENSITY ⬆️
SPEED ⬇️
Propagation speed of Air
330 m/s
Propagation speed of H20
1430 m/s
PROPAGATION SPEED OF FAT
1450 m/s
PROPAGATION SPEED OF SOFT TISSUE
1540 m/s
PROPAGATION SPEED OF BLOOD
1570 m/s
PROPAGATION SPEED OF MUSCLE
1585 m/s
PROPAGATION SPEED OF BONE
4080 m/s
What is in below 20Hz?
Earthquake (Infrasound)
What Hz is Low Bass Notes (Accoustic) Human Hearing?
Above 20Hz
What is in 200Hz?
Animal Hearing, Medical Therapy, Ultrasound
What is in 2mHz
NDI and Medical Diagnostics
200mHz:
Acoustic Microscopy
Is audible sound can be heard by human?
Yes
Is ultrasound can be heard by human?
No, the frequency is too high
is infrasound can be heard by human?
no, the frequency is too low
