SPI exam

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What component of a transducer changes electrical to mechanical and mechanical back to electrical energy?

PZT

An US wave travels through two media and has attenuation of 3dB in the first and 5 dB in the second. What is the total attenuation? a. 15 dB b. 8 dB C. 3/5 dB d. 5/8 dB

B

At the focus, the beam diameter is ___ the transducer diameter. a. equal to b. half C. double d. one-fourth

B

What measures the output of a transducer? a. receiver b. display c. hydrometer d. hydrophone

D

When the sound source and the receiver are not moving directly towards or away from each other, the ____ of the angle between them enters into the calculation of Doppler shift. a. average b. slope c. sine d. cosine

D

Which of the following is associated with cavitation? a. thermal index b. Snell's Law c. Avagadro's Number d. mechanical index

D

If a 5MHZ sound wave is traveling in the tissues listed below, which will have the longest wavelength? a. Fat b. Air C. Muscle d. Bone

d

If wave's amplitude is doubled, what happens to the power? a. nothing b. halved C. doubled d. quadrupled

d

The production of a voltage from the application of a pressure is called a. piezoelectricity b. impedance c. cogeneration d. flux

A

All of the following will improve temporal res EXCEPT: A. Increased line density B. Single rather than multi focus C. Higher frame rate D. Shallower deprh of view E. Slower speed of sound in a medium

A

An ultrasound system is set at 0 dB and is transmitting at full intensity. What is the output power when the system is transmitting at 50%. of full intensity? a. -3 dB b. -50 dB C. 10 dB d. 3 dB e. -10 dB

A

From a safety standpoint, which one of the following methods is best? a. low transmit output ànd high receiver gain b. high transmit output and low receiver gain c. high near gain and low far gain d. low near gain and high far gain e. high reject and high transmitter output

A

If the frequency is decreased, the numerical value of the radial resolution is a. increased b. decreased C. unchanged

A

If the intensity is increased by 3dB, it: a. doubles b. triples c. halved d. quartered

A

If the spatial pulse length is 10 mm, what is the axial resolution? a. 0.5 cm b. 5 cm C. 10 mmn d. 1 cm

A

If the transducer aperture increases, the lateral resolution at its smallest dimension is: a. increased b. decreased C. unchanged

A

If we increase the frequency. the near zone length is: a. Increased b. decreased c. unchanged

A

If wires in an AIUM test object do not appear in the same place as on the display, what is amiss? a. registration accuracy b. dynamic range accuracy c. near gain d. gray scale dynamic range

A

In a real time scanner, which of these choices determines the maximum frame rate? A. depth of view b. pixel size c. attenuation coefficient d. beam diameter e. lateral resolution

A

In soft tissue: Distance traveled = ___ x round trip time a. propagation speed b. wavelength c. period d. PRF

A

The angle of incidence of an US beam is perpendicular to an interface. The two media have the same propagation speeds. What process cannot occur? a. refraction b. reflection C. transmission d. attenuation

A

The dynamic range is the ratio of the smallest to the largest ____ that a system can process without distortion. a. amplitude b. frequency c. phase delay d. spatial length

A

The interaction of microscopic bubbles and ultrasound form the basis for cavitation bioeffects. Which of the following forms of cavitation are most likely to produce microstreaming in the intracellular fluid and shear stresses? a. stable cavitation b. normal cavitation C. transient cavitation d. inertial cavitation e. active cavitation

A

Traveling through the same mediurn, if the frequency is doubled, the propagation speed is: a. unchanged b. doubled C. halved d. quartered

A

What are typical clinical Doppler frequencies? a. 1-10,000HZ 1-10.000HZ b. 1-10мн2 c. 2-1,000kHz d. 40-45KHZ

A

What is the fraction of time that a transducer is transmitting? a. duty factor b. pulse duration c. period d. PRF spatial duration

A

What is the production of deformation from voltage called? a. piezoelectricity b. impedance c. cogeneration d. flux

A

What is the significance of gray scale variation in the spectrum of a pulsed wave Doppler display? a. it represents the number of red blood cells creating the reflection b. it represents the velocity of red blood cells c. it represents the speed of red blood cells d. it represents the convergence of red blood cell lamina e. it determines the ensemble length

A

What may be a unit of amplitude? a cm b. Hz C. msec d. watts e. none of the above

A

When can a patient revoke consent? a. at any time b. before the procedure begins C. never d. only prior to sedation

A

Which of the following best describes the empirical approach to the study of bioeffects? a. exposure-response b. cause-effect C. risk-benefit d. causation-reaction e. effect-microstreaming

A

Which of the following best describes the mechanistic approach to the study of bioeffects? a. cause-effect b. exposure-response C. risk-benefit d. causation-reaction e. effect-microstreaming

A

Which of the following choices determines the signal amplitude in the transducer of an ultrasound system? a. reflected intensity of the sound beam b. post processing C. edge enhancement filtering d. persistence e demodulation

A

Which of the following does not change temporal resolution? a. frequency compounding b. persistence C. spatial compounding d. temporal resolution

A

Which of the following has the greatest influence on temporal resolution? a. propagation speed and the imaging depth b. frequency of sound and the propagation speed C. wavelength of sound & propagation speed d. output power & frequency

A

With the presence of ____ we see more boundaries than there are reflecting surfaces. a. reverberations b. shadowing c. enhancement d. arrays

A

What is another name for longitudinal resolution? a axial b. depth c. lateral d. transverse

A & B

If we increase the transducer diameter, the beam diameter in the far zone is: a. increased b. decreased c. unchanged

B

Miltiple reflections that are equally spaced are called: A. Refractions B. Reverberations C. Shadows D. Comets

B

The Doppler shift is the ____ of two frequencies. a. sum b. difference C. product d. ratio

B

The Fresnel is the: a. focus b. near zone C. far zone d. penetration depth

B

The more pixels per inch: a. the better the temporal resolution b. the better is the spatial resolution c. the more shades of gray d. the higher the reliability

B

The region from the trans- /ducer to the minimum beam cross-sectional area is the a. Fraunhofer zone b.Fresnel zone c. focus d. Snell's length

B

What determines the frequency of a sound beam from a pulsed transducer? a. voltage applied to the PZT b. PZT thickness C. frequency of the system d. PRF of the pulser

B

While propagating, sound wave is refracted. Finally, it returns to the transducer. The system processes the sound wave as if it has: a. refracted and returned b. traveled in a straight line, reflected & returned C. traveled in a straight line, attenuated, reflected & returned

B

temporal resolution Which of the following is not preprocessing? a. write magnification b. 3-D rendering C. fill-in interpolation d. spatial compounding

B

A quality assurance program: a. is not needed in small labs b. is very time consuming and expensive c.is needed by all labs d. cannot be performed by sonographers

C

According to the AIUM statement on bioeffects, there have been no confirmed bioeffects below intensities of ___ watts per square centimeter SPTA. a. 10 b. 0.01 c. 0.1 d. 1 e. 100

C

Assuming a constant frequency, what happens if the diameter of an unfocused circular transducer is increased? a. the distance to the far field is reduced b. the beam width in the near field is reduced c. the beam width in the near field is increased d. the US wavelength is increased e. the sensitivity is reduced

C

Changing which of the following would not cause any change in a hard copy image output? a. TGC b. overall gain c. output power D. display brightness & contrast e. depth of view

C

Enhancement, multipath and side lobes result in: a. image distortion b. clearer images c. artifact d. resolution problems

C

How many bits are necded to represent 1024 gray shades? a. 1024 b. 8 c. 10 d. 3 e. 512

C

How many data bits are needed to represent 46 gray shades? a. 46 b. 5 c. 6 d. 8

C

If a manufacturer changed the lines per frame and kept the imaging depth the same, what else would change? a. PRF b. period c. frame rate

C

If the lines per frame is increased while the imaging depth is unchanged then: a. frame rate increases b. number of shades of gray decreases c. the frame rate decreases d. this cannot happen

C

Lateral resolution can be improved by: a. increasing gain b. decreasing gain c. focusing d. smoothing

C

Put in increasing order of propagation speed: a, air, bone, water b. bone, water, air c. air, water, bone d. water, air, bone e. bone, air, water

C

The more bits per pixel: a. the better the resolution b. the higher the pixel density c. The more shades of gray d. higher reliability

C

The range equation relates distance from the reflector to ___ and ___. a. time-of-flight, distance b. frequency, wavelength c. time-of-flight, propagation speed d. propagation speed, density

C

Traveling through the same medium, if the frequency is doubled, the wavelength is a. unchanged b. doubled C.halved d. quartered

C

Volume has which of the following units? а. cm b. cm2 c. cm3 d. cm4

C

What is the Fraunhofer? a. focus b. near zone C. far zone d. penetration depth

C

What is the elimination of voltages that do not exceed a certain level? a. amplification b. decompensation c. reject d. demodulation

C

What is the most typical Doppler shift measured clinically? а. 3.5МHZ b. 3,500,000HZ c. 2kHz d. 1,000kHz e. 20,000HZ

C

What would be the brightest B-mode spot when scanning the following?

C

Which is not a part of a transducer? a. active crystal b. matching layer c. A/D converter d. wire

C

Which of the following is proportional to the square of the amplitude? a. period b. attenuation c. power d. frequency e. speed

C

Which of the following is the best lateral resolution? a. 15 mm b. 6 mm c. 0.06 cm d. 2 cm

C

Which type of artifact appears most commonly with highly reflective objects? a. reverberations b. mirroring c. shadowing d. enhancement e. defocusing

C

d. The propagation speed of US in the AIUM test object is: a. 1m/s b. 1.54 m/s c. 1.54 mm/us d. 1 km/s

C

What is the name of the receiver function that corrects for attenuation?

Compensation

The process of reducing the difference between the smallest and largest voltages is called:

Compression

A transducer ____ one form of _____ into another.

Converts, energy

A Doppler exam is performed with a 5 MHz probe and a PRF of 15 kHz. Which of these Doppler shifts will create aliasing? a. 2 kHz b. 2.5 kHz C. 7.5 kHz D. 14 kHz

D

Attenuation of US in soft tissue is closest to: a. 3 dB/1MHZ b. 1 dB/cm/10MHZ C. 2 dB/cm d. 0.6 dB/cm/MHz

D

Fill-in of an anechoic structure such as a cyst is known as all of the following EXCEPT? a. partial volume artifact b. slice thickness artifact c. section thickness artifact d. ghosting artifact

D

In an air-tissue interface, what percentage of the US is reflected? a. 0% b. near 0% C. 50% d. near 100%

D

Rectification and smoothing are components of which of the following? a. amplification b. decompensation C. reject d. demodulation

D

The dB is defined as the of two intensities. a. sum b. difference C. product d. ratio

D

The distance to a target is doubled. The time-of-flight for a pulse to travel to the target and back is: a. 4 times b. 8 times c. the same d. 2 times

D

The impedance of tissue is 3 x 10^5 rayls and for the PZT crystal is 6 x 10^6 rayls. What is the best impedance for the matching layer? a. 36 x 10^6 b. 3,600 C. 10,000 d 9.5 x 10^5 e. 9 x 10^4

D

What Doppler angle is most. inaccurate? a. 15-30 degrees b. 30-45 degrees C. 45-60 degrees d. 60-75 degrees

D

What are the units of longitudinal resolution? a. Hertz b. Rayls c. m/s d. feet

D

What artifact has a grainy appearance and is caused by the interferenfe effects of scattered sound? A. Spakle B. Reverberation C. Slice thickness D. Spekle E. Section thickness

D

What can pulsed Doppler measure that continuous wave cannot? a. duration b. speed C. velocity d. location e. frequency

D

What component of the US unit contains the memory bank? a. transducer b. receiver c. display d. scan converter

D

What is propagation speed determined by? a. wavelength b. intensity & density C. amplitude d. density and elasticity e. density and amplitude

D

What is the actual time that an US machine is creating a pulse? a. duty factor b. period c. pulse period d. pulse duration

D

What is the standard for communication between medical imaging computers? a. ALARA b. PACS c. D-to- A conversion d. DICOM e. A-to-D conversion

D

Impedance is the product of ___ and ____.

Density & propagation speed

An ultrasound system is set at 0 dB and is transmitting at full intensity. What is the output power when the system is transmitting at 10% of full intensity? a. -3 dB b. -50 dB C. 40 dB d. 3 dB e. -10 dB

E

If 300,000 cycles occur in a setond, what is the wave's frequency? a. 3 MHz b. 30 kHz с. 300 МНz d. 3 kHz e. 0.3 MHz

E

The relative output of an US instrument is calibrated in dB and the operator increases the output by 60 dB. The beam intensity is increased by which of the following? a. 5%. b. two times c. twenty times d. one hundred times e. one million times

E

What is the range of frequencies created by medical diagnostic Doppler transducers? a. 4-10HZ b. 10-20MHZ C. 1-10kHz d. 2-20HZ e. 2-10MHZ

E

Which of the following clinical modalities has the lowest output intensity? a. pulsed Doppler b. continuous wave Doppler c. power Doppler d. duplex scanning e. gray scale imaging

E

Which one of the following sets of properties of a test phantom is most relevant when assessing depth calibration accuracy? a. reflector spacing and reflection coefficient b. attenuation and speed of US in the medium c. reflector spacing and US attenuation in the medium d. reflector reflection coefficient and US attenuation in the medium e. reflector spacing and propagation speed

E

(True False)A mirror image artifact can appear along side of the true anatomy.

False

(True or False) A sonographers education ends when they become registered.

False

(True or False) Doppler shifts are always created when the source and receiver are in motion relative to each other.

False

(True or False) The digital scan converter has a number of pixels assigned to each bit.

False

(True or false) Doppler shifts always occur if the source and observer are in motion relative to each other and the angle between the motion and the sound beam is 90°.

False

(True or false) Sonographers cannot affect a patient's exposure to acoustic energy.

False

(True or false) The manufacturer increases the number of lines per frame. As a result, which of the following may have to be decreased? Frequency

False

(True orFalse) Doppler shifts always occur if the source and receiver are in motion relative to each other.

False

True or False Increasing the frequency increases the penetration depth.

False

True or False. Axial resolution is affected by focusing.

False

(True br False) Doppler shifts always occur if the source and observer are in motion relative to each other and the angle between the motion and the sound beam is not 90 degrees.

True

(True or False) Gray scale can be changed by the sonographer.

True

(True or false) The manufacturer increases the number of lines per frame. As a result, which of the following may have to be decreased? Frame rate

True

(True or false) The manufacturer increases the number of lines per frame. As a result, which of the following may have to be decreased? Imaging depth

True

(True or false) The manufacturer increases the number of lines per frame. As a result, which of the following may have to be decreased? Sector angle

True

(True or false) The manufacturer increases the number of lines per frame. As a result, which of the following may have to be decreased? Power output

True

What is the location of the minimum cross-sectional area of the US beam called? a. focus b. Fraunhofer zone c. far zone d. near zone

a

When may a patient revoke their consent to be treated? a. at any time b. when it is safe to terminate the procedure C. never

a

Which of the following has a propagation speed closest to "soft tissue"? a. muscle b. fat C. bone d. air

a

What happens to venous return to the heart during expiration? a. Increased b. Decreased c. Unchanged

b

Biologic effects have not been documented below what intensity (SPTA)? a. 100 W/cm b. 100 mW/m? c. 100 mw/cm2 d. 100 mW/cm3

c

The Curie temperature has which effect? a. the backing material delaminates from the active element b. the glue binding the crystal & matching layer melts c. the ferroelectric material is depolarized d. the matching layer changes its impedance

c

Put in decreasing order: a. deca b. deci C micro d. centi

ABDC

What are attenuation's three components?

Absorption, reflection, & scattering

(True o False) boppler shifts always occur if the sound source and receiver are in motion.

False

(True or False) Lateral resolution is also called: axial

False

(True or False) Lateral resolution is also called: longitudinal

False

(True or False) Lateral resolution is also called: range

False

(True or False) There have not been biolegical effects from US found in the laboratory.

False

(True or False) With normal incidence the angle is 180°.

False

(True or False) With right angle incidence, reflections are always generated at a boundary if the propagation speeds of the media are different.

False

(True or false) The sonographer cannot change, directly or indirectly, the duty factor of an US machine.

False

(True or False) A sound wave ted pressure wave made of compressions and rarefactions.

True

(True or False) A system which was working well now does not display clear images in the far field. This may be a problem with the monitor

True

(True or False) A system which was working well now does not display clear images in the far field. This may be a problem with the receiver

True

(True or False) A system which was working well now does not display clear images in the far field. This may be a problem with the scan converter

True

(True or False) A system which was working well now does not display clear images in the far field. This may be a problem with the transducer

True

(True or False) Lateral resolution is also called: azimuthal

True

(Trug or False) Shadowing may result from high amounts of reflection of US energy.

True

A pulse is emitted by a transducer and is traveling in soft tissue. The go-return time, or time-of-flight, of a sound pulse is 130 microseconds. What is the reflector depth? a. 10 cm b. 10 mm C. 10 m d. 130 mm e. 13 ст

a

A sound wavee frequency is 10 MHz. The wave is traveling in soft tissue. What is its wavelength? a. 0.15 mm b. 1.54 mm C. 15.4 mm d. 0.77 mm e. 10 МHz

a

All of the following are true EXCEPT: a. Two waves with identical frequencies must interfere constructively. b. Constructive interference is associated with waves that are in-phase. C. Out-of-phase waves interfere destructively d. Waves of different frequencies may exhibit both constructive and destructive interference at different times.

a

As the impedances of two media become vastly different, the a. reflection increases b. transmission increases C. refraction increases d. absorption increases

a

Impedance is the _____ of ____ and _____. a product, propagation speed, density b. sum, stiffness, density c. quotient, stiffness, propagation speed d. difference, attenuation, density

a

Sound intensity is decreased by 75%. How many decibels of attenuation is this? a. 6dB b. 9dB C. 5dB d. 10dB

a

The most reflection likely amount of between soft at a boundary tissues is: a.1% b. 22% C. 34% d. 99%

a

The units of pulse repetition frequency are a. per minute b. msec c. mm/us d. MHx

a

Under which of the following conditions is axial resolution improved? a. decreased spatial pulse length b. decreased pulse.amplitude c. decreased imaging depth d. decreased pixel size e. decreased beam diameter

a

What happens to the speed of sound in a medium when the bulk modulus of the medium increases? a. faster b. slower C. unchanged

a

What is the approximate attenuation coefficient of 1 MHz US in soft tissue? a. 0.5dB/cm b. 1cm C. 3dB/cm d. 1dB

a

Which of the following is associated with power mode Doppler? a. poor temporal resolution and flash artifact b. lower sensitivity and good temporal resolution c. high sensitivity and high frame rates d. flash artifact and reduced sensitivity e. good temporal resolution and flash artifact

a

Which of the following sound waves is ultrasonic and least useful in diagnostic imaging? a.30 KHz b. 8 MHz C. 8,000 Hz d. 3.000 kHz e. 15 Hz

a

Which of the following tissues is most likely to create Rayleigh scattering? a. red blood cells b. muscle c. fat d. bone

a

_____ resolution is determined by the spatial pulse length. a. radial b. image c. axial d. angular

a & c

Depth calibration of a machine measures 100mm spaced wires to be 90mm apart. Scanning reflectors 50mm apart, what will the machine calculate the distance to be? a. 40mm B. 45mm C. 60mm d. 65mm

b

How many cm are 60 millimeters? а. 600 b. 6 C. 0.6 d. 0.06

b

If a 5MHZ sound wave is traveling in the tissues listed below, which will have the shortest wavelength? A Fat B. Air C. Muscle d. Bone

b

If a reflector is moved twice as far away from the transducer, how will this affect the time- of-flight of a sound pulse? a. quadruple it b.double it c. no change d. halve it

b

If the frequency of Us is increased from 0.77 MHz to 1.54 MHz, what happens to the wavelength? a. doubles b. halved C. remains the same d. 4times greater

b

If the frequency of an US wave is doubled, what happens to the period? a. doubles b. halved C. remains the same d. 4 times greater

b

Sound is traveling from medium 1 to medium 2. Propagation speeds of M1 and M2 are 1,600m/s and 1,500m/s, respectively. There is normal incidence. a. angle of incidence > angle of reflection b. angle of incidence = angle of reflection c. angle of incidence < angle of reflection

b

The angle between an US pulse and the boundary between two media is 56°. This is called: a. direct incidence b. oblique incidence c. indirect incidence d. orthogonal incidence

b

The time from the beginning of a pulse until its end is a. period b. pulse duration C. pulse length d. PRF

b

What happens to the speed of sound in a medium when the bulk modulus of the medium decreases? a. faster b. slower C. unchanged

b

_____ is the distance covered by one cycle. a. pulse length b. wavelength C. cycle distance d. cycle duration

b

As a result of ____ the propagation speed increases. a. increasing stiffness and increasing density b. increasing stiffness and increasing elasticity c. decreasing compressibility and decreasing density d. decreasing stiffness and decreasing density

c

For soft tissue, the approximate attenuation coefficient in dB/cm is equal to one-half _____ in _____. a. wavelength, mm b. frequency, Hz c. frequency, MHz d. impedance, rayls

c

If the frequency of US is increased from 0.77 MHz to 1.54 MHz, what happens to the propagation speed? a. doubles b. halved c. Remains the same d. 4 times greater

c

If the intensity of a sound beam remains unchanged while the beam area is reduced in half, what has happened to the power? a. quadrupled b. doubled c. halved d. unchanged

c

Power of sound has units of a. dB b. dB/cm C. watts d. watts/cm2

c

Refraction only occurs if there are: a. normal incidence & different impedances b. indirect intensity & different propagation speeds c. oblique incidence & different propagation speeds d. oblique frequency & identical impedances

c

Snell's law describes physics of a. ultrasound b. reflection c. refraction d. transmission

c

The Doppler shift is a measure of: a. ratio of incident frequency to reflector frequency b. sum of incident frequency & reflected frequency c. difference between incident & reflected frequency d. product of incident and reflected frequencies

c

The duty factor for continuous wave ultrasound is a. 10.0 b. 1% c. 1.0 d. 0.0%

c

The effects of soft tissue on US are called: a. acoustic proliferation properties b. dynamic effects c. acoustic propagation properties d. biologic effects following

c

The fundamental frequency of a transducer is 2.5MHZ. What is the second harmonic frequency? a. 1.25MHZ b. 4.5MHZ c. 5 MHz d. 5cm

c

The speed of US in soft tissue is closest to: a. 1,540km/sec b. 1.54km/msec c. 1,500m/s d. 1.540mm/sec

c

What are the units of intensity? a. watts b. decibels C. watts/cm squared d. decibels

c

What is the frequency of a wave with 1msec period? a. 10,000HZ b. 1,000kHz c. 1kHz d. 1 MHz

c

Which has the correct order? mega-milli-kilo-micro- a. 10^6 10^-6 10^3 10^-3 b. 10^-6 10^6 10^2 10^-3 c. 10^6 10^-3 10^3 10^-6 d. 10^6 10^-6 10^3 10^-4

c

Which of these intensities is smallest? а. SATP b. SPTP c. SATA

c

___ is the time to complete one cycle. a. pulse duration b. pulse period c. period d. duration period

c

_____ is a redirection of US in many directions as a result of a rough boundary between two media. a. refraction b. Rayleigh scattering C. scattering d. reflection

c

Propagation speed= _____ x wavelength a. pulse duration b. period c. number of cycles in the pulse d. frequency

d

Sound waves are: a. Electric b. Mechanical, transverse c. Spectral d. Longitudinal, mechanical

d

The angle between an US pulse and the boundary between two media is 90°. What is this called? a. direct incidence b. oblique incidence c. indirect incidence d. orthogonal incidence

d

The frequency closest to the lower limit of US is: a. 19,000KHZ b. 10,000MHZ C. 20,000msec d. 15,000HZ

d

The most transmission typical amount of at a boundary in biologic media is: a. 1% b. 22% C. 34% D. 99%

d

The rayl is the unit of: a. intensity b. reflectance c. density d. impedance

d

The units of attenuation are ______ : this is a ____ scale. a. mm/cm, parametric b. dB/m, multiplicative c. none, relative d. dB, logarithmic

d

What is the minimum value of the duty factor? а. 10.0 b. 1% C. 1.0 d. 0.0%

d

Which is not an acoustic variable? a. density b. pressure c. distance d.intensity

d

Which of the following is determined by the source and the medium? a. frequency b. period c. propagation speed d. range resolution

d

With normal incidence, what factors affect refraction of US? a. propagation speeds b. frequencies C. attenuation coefficients d. none of the above

d

Put in decreasing order of propagation speed a. gas b. liquid C. solid

CBA


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