Finals Part 2

Question 1

Under which of the following conditions is lateral resolution improved?

a. decreased beam diameter
b. decreased pulse duration
c. decreased imaging depth
d. decreased pixel size
e. decreased spatial pulse length

Answer 1

a. decreased beam diameter

Question 2

In which way is an annular phase array transducer different than a linear phased array transducer?

a. the linear is steered mechanically
b. the linear can have multiple focal zones
c. the annular can create a sector shaped image
d. the linear has higher pulse repetition frequency
e. the annular is steered mechanically

Answer 2

e. the annular is steered mechanically

Question 3

In which of these biologic tissues will sound waves p r o p a g a t e
most quickly?

a. tendon
b. blood
c. lung
d. fat
e. amniotic fluid

Answer 3

a. tendon

Question 4

Which of the following best describes a sound beam?

a. electrical impulses
b. a collection of mechanical vibrations in the form of compressions and rarefactions
c. a wave that man can hear
d. electromechanical
e. ionic vibrations

Answer 4

a collection of mechanical vibrations in the form of compressions and rarefactions

Question 5

You are performing a quality assurance study on an
ultrasound system using a
tissue equivalent phantom.
You make an adjustment using
a knob on the system console that changes the appearance
of reflector brightness from
fully bright to barely visible. What are you evaluating?

a. resolution
b. dynamic range
c. system sensitivity
d. vertical calibration
e. slice thickness

Answer 5

c. system sensitivity

Question 6

Which of the following best describes the features of a sound wave and medium that determine the speed of sound in the medium?

a. density of the medium and stiffness of the medium
b. density of the medium and power of the sound beam
c. elasticity of the medium and frequency of the sound beam
d. stiffness of the medium and elasticity of the medium
e. pulse repetition period of the sound wave and density
of the medium

Answer 6

density of the medium and stiffness of the medium

Question 7

while scanning in a water tank, what location in a sound beam has the highest intensity?

a. focal point
b. focal zone
c. Fresnel zone
d. Fraunhofer zone
e. half value depth

Answer 7

a. focal point

Question 8

Which of these factors has
the greatest influence on pulse repetition period?

a. display depth
b. thickness of the PZT crystal
c. attenuation of the sound beam
d. impedance of the medium
e. display’s dynamic range

Answer 8

a. display depth

Question 9

Which of the following choices best describes an ideal
epidemiologic bioeffects study?

a. randomized and prospective
b. benefits outweigh the risks
c. retrospective and optimized
d. ideal and non-biased
e, prudent and safe

Answer 9

a. randomized and prospective

Question 10

Which of the following will
result in the highest mechanical index?

a. high frequency and low power
b. high intensity and high frequency
.c low frequency and high signal amplitude
d. low intensity and low frequency

Answer 10

c. low frequency and high signal amplitude

Question 11

Al of the following statements regarding in-vitro bioeffects are true EXCEPT:

a. In vitro bioeffects conclusions are clinically relevant
b. In vitro bioeffects are always real
.c In vitro bioeffects are very important
d. In vitro bioeffects may not
be applicable to clinical settings

Answer 11

a. In vitro bioeffects conclusions are clinically relevant

Question 12

Under which circumstance is
the mechanical index highest?

a. high frequency and low p o w e r
b. high intensity and high frequency
c. low intensity and low frequency
d. low frequency and high signal amplitude

Answer 12

d. low frequency and high signal amplitude

Question 13

Which of the following improves the signal-to-noise ratio?

a. dynamic range
b. frame averaging
c. gray scale
d. edge enhancement
e. receiver gain

Answer 13

b. frame averaging

Question 14

Under which circumstance is cavitation most likely to occur?

a. high frequency and low power
b. high intensity and high frequency
c. low intensity and low
frequency
d. low frequency and high signal amplitude

Answer 14

d. low frequency and high signal amplitude

Question 15

What is the accuracy of reflector depth position on an A-mode, B-mode or M-mode display called?

a. range resolution
b. horizontal calibration
c. axial resolution
d. s p e e d error artifact
e. depth calibration

Answer 15

e. depth calibration

Question 16

Pre-processing occurs

a. when the patient is scanned
b. when images are transferred to the VCR
c. after the images are on the tape
d. when the image exits the
scan converter

Answer 16

a. when the patient is scanned

Question 17

Post processing occurs when
the image

a. is played off o
f the VCR
b. entered the A/D converter
but before display
c. after ti leaves the A/D converter
d. after ti leaves the scan converter

Answer 17

b. entered the A/D converter
but before display

Question 17

The region from the transducer to the minimum beam cross-sectional area is the

a. Fraunhofer zone
b. Fresnel zone
c. focus
d. Snell’s length

Answer 17

b. Fresnel zone

Question 18

Biologic effects have not been documented below what intensity (SPTA)?

a. 100 W/cm
b. 100 mW/m2
c. 100 mW/cm2
d. 100 mW/cm3

Answer 18

c. 100 mW/cm2

Question 19

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

Answer 19

d. DICOM

Question 20

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

Answer 20

c. the ferroelectric material is depolarized

Question 21

What happens to venous blood flow to the heart during expiration?
a. increased
b. decreased .
c unchanged

Answer 21

b. decreased

Question 22

Which of the following has a propagation speed closest to “soft tissue”?

a. muscle
b. fat
.c bone
d. air

Answer 22

a. muscle

Question 23

In a B-mode display, which of the following axes are used for
the amplitude of the
reflection?

a. Z-axis
b. m-axis
c. x-axis
d. y-axis
e. time base axis

Answer 23

a. Z-axis

Question 24

What is displayed on the x-axis of an M-mode image? a. time b. time-of-flight c.reflector depth d. echo intensity e. red blood cell velocity

Answer 24

a. time

Question 25

What is displayed on the y axis of an m-mode image? a. time b. time-of-flight c. echo intensity d. red blood cell velocity

Answer 25

b. time-of-flight

Question 26

sonographer's education ends when they become registered. T or F

Answer 26

F

Question 27

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

Answer 27

a. amplitude

Question 28

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

Answer 28

a. at any time

Question 29

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

Answer 29

a. doubles

Question 30

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

Answer 30

b. PZT thickness

Question 31

While propagating, a 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

Answer 31

traveled in a straight line, reflected & returned

Question 32

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

Answer 32

d. hydrophone

Question 33

The impedance of tissue is 3 x 105 rayls and for the PZT crystal is 6 x 106 rayls. What is the best impedance for the matching layer? a. 63×106 b. 3,600 .с 10,000 d. 9.5 × 105 .e 9×104

Answer 33

d. 9.5 × 105

Question 34

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

Answer 34

c. air, water, bone

Question 35

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

Answer 35

c. shadowing

Question 36

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

Answer 36

d. location

Question 37

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

Answer 37

a. duty factor

Question 38

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

Answer 38

e. gray scale imaging

Question 39

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

Answer 39

a. focus

Question 40

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

Answer 40

d. ratio

Question 41

I the power of a sound wave is increased by a factor of 8, how many decibels is this? a. 3dB b. 6dB c. 9 ₫B d. 8 dB

Answer 41

c. 9 ₫B

Question 42

An ultrasound system is set at O 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

Answer 42

a. -3 dB

Question 43

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- ₫b b. -50 db c. 40 dB d. 3d8 e. -10 ₫b

Answer 43

e. -10 ₫b

Question 44

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

Answer 44

b. difference

Question 45

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

Answer 45

d. density and elasticity

Question 46

If 300,000 cycles occur in a second, what is the waves frequency? a. 3MHz b. 30 kHz c. 30 MHz d. 3kHz e. 0.3 MHz

Answer 46

e. 0.3 MHz

Question 47

What may be a unit of amplitude? a. cm b. HZ c. msec d. watts e, none of the above

Answer 47

a. cm

Question 48

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

Answer 48

d. 14 kHz

Question 49

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

Answer 49

a. reflected intensity of the sound beam

Question 50

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

Answer 50

d. near 100%

Question 51

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

Answer 51

c. halved

Question 52

Traveling through the same medium, if the frequency is doubled, the propagation speed is: a .u n c h a n g e d b. doubled c. halved d. quartered

Answer 52

a .u n c h a n g e d

Question 53

True or False. Increasing the frequency increases the penetration depth.

Answer 53

F

Question 54

True or False. Axial resolution is affected by focusing.

Answer 54

False

Question 55

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

Answer 55

c. frame rate

Question 56

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

Answer 56

a. propagation speed and the imaging depth

Question 57

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

Answer 57

a. depth of view

Question 58

Multiple reflections that are equally spaced are called: a. refractions b. reverberations c. shadows d. comets

Answer 58

b. reverberations

Question 59

What artifact has a grainy appearance and is caused by the interference effects of scattered sound? a. spackle b. reverberation c. slice thickness d. speckle e. section thickness

Answer 59

d. speckle

Question 60

Al of the following will improve temporal resolution EXCEPT: a. increased line density b. single rather than multi focus c. higher frame rate d. shallower depth of view e. slower speed of sound in a medium

Answer 60

a. increased line density

Question 61

Impedance is the product of ------- a n d ---------

Answer 61

Density, Propagation Speed

Question 62

The manufacturer increases the number of lines per frame. As a result, which of the following may have to be decreased? a. frequency b. frame rate c. sector angle d. imaging depth e. power output

Answer 62

b. frame rate c. sector angle d. imaging depth

Question 63

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

Answer 63

PZT, Crystal

Question 64

Sonographers cannot affect a patient's exposure to acoustic energy.

Answer 64

False

Question 65

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

Answer 65

d. 0.6 dB/cm/MHz

Question 66

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

Answer 66

c. 10

Question 67

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

Answer 67

T

Question 68

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

Answer 68

d. 2 times

Question 69

If 3MHz sound has 2dB of attenuation in 1cm of tissue, what is the amount of attenuation of 6MHz sound in 0.5cm of the same tissue? a. 5dB b. 2dB c. 10 d B d. 1.5dB

Answer 69

b. 2dB

Question 70

Volume has which of the following units? a. cm b. cm2 c. cm 3 d. cm 4

Answer 70

c. cm 3

Question 71

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

Answer 71

c. power

Question 72

What are typical clinical Doppler frequencies? a. 1-10,000Hz b. 1-10MHz c. 2 - 1 , 0 0 0 k Hz d. 40-45kHz

Answer 72

a. 1-10,000Hz

Question 73

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

Answer 73

d. 60-75 degrees

Question 74

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

Answer 74

d. display brightness & contrast

Question 75

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

Answer 75

c. is needed by all labs

Question 76

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

Answer 76

d. pulse duration

Question 77

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

Answer 77

a. refraction

Question 78

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

Answer 78

d. scan converter

Question 79

An US wave travels through two media and has attenuation of 3 dB 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

Answer 79

b. 8 dB

Question 80

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.1 0 0

Answer 80

c. 0.1

Question 81

Fill-in of an anechoic structure s u c h 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

Answer 81

d. ghosting artifact

Question 82

What si the range of frequencies created by medical diagnostic Doppler transducers? a. 4-10Hz b. 10-20MHz c. 1-10 kHz d. 2-20Hz e. 2 - 10MHz

Answer 82

e. 2 - 10MHz

Question 83

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

Answer 83

False

Question 84

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. ti determines the ensemble length

Answer 84

it represents the number of red blood cells creating the reflection

Question 85

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

Answer 85

e. reflector spacing and propagation speed

Question 86

From a safety stand point, which of the following methods is best? a. low transmit output and 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

Answer 86

a. low transmit output and high receiver gain

Question 87

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

Answer 87

e. one million times

Question 88

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

Answer 88

c 2kHz

Question 89

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

Answer 89

False

Question 90

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

Answer 90

False

Question 91

(True or False) Doppler shifts always occur fi 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.

Answer 91

True

Question 92

When the sound source and the receiver are not moving directly toward or away from each other, the angle b e t w e e n t h e m enters into the calculation of Doppler shift. a. average b. slope c. sine .d cosine

Answer 92

.d cosine

Question 93

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

Answer 93

c. time-of-flight, propagation speed

Question 94

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

Answer 94

a. propagation speed

Question 95

What is another name for longitudinal resolution? a. axial b. Depth c. Lateral d. Transverse

Answer 95

a. axial b. Depth

Question 96

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

Answer 96

a. reverberations

Question 97

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

Answer 97

Compensation

Question 98

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

Answer 98

Compression

Question 99

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

Answer 99

c. the frame rate decreases