Chapter 8/9 Kremkau Final

Question 1

a small transducer element mounted on the end of a narrow tube; a piezoelectric membrane with small metallic electrodes

Answer 1

hydrophone

Question 2

tissue-equivalent device that has characteristics that are representative of tissues

Answer 2

phantom

Question 3

the force exerted by a sound beam on an absorber or reflector

Answer 3

radiation force

Question 4

a device without tissue-like properties that is designed to measure some characteristic of an imaging system

Answer 4

test object

Question 5

Which of the following is not assessed with a tissue equivalent phantom?
a. penetration
b. beam width
c. dynamic range
d. TGC operation

Answer 5

b

Question 6

Tissue equivalent phantoms are filled with a substance containing ______.

Answer 6

graphite

Question 7

Which of the following cannot be measured or calculated by a hydrophone?
a. period
b. amplitude
c. impedance
d. pulse duration

Answer 7

c

Question 8

Which of the following pulsed imaged techniques demonstrates the highest acoustic output?
a. gray-scale
b. motion mode
c. color-doppler
d. spectral doppler

Answer 8

d

Question 9

Test objects evaluate _______.

Answer 9

detail resolution

Question 10

A hydrophone is used in the following form(s):
a. a small transducer element mounted on end of hollow needle
b. a large piezoelectric membrane with small electrodes on both sides
c. both a and b
d. neither

Answer 10

c

Question 11

which of the following pulsed-wave techniques demonstrates the lowest sonographic output?
a. motion mode
b. gray scale
c. color doppler
d. spectral doppler

Answer 11

b

Question 12

Doppler test objects and flow phantoms enable the evaluation of all of the following except:
a. spectral display and calibration
b. color doppler spatial resolution
c. sample volume location
d. penetration of spectral and color Doppler instruments

Answer 12

b

Question 13

True or False:

Hydrophones are used to measure the acoustic output of various sonographic instruments

Answer 13

true

Question 14

True or False:

Doppler test objects and flow phantoms are not able to evaluate gate location.

Answer 14

false

Question 15

In soft tissue, a temperature is considered significant once it exceeds _____.

Answer 15

1.5 degrees celcius

Question 16

which of the following describes cavitation?
a. flow in an absorbing fluid
b. conversion of ultrasound to heat
c. temperature rise as ultrasound propagates through tissue
d. production and behavior of bubbles in a liquid medium

Answer 16

d

Question 17

No bioeffects have been observed in mammation tissues that contained well-defined gas bodies at peak rarefactional pressure values (mPa) of less than ____

Answer 17

0.4

Question 18

Plant studies are used primarily for _____.

Answer 18

understanding cavitational effects in living tissue

Question 19

The extent of temperature rise produced depends on ____ and _____.

Answer 19

intensity and frequency

Question 20

which of the following pulsed imaging techniques demonstrates the highest acoustic output?
a. gray scale
b. motion mod
c. color doppler
d. spectral doppler

Answer 20

d

Question 21

No bioeffects have been observed in mammation tissues at mechanical index values of less than ____.

Answer 21

0.4

Question 22

Attenuation in soft tissue is due primarily to

Answer 22

absorption

Question 23

which of the following relates to heating?
a. impedance
b. sound speed
c. distance from transducer
d. absorption

Answer 23

d

Question 24

a significant increase in the temperature of tissues close to the transducer is a result of _____.

Answer 24

transducer self-heating

Question 25

A tissue-equivalent _____ has an attenuation of approximately 0.5 dB/cm-MHz and a propagation speed of 1.54 mm/us. A ______ does not mimic tissue but provides a means for measuring some aspect of instrument performance.

Answer 25

phantom, test object

Question 26

True or False: Test objects and phantoms are available commercially

Answer 26

true

Question 27

true or false: Test objects and phantoms can be used by the instrument operator.

Answer 27

true

Question 28

A moving ____ test object is useful in checking the accuracy of Doppler spectral displays.

Answer 28

string

Question 29

A _____ phantom is useful in simulating physiologic ______ conditions for a Doppler instrument.

Answer 29

flow, flow, f

Question 30

Which of the following is used for Doppler sensitivity measurements? a. cyst phantom b. profile test object c. string test object d. contrast phantom e. none of the above

Answer 30

e

Question 31

tissue-equivalent phantoms attempt to represent some acoustic property of _____.

Answer 31

tissues

Question 32

true or false: The string test object measures volumetric flow rate.

Answer 32

false

Question 33

With use of a hydrophone, which of the following can be measured or calculcated. (There is more than one correct answer) a. impedance b. amplitude c. period d. pulse duration e. pulse repetition period

Answer 33

bcde

Question 34

True or false: All hydrophones consist of a small element mounted on the end of a needle.

Answer 34

false

Question 35

A needle hydrophone contains a small ______ element.

Answer 35

transducer and piezoelectric

Question 36

True or false: Because of its small size, a hydrophone can measure spatial details of a sound beam.

Answer 36

true

Question 37

A hydrophone _____. a. interacts with light b. produces a voltage c. measures intensity directly d. measures total energy e. none of the above

Answer 37

b

Question 38

Heating depends most directly on:

Answer 38

SATA intensity

Question 39

Conditions under which cavitation may occur are best described by ____.

Answer 39

peak rarefactional pressure

Question 40

Bioeffects have been observed in experimental animals with intensities greater than ____.

Answer 40

100mW/cm^2 SPTA

Question 41

Bioeffects have been observed in experimental animals with focused intensities greater than _____.

Answer 41

1 mW/cm SPTA

Question 42

Focal lesions have been observed in experimental animals with intensities greater than _____.

Answer 42

10 W/cm SPTA

Question 43

True or False The available epidimiologic data are sufficient to make a final judgement on the safety of diagnostic ultrasound.

Answer 43

false

Question 44

Exposure is minimized by using diagnostic ultrasound ____.

Answer 44

only when indicated, with minimum intensity, with minimum time

Question 45

Which of the following is (are) used currently to indicate output on the display? a. percent b. display c. SPTA intensity d. mechanical index e. all of the above

Answer 45

e

Question 46

Which of the following affect(s) exposure of a fetus? a. intensity at the transducer b. distance to the fetus c. frequency d. gain e. more than one of the above f. all of the above

Answer 46

e (a,b,c)

Question 47

True or false There is no possible hazard involved in the use of diagnostic ultrasound

Answer 47

false

Question 48

True or false Ultrasound should not be used as a diagnostic tool because of the bioeffects it can produce

Answer 48

false

Question 49

No independently confirmed, significant bioeffects in mammalian tissues have been reported at intensities below _____.

Answer 49

100 mW/cm^2 SPTA

Question 50

Is there any known risk with the current use of diagnostic ultrasound?

Answer 50

no

Question 51

are there any bioeffects that ultrasound produces in small animals under experimental conditions?

Answer 51

yes

Question 52

Which of the following are mechanisms by which ultrasound can produce bioeffects? a. direction ionization b. absorption c. photoelectric effect d. cavitation e. Compton effect

Answer 52

b and d

Question 53

Which of the following relates to heating? a. impedance b. sound speed c. absorption d. refraction e. diffraction

Answer 53

c

Question 54

Which of the following endpoints is documented well enough in the scientific literature to allow a risk assessment for diagnostic ultrasound to be based on it? a. fetal weight b. sister-chromatid exchange c. fetal abnormalities d. carcinogenesis e. none

Answer 54

e

Question 55

On which of the following endpoints has more than one epidemiologic study shown a statistically significant effect of ultrasound exposure? a. fetal activity b. birth weight c. fetal abnormalities d. dyslexia e. none

Answer 55

e

Question 56

Which of the following acoustic parameters has (have) been documented in ultrasound epidemiologic studies published thus far? a. frequency b. exposure time c. intensity and pulsing conditions d. scanning patterns e. none

Answer 56

e

Question 57

A device commonly used to measure the output of diagnostic ultrasound instruments is a(n) _____.

Answer 57

hydrophone

Question 58

A typical output intensity (SPTA) for an ultrasound imaging instrument is ____.

Answer 58

1 mW/cm^2

Question 59

Which of the following typically has the highest output intensity? a. fetal monitor Doppler b. duplex pulsed Doppler c. color-Doppler shift d. phase array, gray scale

Answer 59

b

Question 60

As far as we know now, which of the following is the most correct and informative response to a patient's question, "Will this hurt me or my baby?" a. no b. yes c. We don't know d. The risks are well understood, but the benefits always outweigh them e. there is no known risk with ultrasound imaging as it is applied currently

Answer 60

e

Question 61

To minimize whatever risk there may be with ultrasound imaging, which of the following should be done? a. can to produce pictures for the family album b. scan to determine fetal sex c. minimize exposure time d. scan for medical indication(s) only e. minimize exposure intensity

Answer 61

c d e

Question 62

Which of the following controls affect instrument output intensity? a. dynamic range, compression b. transmit, output c. near gain, far gain d. overall gain e. slope, time gain compensation

Answer 62

b

Question 63

Which of the following are correct for a duplex, pulsed-wave Doppler instrument? a. tissue anywhere in the Doppler beam is exposed to ultrasound b. tissue anywhere in the imaging plane is exposed to ultrasound c. Imaging intensities are higher than for conventional gray-scale instruments d. Doppler intensities are higher than for continuous-wave fetal monitoring

Answer 63

a b d

Question 64

The tissue of greatest concern regarding bioeffects in an abdominal scan is the ____.

Answer 64

fetus

Question 65

Would it be wise to substitute a duplex, pulsed-wave Doppler device for an inoperative fetal monitor for long-term monitoring in labor?

Answer 65

no

Question 66

Which of the following is (are) likely to be exposed to ultrasound during a diagnostic study? a. patient b. sonographer c. sonologist d. observers in the room e. more than one of the above

Answer 66

a

Question 67

No bioeffects have been observed in nonhuman mammalian tissues at thermal index values of less than _____.

Answer 67

2

Question 68

No bioeffects have been observed in nonhuman mammalian tissues at mechanical index values of less than ____.

Answer 68

0.4

Question 69

No bioeffects have been observed in nonhuman mammalian tissues at peak rarefactional pressure values (megapascals) of less than _____.

Answer 69

0.4

Question 70

ALARA is an abbreviation for _____.

Answer 70

as low as reasonably achievable

Question 71

A tissue-equivalent ____ has an attenuation of approximately 0.5 dB/cm-MHz and a propagation speed of 1.54 mm/us. A ______ does not mimic tissue but provides a means for measuring some aspect of instrument performance.

Answer 71

phantom, test object

Question 72

Test objects and phantoms are available commericially

Answer 72

true

Question 73

Test objects and phantoms can be used by the instrument operator.

Answer 73

true

Question 74

A moving _____ test object is useful in checking the accuracy of Doppler spectral displays

Answer 74

string

Question 75

A _____ phantom is useful in simulating physiologic _____ conditions for a Doppler instrument.

Answer 75

flow, flow,

Question 76

Which of the following is used for Doppler sensitivity measurements? a. cyst phantom b. profile test object c. string test object d. contrast phantom e. none of the above

Answer 76

e

Question 77

Tissue-equivalent phantoms attempt to represent some acoustic property of _____

Answer 77

tissues

Question 78

The string test object measures volumetric flow rate.

Answer 78

false

Question 79

With use of a hydrophone, which of the following can be measured or calculated? a. impedance b. amplitude c. period d. pulse duration e. pulse-repetition period

Answer 79

b c d e

Question 80

All hydrophones consist of a small element mounted on the end of a needle

Answer 80

false

Question 81

A needle hydrophone contains a small _____ element.

Answer 81

transducer/piezoelectric

Question 82

Because of its small size, a hydrophone can measure spatial details of a sound beam.

Answer 82

true

Question 83

A hydrophone ______.

Answer 83

produces a voltage

Question 84

Heating depends most directly on

Answer 84

SATA intensity

Question 85

Conditions under which cavitation may occur are best described by _____

Answer 85

peak rarefactional pressure

Question 86

Bioeffects have been observed in experimental animals with intensities greater than ______

Answer 86

100 mw/cm2 SPTA

Question 87

Bioeffects have been observed in experimental animals with focused intensities greater than ______

Answer 87

1 W/cm SPTA

Question 88

Focal lesions have been observed in experimental animals with intensities greater than ______.

Answer 88

10 W/cm SPTA

Question 89

The available epidemiologic data are sufficient to make a final judgment on the safety of diagnostic ultrasound.

Answer 89

False

Question 90

Exposure is minimized by using diagnostic ultrasound _____.

Answer 90

with minimum intensity, time, and when indicated

Question 91

Which of the following is (are) used currently to indicate output on the display? a. percent b. decibel c. SPTA intensity d. mechanical index e. all of the above

Answer 91

e

Question 92

Which of the following affect(s) exposure of a fetus? a. intensity at the transducer b. distance to the fetus c. frequency d. gain e. more than one of the above f. all of the above

Answer 92

e

Question 93

There is no possible hazard involved in the use of diagnostic ultrasound.

Answer 93

false

Question 94

Ultrasound should not be used as a diagnostic tool because of the bioeffects it can produce

Answer 94

flase

Question 95

No independently confirmed, significant bioeffects in mammalian tissues have been reported at intensities below _____.

Answer 95

100 mW/cm2 SPTA

Question 96

Is there any known risk with the current use of diagnostic ultrasound?

Answer 96

no

Question 97

Are there any bioeffects that ultrasound produces in small animals under experimental conditions?

Answer 97

yes

Question 98

Which of the following are mechanisms by which ultrasound can produce bioeffects? a. direct ionization b. absorption c. photoelectric effect d. cavitation e. Compton effect

Answer 98

b d

Question 99

Which of the following relates to heating? a. impedance b. sound speed c. absorption d. refraction e. diffraction

Answer 99

c

Question 100

Which of the following endpoints is documented well enough in the scientific literature to allow a risk assessment for diagnostic ultrasound to be based on it? a. fetal weight b. sister-chromatid exchange c. fetal abnormalities d. carcinogenesis e. none

Answer 100

e

Question 101

On which of the following endpoints has more than one epidemiologic study shown a statistically significant significant effect of ultrasound exposure? a. fetal activity b. birth weight c. fetal abnormalities d. dyslexia e. none

Answer 101

e

Question 102

Which of the following acoustic parameters has (have) been documented in ultrasound epidemiologic studies published thus far? a. frequency b. exposure time c. intensity and pulsing conditions d. scanning patterns e. none

Answer 102

e

Question 103

A device commonly used to measure the output of diagnostic ultrasound instruments is a(n) _____

Answer 103

hydrophone

Question 104

A typical output intensity (SPTA) for an ultrasound imaging instrument is

Answer 104

1 mW/cm2

Question 105

Which of the following typically has the highest output intensity? a. fetal monitor Doppler b. duplex pulsed Doppler c. color- Doppler shift d. color power Doppler e. phase array, gray scale

Answer 105

b