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Flashcards in FInal part II Deck (85):
1

Based on the acquisition and review of information from patients or animals exposed to ultrasound
exposure and response
no need to understand mechanism (+ and -)
biological significance is obvious (+)
species differences may alter results (-)
Strongest conclusion are made when the mechanistic and empirical conclusion are in agreement


1. Empirical approach

2

2. Contrast, shrinking and swelling

Resonance, nonlinear behavior

3

3. Primary investigative technique of epidemiology

Reviewing data from patients

4

4. Intensity most related to tissue heating

SPTA

5

5. Bioeffect studies on non-living things

Mechanistic Approach

6

What type of trans causes less amount of temperature increase

Grey scale image Q.# 13, pg 421

7

7. Possibility of patient technologist shock

Mechanical Transducer

8

8. When is it safe to perform in Ultrasound

When the benefits outweight the risk

9

9. Electronic component used for gray scale imaging

Scan converter pg.241

10

Preprocessing: TGC, log compression, write magnification, persistence spatial compounding, edge enhancement, and fill-in enhancement

10. Know all of the preprocessing and post processing functions

11

11. What function steers the scan lines in different directions

Spatial compounding pg.254

12

Virtually instant
no degradation of data, and the ability to electronically transmit images
report to remote sites (“store and forward”)

12. Advantages of PACs systems

13

12. Advantages of PACs systems

Virtually instant
no degradation of data, and the ability to electronically transmit images
report to remote sites (“store and forward”)

14

Safe
metaboliccaly inert
long lasting
strong reflector of ultrasound
small enough to pass through capillaries

14. Know the requirements for contrast agents

15

13. Signal from the transducer to the receiver

.?

16

14. Know the requirements for contrast agents

Safe
metaboliccaly inert
long lasting
strong reflector of ultrasound
small enough to pass through capillaries

17

harmonics vs fundamental frequencies

Harmonics is double the fundamental frequency
Harmonics has nonlinear behavior

18

16. Accelerations and deceleration of velocities from cardiac contraction

Pulsitile Flow

19

Acceleration and deceleration of velocities from respiration

Phasic Flow

20

change in flow direction
increased velocity as vessels narrows
turbulence downstream from the stenosis
pressure gradient across the stenosis
loss of pulsitility

20. Know the effects of a stenosis

21

Supine:
Hydrostatic- 0 mmHg
Blood pressure is same (140 mmHg)

Standing:
Hydrostatic
-ankle - 100 mmHg
- knee - 75 mmHg
-waist - 50 mmHg
-heart/arm - 0 mmHg
- Forehead - -30 mmHg
- Tip of finger - -130 mmHg
Blood pressure is arterial of heart + hydrostatic

21. Know hydrostatic pressure at all locations

22

18. Flow pattern with normal physiological states

Laminar Flow

23

19. Reynolds number for turbulent flow?

Greater than 2,000

24

20. Know the effects of a stenosis

change in flow direction
increased velocity as vessels narrows
turbulence downstream from the stenosis
pressure gradient across the stenosis
loss of pulsitility

25

21. Know hydrostatic pressure at all locations

Supine:
Hydrostatic- 0 mmHg
Blood pressure is same (140 mmHg)

Standing:
Hydrostatic
-ankle - 100 mmHg
- knee - 75 mmHg
-waist - 50 mmHg
-heart/arm - 0 mmHg
- Forehead - -30 mmHg
- Tip of finger - -130 mmHg
Blood pressure is arterial of heart + hydrostatic

26

22. What is it referred to when the vessel collapses venous

coaptation

27

Baseline
lower frequency
Shallower volume depth
Adjust scale
CW

27. Five ways to eliminate aliasing

28

23. Venous flow in the leg decreases what is the patient doing?

Inspiration

29

24. Doppler shift when source and receiver are moving apart?

Negative

30

25. What is the typical range of Doppler shift

20 Hz- 20KHz
Audible

31

26. Phenomena of high velocities appear negative

Aliasing

32

able to select the exact location where velocities are measured

32. Primary advantages of pulsed wave

33

27. Five ways to eliminate aliasing

Baseline shift
lower frequency transducer
Shallower sample volume depth
Adjust scale
CW

34

34. Know what limitation is for color Doppler imaging

No measurement of velocity or direction.
Lower frame rate.
Susceptible to motion of transducer, patient, or soft tissue- flash artifact.

35

No measurement of velocity or direction.
Lower frame rate.
Susceptible to motion of transducer, patient, or soft tissue- flash artifact.

34. Know what limitation is for color Doppler imaging

36

28. Horizontal axis of a Doppler spectrum

time

37

29. Doppler shift is inversely related to?

Propagation speed

38

30. Basic Doppler system just had just identified a frequency shift

Non- or uni- directional doppler

39

31. Couple questions, just know that traveling towards the transducer and away

Positive when flowing towards the transducer

Negative when it is flowing away from the transducer

40

32. Primary advantages of pulsed wave

Range resolution, range specificity, and freedom from range ambiguity artifact
able to select the exact location where velocities are measured

41

violation of assumptions
equipment malfunction or poor design
the physics of ultrasound
operator

40. Know the cause for artifacts

42

33. Primary advantages of continuous wave

ability to accurately measure very high velocities

43

35. What is the area of interrogation for Doppler

Sample volume or gate

44

36. What method will have increased sensitivity for low flow states

Power mode doppler

45

37. This describes the portions of the image that are brighter than surrounding tissues

Hyperechoic

46

38. Structures without echoes?

Anechoic

47

39. Similar echo chara?

homogenous

48

40. Know the cause for artifacts

violation of assumptions
equipment malfunction or poor design
the physics of ultrasound
operator

49

41. Multiple equally spaced parallel lines what artifact

Reverberation

50

42. Which artifact is unrelated to the US pulse

Enhancement

51

43. Which artifact produces an image with incorrect number of reflectors

Refraction

52

44. Two distinct reflectors one is an artifact one is deeper than the other

Mirror

53

45. What is the artifact if they are side by side

Lateral resolution

54

Similar to soft tissue
Speed of sound, attenuation, scattering characteristics, echogenicity Pg. 382

54. Know about tissue equivalent phantom

55

55. Know about conformed consent

(autonomy)

56

56. Know about gold standard

A perfect technique, for example MRI or angiography, that we deem 100% accurate to which our ultrasound results are compared.

57

A perfect technique, for example MRI or angiography that we deem 100% accurate to which our ultrasound results are compared.

56. Know about gold standard

58

46. Which artifact creates only one reflections with two reflectors

Axial Resolution

59

59. Know the intensity limits for unfocused and focused transducers

Unfocused- 100mW/cm^2
Focused- 1W/cm^2 or 1000mW/cm^2

60

47. Lobes created by array transducers what are they called

grating lobe

61

48. Refraction at the edge of circular structure what is it called

Edge shadowing

62

49. When there is too much gain in the focal zone what is it called

Focal Enhancement

63

50. Which artifact occurs when you see reflectors at incorrect depths

Range ambiguity

64

51. A grainy appearance?

Speckle

65

52. If your PRF is to high what artifact

Range ambiguity

66

53. What artifact found only with Doppler?

Cross talk

67

54. Know about tissue equivalent phantom

Similar to soft tissue
Speed of sound, attenuation, scattering characteristics, echogenicity Pg. 382

68

55. Know about conformed consent

patients are educated about medical procedure(autonomy)

69

57. Ability to position echoes in their correct position along distance perpendicular to the sound

Lateral resolution

70

58. Stratigicle located pins cysts in masses what kind of phantom

Tissue equivalent phantom

71

70. Know the difference of output power and receiver gain

output power effects bioeffects. Receiver gain has no effects on bioeffects. You should always decrease your output power first then adjust your receiver gain.

72

60. Know appropriate way to introduce yourself to the Patient

Tell them your name and what type of exam you are performing

73

61. Know all and what happens to the image and know all the transducers a lot of questions from the transducers

??

74

62. Use of more active elements to receive reflections with a greater time of flight

??

75

63. Know all about temporal spatial and contrast resolution

??

76

64. Lateral resolution improves with what

.?

77

65. Wanted you to figure out the time it takes to make a single image when looking the frame rate, know how to calculation

??

78

66. Imaging depth is 15cm, 100 lines number of pulses making up a scan is what

??

79

67. Know all about component of the US system

??

80

68. TGC curve know the anatomy of that

??

81

69. Of the receiver functions know which one treats the signal differently due to the depth of the reflector

??

82

70. Know the difference of output power and receiver gain

Output power is harmful to bioeffects. Receiver gain isn't.
If the image is to bright you should always decrease output power first then do receiver gain.

83

71. Know which function will affect the strength of every pulse transmitted into the body

??

84

72. Reflectors displayed only in the far region what would you have to do

??

85

Any change after freeze frame
black/white inversion
read magnification
contrast variation 3-D rendering

Following question 10. postprocessing