Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

DRG3007 Sono > Week 1 - US Basics > Flashcards

Week 1 - US Basics Flashcards

1
Q

audible sound range

A

20 - 20k Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

ultrasound range

A

> 20 kHz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Diagnostic Ultrasound range

A

1MHz - 20 MHz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are waves

A

disturbance away from average condition which carries only energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

types of waves

A

mechanical & electromagnetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

mechanical waves ___

A

propagate through physical mediums like sound & water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

electromagnetic waves ___

A

travel through space/vacuum without needing a physical medium such as heat & x-rays

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

types of mechanical waves

A

transverse + longitudinal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

transverse wave particles move ___

A

perpendicular to direction of wave propagation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

longitudinal wave particles move ___

A

parallel / anti-parallel to wave motion; oscillate back and forth in their resting positions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

variables of sound

A

wave speed, frequency, wavelength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

speed of sound is dependent on ___

A

media density & compressibility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

speed of sound is constant for particular medium as long as temperature is ___

A

constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

the average speed of soft tissue using ultrasound is ___

A

1540m/s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

the denser the medium, the ___ the sound wave propagation

A

slower

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

density refers to the __

A

number of particles per unit volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

compressibility refers to

A

how easy the volume of material can change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

the more compressible the medium is, the __ sound waves propagate

A

faster

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

compressibility & density of a substance are ___

A

interdependent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

1 kHz is ___ cycles per sec

A

1000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

diagnostic ultrasound frequency

A

2 - 18 MHz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

ultrasound wavelength ranges between ____

A

0.1 to 1.0mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Attenuation

A

redirected energy that is lower in energy compared to incident wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

sound & matter interactions

A

SARR

Scattering, Attenuation, Reflection, Refraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

For attenuation, the deeper the wave travels in the body, the ___ it becomes

A

weaker

25
Q

attenuation =

A

absorption + scattering

26
Q

what happens to the tissue during absorption

A

tissue energy content increases while beam intensity decreases during transmission

27
Q

intensity loss formula

A

intensity loss = μ x f x z

μ = intensity attenuation coefficient
z = distance travelled in cm

28
Q

attenuation coefficient is the ___

A

loss of intensity in decibels per tissue cm traversed per megahertz

29
Q

attenuation coefficient is ___ proportional to frequency

A

directly

30
Q

attenuation coefficient unit is __

A

dB/cm

31
Q

attenuation factors

A

tissue type, frequency, depth

32
Q

low frequency = ____ depth of penetration

A

high

33
Q

acoustic impedance is defined as the ____

A

medium resistance to sound transmission

34
Q

acoustic impedance formula

A

Z (acoustic impedance) = p (density) x c (sound velocity)

35
Q

acoustic impedance unit

A

rayl

36
Q

if acoustic impedance in 2 mediusm are the same, sound will travel ___

A

readily from one to another

37
Q

if acoustic impedance in 2 mediusm are not the same, a portion of the sound will be ___

A

reflected at interface

38
Q

what allows for visualization of soft tissue structures within US beam

A

acoustic impedance

39
Q

difference in acoustic impedance between 2 tissues causes ___

A

sound wave reflection

40
Q

reflection is determined by ___ of interface

A

size & surface

41
Q

reflections occur at ___ between 2 adjacent tissues

A

boundary / interface

42
Q

reflection coefficient

A

amount of US beam reflected at interface

43
Q

% reflection of fat/muscle

A

1.08

44
Q

% reflection of fat/kidney

A

0.6

45
Q

% reflection of soft tissue / water

A

0.2

46
Q

% reflection of bone/fat

A

49

47
Q

% reflection of soft tissue / air

A

99

48
Q

specular reflection

A

US strikes smooth boundary = interface large & relatively smooth with max reflection at 90 degrees

49
Q

non-specular reflection

A

US strikes boundary w/ irregular surface & multiple interfaces = sound deflects in multiple directions

50
Q

refraction follows what law

A

snell’s law

51
Q

greater diff of velocity = __ refraction

A

increased

52
Q

critical angle is defined as __

A

incident angle for which refraction angle is 90 degrees

53
Q

what happens to the beam at the critical angle

A

refracted beam travels along interface

54
Q

common US artifacts

A

CARD

  • reverberation
  • dirty vs clean acoustic shadowing
  • acoustic enhancements
  • comet-tail artifacts
55
Q

reverberation occurs when ___

A

beam encounters 2 highly reflective surfaces

56
Q

acoustic shadowing occurs due to __

A

reduction in echo strength distal to high attenuating / reflective object

57
Q

what benefit does acoustic shadowing offer

A

visualize calcifications; often seen with bone & calcifications

58
Q

where does clean shadowing occur commonly

A

distal to larger calculi & bone as a dark anechoic band

59
Q

where does dirty shadowing occur commonly

A

distal to highly reflecting surface as multiple secondary reflections of low level echos that appear within the shadow

60
Q

comet tail artifacts appear as ___

A

multiple internal reflections within small reflective object producing many short tapered echoes

61
Q

energy loss during reverberation process causes echoes to ___

A

decrease in width & brightness

DRG3007 Sono (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions