Brainscape's Knowledge GenomeTM

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


See full index

Vascular II & Physics II > Physics Ch. 13 & 14 > Flashcards

Physics Ch. 13 & 14 Flashcards

1
Q

The slope of the electrical spike line determines the ______ of the sound beam

A

steer direction

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

How many elements are in a mechanical transducer

A

one single, circular, disc shaped

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

If the spike line is straight (no curve) the sound beam will be

A

unfocused

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

Focusing may occur during

A

both transmission and reception

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

Phased array always means ______ or “multi focus”

A

adjustable

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

The _____ pattern controls the steering of the beam and the ______ pattern controls the focusing of the beam

A

slope, curved

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

If the right electrical spike excites the right active element first, followed by the next and so on, the beam will be steered in what direction

A

left

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

Can focusing only be performed during transmission

A

no

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

What type of transducer creates a trapezoidal-shaped image

A

vector

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

What type of transducer is comprised of multiple ring-shaped elements

A

annular

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

What type of transducer creates a rectangular-shaped image

A

linear sequential

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

What type of transducer creates a blunted sector-shaped image

A

curvilinear

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

With which type of transducer with a damaged PZT crystal results in a horizontal band of dropout in the image

A

annular

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

What affect is there on the ultrasound image if there is one crystal damaged, using a mechanical transducer

A

entire image is lost

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

Temporal resolution is determined by

A

frame rate

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

Two sonographer-controlled settings of an ultrasound system that determine frame rate are:

A

imaging depth, # pulses per picture

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

Deep imaging will result in a _______ go-return time, a ______ T frame, a _____ frame rate and ______ temporal resolution

A

long, longer, lower, inferior

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

What results from using multi-focus: pulses per scan line, t frame, frame rate, temporal resolution, lateral resolution

A

many, longer, lower, inferior, improved

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

Use of a narrower sector will result in a _____ frame rate

A

higher

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

High line density will result in _____ pulses per frame, ______ frame rate, _____ temporal resolution and ______ spatial resolution

A

more, lower, inferior, superior

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

time frame x frame rate=

A

1

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

Time frame and frame rate are _____ related

A

inversely

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

What is the frame rate if each image of the ultrasound system is created in 0.02 sec (1/50 sec)

A

50 Hz

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

An annular phased array transducer uses ______ steering and _____ focusing

A

mechanical, beam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Name 3 things that the pulser determines

A

amplitude, PRP, PRF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

During transmission transforms electrical energy into acoustic energy and during reception, converts acoustic energy into electrical energy

A

transducer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Maintains and organizes the proper timing and interaction of the system’s components

A

master synchronizer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Transforms the electrical signals from the transducer into a form suitable for display

A

receiver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Archives the ultrasound studied

A

storage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Presents processed data

A

Display

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Determines the amplitude, PRP, PRF

A

pulser

32
Q

Determines the firing delay patterns for phased array systems

A

Beam former

33
Q

Increasing ______ is the most common to improve (increase) the signal-to-noise ratio

A

output power

34
Q

What are the 5 operations of the receiver (in appropriate order)

A

amplification, compensation, compression, demodulation, reject

35
Q

Are all electrical signals in the receiver affected identically by amplification

A

yes

36
Q

Compensation is also known as ______ compensation, ______ gain compensation and _____ gain

A

time-gain, depth, swept

37
Q

Regarding the TGC curve, what is the region where compensation corrects for the effects of increasing attenuation that result from increasing path length (depth)

A

slope

38
Q

What is the function of the receiver that keeps an image’s gray scale content within the range of detection of the human eye

A

compression

39
Q

What are the 2 processes that occur during demodulation

A

rectification, smoothing/enveloping

40
Q

What effect does demodulation have on the ultrasound image

A

none

41
Q

The rejection function affects ______ echoes, regardless of their location

A

low-level

42
Q

Based on the ALARA principle when modifications to either output power or receiver gain can improve the diagnostic quality of an image: if an image is too dark you should first increase _______

A

receiver gain

43
Q

Compensation creates an image that is uniformly bright from

A

top to bottom

44
Q

A ______ is made up of a single PZT active element in the transducer, the electronics in the beam former/pulser and the wire that connects them

A

channel

45
Q

Does the beam former function with array transducers during transmission, reception, or both

A

both

46
Q

The beam former adjusts electrical spike voltages to reduce lobe artifacts in a process called

A

apodization

47
Q

Lateral resolution improves with

A

multi-focusing

48
Q

Spatial resolution improves with

A

higher line density

49
Q

What form of resolution improves when frame rate increases

A

temporal (directly related)

50
Q

What is consistent with improved temporal resolution

A

frame rate

51
Q

A sonographer adjusts an ultrasound scan to double the depth of view from 5cm to 10cm. What happens to the frame rate

A

It is halved

52
Q

A sonographer adjusts an ultrasound scan to double the depth of view from 5 cm to 10 cm. Is the frame rate remains the same, which one of the following also occurs

A

narrow sector

53
Q

A sonographer adjusts an ultrasound machine to change the sector size from 90 to 45 degrees. Nothing else changes. What happens to the frame rate

A

Is is doubled

54
Q

A sonographer adjusts an ultrasound system to change the sector size from 90 to 45 degrees. The frame rate was unchanged. What else must have happened

A

line density was doubled

55
Q

A sonographer, using a phased array ultrasound system, turns off the multi-focus feature. What is the most likely consequence of this action

A

temporal resolution improves

56
Q

A sonographer increases the line density from 1 line per degree of sector to 3 lines per degree of sector. What is the most likely consequence of this action

A

temporal resolution decreases

57
Q

A sonographer reduces the sector angle from 90 degrees to 30 degrees. At the same time, the ultrasound system automatically increases the line density from 1 line per degree to two lines per degree. No other changes are made. What will happen to the frame rate

A

increases

58
Q

A sonographer reduces the sector angle from 90 degrees to 30 degrees. At the same time, the ultrasound system automatically increases the line density from 1 line per degree to 3 lines per degree. No other changes are made. What will happen to temporal resolution

A

remains unchanged

59
Q

What is most important in determining the frame rate of a system

A

speed of sound in the medium

60
Q

What is the frame rate if each image of the ultrasound system is created in 0.02 sec (1/50 sec)

A

50 Hz

61
Q

What is the time needed to make a single image if the frame rate of an ultrasound system is 20 Hz

A

0.05 s

62
Q

T/F. The critical factor in determining frame rate, line density, and imaging depth is the transducer style

A

False, time

63
Q

T/F. The number of lines per frame and the frame rate determine the frequency

A

False, PRF

64
Q

T/F. The number of lines per frame and frame rate determine the PRF

A

true

65
Q

T/F. If the imaging depth of a scan is 15cm and there are 100 lines in the image, then the number of pulses making up the scan is 100

A

true

66
Q

T/F. If 100 scan lines make up an image and the frame rate is 30 per second, then the system’s PRF is 3000 Hz

A

true

67
Q

When the frame rate is 30 Hz, how long does it take to create a frame

A

1/30 sec

68
Q

Under certain conditions, an ultrasound system creates each image in 0.01 seconds. What is the frame rate

A

100 Hz

69
Q

What is the fundamental limitation of temporal resolution

A

speed of sound in the medium

70
Q

This type of pulser generates a constant electrical signal in the form of a sine wave

A

continuous wave

71
Q

This type of pulser generates a single electrical spike, which ultimately creates a single sound pulse

A

pulsed wave, single crystal

72
Q

This type of pulser generates numerous electrical spikes, which ultimately create a single sound pulse

A

pulsed wave, phased array

73
Q

The acoustic power of a sound beam emitted from a transducer is determined by the _____ of the pulser’s signal

A

voltage

74
Q

T/F. Amplification processes all reflected signals in a similar manner

A

true

75
Q

T/F. Compensation processes all reflected signals in a similar manner

A

false, barely compensated from shallow

Vascular II & Physics II (21 decks)

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