Brainscape's Knowledge GenomeTM

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


See full index

Vascular II & Physics II > Ch. 24 Physics > Flashcards

Ch. 24 Physics Flashcards

1
Q

What are the two types of bioeffects

A

thermal, cavitation

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

Instrument that can measure the acoustic pressure and the sound beams shape

A

hydrophone AKA microprobe

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

What can a hydrophone measure

A

period, PRP, PRF, PD

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

Measures force the sound beam creates on any target it comes in contact with

A

radiation force

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

Based on the interaction of sound and light

A

acousto-optics

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

A shadowing system called a ______ allows us to view the shape of the sound beam in a medium

A

schlieren

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

What are the 3 devices that measure the output of the ultrasound transducer by absorption (conversion of sound energy into heat)

A

calorimeter, thermocouple, liquid crystals

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

Measures the total power in the entire sound beam through the process of absorption

A

calorimeter

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

Calculates the temp rise related to the power of the sound beam at specific locations

A

thermocouple

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

Crystals that change color based on their temp

A

liquid crystals

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

A primary mandate regarding clinical ultrasound is that the benefit to the patient must outweigh the risk of the exam

A

risk-benefit relationship

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

The science of identifying and measuring the characteristics of an ultrasound beam that are relevant to its potential for producing biological effects

A

dosimetry

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

Research performed within the living body

A

in vivo

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

Research performed outside the living body

A

in vitro

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

2 techniques used to syudy bioeffects

A

mechanistic approach, empirical approach

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

Begins as a proposal that a specific mechanism has the potential to produce bioeffects (CAUSE AND EFFECT)

A

mechanistic approach

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

Based on the acquisition and review of information from patients exposed to ultrasound (EXPOSURE AND RESPONSE)

A

empirical approach

18
Q

Mechanism proposes that bioeffects result from tissue temperature elevation

A

thermal

19
Q

Predictor of maximum temperature increase under most clinically relevant conditions

A

thermal index

20
Q

Thermal index is reported in what three ways

A

TIS, TIB, TIC

21
Q

Soft tissue thermal index

A

TIS

22
Q

Bone thermal index

A

TIB

23
Q

Cranial bone thermal index

A

TIC

24
Q

What absorbs more acoustic energy that soft tissue

A

bone

25
Q

Maximal heating is related to the beams _____ intensity

A

SPTA

26
Q

FDA regulator limit is

A

720W/cm^2

27
Q

Temperature elevation becomes progressively _____ from gray scale imaging to color doppler to spectral doppler

A

greater

28
Q

Non thermal consists of

A

radiation force and cavitation

29
Q

Exerted by a sound beam on tissues. Sheer stresses and streaming fluids can distort or disturb biologic structure

A

radiation force

30
Q

Interaction of sound waves with microscopic, stabilized, gas bubbles (gaseous nuclei) in the tissues

A

cavitation

31
Q

Occurs at lower mechanical index levels

A

stable cavitation

32
Q

With stable cavitation, gaseous nuclei tend to

A

oscillate (expand and contract)

33
Q

May occur at higher MI levels

A

transient cavitation

34
Q

Transient cavitation is

A

bubble bursting

35
Q

Transient cavitation produces what highly localized violent effects

A

colossal temperatures, shock waves

36
Q

Calculated number related to the likelihood of harmful bioeffects from cavitation

A

mechanical index

37
Q

What two sound wave characteristics is MI related to

A

peak rarefaction pressure, lower frequency

38
Q

Branch of medicine associated with population studied

A

epidemiology

39
Q

Best epidemiologic studied are

A

prospective, randomized

40
Q

Looking forward, protocol is established and specific information is systematically obtained

A

prospective

41
Q

One group exposed to ultrasound but not the other group

A

randomized

42
Q

AIUM conclusions

A

the benefit to the patient outweighs the risk, it is inappropriate to use diagnostic ultrasound in a non medical setting for entertainment

Vascular II & Physics II (21 decks)

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