Brainscape's Knowledge GenomeTM

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


See full index

Physics 1 > Lesson 18 (Part 2) > Flashcards

Lesson 18 (Part 2) Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

Elevation resolution

A

Minimum reflector separation perpendicular to scan plane to produce separate echoes
- 3rd dimension

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

What does the beam have in elevation resolution?

A

Section thickness / elevational plane

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

What can elevation resolution produce?

A

A section thickness artifact

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

What is a section thickness artifact also known as?

A

Partial volume artifact

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

What do partial volume artifacts fill? (4)

A
  1. Cysts
  2. Gallbladder
  3. Vessels
  4. Bladder
  • anechoic structures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What will poor elevational resolution show?

A

Echoes from outside the intended scan plane

- especially within anechoic structures

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

How do we fix elevational resolution artifacts? (2)

A
  1. THI
    - harmonics
  2. Spatial compounding
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What THI is better for fixing elevation resolution artifacts?

A

Narrower and thinner beam

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

Why are narrower and thinner beams better for THI?

A

Less likely to pick up echoes from other planes

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

Spatial compounding

A

Scanning at different angles help to deal with anechoic structures

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

Temporal resolution

A

Being able to separate echoes in time

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

How is poor temporal resolution visualized?

A

As a lag

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

Contrast resolution

A

Being able to separate 2 different shades of grey

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

Is having more shades of gray better or worse in contrast resolution?

A

Better

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

What is the useful frequency range for diagnostic applications?

A

2-20 MHz

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

What do higher frequencies do? (2)

A
  1. Increase resolution

2. Decrease the maximum imaging depth

17
Q

What happens if you have less than 2MHz?

A

You are losing resolution/image quality

18
Q

What happens if you have more than 20MHz?

A

You will not penetrate as well

19
Q

How can focus be achieved?

A

In 3D (perpendicular to the scanning plane) with a lens or curved elements

20
Q

What does phasing need to be applied to focus the 3D electronically?

A

At least 3 rows of elements

21
Q

What does electronic focusing eliminates?

A

The need for the lens or curved elements

22
Q

What is 3D imaging?

A

Volume imaging

23
Q

What is the down side of 3D compared to 2D?

A

It lags

24
Q

What do 2D arrays have the ability to do?

A

Steer and focus in 2 dimensions

25
Q

What kind of image does 1D array produce?

A

2D imaging

26
Q

What kind of image does 2D array produce?

A

3D imaging

27
Q

Transmit steering

A

Sending pulses with a delay

28
Q

What are 2 other terms for 3D imaging?

A
  1. Volume imaging

2. Volumetric scanning

29
Q

What is 3D scanning mots common for?

A

Obstetrics

- breasts

30
Q

What makes up 4D imaging?

A

3D imaging + time

Physics 1 (42 decks)

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