Brainscape's Knowledge GenomeTM

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


See full index

Science and Technology 1 > Factors Affecting Image Quality > Flashcards

Factors Affecting Image Quality Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What is image quality?

A

The optimal features of an image that allow us to effectively interpret an image

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

Why does the image need to be representative of the patient’s actual anatomy?

A

So that we can reduce any factors that could distort the image

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

What does the inverse-square law say?

A

The further we are from the source of radiation, the less radiation we ‘re exposed to

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

What happens to the density as the distance increases?

A

The density decreases

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

What happens to the dose when the distance increases?

A

The dose decreases

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

What is the SID?

A

The source to image distance (from x-ray tube to detector)

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

What is the OID?

A

The object to image distance (from patient to detector)

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

What is the SOD?

A

Source object distance (from x-ray tube to patient)

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

What is the SID also known as?

A

FRD

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

What is the OID also known as?

A

ORD

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

What is the SOD also known as?

A

FOD

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

What does FRD mean?

A

Focus to receptor distance (from x-ray tube to receptor)

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

What does ORD mean?

A

Object to receptor distance (from patient to receptor)

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

What does FOD mean?

A

Focus object distance

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

What continues to happen when the OID is increased?

A

The x-rays continue to go in another direction as they pass through the object

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

Will objects further or closer to the image receptor be magnified more?

A

Objects further away

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

Should the body part being imaged be close or far from the image receptor?

A

As close to the image receptor as possible

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

Why do we have to label if an image of the chest was taken AP instead of PA?

A

Because in AP, the heart will be magnified more than PA, so the radiologist knows that the increased size isn’t du to abnormalities- it’s due to positioning.

19
Q

When do we use AP for a chest x-ray?

A

If the patient can’t stand up against the wall bucky

20
Q

What is the purpose of getting the patient’s chest against the wall Bucky?

A

So we can get the heart as close to the imaging detector as possible

21
Q

What do we do to reduce the magnification?

A

Increase the SID

22
Q

What will happen to the intensity of the x-ray beam if the SID increases?

A

The intensity decreases

23
Q

If we change the SID, what factor do we have to change?

A

mAs

24
Q

What happens to the intensity in the x-ray beam if we increase the distance from the source?

A

The intensity decreases

25
Q

If you double the distance from the focus, the x-ray beam will be …. of its original intensity

A

1/4

26
Q

How can we get the same beam intensity at double the distance?

A

Increase the mAs

27
Q

In what direction should the object and image receptor be together?

A

Parallel

28
Q

In what direction should the central ray and the receptor be together?

A

Perpendicular

29
Q

What would happen if the object and receptor aren’t parallel, and if the central ray isn’t perpendicular to the receptor?

A

The image may be distorted

30
Q

Why might image distortion be done on purpose?

A

To display anatomy in a certain way, e.g. an oblique hand

31
Q

What are the consequences of the object not being parallel to the image receptor?
(3)

A

The image will be distorted

Different aspects of the image will be magnified

The object may be elongated or foreshortened, so fractures or pathologies could be missed

32
Q

What is the consequence of the central ray isn’t perpendicular to the image receptor?

A

The image will be distorted

33
Q

What factors can contribute to unsharpness in an image?
(2)

A

Patient movement

Focal spot size

34
Q

Does this chest x-ray have movement unsharpness or no movement unsharpness?

A

No movement unsharpness

35
Q

Does this chest x-ray have movement unsharpness or no movement unsharpness?

A

Movement unsharpness

36
Q

Is the focal point pre-set or do we have to set it up?

A

It should be pre-set

37
Q

What is the focus?

A

The area that’s bombarded by the x-rays

38
Q

What can the focus be altered to be?
(2)

A

Broad focal spot

Fine focal spot

39
Q

How many anodes does the cathode have?

A

2 anodes

40
Q

When imaging a larger body part, do we use a broader or finer focal spot?

A

Broader focal spot

41
Q

When imaging a smaller body part, do we use a broader or finer focal spot?

A

Finer focal spot

42
Q

What is the issue with using a larger focal spot size?

A

The larger the focal spot size, the larger the area of penumbra (unsharpness)

43
Q

What are the issues with using a finer focal spot size?
(2)

A

Finer focal spots are a more concentrated area, so more heat is produced, which could damage the anode

The image is also more susceptible to motion unsharpness

Science and Technology 1 (17 decks)

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