111- Chapter 16,17,18 Test

Question 1

What can you do to exposure field size and tissue thickness to reduce scatter production

Answer 1

Decrease field size, compression band, PA

Question 2

Is pt thickness best reduced in the abdomen when the pt is supine or prone

Answer 2

Prone

Question 3

How is grid ratio determined

Answer 3

Height of lead strips / distance between strips

Question 4

For a given grid ratio, as height of strips increase, how does it effect scatter pickup

Answer 4

Increases

Question 5

For a given grid ratio, as distance between lead strips increases, how does it effect scatter pickup

Answer 5

Decreases

Question 6

Which type of grid is most challenging to use accurately

Answer 6

Cross hatched

Question 7

Define grid frequency

Answer 7

of lead strips per inch or cm

Question 8

Define grid selectivity

Answer 8

How much a grid allows the primary beam to transmit and how much scatter pickup

Question 9

Define K or contrast improvement factor

Answer 9

How well the grid cleaned up scatter and improved contrast

Question 10

What effect will imaging a thicker body part have on Compton and photoelectric interactions

Answer 10

Increase Compton decrease photoelectric

Question 11

What effect will imaging a thicker body part have on scatter production

Answer 11

Increase

Question 12

What effect will imaging a thicker body part have on image contrast

Answer 12

Decrease contrast

Question 13

When comparing a 5:1 grid and a 16:1, what prevents scatter the best

Answer 13

Neither

Question 14

When comparing a 5:1 grid and 16:1, which removes scatter the best

Answer 14

16:1

Question 15

When comparing a 5:1 grid and 16:1, which requires the biggest increase in technique

Answer 15

16:1

Question 16

When comparing a 5:1 grid and 16:1, which has the highest k factor

Answer 16

16:1

Question 17

When comparing a 5:1 grid and 16:1, which is more selective

Answer 17

16:1

Question 18

When comparing a 5:1 grid and 16:1, which requires more accurate positioning

Answer 18

16:1

Question 19

Describe the design of a focused grid in relationship to the Xray beam

Answer 19

Strips angle out to match divergence of beam

Question 20

What is the grid conversion factor formula

Answer 20

Mas 1 = GCF1

Mas2= GCF2

Question 21

What is the grid conversion factor for no grid

Answer 21

1

Question 22

What is the grid conversion factor for 5:1

Answer 22

2

Question 23

What is the grid conversion factor for 6:1

Answer 23

3

Question 24

What is the grid conversion factor for 8:1

Answer 24

4

Question 25

What is the grid conversion factor for 10:1

Answer 25

4.5

Question 26

What is the grid conversion factor for 12:1

Answer 26

5

Question 27

What is the grid conversion factor for 16:1

Answer 27

6

Question 28

What is grid cutoff and how can it occur

Answer 28

Undesired absorption of primary beam, off focus, level, center, upside down

Question 29

When should a grid be used

Answer 29

Body part greater than 9-10 cm. Kvp over 60

Question 30

How does air gap technique work in reducing scatter reaching IR and when might it come in handy

Answer 30

Greater OID drops off scatter, use when grid is unavailable

Question 31

How does an off level grid error occur when using a parallel grid

Answer 31

Short axis of grid is angled

Question 32

How does an off level grid error occur when using a focused grid

Answer 32

Short axis is angled

Question 33

How does an off center grid error occur when using a parallel grid

Answer 33

No error

Question 34

How does an off center grid error occur with a focused grid

Answer 34

Not centered on long axis

Question 35

How does an off focus grid error occur with a parallel grid

Answer 35

No error

Question 36

How does an off focus grid error occur when using a focused grid

Answer 36

When SID is out of focal range

Question 37

How does an upside down grid error occur when using a parallel grid

Answer 37

No error

Question 38

How does an upside down grid error occur when using a focused grid

Answer 38

Grid is upside down

Question 39

What causes the moiré grid error

Answer 39

When scanner frequency matches the grid frequency

Question 40

In the use of a focused grid, define grid radius

Answer 40

Distance from face of grid to convergence line

Question 41

In the use of a focused grid, define focal range

Answer 41

Range of SID that can be used with the grid

Question 42

What is the only type of grid error that occurs with both parallel and focused grids

Answer 42

Off level

Question 43

Which parts of a grid are radiopaque and radiolucent

Answer 43

Lead strips- radiopaque | Interspace- radiolucent

Question 44

What is the biggest variable a radiographer may face

Answer 44

Patient

Question 45

What factors may be increased in a patient with an additive pathological condition

Answer 45

Increase kvp by 5-15%

Question 46

Is an additive condition easier or more difficult for the beam to penetrate

Answer 46

More difficult

Question 47

What technical factors and how much are changed for destructive conditions

Answer 47

Decrease mas by 25-50%

Question 48

When comparing bone to fat, which one attenuates more of the beam

Answer 48

Bone

Question 49

When comparing bone to fat, which one has a higher atomic number

Answer 49

Bone

Question 50

When comparing bone to fat, which one has greater mass density

Answer 50

Bone

Question 51

When comparing bone to fat, which one provides greater radiographic contrast

Answer 51

Bone

Question 52

When comparing bone to fat, which one provides greater subject contrast

Answer 52

Bone

Question 53

How will increased OID affect subject detail

Answer 53

Decrease

Question 54

How will size of patient affect subject detail

Answer 54

Decrease

Question 55

How does a patients size and radiographic position affect size distortion in the form of magnification

Answer 55

Increase distortion

Question 56

Does Compton scatter contribute to diagnostic information of an image

Answer 56

No

Question 57

Does Compton scatter increase or decrease as tissue density increases

Answer 57

Decrease

Question 58

Does Compton scatter increase or decrease as patient thickness increases

Answer 58

Increase

Question 59

Does Compton scatter increase or decrease as volume of tissue increases

Answer 59

Increase

Question 60

Does Compton scatter increase or decrease as kvp increases

Answer 60

Increase

Question 61

Does Compton scatter increase or decrease radiographic contrast

Answer 61

Decrease

Question 62

Does Compton scatter increase or decrease density/IR exposure

Answer 62

Increase

Question 63

Does Compton scatter increase or decrease with an increase in atomic number

Answer 63

Decrease

Question 64

Does Compton scatter increase or decrease occupational dose

Answer 64

Increase

Question 65

What are the best ways to reduce the amount of scatter reaching the ir

Answer 65

Collimate, decrease kvp, use grid

Question 66

Transmitted radiation affects density/IR exposure how

Answer 66

Increases exposure

Question 67

How can the use of a compression band decrease tissue volume and subsequent scatter production

Answer 67

Push material down

Question 68

What is the main determining factor of how well a grid will be at improving contrast by removing scatter

Answer 68

Lead content

Question 69

Which direction do grid lines in the Bucky run in relation to the table and which way may the tube be angled

Answer 69

Long axis, cephalic or caudal

Question 70

When using a parallel grid there will always be some degree of grid cutoff. Where on the image will this be noticed

Answer 70

Lateral edges

Question 71

Is grid cutoff with a parallel grid more prevalent when using a long or short sid

Answer 71

Short

Question 72

With an off level grid error where on the image will cutoff be noticeable

Answer 72

Whole image

Question 73

With an off center grid error where on the image will the cutoff be noticeable

Answer 73

Whole image

Question 74

With an off focus grid error where on the image will the cutoff be noticeable

Answer 74

Edges

Question 75

With an upside down grid error where on the image will the cutoff be noticeable

Answer 75

Edges

Question 76

What is better for scatter cleanup: high or low frequency grid

Answer 76

Low frequency

Question 77

Subject density definition

Answer 77

Impact patient has on density/exposure

Question 78

Subject contrast definition

Answer 78

Degree of differential absorption in the body

Question 79

Subject detail definition

Answer 79

Dependent on structures position in the body in relationship to the Ir

Question 80

Subject distortion definition

Answer 80

Misrepresentation of size and shape of body part

Question 81

Additive or destructive: aerophagia

Answer 81

Destructive

Question 82

Additive or destructive: ascites

Answer 82

Additive

Question 83

Additive or destructive: atelectasis

Answer 83

Additive

Question 84

Additive or destructive: atrophy

Answer 84

Destructive

Question 85

Additive or destructive: bronchiectasis

Answer 85

Additive

Question 86

Additive or destructive: cirrhosis

Answer 86

Additive

Question 87

Additive or destructive: edema

Answer 87

Additive

Question 88

Additive or destructive: emphysema

Answer 88

Destructive

Question 89

Additive or destructive: empyema

Answer 89

Additive

Question 90

Additive or destructive: multiple myeloma

Answer 90

Destructive

Question 91

Additive or destructive: pneumonia

Answer 91

Additive

Question 92

Additive or destructive: osteoarthritis

Answer 92

Destructive

Question 93

Additive or destructive: osteochondroma

Answer 93

Additive

Question 94

Additive or destructive: osteomyelitis

Answer 94

Destructive

Question 95

Additive or destructive: sarcoma

Answer 95

Destructive

Question 96

Additive or destructive: sclerosis

Answer 96

Additive