Radiographic Technique

Question 1

Associated with penetration and quality of x-rays

Answer 1

kVp

Question 2

Controls image contrast

Answer 2

kVp

Question 3

Associated with quantity of x-rays

Answer 3

mAs

Question 4

Controls density of radiographic image

Answer 4

mAs

Question 5

Responsible for patient exposure

Answer 5

mAs

Question 6

3 primary exposure factors

Answer 6

kVp, mA, exposure time

Question 7

Higher kVp = [higher/lower] contrast

Answer 7

Lower

Question 8

Increasing kVp 15% has the same effect as ___ your mAs

Answer 8

doubling

Question 9

Measures mAs to SID ratio (exposure maintenance formula)

Answer 9

Direct Square Law

Question 10

3 types of filtration:

Answer 10

inherent, added, compensating

Question 11

Affects sharpness of image/spatial resolution

Answer 11

focal spot size

Question 12

As focal spot size increases, unsharpness [increases/decreases] and spatial resolution [increases/decreases]

Answer 12

increases; decreases

Question 13

As focal spot size decreases, unsharpness [increases/decreases] and spatial resolution [increases/decreases]

Answer 13

decreases; increases

Question 14

Most common technique chart

Answer 14

fixed kVp, variable mAs

Question 15

Controls exposure time

Answer 15

AEC

Question 16

Two types of radiation measuring devices

Answer 16

Phototimers, ionization chamber

Question 17

Once a predetermined amount of radiation is transmitted through a patient to the AEC detector, which of the following occurs?

Answer 17

The x-ray exposure terminates.

Question 18

Which automatic exposure device works by using a gas-filled chamber?

Answer 18

Ionization chamber

Question 19

Which automatic exposure device works by converting x-ray photons first into light and then into an electronic signal?

Answer 19

Phototimer

Question 20

Which exposure variable is controlled by the automatic exposure control device?

Answer 20

Seconds

Question 21

When using AEC, what should the radiographer adjust to manipulate the subject contrast of the image?

Answer 21

kVp

Question 22

What is the purpose of setting a backup time/mAs?

Answer 22

To prevent excessive exposure of the patient

Question 23

Which of the following is a system that allows the radiographer to select a specific button on the control panel that represents an anatomic area and displays a preprogrammed set of exposure factors?

Answer 23

Anatomically programmed technique

Question 24

In order to become familiar with manual technical factors (i.e., setting mAs and kVp and not using AEC), it is very helpful to pay attention to the:

Answer 24

mAs readout

Question 25

Ensures consistent image quality and to reduce the repeat imaging because of technique error and, in turn, reduce the patient exposure

Answer 25

technique chart

Question 26

When using a fixed kVp-variable mAs technique chart, if part thickness increases by 5 cm, what needs to happen to the mAs?

Answer 26

It should be doubled

Question 27

As mAs increases, the quantity of radiation reaching the IR:

Answer 27

Increases

Question 28

Which of the following technical factors affects the exposure to the IR by altering the amount and penetrating ability of the x-ray beam?

Answer 28

kVp

Question 29

In order to reduce patient exposure, what exposure factors should be considered?

Answer 29

higher kVp, lower mAs

Question 30

For every _____ of part thickness, the radiographer should adjust the mAs by a factor of two.

Answer 30

4 to 5 cm

Question 31

T/F: Changes in kVp do not affect the exposure indicator value.

Answer 31

False

Question 32

As mAs increases, the quantity of radiation reaching the IR:

Answer 32

increases

Question 33

In order to reduce patient exposure, what exposure factors should be considered?

Answer 33

high kVp, low mAs

Question 34

How much change in kVp will change the radiation exposure to the IR by a factor of 2?

Answer 34

15%

Question 35

Where is the radiographic grid located?

Answer 35

Between the patient and the IR

Question 36

T/F: Changes in kVp do not affect the exposure indicator number

Answer 36

False

Question 37

T/F: The same mAs and kVp should be used on an AP lumbar spine and a lateral lumbar spine radiograph

Answer 37

False

Question 38

What will limit the volume of tissue irradiated?

Answer 38

Cone and collimator

Question 39

Which grid design is manufactured to match the divergence of the x-ray beam

Answer 39

Focused grid

Question 40

Once a predetermined amount of radiation reaches the AEC detector, what occurs?

Answer 40

The exposure is stoppped

Question 41

When using AEC, what should the technologist use to adjust subject contrast on the image?

Answer 41

kVp

Question 42

A common cause for repeating images done with AEC is innacurate:

Answer 42

centering

Question 43

Accurate patient measurement is most critical with which chart?

Answer 43

variable kVp, fixed mAs

Question 44

T/F: AEC can be used with tabletop exams

Answer 44

False

Question 45

T/F: Technique charts are not needed if using AEC

Answer 45

False

Question 46

AEC devices work by measuring:

Answer 46

radiation that exits the patient

Question 47

How many detectors are typically found in an AEC system?

Answer 47

3

Question 48

Ionization chamber systems measure radiation [before/after] it interacts with the IR.

Answer 48

before

Question 49

The purpose of a backup timer is to:

Answer 49

limit unnecessary x-ray exposure

Question 50

What detector(s) should be selected for a right AP shoulder when the patient is supine on the x-ray table?

Answer 50

Center detector only

Question 51

The purpose of anatomically programmed techniques is to:

Answer 51

present the radiographer with a preselected set of exposure factors

Question 52

When using AEC with digital imaging systems, assuming all other factors are correct, selecting the center detector on a PA chest image results in:

Answer 52

increased exposure in the lung area

Question 53

The exposure indicator value reflects excessive exposure to the IR. Which of the following is the best for correcting the exposure error?

Answer 53

Decrease mAs by 50%

Question 54

What exposure factor affects both the quality and the quantity of the x-ray beam?

Answer 54

kVp

Question 55

Which of the following is not affected by kilovoltage?

Answer 55

Spatial resolution

Question 56

Increasing the mAs has __________ effect on brightness displayed in digital imaging.

Answer 56

No

Question 57

Which of the following would maintain radiation exposure to the IR when the kilovoltage is decreased by 15%?

Answer 57

Double the mAs

Question 58

What exposure factor change is recommended to maintain radiation exposure to the IR when increasing the patient thickness by 5 cm?

Answer 58

Double the mAs

Question 59

T/F: An additive pathological disease may require less kVp to maintain adequate exposure to the IR

Answer 59

False

Question 60

T/F: When exposure factors are selected using anatomically programmed technique, the variables should not be adjusted.

Answer 60

False

Question 61

Generally speaking, patient dose will be decreased with the ____ kVp -____ mAs chart

Answer 61

fixed; variable

Question 62

Accurate patient measurement is most critical for the ____ kVp -____ mAs chart

Answer 62

variable; fixed

Question 63

What is the purpose of a technique chart?

Answer 63

to ensure consistent image quality and to reduce the repeat imaging because of technique error and, in turn, reduce the patient exposure

Question 64

Exposure time will ______ when using AEC when patient thickness decreases.

Answer 64

decrease

Question 65

If the backup time/mAs is automatically set by the x-ray unit, the exposure should end when a maximum of _________ has been reached.

Answer 65

600 mAs

Question 66

The product of milliamperage and exposure time is ______ proportional to the quantity of x-rays produced

Answer 66

directly

Question 67

The original technique is 50 mA at 0.20 s. Which of the following exposure techniques will maintain the same exposure to the IR? a. 100 mA at 0.10 s and 400 mA at 25 ms b. 100 mA at 0.10 s and 200 mA at 0.05 s c. 200 mA at 0.05 s and 400 mA at 25 ms d. All options are correct

Answer 67

D

Question 68

The numerical value that is displayed on the processed image to indicate the level of x-ray exposure received on the digital image receptor is the___________

Answer 68

exposure indicator

Question 69

If lower than needed kVp is selected, the digital image will have: a. higher subject contrast and decreased brightness b. decreased brightness and increased quantum noise c. all options are correct d. higher subject contrast and increased quantum noise

Answer 69

D

Question 70

Decreasing collimation results in: a. lower image contrast and increased patient exposure b. increased fog and increased patient exposure c. all options are correct d. increased fog and lower image contrast

Answer 70

C

Question 71

T/F: Negative contrast agents increase the attenuation of the x-ray beam.

Answer 71

False

Question 72

The detectors selected for an image should be:

Answer 72

the ones that are superimposed by the anatomic structure of interest

Question 73

Using a higher kVp during an AEC examination results in:

Answer 73

A shorter exposure time

Question 74

T/F: Using the plus or minus density controls should be done frequently to produce optimal images with AEC

Answer 74

False