Chapter 26 (Module 1)

Question 1

Assessment of digital radiographic image quality includes:
a. looking at the window/level values on the monitor
b. electronic masking the image to improve the exposure indicator value
c. postprocessing the image to enhance image contrast
d. referencing exposure indicators values for acceptance

Answer 1

Referencing exposure indicators values for acceptance

Question 2

Digital image artifacts such as vertical or horizontal lines, opaque, white lines demonstrates:
a. underexposure
b. excessive exposure
c. quantum noise
d. system noise

Answer 2

Excessive exposure

Question 3

The brightness of the image on a viewing monitor is
a. the result of receptor exposure.
b. the result of the tissue density.
c. the result of the tissue thickness.
d. a function of the monitor.

Answer 3

A function of the monitor

Question 4

The principal controlling factor of radiographic receptor exposure is
a. kVp.
b. mAs.
c. focal spot size.
d. filtration thickness.

Answer 4

mAs

Question 5

Which statement is TRUE?
a. As mAs increases, scatter decreases.
b. As mAs decreases, quantum noise can appear.
c. As mAs increases, remnant radiation decreases.
d. As mAs decreases, exposure increases logarithmically.

Answer 5

As mAs decreases, quantum noise can appear

Question 6

The minimum change necessary to improve the appearance of noise on a digital image is ____ percent of mAs.
a. 10–12
b. 25–35
c. 50–60
d. none of the above

Answer 6

25-35

Question 7

Which generator type produces the least amount of receptor exposure per mAs?
a. single-phase, 2-pulse
b. three-phase, 6-pulse
c. three-phase, 12-pulse
d. a high-frequency generator

Answer 7

Single-phase, 2-pulse

Question 8

Which generator produces the greatest amount of receptor exposure per mAs?
a. single-phase, 2-pulse
b. three-phase, 6-pulse
c. three-phase, 12-pulse
d. a high-frequency generator

Answer 8

A high-frequency generator

Question 9

Which rule is used as a guide to maintain the same receptor exposure, when kVp changes?
a. doubling rule
b. 15% rule
c. inverse square rule
d. density maintenance law

Answer 9

15% rule

Question 10

Which factor influences the number of photons reaching the IR?
a. kVp
b. mAs
c. focal spot selection
d. exposure time

Answer 10

mAs

Question 11

Which factor influences the number of photons reaching the IR?
a. kVp
b. mAs
c. focal spot selection
d. exposure time

Answer 11

mAs

Question 12

Which factor influences the average energy of photons reaching the IR?
a. kVp
b. mAs
c. focal spot size
d. mA

Answer 12

kVp

Question 13

The 15% rule will affect
a. recorded detail.
b. image brightness.
c. distortion.
d. none of the above.

Answer 13

None of the above

Question 14

The relationship between exposure and SID is
a. directly proportional.
b. inversely proportional to the cube of the distance.
c. directly proportional to the square of the distance.
d. inversely proportional to the square of the distance.

Answer 14

Inversely proportional to the square of the distance

Question 15

Moderate increases in kVp with a digital receptor, will produce
a. dramatic changes in image contrast.
b. a change in entrance skin exposure.
c. no change in image brightness.
d. both b and c.

Answer 15

Both b and c

Question 16

What conclusion can you reach regarding an image with an S# of 750 and good image brightness on the display monitor?
a. The image is likely to demonstrate noise or quantum mottle.
b. There was not enough exposure to create a good histogram.
c. The noise level will be at a minimum and the image will look good in the magnification mode.
d. The IR received too much exposure.

Answer 16

The image is likely to demonstrate noise or quantum mottle.

Question 17

You have completed a chest radiograph using 3 mAs @ 110 kVp. The image shows obvious under penetration of the mediastinal anatomy. The professional radiographer would
a. increase kVp by 3 kVp and repeat the exposure.
b. use the 15% Rule and reduce the kVp and increase the mAs.
c. increase the kVp to 120 kVp and repeat the exposure at the same mAs.
d. remove the beam filtration and repeat the exposure.

Answer 17

Increase the kVp to 120 kVp and repeat the exposure at the same mAs.

Question 18

In the event of making a single exposure that is critical to the exam success, most experienced technologists will
a. use slightly less mAs than necessary to prevent overexposure.
b. overexpose the IR slightly.
c. provide enough exposure to create an adequate histogram or permit viewing a film with a bright light.
d. both b and c.

Answer 18

Both b and c

Question 19

In the case of film radiography,
a. the response to exposure is linear.
b. the response to radiation exposure is inverse.
c. the response to exposure is logarithmic.
d. the response to exposure is exclusively a function of kVp.

Answer 19

The response to exposure is logarithmic

Question 20

Image brightness on an image display monitor is controlled by
a. window level.
b. window width.
c. EI number.
d. S number.

Answer 20

Window level

Question 21

The effect of mAs upon IR exposure is
a. inverse.
b. inversely proportional.
c. directly proportional.
d. dependent upon kVp.

Answer 21

Directly proportional

Question 22

Optimum exposure to a digital detector system
a. varies between manufacturers.
b. is a function of acceptable noise levels.
c. is identified with target exposure index values.
d. all of the above.

Answer 22

All of the above

Question 23

As you analyze your image, you come to the conclusion that it must have more exposure. As a general rule, you should increase
a. kVp.
b. mAs by 2X.
c. the SID.
d. mAs by a 0.5 multiplier.

Answer 23

mAs by 2X.

Question 24

A change in kVp, as an exposure factor, affects
a. average beam energy.
b. beam intensity.
c. the amount of scatter production.
d. all of the above.

Answer 24

All of the above

Question 25

The greatest factor in the production of scatter radiation is
a. kVp.
b. mAs.
c. patient thickness.
d. patient position.

Answer 25

Patient thickness

Question 26

Radiographic room A is a three-phase, six-pulse generator. Room B is a high-frequency generator. When going between these two rooms to perform examinations, what exposure modification is necessary to produce comparable exposure density?
a. Use 15 percent more with the three-phase system.
b. Use 10 percent more with the high-frequency system.
c. No change is required between the two systems.
d. Use 10 percent less with the high-frequency system.

Answer 26

No change is required between the two systems

Question 27

Focal spot blooming occurs with
a. high kVps.
b. high mA exposures.
c. large SIDs.
d. extreme tube angulation.

Answer 27

high mA exposures

Question 28

Because of the “heel effect,” x-ray beam intensity
a. is greater under the cathode side of the tube.
b. is greater under the anode side of the tube.
c. is equal across the beam long axis.
d. changes with patient position.

Answer 28

is greater under the cathode side of the tube

Question 29

The anode heel effect is more pronounced with
a. smaller field sizes (8” × 10”).
b. stationary anodes.
c. a 10− degree target angle.
d. rotating anodes.

Answer 29

a 10 degree target angle

Question 30

When changing your SID from 72” to 56”
a. decrease your kVp by 15 percent.
b. decrease your mAs by 50 percent.
c. increase the mAs by a factor of 4.
d. increase the kVp by 15 percent.

Answer 30

decrease your mAs by 50 percent

Question 31

All of the following will decrease digital receptor exposure EXCEPT
a. increased grid ratios.
b. increased beam angulation from 5 degrees to 10 degrees.
c. increased OID.
d. increased filtration.

Answer 31

increased beam angulation from 5 degrees to 10 degrees