AEC Homework Assignment/ Chapter 13 Quiz

Question 1

The primary purpose of AEC is to:

a.) reduce patient exposure
b.) control the amount of radiation reaching the IR
c.) control image contrast
d.) eliminate the need for the radiographer to think critically

Answer 1

b.) control the amount of radiation reaching the IR

Question 2

AEC controls the amount of radiation reaching the IR by controlling the:

a.) time of exposure
b.) mA
c.) kVp
d.) none of the above

Answer 2

a.) time of exposure

Question 3

When using AEC, the radiographer is responsible for determining:

a.) kVp
b.) mAs
c.) exposure time

Answer 3

a.) kVp

Question 4

The predetermined level of radiation exposure needed to terminate the exposure when using AEC is set by:

a.) the radiologist
b.) the technologist
c.) the equipment service personnel
d.) the manufacturer

Answer 4

c.) the equipment service personnel

Question 5

The two types of detectors used in AEC are:

a.) image intensifiers and phototimers
b.) phototimers and ionization chambers
c.) ionization chambers and geiger counters

Answer 5

b.) phototimers and ionization chambers

Question 6

The original type of AEC detector was the:

a.) ionization chamber
b.) geiger counter
c.) phototimer
d.) none of the above

Answer 6

c.) phototimer

Question 7

Todays AEC system is most likely to use an:

a.) ionization chamber
b.) geiger counter
c.) phototimer
d.) none of the above

Answer 7

a.) ionization chamber

Question 8

There is typically a configuration of at least ___________ AEC detectors in place.

a.) 2
b.) 3
c.) 4
d.) 5

Answer 8

b.) 3

Question 9

The device that converts the light energy to an electrical signal is the:

a.) photodiode
b.) photocathode
c.) photomultiplier
d.) A and C
e.) B and C

Answer 9

d.) A and C

Question 10

Phototimer AEC detectors are usually exit type devices because:

a.) the xrays must exit the patient to get to the detectors
b.) the xrays must exit the gird to get to the detectors
c.) the xrays must exit the image receptor to get to the detectors

Answer 10

c.) the xrays must exit the image receptor to get to the detectors

Question 11

An ionization chamber is a hollow cell that contains:

a.) water
b.) lead
c.) tungsten
d.) air

Answer 11

d.) air

Question 12

Ionization chambers AEC detectors are entrance type devices because the xrays must:

a.) enter the detector after passing through the IR
b.) enter the detector before entering the patient
c.) enter the detector before getting to the IR

Answer 12

c.) enter the detector before getting to the IR

Question 13

When xrays enter the ionization chamber

a.) atoms become ions
b.) atoms give up electrons
c.) electrons and positive ions become electricity
d.) all of the above

Answer 13

d.) all of the above

Question 14

The shortest expousure time that a radiographic tube with AEC can have is the:

a.) mAs readout
b.) back up time
c.) minimum response time
d.) density controls

Answer 14

c.) minimum response time

Question 15

The maximum length of time that an exposure lasts when using AEC is the:

a.) mAs readout
b.) back up time
c.) minimum response time

Answer 15

b.) back up time

Question 16

The actual amount of exposure used for an image when AEC is being used is the :

a.) mAs readout
b.) back up time
c.) minimum response time
d.) density controls

Answer 16

a.) mAs readout

Question 17

These can be adjusted to increase or decrease the amount of radiation needed to terminate the exposure using AEC:

a.) mAs readout
b.) back up time
c.) minimum response time
d.) density controls

Answer 17

d.) density controls

Question 18

When using AEC, the kVp:

a.) is set higher than usual
b.) is set lower than usual
c.) is set as appropriate for the study
d.) is determined by the AEC system

Answer 18

c.) is set as appropriate for the study

Question 19

Using a higher kVp during an AEC examination results in:

a.) a longer exposure time
b.) a shorter exposure time
c.) increased patient exposure
d.) B and C

Answer 19

b.) a shorter exposure time

Question 20

Using a lower mA station during an AEC examination results in:

a.) reduced patient exposure
b.) increased exposure time
c.) decreased exposure time
d.) A and B

Answer 20

b.) increased exposure time

Question 21

In imaging a child, a short exposure time is needed for an examination using AEC. The mA setting should:

a.) be low
b.) be mid range
c.) be high
d.) it doesnt matter- the AEC device will control the exposure time

Answer 21

c.) be high

Question 22

The AEC minimum response time may pose a probelm when:

a.) a long exposure time is needed
b.) the patient can easily hold still for the exposure
c.) the patient is unable to hold still for the exposure
d.) all of the above

Answer 22

c.) the patient is unable to hold still for the exposure

Question 23

The reason to have a back up timer is to:

a.) protect the patient from excessive exposure
b.) make sure the right mAs is used
c.) keep the tube from excessive heat loading
d.) A and C

Answer 23

d.) A and C

Question 24

If the back up time is set by the eqipment, the exposure time should end when the mAs reaches

a.) 100
b.) 400
c.) 600
d.) 1000

Answer 24

c.) 600

Question 25

When the radiographer has the oppurtunity to set the back up time, it should be approximately __________ of the expected exposure time. a.) 50 % b.) 150% c.) 250 % d.) 600 %

Answer 25

b.) 150%

Question 26

If the back up time is shorter than the actual exposure time needed for a properly exposed image a.) the image receptor will be overexposed b.) the image receptor will be underexposed c.) the exposure will be appropriate

Answer 26

b.) the image receptor will be underexposed

Question 27

The detector selected for an image should be: a.) the center detector because that is where the central ray is going b.) the two or three detectors that are covered by the part being imaged c.) theo ones that are superimposed by the anatomic structure of interest d.) all three so that the system can work properly

Answer 27

c.) the ones that are superimposed by the anatomic structure of interest

Question 28

If the radiorgapher is doing an upright chest using AEC but the table bucky is selected a.) the back up time will be reached b.) the patient will be exposed to excessive radiation c.) the IR will be over exposed d.) all of the above

Answer 28

d.) all of the above

Question 29

WHich of the following is the most critical aspect of successfully performing an examination using AEC? a.) centering the anatomy of interest over the detector b.) using the right mA c.) using the right kvp d.) setting the best back up time

Answer 29

a.) centering the anatomy of interest over the detector

Question 30

IF the AEC detectors are not completely covered by the part being imaged and are exposed to primary radiation a.) the patient will be overexposed b.) the exposure will terminate very quickly c.) the IR will be exposed to the appropriate amount of radiation d.) none of the above

Answer 30

b.) the exposure will terminate very quickly

Question 31

Performing a KUB on a beratric patient, using AEC results in: a.) underexposure to the IR b.) overexposure to the IR c.) appropriate exposure to the IR

Answer 31

c.) appropriate expsoure to the IR

Question 32

When there is a significant amount of scatter radiation reaching the detector the exposure time will: a.) be shorter than needed b.) be appropriate c.) be longer than needed

Answer 32

a.) be shorter than needed

Question 33

When using AEC, destructive pathologic conditions can cause a.) overexposure b.) underexposure c.) excessive overexposure

Answer 33

b.) underexposure

Question 34

Anatomically programmed radiography (APR) is a system in which the radigrapher selects a.) AEC setting b.) mAs and KVP settings c.) preset settings based on the part being imaged d.) preset settings based on the size of the patient

Answer 34

c.) preset settings based on the part being imaged

Question 35

When using AEC with digital imaging, errors resulting in overexposure to the IR result in (choose all that apply) a.) images that are dark b.) images with appropriate brightness c.) overexposed patients

Answer 35

c.) overexposed patients

Question 36

Using the plus or minus density controls should be done frequently to produce optimal images with AEC. a.) true b.) false

Answer 36

b.) false

Question 37

With digital imaging using AEC, if an AP thoracic spine is imaged with the central ray passing 3 inches to the right of the spine, the brightness in the area of interest is _______________ and the exposure time is ________________. (assume all other factors are normal.) a.) light, long b.) light, short c.) appropriate, short d.) dark, long

Answer 37

c.) appropriate, short

Question 38

Pre established guidelines used by the radiographer to select standarized normal or AEC exposure factors for each type of radiographic examination are called: a.) anatomical programming b.) exposure technique charts c.) mA reciprocity d.) quantam noise detectors

Answer 38

b.) exposure technique charts

Question 39

__________________ identifies optimal kVp values and alters the mAs for variations in part thickness. a.) fixed kvp varibale mas b.) variable kvp fixed mas c.) a and b

Answer 39

a.) fixed kvp variable mas

Question 40

Which of the following patient conditions require a change is technical factors? a.) plaster casts b.) additive disease c.) destrucitve disease d.) use of contrast media e.) all of the above

Answer 40

e.) all of the above

Question 41

What is the biggest reason for under or over exposure to the patient, IR and image when using AEC?

Answer 41

incorrect centering or positioning