AEC Homework Assignment/ Chapter 13 Quiz Flashcards
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
b.) control the amount of radiation reaching the IR
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
a.) time of exposure
When using AEC, the radiographer is responsible for determining:
a.) kVp
b.) mAs
c.) exposure time
a.) kVp
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
c.) the equipment service personnel
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
b.) phototimers and ionization chambers
The original type of AEC detector was the:
a.) ionization chamber
b.) geiger counter
c.) phototimer
d.) none of the above
c.) phototimer
Todays AEC system is most likely to use an:
a.) ionization chamber
b.) geiger counter
c.) phototimer
d.) none of the above
a.) ionization chamber
There is typically a configuration of at least ___________ AEC detectors in place.
a.) 2
b.) 3
c.) 4
d.) 5
b.) 3
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
d.) A and C
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
c.) the xrays must exit the image receptor to get to the detectors
An ionization chamber is a hollow cell that contains:
a.) water
b.) lead
c.) tungsten
d.) air
d.) air
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
c.) enter the detector before getting to the IR
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
d.) all of the above
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
c.) minimum response time
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
b.) back up time
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
a.) mAs readout
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
d.) density controls
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
c.) is set as appropriate for the study
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
b.) a shorter exposure time
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
b.) increased exposure time
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
c.) be high
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
c.) the patient is unable to hold still for the exposure
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
d.) A and C
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
c.) 600
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 %
b.) 150%
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
b.) the image receptor will be underexposed
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
c.) the ones that are superimposed by the anatomic structure of interest
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
d.) all of the above
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
a.) centering the anatomy of interest over the detector
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
b.) the exposure will terminate very quickly
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
c.) appropriate expsoure to the IR
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
a.) be shorter than needed
When using AEC, destructive pathologic conditions can cause
a.) overexposure
b.) underexposure
c.) excessive overexposure
b.) underexposure
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
c.) preset settings based on the part being imaged
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
c.) overexposed patients
Using the plus or minus density controls should be done frequently to produce optimal images with AEC.
a.) true
b.) false
b.) false
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
c.) appropriate, short
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
b.) exposure technique charts
__________________ 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
a.) fixed kvp variable mas
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
e.) all of the above
What is the biggest reason for under or over exposure to the patient, IR and image when using AEC?
incorrect centering or positioning
