Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
27 Cards in this Set
- Front
- Back
|
the single function of an AEC system is to eliminate the need to set what factor?
|
time
|
|
|
when using an AEC system, the radiographer loses control of _____
|
mAs
|
|
|
when mroe than one ionization chamber is used, what happens to the signal?
|
it is averaged
|
|
|
if the primary beam is collimated over an activated chamber, the radiograph would appear ____
|
dark
|
|
|
the x-ray generator must automatically terminate the AEC exposure when it reaches this mAs reading.
|
600
|
|
|
When using the AEC, the higher the mA setting, the _____ the time
|
shorter
|
|
|
increasing the mA setting when using AEC will ____ the radiographic density
|
not change
|
|
|
which of the following names the AEC detector that is located under the cassette?
|
Photomultiplier
|
|
|
moving from 0 to +1 density will do which of the following?
|
increase exposure time by 25%
|
|
|
a radiographer is performing an AP cervical spine. He has set an AEC technique and does not collimate the beam size. The resultant image will most likely possess what?
|
decreased density
|
|
|
which automatic exposure device works by converting x-ray photons first into light, then into an electronic signal?
|
Photomultiplier
|
|
|
Which AEC device works by using a gas filled chamber?
|
ionization chamebr
|
|
|
when using AEC, what should the radiographer adjust to manipulate the contrast fo the image?
|
KVp
|
|
|
when using AEC, what should the radiographer adjust to manipulate overall blackness of the image?
|
Density controls
|
|
|
What is the purpose of setting a backup timer?
|
Prevent excessive exposure to the patient
|
|
|
which of the following radiographic techniques would produce the greatest density?
-100 mA, 1/10 sec, 36" SID -200 mA, 3/10 sec, 36" SID -300 ma, 1/5 sec, 46" SID -50 ma, 1 sec, 44" SID |
200 mA, 3/10 sec, 36" SID
|
|
|
fluoroscopy mA range is commonly between what?
|
0.5-5.0 ma
|
|
|
During fluoroscopic image intensification, after the primary beam exits the patient, what will it interact with next?
|
input screen
|
|
|
the photocathod absorbs ___ and emits ____
|
light photons, electrons
|
|
|
electrostatic lenses are sued to accelerate and focus what/
|
electrons
|
|
|
the input screen absorbs _____ and emits ____
|
x-ray photons, light photons
|
|
|
the input screen is what shape?
|
concave
|
|
|
What is the best solution for quantum mottle?
|
increase fluoroscopic mA
|
|
|
the minimum source to skin distance for a stationary fluoroscopic unit is what?
|
15"
|
|
|
flux gain equals what?
|
# of output light photons / # of input x-ray photons
|
|
|
a radiographer has received a request for an examination that requires a 12:1 grid based upon patient thickness. the exposure technique chart suggests a non-grid technique of 6 mAs at 90 KVp. the required mAs with the grid will be
|
30 mAs
|
|
|
A particular radiograph was produced using 8 mAs and 84 KVp with an 8:1 ratio grid. The film is to be repeated using a 16:1 ratio grid. what should the new mAs be?
|
14 mAs
|
