Final Flashcards
How does collimating to a smaller area effect contrast?
Contrast is increased
Name two radiosensitive cells:
Lymphocyte and Sperm cells
State two factors that increase the probability that a photon will undergo a photoelectric absorption interaction:
Low energy (kVP) High atomic #
Dosimeter reports express occupationally exposed persons doses in _____ units.
REM
Increasing OFD _______ detail shapness.
Decreases
When collimating from a 14x17 area to an 8x10 area you would ________ mAs
Increase by 50%
Using oxidized developer ______ density and contrast.
Decreases
State two condition for using a bucky grid:
- Part greater than 10 cm
- kVp greater than 60
What is the purpose of using a bucky grid?
To reduce scatter radiation
State one of the purposes of the fixer solution.
- To clear the unexposed silver halide crystals off the film.
- To harden the gelatin emulsion
Where should a radiation dosimeter be worn?
On the collar, outside the apron.
To maintain radiographic density: If the mAs is decreased by 50% the kVp should be:
Increased by 15%
This technical factor controls the quantity of x-rays in the beam;
mAs (quantity/density)
Name 3 radiation protection devices:
- Filter collimator
- Intensifying screen
- Lead shield
- Lead apron
The developer solution converts silver halide to:
Black metallic silver
Define linearity:
The ability to manipulate “mA x sec.” for the same radiographic density.
State the charge that is on the focusing cup
Negative
This type of ionizing radiation can be stopped by the outer layers of the skin:
Alpha particles
State the two parts that make up the cathode:
- Focusing cup
- Filaments (long and short)
X-rays are produced by ______ current.
Direct (DC)
What does a rectifier do?
Converts AC to DC
How often must lead walls be replace?
Never
Assuming patient motion may be an issue, how should all mA and time setting be set?
Highest mA shortest exposure time
Assuming all other factors are constant, as exposure time increases, image density ________.
Increases
