Deck 22: Intensifying Screens and Film Screen Combinations

Question 1

Intensifying screens are used to

A)reduce patient radiation dose.
B)produce light photons.
C)amplify the incoming x-ray beam.
D)all of the above

Answer 1

all of the above

Question 2

The ability of the phosphor to emit as much light per x-ray photon interaction as possible is a measurement of the

A)brilliance.
B)spectral emission.
C)atomic number.
D)screen speed.

Answer 2

screen speed.

Question 3

Which one of the following is not related to resolution?

A)screen speed
B)crystal size
C)layer thickness
D)base material

Answer 3

base material

Question 4

Light emitted from a phosphor that continues after photon excitation ends is called

A)intensification.
B)fluorescence.
C)phosphorescence.
D)luminescence.

Question 5

When light is emitted from a phosphor instantaneously upon photon excitation, it is called

A)intensification.
B)fluorescence.
C)phosphorescence.
D)luminescence.

Question 6

Delayed phosphorescent emission is called

A)screen lag.
B)afterglow.
C)phosphor drag.
D)both a and b

Question 7

Paired intensifying screens are typically used with

A)dental film.
B)mammographic film.
C)single-emulsion film.
D)duplitized film.

Question 8

The protective layer of an intensifying screen is easily damaged by

A)excess light.
B)fingernails.
C)single-emulsion film.
D)screen cleaners.

Question 9

What percentage of the latent image is formed by x-ray photons?

A)100 percent
B)99 percent
C)50 percent
D)1 percent

Question 10

The precise wavelength of light emitted by the phosphor is termed the

A)spectral emission.
B)conversion efficiency.
C)conversion emission.
D)spectral efficiency.

Question 11

An important component of the base of an intensifying screen is

A)intensification speed.
B)uniform radiolucency.
C)even radiopacity.
D)none of the above

Question 12

An intensifying screen consists of all of the following components EXCEPT

A)base.
B)phosphor layer.
C)emulsion layer.
D)reflective layer.

Question 13

Intensifying-screen resolution is controlled all of the of the following phosphor characteristics EXCEPT

A)crystal size.
B)layer thickness.
C)concentration.
D)adhesion.

Question 14

The ability of a material to emit light in response to excitation is

A)intensification.
B)fluorescence.
C)phosphorescence.
D)luminescence.

Question 15

The active layer of the intensifying screen is the

A)base.
B)reflective layer.
C)protective layer.
D)phosphor layer.

Question 16

When a phosphor is struck by an x-ray photon, it will emit light

A)parallel to the angle of incidence.
B)perpendicular to the angle of incidence.
C)at a 45-degree angle to the angle of incidence.
D)in all directions.

Question 17

The rare-earth screens use phosphors with atomic numbers of

A)3 to 11.
B)12 to 27.
C)57 to 71.
D)98 to 131.

Question 18

Until the 1970s, the most commonly utilized phosphor in radiography was

A)calcium tungstate.
B)rare earths.
C)gadolinium.
D)lanthanum.

Question 19

What percentage of the latent image is formed by the light photons produced from the intensifying screen?

A)100 percent
B)99 percent
C)50 percent
D)1 percent

Question 20

The predominant type of interaction that takes place between the x-ray photon and the high-atomic-number phosphor of the intensifying screen is

A)photoelectric.
B)Compton.
C)pair production.
D)Bremsstrahlung.

Question 21

To increase the speed of an intensifying screen,

A)increase phosphor size.
B)decrease the phosphor layer thickness.
C)decrease phosphor concentration.
D)remove the reflective layer.

Question 22

Match the following choices with the correct statement as they relate to film-screen image receptor systems.
screen lag

A)CaWO₄
B)gadolinium oxysulfide:terbium activated
C)fluorescence
D)conversion efficiency
E)RS 100
F)MTF
G)artifact
H)phosphorescence
I)increases quantum mottle
J)line spread function
K)RS 400
L)lp/mm

Question 23

When an insufficient quantity of photons strikes the intensifying screen, ____ will appear on the film as graininess.

A)lagging speed
B)quantum mottle
C)shadowing
D)latitude

Question 24

Match the following choices with the correct statement as they relate to film-screen image receptor systems.
RS of 1600

A)CaWO₄
B)gadolinium oxysulfide:terbium activated
C)fluorescence
D)conversion efficiency
E)RS 100
F)MTF
G)artifact
H)phosphorescence
I)increases quantum mottle
J)line spread function
K)RS 400
L)lp/mm

Question 25

Of the choices below, which one will yield a radiographic image with the highest spatial resolution?

A)an image system with a MTF of 0.7
B)an image system with a MTF of 0.4
C)an image system with an average gradient of 2.0
D)an image system with an image density of 1.2

Question 26

A film screen system that possesses high latitude will

A)produce high contrast images.
B)require precise exposure techniques.
C)produce images with many gray shades.
D)all of the above

Question 27

Recorded detail is measured by all of the following EXCEPT

A)line spread function.
B)modulation transfer function.
C)line pairs per millimeter.
D)contrast sensitivity.

Question 28

Cassettes stored for extended periods of time should be stored

A)flat.
B)empty.
C)at temperatures approaching 100 ^$\circ$ F.
D)in a darkened room.

Question 29

Film screen system with high RS values tend to offer

A)high resolution.
B)lower patient dose.
C)greater exposure latitude.
D)all of the above

Question 30

Match the following choices with the correct statement as they relate to film-screen image receptor systems.
quantification of receptor system fidelity

A)CaWO₄
B)gadolinium oxysulfide:terbium activated
C)fluorescence
D)conversion efficiency
E)RS 100
F)MTF
G)artifact
H)phosphorescence
I)increases quantum mottle
J)line spread function
K)RS 400
L)lp/mm

Question 31

To eliminate quantum mottle,

A)increase kVp.
B)decrease mAs.
C)increase mAs.
D)increase KVp.

Question 32

Poor screen/film contact can produce

A)increased radiographic film density.
B)loss of resolution.
C)loss of contrast.
D)decreased screen efficiency.

Question 33

The speed of an imaging system depends upon the

A)thickness of the phosphor or silver halide layer.
B)crystal/phosphor size.
C)conversion efficiency of the crystal/phosphor.
D)all of the above

Question 34

Match the following choices with the correct statement as they relate to film-screen image receptor systems.
blue-emitting phosphor

A)CaWO₄
B)gadolinium oxysulfide:terbium activated
C)fluorescence
D)conversion efficiency
E)RS 100
F)MTF
G)artifact
H)phosphorescence
I)increases quantum mottle
J)line spread function
K)RS 400
L)lp/mm

Question 35

When selecting a film/screen combination, a principal consideration in the best choice is

A)image contrast and exposure latitude.
B)image contrast and resolution.
C)MTF and dose.
D)line pair resolution and MTF.

Question 36

Which film type is more sensitive to the entire range of rare-earth phosphor emissions?

A)blue sensitive
B)yellow sensitive
C)green sensitive
D)violet sensitive

Question 37

If an imaging system with an RS value of 200 requires an exposure of 12 mAs, switching to a system with RS 800 speed will

A)require 3 mAs.
B)require 48 mAs.
C)require a 15% increase in kVp.
D)improve image resolution.

Question 38

Using an imaging system of RS 300, the system sensitivity would be

A)0.43 mR.
B)2.34 mR.
C)96 mR.
D)300 mR.

Question 39

Match the following choices with the correct statement as they relate to film-screen image receptor systems.
green-emitting rare earth phosphor

A)CaWO₄
B)gadolinium oxysulfide:terbium activated
C)fluorescence
D)conversion efficiency
E)RS 100
F)MTF
G)artifact
H)phosphorescence
I)increases quantum mottle
J)line spread function
K)RS 400
L)lp/mm

Question 40

A blue-violet emitting screen used with a green sensitive film will yield

A)higher patient dose.
B)improved resolution.
C)increased radiographic film density.
D)all of the above

Question 41

Match the following choices with the correct statement as they relate to film-screen image receptor systems.
emission of light energy upon stimulation

A)CaWO₄
B)gadolinium oxysulfide:terbium activated
C)fluorescence
D)conversion efficiency
E)RS 100
F)MTF
G)artifact
H)phosphorescence
I)increases quantum mottle
J)line spread function
K)RS 400
L)lp/mm

Question 42

Match the following choices with the correct statement as they relate to film-screen image receptor systems.
non-clinical, extraneous information on the final image

A)CaWO₄
B)gadolinium oxysulfide:terbium activated
C)fluorescence
D)conversion efficiency
E)RS 100
F)MTF
G)artifact
H)phosphorescence
I)increases quantum mottle
J)line spread function
K)RS 400
L)lp/mm

Question 43

Match the following choices with the correct statement as they relate to film-screen image receptor systems.
reference value for system speeds

A)CaWO₄
B)gadolinium oxysulfide:terbium activated
C)fluorescence
D)conversion efficiency
E)RS 100
F)MTF
G)artifact
H)phosphorescence
I)increases quantum mottle
J)line spread function
K)RS 400
L)lp/mm