1|Page
DIGITAL RADIOGRAPHY AND PACS TEST BANK 2025 - 2026
BY CARTER CHAPTER 1-9 QUESTIONS WITH ANSWERS AND
EXPLANATIONS LATEST VERSION
GRADED A+
Active-matrix flat-panel images (AMFPI) consist of a flat-panel array with an x-ray _________________
material
absorption
The two main types of x-ray absorption materials currently being used are
photoconductors and scintillators
materials that absorb x-rays, resulting in an electrical charge
photoconductors
phosphors that produce light when absorbing xrays
scintillators
True or False: An AMFPI detector measures the response of photoconductors and scintillators to xray
absorption and is a large area 2D array of pixels fastened to a thin glass backing, or substrate
true
the absorption material (photoconductor) is attacted to the AMFPI
electrically
the absorption material (scintillator/phosphor) is attached to the AMFPI
physically
True or False: the choice of xray absorption material determines whether the detector is direct or indirect
conversion
true
xray photons are absorbed by the coating material and immediately converted into an electrical signal
direct conversion
direct conversion uses photoconductors or scintillators
photoconductors
The photoconductor in direct conversion is usually made of
amorphous selenium (a-Se)
,2|Page
Amorphous selenium (photoconductor) in direct conversion absorbs the xrays and converts them to electrons
which are stored in the
TFT detectors
TFT is a photosensitive array made up of small pixels, also called a
detector element (del)
True or false: with direct conversion, each pixel contains a photodiode that absorbs the electrons and generates
electrical charges
true
isolates each pixel element and reacts like a switch to send the electrical charge to the image processor
field effect transistor (FET) or silicon TFT
More than _______________ pixels can be read and converted to a composite digital image in less than 1
second
1 million
high speed or low speed digital electronics are used to achieve fast image acquisition and processing
high speed
a two step process where xrays are converted into light, and then the light photons are converted to an electrical
signal
indirect conversion
phosphors used in indirect conversion, also known as the scintillator/phosphor layer
gadolinium oxysulphide (Gd2O2S) and thallium doped cesium iodide (CsI[TT])
gadolinium oxysulphide and cesium iodide
rapidly absorb xrays and produce light
True or false: the sintillation layer can either be structured or unstructured
true
unstructured layer produce more
scatted light
hygrogenated amorphous silicon (a-Si:H) is a
photodetector
gadolinium oxysulphide detecting material is made from small crystals bound together in an ____________ or
___________ layer along with a polyurethane material
,3|Page
unstructured, turbid
the most popular type of amorphous silicon detector uses a
CsI scintillator
the scintillator in a CsI, is made by growing very thin crystalline needles __________ to the detector surface
perpendicular
cesium iodide are considered a _______________ scintillator
structured
each pixel contains a
sensing component and switching component
what are the 2 types of switching components
2 contact switching diode and 3 contact TFT
what are the 2 ways to measure detector performance
numerical measurement of spatial resolution and DQE and observation of low-contrast objects in a contrast
phantom
how efficently a detector recieves exposure (input signal) and converts to a useful image (output signal)
detective quantum efficiency
a mathematical theorem, the ability to record spatial frequencies, ability to record detail
modulation transfer function
True or false: there is a possibility in any imaging system of losing or misrepresenting image information
because of defects in the operation components of the device
true
image artifacts can be caused by _______________ in the detector
malfunctions
true or false: the amount of dead pixels increase with the age of the of the detector
true
______________ programs may "fill in" dead pixels
software
true or false: Image artifacts include malfunctioning pixels, dead pixels, dust scratches, static discharge, and
chemical corrosion
true
, 4|Page
to remove the potential of having that artifact interfere with diagnosis
gain calibration or flat fielding
gain calibration ____________ the pixels included in the artifact
masks
if an image is taken prior to the detector releasing all of the signal from the previous image, a faint image of the
previous exposure may be visible
image lag
Image lag is almost like
double exposure
In both photostimulable phosphor (PSP) and flat-panel detector systems (FPD), after the x-ray photons have
been converted into ___________, these signals are available for processing and manipulation.
electrical
Preproccessing
Takes place in the computer where the algorithms determine the image histogram
Postprocessing
Done by the technologist through various user functions
In image formation, using values at the extreme high and low ends of the exposure range would result in a........
low-density resolution
*To avoid this, exposure data recognition processes only the optimal density exposure range.
Data recognition program searches for anatomy recorded on the imaging plate such as
1. Finding collimator edges
2. Eliminating scatter outside collimation
Information within the collimated area is the signal used for image data. This is the source for a __________-
____________ exposure data indicator.
vendor-specific
Failure of the system to find the collimation edges can result in.......
incorrect data collection
Equally important is centering anatomy to the center of the imaging plate. Ensures that appropriate recorded
densities are located. Failure to do so could result in an image that is..............
too bright or too dark
DIGITAL RADIOGRAPHY AND PACS TEST BANK 2025 - 2026
BY CARTER CHAPTER 1-9 QUESTIONS WITH ANSWERS AND
EXPLANATIONS LATEST VERSION
GRADED A+
Active-matrix flat-panel images (AMFPI) consist of a flat-panel array with an x-ray _________________
material
absorption
The two main types of x-ray absorption materials currently being used are
photoconductors and scintillators
materials that absorb x-rays, resulting in an electrical charge
photoconductors
phosphors that produce light when absorbing xrays
scintillators
True or False: An AMFPI detector measures the response of photoconductors and scintillators to xray
absorption and is a large area 2D array of pixels fastened to a thin glass backing, or substrate
true
the absorption material (photoconductor) is attacted to the AMFPI
electrically
the absorption material (scintillator/phosphor) is attached to the AMFPI
physically
True or False: the choice of xray absorption material determines whether the detector is direct or indirect
conversion
true
xray photons are absorbed by the coating material and immediately converted into an electrical signal
direct conversion
direct conversion uses photoconductors or scintillators
photoconductors
The photoconductor in direct conversion is usually made of
amorphous selenium (a-Se)
,2|Page
Amorphous selenium (photoconductor) in direct conversion absorbs the xrays and converts them to electrons
which are stored in the
TFT detectors
TFT is a photosensitive array made up of small pixels, also called a
detector element (del)
True or false: with direct conversion, each pixel contains a photodiode that absorbs the electrons and generates
electrical charges
true
isolates each pixel element and reacts like a switch to send the electrical charge to the image processor
field effect transistor (FET) or silicon TFT
More than _______________ pixels can be read and converted to a composite digital image in less than 1
second
1 million
high speed or low speed digital electronics are used to achieve fast image acquisition and processing
high speed
a two step process where xrays are converted into light, and then the light photons are converted to an electrical
signal
indirect conversion
phosphors used in indirect conversion, also known as the scintillator/phosphor layer
gadolinium oxysulphide (Gd2O2S) and thallium doped cesium iodide (CsI[TT])
gadolinium oxysulphide and cesium iodide
rapidly absorb xrays and produce light
True or false: the sintillation layer can either be structured or unstructured
true
unstructured layer produce more
scatted light
hygrogenated amorphous silicon (a-Si:H) is a
photodetector
gadolinium oxysulphide detecting material is made from small crystals bound together in an ____________ or
___________ layer along with a polyurethane material
,3|Page
unstructured, turbid
the most popular type of amorphous silicon detector uses a
CsI scintillator
the scintillator in a CsI, is made by growing very thin crystalline needles __________ to the detector surface
perpendicular
cesium iodide are considered a _______________ scintillator
structured
each pixel contains a
sensing component and switching component
what are the 2 types of switching components
2 contact switching diode and 3 contact TFT
what are the 2 ways to measure detector performance
numerical measurement of spatial resolution and DQE and observation of low-contrast objects in a contrast
phantom
how efficently a detector recieves exposure (input signal) and converts to a useful image (output signal)
detective quantum efficiency
a mathematical theorem, the ability to record spatial frequencies, ability to record detail
modulation transfer function
True or false: there is a possibility in any imaging system of losing or misrepresenting image information
because of defects in the operation components of the device
true
image artifacts can be caused by _______________ in the detector
malfunctions
true or false: the amount of dead pixels increase with the age of the of the detector
true
______________ programs may "fill in" dead pixels
software
true or false: Image artifacts include malfunctioning pixels, dead pixels, dust scratches, static discharge, and
chemical corrosion
true
, 4|Page
to remove the potential of having that artifact interfere with diagnosis
gain calibration or flat fielding
gain calibration ____________ the pixels included in the artifact
masks
if an image is taken prior to the detector releasing all of the signal from the previous image, a faint image of the
previous exposure may be visible
image lag
Image lag is almost like
double exposure
In both photostimulable phosphor (PSP) and flat-panel detector systems (FPD), after the x-ray photons have
been converted into ___________, these signals are available for processing and manipulation.
electrical
Preproccessing
Takes place in the computer where the algorithms determine the image histogram
Postprocessing
Done by the technologist through various user functions
In image formation, using values at the extreme high and low ends of the exposure range would result in a........
low-density resolution
*To avoid this, exposure data recognition processes only the optimal density exposure range.
Data recognition program searches for anatomy recorded on the imaging plate such as
1. Finding collimator edges
2. Eliminating scatter outside collimation
Information within the collimated area is the signal used for image data. This is the source for a __________-
____________ exposure data indicator.
vendor-specific
Failure of the system to find the collimation edges can result in.......
incorrect data collection
Equally important is centering anatomy to the center of the imaging plate. Ensures that appropriate recorded
densities are located. Failure to do so could result in an image that is..............
too bright or too dark
