Radiography Imaging 2 Final Exam
with Complete Solutions
________ is considered the ideal expression of a digital detector's image resolution. It is
really the measure of how well the system preserves the signal contrast of the detector.
- correct Answer-modulation transfer function (MTF)
An expression of the ability of an image intensifier tube to convert x-ray energy into light
energy and increase the brightness of the image in the process is the - correct Answer-
brightness gain
AP thoracic spine is imaged using an outside instead of center detector, the brightness
in the area of interest will be _________________ and the patient will be
underexposed. - correct Answer-Appropriate
As compared with the H&D curve of film with the toe, straight-line portion, and shoulder,
the response of a digital IR to exposure is - correct Answer-straight line
Automatic exposure rate control (AERC) is used in digital fluoroscopy and is similar to
automatic brightness control (ABC). - correct Answer-True
Bit depth: - correct Answer-is the available grayscale and refers to the number of
shades of gray that can be displayed within a pixel.
DQE is - correct Answer-- evaluated by comparing the image noise of a detector with
that of an "ideal" detector with the same signal-response characteristics
- a measure of how well the signal-to-noise ratio (SNR) is preserved in an image
During an exam, patient dose is increased with - correct Answer-Repeats, inappropriate
AEC selection, the use of positive density control, the addition of positive contrast media
within the patient
During digital subtraction techniques, overlying structures such as bone and soft tissue
are removed from the subtracted image, so the vasculature is better visualized. - correct
Answer-True
Following the detection of the light released from the phosphor layer, the amplified
signal is sent to the _____________ to convert it to a digital electronic signal for the
display computer - correct Answer-analog-to-digital converter (ADC)
, If a shoulder examination is done using an 8:1 ratio grid and 12 mAs, how much mAs
should be used if the examination must be done tabletop (no grid)? - correct Answer-3
mAs
If a shoulder examination is done using an 8:1 ratio grid and 12 mAs, how much mAs
should be used if the examination must be done tabletop (no grid)? - correct Answer-3
mAs
In LCD monitors, the liquid crystal layer sandwiched between polarizing layers contains
crystals that are in an ________ state, but become __________ when electric current is
applied. - correct Answer-unorganized and twisted; organized and untwisted
Increased collimation means:
1. Decreased field size
2. Increased field size
3. Less volume of tissue irradiated - correct Answer-decreased field size and less
volume of tissue irradiated only
Increased collimation means:
1. Decreased field size
2. Increased field size
3. Less volume of tissue irradiated - correct Answer-decreased field size and less
volume of tissue irradiated only
Magnification of the fluoroscopic image results in improved (select all that apply): -
correct Answer-spatial resolution, contrast resolution
On the histogram, the _____ represents the amount of exposure and the _____ the
incidence of pixels for each exposure level - correct Answer-x-axis and y-axis
One limitation with the Image Intensifier is that ________ occurs, the loss of brightness
at the periphery of the image. However, this is eliminated with the use of flat-panel
detectors. - correct Answer-vignetting
Put the following sequence of events in this indirect capture system in order
1. The CCD converts the energy to an electronic signal
2. The light energy is then transmitted to the CCD
3. X-rays are absorbed by the scintillator and converted to light
4. Electronic signal is sent to the computer work station for processing and display -
correct Answer-3, 1, 2, 4
Put the following sequence of events in this indirect capture system in order
1. The CCD converts the energy to an electronic signal
2. The light energy is then transmitted to the CCD
3. X-rays are absorbed by the scintillator and converted to light
with Complete Solutions
________ is considered the ideal expression of a digital detector's image resolution. It is
really the measure of how well the system preserves the signal contrast of the detector.
- correct Answer-modulation transfer function (MTF)
An expression of the ability of an image intensifier tube to convert x-ray energy into light
energy and increase the brightness of the image in the process is the - correct Answer-
brightness gain
AP thoracic spine is imaged using an outside instead of center detector, the brightness
in the area of interest will be _________________ and the patient will be
underexposed. - correct Answer-Appropriate
As compared with the H&D curve of film with the toe, straight-line portion, and shoulder,
the response of a digital IR to exposure is - correct Answer-straight line
Automatic exposure rate control (AERC) is used in digital fluoroscopy and is similar to
automatic brightness control (ABC). - correct Answer-True
Bit depth: - correct Answer-is the available grayscale and refers to the number of
shades of gray that can be displayed within a pixel.
DQE is - correct Answer-- evaluated by comparing the image noise of a detector with
that of an "ideal" detector with the same signal-response characteristics
- a measure of how well the signal-to-noise ratio (SNR) is preserved in an image
During an exam, patient dose is increased with - correct Answer-Repeats, inappropriate
AEC selection, the use of positive density control, the addition of positive contrast media
within the patient
During digital subtraction techniques, overlying structures such as bone and soft tissue
are removed from the subtracted image, so the vasculature is better visualized. - correct
Answer-True
Following the detection of the light released from the phosphor layer, the amplified
signal is sent to the _____________ to convert it to a digital electronic signal for the
display computer - correct Answer-analog-to-digital converter (ADC)
, If a shoulder examination is done using an 8:1 ratio grid and 12 mAs, how much mAs
should be used if the examination must be done tabletop (no grid)? - correct Answer-3
mAs
If a shoulder examination is done using an 8:1 ratio grid and 12 mAs, how much mAs
should be used if the examination must be done tabletop (no grid)? - correct Answer-3
mAs
In LCD monitors, the liquid crystal layer sandwiched between polarizing layers contains
crystals that are in an ________ state, but become __________ when electric current is
applied. - correct Answer-unorganized and twisted; organized and untwisted
Increased collimation means:
1. Decreased field size
2. Increased field size
3. Less volume of tissue irradiated - correct Answer-decreased field size and less
volume of tissue irradiated only
Increased collimation means:
1. Decreased field size
2. Increased field size
3. Less volume of tissue irradiated - correct Answer-decreased field size and less
volume of tissue irradiated only
Magnification of the fluoroscopic image results in improved (select all that apply): -
correct Answer-spatial resolution, contrast resolution
On the histogram, the _____ represents the amount of exposure and the _____ the
incidence of pixels for each exposure level - correct Answer-x-axis and y-axis
One limitation with the Image Intensifier is that ________ occurs, the loss of brightness
at the periphery of the image. However, this is eliminated with the use of flat-panel
detectors. - correct Answer-vignetting
Put the following sequence of events in this indirect capture system in order
1. The CCD converts the energy to an electronic signal
2. The light energy is then transmitted to the CCD
3. X-rays are absorbed by the scintillator and converted to light
4. Electronic signal is sent to the computer work station for processing and display -
correct Answer-3, 1, 2, 4
Put the following sequence of events in this indirect capture system in order
1. The CCD converts the energy to an electronic signal
2. The light energy is then transmitted to the CCD
3. X-rays are absorbed by the scintillator and converted to light
