Digital Imaging
1. Which of the following would improve digital image quality?
a) Small matrix and large pixel size
b) Decreased pixel density and increased pixel pitch
c) Large matrix and large pixel size
d) Large matrix and increased pixel density
Ans:
D
2. The type of image receptor that uses a photostimulable phosphor to acquire the latent image is _______.
a) An intensifying screen
b) A flat-panel detector
c) Computed radiography
d) Radiographic film
Ans:
C
3. Which of the following is used to extract the latent image from an imaging plate?
a) Laser beam
b) Photomultiplier tube
c) Analog-to-digital converter
d) Thin-film transistor
Ans:
A
4. Which of the following will improve the quality of the digital image?
a) Decreased sampling frequency and increased sampling pitch
b) Decreased sampling frequency and decreased sampling pitch
c) Increased sampling frequency and increased sampling pitch
d) Increased sampling frequency and decreased sampling pitch
Ans:
D
5. Which of the following
would improve the quality of the digital image for a given field of view (FOV)?
a) A
fixed matrix size and larger imaging plate
b) A
decreased sampling frequency and larger imaging plate
c) A
small matrix size and larger pixel size
d) A
fixed matrix size and small imaging plate
Ans:
D
6. What is the process of
assigning a numerical value to represent a brightness value?
a) Dynamic
range
b) Signal-to-noise
ratio
c) Quantization
d) Spectral
sensitivity
Ans:
C
7. Which of the following pixel bit depths would display a greater range of shades of gray to represent anatomic tissues?
a) 8 Bit
b) 10 Bit
c) 14 Bit
d) 16 Bit
Ans:
D
8. Digital imaging
systems have a wide dynamic range.
a) True
b) False
Ans:
A
9. A lower
signal-to-noise ratio improves the quality of a digital image.
a) True
b) False
Ans:
B
10. Which of the
following is a measurement of the efficiency of an image receptor in converting
the x-ray exposure it receives to a quality radiographic image?
a) CNR
b) MTF
c) DQE
d) SNR
Ans:
C
11. Which of the
following is defined as a graphic representation of the pixel values?
a) Automatic
rescaling
b) Values
of interest
c) Histogram
d) Exposure
indicator
Ans:
C
12. What process is
employed to maintain consistent digital image brightness for overexposure or
underexposure?
a) Automatic
rescaling
b) Histogram
c) Exposure
indicator
d) Lookup
tables
Ans:
A
13. Which of the following is not a numerical value indicating the level of radiation exposure to a digital image receptor?
a) Sensitivity number
b) Exposure indicator
c) Window level
d) Exposure index
Ans:
C
14. What digital process alters image brightness and grayscale to improve the visibility of anatomic structures?
a) Automatic rescaling
b) Histogram analysis
c) Exposure indicator
d) Lookup tables
Ans:
D
15. What type of monitor passes light through liquid crystals to display a digital image?
a) TFT
b) LCD
c) CRT
d) PACS
Ans:
B
16. Maintaining a low level of ambient lighting can improve soft-copy viewing of digital images.
a) True
b) False
Ans:
A
17. Display monitors used for soft-copy viewing of digital images should have __________.
a) Increased ambient lighting
b) Decreased matrix size
c) Low spatial resolution
d) High luminance
Ans:
D
18. Which of the following is not a function during post-processing of a displayed digital image?
a) Automatic rescaling
b) Electronic masking
c) Windowing
d) Edge enhancement
Ans:
A
19. A wider window width __________.
a) Increases brightness
b) Decreases brightness
c) Increases contrast
d) Decreases contrast
Ans:
D
20. What is the communication standard for information sharing between PACS and imaging modalities?
a) DQE
b) DICOM
c) SMPTE
d) HL7
Ans:
B