Deck 3: Image Quality

Question 1

Which of the following terms also is referred to as the TP fraction?

A) Accuracy
B) Sensitivity
C) Specificity
D) None of the answer options are correct.

Answer 1

B
Sensitivity also is referred to as the TP fraction.

Question 2

If the bit depth of an MRI scanner is 12 bits, how many gray shades can be present in the image?

A) 1024
B) 2048
C) 4096
D) 8192

Answer 2

C
2¹² = 4096

Question 3

Which of the following can be thought of as the amount of information recorded in an image divided by the information available in the part?

A) Line spread function
B) Point spread function
C) Edge spread function
D) Modulation transfer function

Answer 3

D
Modulation transfer function is a numeric value that is used to measure the spatial resolution and is obtained from the LSF graph with a mathematic process known as Fourier transformation.

Question 4

Detective quantum efficiency (DQE) is a measure of which of the following?

A) contrast resolution
B) image noise
C) spatial resolution
D) x-ray absorption

Question 5

The amount of light either scattered or emitted by a surface is known as

A) luminance.
B) radiant flux.
C) luminous flux.
D) illuminance.

Question 6

Which of the following terms best describes the ability of an imaging system to create separate images of closely spaced high-contrast objects?

A) Screen speed
B) Spatial resolution
C) Contrast resolution
D) Quantum mottle

Question 7

Which of the following terms is the unit most commonly used to measure luminance?

A) Lux
B) Nit
C) Foot-candle
D) Lumen

Question 8

The type of contrast that is caused by variations in the tissue density within the anatomical part to be imaged, defines which of the following?

A) image contrast
B) subject contrast
C) inherent contrast
D) None of the answer options are correct.

Question 9

The ability of an imaging system to distinguish structures with similar x-ray transmission as separate entities is known as

A) contrast resolution.
B) spatial resolution.
C) temporal resolution.
D) spectral matching.

Question 10

Fifteen ft-cd would be equivalent to approximately ____ lux.

A) 100
B) 150
C) 160
D) 210

Question 11

Which modality generally display the greatest spatial resolution?

A) nuclear medicine
B) magnetic resonance imaging
C) DR radiographs
D) digital mammography

Question 12

The window width setting in a digital imaging system is used to manipulate which of the following values?

A) pixel brightness
B) spatial resolution
C) temporal resolution
D) image contrast

Question 13

A DR flat panel detector element (DEL) size will help to determine which of the following?

A) Contrast Resolution
B) Detective quantum efficiency (DQE)
C) spatial resolution
D) Dynamic range

Question 14

The rare earth phosphor, lanthanum oxybromide, emits what color of light?

A) Amber
B) Green
C) Blue
D) White