Deck 16: Digital Radiography

Question 1

In digital radiography,the latent image is formed on the _____.

A) radiographic film
B) image matrix
C) radiation detector
D) computer screen

Answer 1

radiation detector

Question 2

In digital radiography,the brightness of the image is determined by _____.

A) pixel values
B) Hounsfield units
C) automatic brightness control
D) film contrast

Answer 2

pixel values

Question 3

Spatial resolution is determined by the ratio of _____ to _____.

A) matrix size, field of view
B) field of view, matrix size
C) bit depth, field of view
D) field of view, dynamic range

Answer 3

field of view, matrix size

Question 4

In digital fluoroscopy,each matrix pixel represents _____.

A) interface reflectivity
B) atomic number and mass density
C) proton density and spin relaxation
D) radionuclide uptake

Question 5

Digital imaging techniques are always applied to _____.

A) computed tomography (CT)
B) ultrasound
C) magnetic resonance imaging
D) all of the above

Question 6

Digital imaging could only be developed after advances were made in _____.

A) microprocessors
B) semiconductor memory
C) photostimulable phosphors
D) both A and B

Question 7

The dynamic range determines the degree of _____ in the image.

A) contrast resolution
B) spatial resolution
C) motion blur
D) all of the above

Question 8

The primary limitation of fanned beam radiography is _____.

A) reduced spatial resolution
B) long scanning time
C) low contrast resolution
D) shortened dynamic range

Question 9

Computed radiography developed in the 1970s with the use of _____ as the image receptor.

A) phosphor
B) selenium
C) silicon
D) film

Question 10

In scanned beam radiography,the spatial resolution is determined by the _____.

A) number of detectors
B) width of the beam
C) semiconductor material
D) translation speed

Question 11

In digital radiography,spatial resolution is improved with increased _____.

A) field of view
B) Hounsfield units
C) pixel size
D) matrix size

Question 12

Digital radiography first began to be used in clinical settings in the _____.

A) 1960s
B) 1970s
C) 1980s
D) 1990s

Question 13

Computed radiography uses (a)_____ for latent image formation.

A) thin film transistors
B) photosensitive silicon chips
C) photostimulable phosphor
D) semiconductor material

Question 14

What is the most recent development in digital radiography image receptors?

A) fanned x-ray beams
B) linear array radiation detectors
C) photostimulable phosphors
D) direct capture solid-state devices

Question 15

Scanned projection radiography was developed as a complement to _____.

A) plain film radiography
B) computerized tomography
C) magnetic resonance imaging
D) nuclear medicine

Question 16

Scanned projection radiography differs from conventional radiography in the lack of _____.

A) patient motion
B) spatial resolution
C) contrast resolution
D) scattered x-rays

Question 17

Conventional x-ray tubes and cassettes are used with _____ radiography systems.

A) computed
B) scanned projection
C) direct capture
D) all of the above