Deck 10: Concepts of Radiographic Image Quality

Question 1

Spatial resolution improves with decreased _____ blur.

A) screen
B) motion
C) geometric
D) all of the above

Answer 1

all of the above

Question 2

A film with a characteristic curve showing a high slope would be useful when _____ is needed.

A) low contrast
B) wide latitude
C) high contrast
D) fine detail

Answer 2

high contrast

Question 3

Subject contrast is affected by _____.

A) mAs
B) focal spot size
C) patient thickness
D) voltage ripple

Answer 3

patient thickness

Question 4

A high quality radiograph should always demonstrate _____.

A) structures and tissues
B) high contrast
C) minimum magnification
D) all of the above

Question 5

The base + fog of a film is shown below the _____ of the characteristic curve.

A) straight-line portion
B) average gradient
C) toe portion
D) shoulder portion

Question 6

_____ is defined as the ability to image two separate objects and visually detect one from the other.

A) Contrast
B) Resolution
C) Detail
D) Noise

Question 7

In general radiography,the useful optical densities lie between _____ and _____.

A) 0.25, 2.25
B) 0.5, 1.0
C) 1.0, 1.5
D) 2.0, 3.0

Question 8

The best way to minimize magnification is to use a _____.

A) long SID
B) small OID
C) large OID
D) both A and B

Question 9

If 10% of the viewbox light is transmitted through an area of film,what is the optical density in that area?

A) 0
B) 1
C) 2
D) 3

Question 10

The three primary geometric factors affecting image quality are _____.

A) distortion, subject contrast, and mAs
B) patient thickness, distortion, and magnification
C) magnification, distortion, and focal spot blur
D) kVp, focal spot blur, and contrast

Question 11

Distortion can be reduced by _____.

A) placing the object plane perpendicular to the image plane
B) placing the object plane parallel to the image plane
C) directing the central ray 15° from the object plane
D) increasing the SID and the OID

Question 12

The slope of the _____ portion of the characteristic curve shows the film contrast.

A) base
B) shoulder
C) toe
D) straight line

Question 13

The inherent base density plus fog density in film is _____.

A) 0.0-0.1
B) 0.1-0.3
C) 0.5-1.0
D) 1.0-1.3

Question 14

An image receptor with _____ can be used over a greater range of exposures.

A) wide latitude
B) high contrast
C) narrow latitude
D) high average gradient

Question 15

What is the formula for optical density?

A) OD = log10(Io/It)
B) OD = log10(It/Io)
C) OD = Io/It
D) OD = It/ Io

Question 16

Higher speed image receptors generally produce images with _____.

A) better resolution
B) increased noise
C) higher contrast
D) improved detail

Question 17

Radiographic _____ is random fluctuation in the optical density of a radiograph.

A) detail
B) contrast
C) noise
D) resolution

Question 18

The densities above 2.5 on a film are represented in the _____ portion of the characteristic curve.

A) base + fog
B) toe
C) straight-line portion
D) shoulder

Question 19

What is the formula for the magnification factor?

A) MF = SID/SOD
B) MF = SOD/SID
C) MF = (SID/SOD)2
D) MF = SID2/SOD

Question 20

Focal spot blur can be reduced by using _____.

A) a small focal spot
B) a shorter SID
C) a larger OID
D) all of the above

Question 21

Radiographic image quality is improved when the _____ is increased.

A) source image distance
B) focal spot size
C) film speed
D) screen speed

Question 22

Which of these body parts has the highest subject contrast?

A) abdomen
B) skull
C) chest
D) pelvis

Question 23

The technologist primarily controls radiographic contrast by varying the _____.

A) image receptor
B) kilovoltage
C) voltage ripple
D) milliamperage

Question 24

Patient thickness affects image quality by affecting _____.

A) magnification
B) radiographic contrast
C) focal spot blur
D) all of the above

Question 25

Optical density is primarily controlled by changing the _____.

A) kVp
B) mAs
C) film
D) SID