Deck 28: Recorded Detail

Question 1

The best method for controlling motion when the patient is unable to cooperate is to

A)increase kVp.
B)maintain mAs, while decreasing time.
C)maintain mAs, while decreasing mA.
D)decrease kVp.

Answer 1

maintain mAs, while decreasing time.

Question 2

Recorded detail is

A)the degree of geometric sharpness.
B)definition.
C)the accuracy of the structural lines actually recorded in the radiographic image.
D)all of the above

Answer 2

all of the above

Question 3

Which radiograph exhibits the best detail?

A)a PA chest radiograph for evaluation of the heart at 40 in.
B)a PA chest radiograph for evaluation of the heart at 72 in.
C)an AP chest radiograph for evaluation of the heart at 40 in.
D)an AP chest radiograph for evaluation of the heart at 72 in.

Answer 3

a PA chest radiograph for evaluation of the heart at 72 in.

Question 4

The ____ represents a depth to the information in the digital image.

A)z axis
B)y-x grid matrix
C)y axis
D)x-y grid matrix

Question 5

Which can negatively impact recorded detail?

A)using small focal spot
B)good film-screen contact
C)involuntary motion
D)minimal OID

Question 6

As a last resort, which human immobilizer is used to hold a patient in position?

A)the radiography student
B)the radiologic technologist
C)the ER nurse
D)the male relative

Question 7

Resolution with intensifying screens will increase as ____ increases.

A)phosphor size
B)phosphor layer thickness
C)phosphor concentration
D)all of the above

Question 8

Spatial resolution in digital imaging is determined by the

A)bit depth.
B)matrix size.
C)pixel size.
D)all of the above

Question 9

Resolution is improved when

A)OID increases.
B)OID decreases.
C)SID decreases.
D)the x-ray tube is angled

Question 10

Slow film-screen combinations

A)increase resolution.
B)decrease radiographic density.
C)decrease patient dose.
D)require the small focal spot.

Question 11

Which measures the accuracy of an image compared to the original object on a scale of 0 to 1?

A)line spread function
B)modulation transfer function
C)point spread function
D)noise reduction function

Question 12

When evaluating the degree of resolution on an actual radiograhic image, an effective tissue to analyze is

A)heart size.
B)bony trabecular pattern.
C)kidney.
D)patient body fat stripes.

Question 13

Penumbra decreases as

A)focal spot decreases.
B)OID decreases.
C)SID increases.
D)all of the above

Question 14

The unit of resolution in film/screen imaging is

A)the Curie.
B)line pairs per millimeter.
C)pixel size.
D)the DEL size.

Question 15

Resolution is improved when

A)OID increases.
B)SID increases.
C)SID decreases.
D)the receptor is angled.

Question 16

A pixel bit depth of 2¹⁶ will demonstrate _______ shades of gray

A)16
B)32
C)65,536
D)none of the above

Question 17

All of the following affect visibility of detail EXCEPT

A)15% rule.
B)filtration.
C)radiographic grids.
D)SID.

Question 18

Poor resolution is caused by unacceptable levels of

A)density.
B)umbra.
C)penumbra.
D)contrast.

Question 19

As focal spot size decreases,

A)umbra is improved.
B)penumbra decreases.
C)resolution increases.
D)all of the above

Question 20

Factors affecting recorded detail include

A)kVp.
B)radiographic grids.
C)mAs.
D)focal spot size.

Question 21

When the sampling frequency is less than the Nyquist value,

A)aliasing is eliminated.
B)the Moire effect can occur.
C)patient dose must increase.
D)the Nyquist value must be altered.

Question 22

Calculate the penumbra for an image taken with a 1.0 mm focal spot, at a 40 in.distance, and OID of 2 in.

Question 23

You have completed a chest radiograph on a 2-month-old infant using a restraining device at a 72" SID.Because of the design of the device, your OID is suboptimum.The image reveals good resolution of the bony anatomy but the pulmonary vasculature is blurred.The EI value is 2040.In an effort to improve the quality of the repeat image, the competent radiographer would

A)raise the mA and decrease the exposure time.
B)decrease the SID and maintain the same mAs.
C)switch to small focal spot.
D)ask for mild sedation of the infant to decease respiration.

Question 24

Match the following choices with respect to recorded detail.
switching from 10:1 grid to 6:1 grid

A)PSF
B)quantum noise
C)resolution increase
D)MTF
E)MF
F)LSF
G)aliasing
H)loss of visibility of detail

Question 25

Imaging noise is different from quantum noise in that imaging noise

A)is a function of mAs.
B)is dependent upon kVp.
C)is inherent in the imaging system.
D)cannot be filtered out.

Question 26

Match the following choices with respect to recorded detail.
quantification of an imaging system's fidelity

A)PSF
B)quantum noise
C)resolution increase
D)MTF
E)MF
F)LSF
G)aliasing
H)loss of visibility of detail

Question 27

Calculate the penumbra for an image taken with a 1.0 mm focal spot, at a 40 in.distance and OID of 5 in.

Question 28

Match the following choices with respect to recorded detail.
switching from a RS 400 receptor to a RS 200 receptor

A)PSF
B)quantum noise
C)resolution increase
D)MTF
E)MF
F)LSF
G)aliasing
H)loss of visibility of detail

Question 29

As the spatial frequency of objects increases,

A)MTF increases proportionally.
B)MTF decreases.
C)MTF increases.
D)MTF computes to a value of 1.

Question 30

Calculate the penumbra for an image taken with a 2.0 mm focal spot, at a 40 in.distance, and OID of 2 in.

Question 31

In general radiography, quantum noise is

A)filtered out of images.
B)a function of mAs and kVp.
C)designed into the receptor specifications.
D)a recorded detail parameter.

Question 32

Calculate the penumbra for an image taken with a 2.0 mm focal spot, at a 72 in.distance, and OID of 1 in.

Question 33

For general radiography, an MTF value of 1 is

A)average.
B)suboptimum.
C)theoretically impossible.
D)a function of mAs.

Question 34

Match the following choices with respect to recorded detail.
results from insufficient mAs

A)PSF
B)quantum noise
C)resolution increase
D)MTF
E)MF
F)LSF
G)aliasing
H)loss of visibility of detail

Question 35

Match the following choices with respect to recorded detail.
the quotient of SID over SOD

A)PSF
B)quantum noise
C)resolution increase
D)MTF
E)MF
F)LSF
G)aliasing
H)loss of visibility of detail

Question 36

The Nyquist frequency is

A)important in analog imaging.
B)sampling a minimum of twice per cycle.
C)unique to radiography.
D)related to involuntary motion.

Question 37

The overall general shape of human anatomical structures are

A)round or oval.
B)linear.
C)cuboid.
D)curvilinear.

Question 38

In digital imaging systems , increasing sampling frequency of the data

A)increases dose.
B)increases image fidelity.
C)decreases MTF.
D)decreases dose.

Question 39

Match the following choices with respect to recorded detail.
creates a Moire effect

A)PSF
B)quantum noise
C)resolution increase
D)MTF
E)MF
F)LSF
G)aliasing
H)loss of visibility of detail

Question 40

A digital detector with a high fill factor

A)will produce poor resolution.
B)will require longer processing time.
C)will produce high resolution.
D)is undesirable.

Question 41

Calculate the SID necessary to achieve a penumbra of 0.8 mm if the focal spot size is 1.0 mm and the object is 3 inches from the detector.

Question 42

Calculate the penumbra for an image taken with a 2.0 mm focal spot, at a 72 in.distance, and OID of 6 in.