Arrt Section 3: Image Acquisition & Evaluation, Criteria For Image Evaluation

Front 1

Digital receptor exposure is __________ to the selected mAs.

Back 1

Directly proportional

Front 2

Digital receptor exposure is __________ the selected SID.

Back 2

Inversely proportional to the square of

Front 3

In CR, what is used to express an acceptable exposure level to the PSP?

Back 3

The recommended exposure range is dependent on equipment type

S#

EI Value

lgM#

Front 4

What is the term used to describe the numeric value representative of the exposure the IR receives in digital radiography?

Back 4

Exposure indicator (EI)

Front 5

What should the radiographer use as a guide to evaluate a CR image and determine if it has been optimally exposed?

Back 5

The exposure indicator should indicate values within the recommended range

Front 6

From this list of factors, select the ones that have an effect on digital image contrast/grayscale: pixel bit depth, window width, window level, matrix size, pixel density, LUT.

Back 6

Pixel bit depth

Window width

LUT

Front 7

From this list of factors, select the ones that have an effect on digital image brightness: pixel bit depth, window width, window level, matrix size, pixel density.

Back 7

Window level

Front 8

From this list of factors, select the ones that have an effect on digital image resolution: pixel density, window level, pixel pitch, matrix size, window width.

Back 8

Pixel density

Pixel pitch

Matrix size

Front 9

What is the exposure indicator in DR systems?

Back 9

DAP (dose-area product)

Front 10

Where is the location of the DAP meter used in DR?

Back 10

At the collimator

Front 11

What are the two types of distortion?

Back 11

Size and shape

Front 12

What influences shape distortion?

Back 12

Tube, part, and IR alignment

Front 13

What influences size distortion?

Back 13

OID and SID

Front 14

What kind of patient information can be made part of the recorded image?

Back 14

Patient name/MRN

Date

Institution

Side marker

Patient position

Time of study

Front 15

Select the conditions that are likely to require an increase in exposure: acites, multiple myeloma, pleural effusion, congestive heart failure.

Back 15

Acites

Pleural effusion

Congestive heart failure

Front 16

Select the conditions that are likely to require a decrease in exposure: emphysema, bowel obstruction, hydrocephalus, edema.

Back 16

Bowel obstruction

Emphysema

Front 17

What change in exposure is required when using iodine or barium contrast agents?

Back 17

Increase

Front 18

What causes an aliasing artifact in digital imaging?

Back 18

If a grid used in CR has a frequency similar to the CR processor's scan frequency

Front 19

When might background radiation artifacts occur in CR Imaging?

Back 19

When using an IP that has not been used or erased for 48 hours or more

Front 20

The aliasing artifact, occasionally seen in digital imaging, is sometimes called __________.

Back 20

Moiré effect

Front 21

What does the abbreviation MTF represent?

Back 21

Modulation transfer function

Front 22

What is the best way to express digital detector image resolution?

Back 22

MTF

Front 23

What does mAs control/regulate in digital imaging?

Back 23

Patient dose

Receptor exposure

Quantity of image-forming radiation

Front 24

How will the resulting image appear if there are too few x-ray photons reaching the digital image receptor?

Back 24

Quantum mottle

Front 25

What do exposure indicators indicate in digital imaging?

Back 25

The acceptable range of exposure

Front 26

Digital Imaging systems are __________ sensitive to scattered radiation than film emulsion.

Back 26

More

Hint 26

More or less

Front 27

__________ collimation should always be used with digital systems because excessive scatter causes __________ errors.

Back 27

Close

Histogram analysis