Digital Radiography Final Review

Front 1

Film and intensifying screens are primarily in ____________.

Back 1

conventional radiography

Front 2

Which modality was the first to use the principle of digital imaging?

Back 2

CT

Front 3

Who was the first to incorporate digital imaging with the CT scanner?

Back 3

Godfrey Hounsfield

Front 4

True or False: The earliest computed tomography of the head took several hours to acquire a single slice of information.

Back 4

True

Front 5

Early reconstruction of raw computed tomography data tool a few ____________ to form a recognizable image.

Back 5

days

Front 6

The first commercial CT scanners could image the ____________.

Back 6

head only

Front 7

Teleradiography incorporated _________ to produce radiographic images.

Back 7

telephone lines

Front 8

One of the early goals related to the development of PACS was to ____________.

Back 8

provide a means to move battlefield images to an established hospital

Front 9

True or False: When switching from a conventional diagnostic radiography room to one that incorporates computed radiography, major equipment changes are to be expected.

Back 9

False

Front 10

A server is ________.

Back 10

a computer that manages resources for other computers

Front 11

The first version of DICOM was completed in ________.

Back 11

1985

Front 12

The standard that oversees most computerized clinical and administrative data is known as ________.

Back 12

HL-7

Front 13

RIS is specific to _________.

Back 13

radiology

Front 14

The system that holds a specific patient's lab results, radiology reports, and physician notes is the _______.

Back 14

HIS

Front 15

The workstation function that allows selection of preset terms and/or manual text input is termed ____________.

Back 15

annotation

Front 16

Input of annotation for identification of the patient's left or right side ___________.

Back 16

should only be used in conjunction with the technologist's markers

Front 17

Magnification of the entire image at the workstation is termed __________.

Back 17

zoom

Front 18

Proper patient demographic input ensures _________.

Back 18

linking of all the patient's files

Front 19

Proper patient demographic input is the responsibility of the ____________.

Back 19

technologist

Front 20

The acronym PACS stands for ____________ system.

Back 20

Picture Archival and Communication

Front 21

A universally accepted standard for exchanging medical imaging via a networked set of display workstations, archive, and imaging modalities is ______________.

Back 21

DICOM

Front 22

Reading images on a computer screen is known as _________ reporting.

Back 22

soft copy

Front 23

Any computer that a health care worker uses to view a digital image is a _____________.

Back 23

display workstation

Front 24

Which part of the PACS houses all of the historic digital image data along with the current digital data being generated by the modalities?

Back 24

archive

Front 25

The acronym RIS stands for _____________ system.

Back 25

Radiology Information

Front 26

What term is used to describe the reading of images outside of the hospital walls, generally at home or in remote locations?

Back 26

teleradiology

Front 27

Which is the most interactive part of a PACS?

Back 27

display workstation

Front 28

Which term best describes a basic picture element on a display?

Back 28

pixel

Front 29

If a number of ________ increases on a monitor, resolution ___________.

Back 29

pixels; improves

Front 30

Which of the following would be considered categories for display workstations?

1) primary reading

2) technologist QC

3) archive server

Back 30

1 and 2

Front 31

Which workstation is used to review images after acquisition but before being sent off for reporting?

Back 31

technologist review station

Front 32

Which of the following would be considered categories of workstation functions?

1) navigation

2) image manipulation and enhancement

3) image management

Back 32

1, 2, and 3

Front 33

Which set of functions is used to move through images, series, studies, and patients?

Back 33

navigation functions

Front 34

Which function determines how images are displayed on the monitor(s)?

Back 34

hanging protocol

Front 35

Which function allows the user to move through a series of images frame by frame?

Back 35

cine

Front 36

Which function can be used to orient the image in the anatomic hanging position?

Back 36

flip/rotate

Front 37

Which function increases the size of an area on the image?

Back 37

pan/zoom

Front 38

Which advanced function allows the user to put multiple images together into one single image, such as scoliosis series?

Back 38

stitching

Front 39

The place where records or documents are preserved for historic purposes is the ________.

Back 39

archive

Front 40

Which information might be found in the DICOM header of an image?

Back 40

patient name and ordering physician

Front 41

The CR cassette is backed by aluminum that __________.

Back 41

absorbs x-rays

Front 42

What part of the cassette serves to protect against static buildup, dust collection, and mechanical damage to the imaging plate?

Back 42

felt material

Front 43

The imaging layer that absorbs stimulating light and reflects emitted light is the ________ layer.

Back 43

color

Front 44

The reflective layer ___________.

Back 44

sends light in a forward direction

Front 45

The purpose of the barcode label is to identify the ___________.

Back 45

imaging plate

Front 46

The phosphor layer is made of phosphors from the ___________ family.

Back 46

barium fluorohalide

Front 47

The signal trapped in the phosphor center is _________.

Back 47

never completely lost

Front 48

During the laser beam formation, both ends of the laser reflect energy back and forth so that the atoms __________.

Back 48

bombard each other

Front 49

Coherent light is formed by the laser because the photons ___________.

Back 49

travel in the same direction

Front 50

The power source for the laser must be ________.

Back 50

constant

Front 51

The wavelength of the CR reader laser is ________ nm.

Back 51

633

Front 52

The laser scans the imaging plate in a __________ pattern.

Back 52

raster

Front 53

CR imaging plates are erased by flooding the plate with _______.

Back 53

light

Front 54

The amount of detail present in any image is known as ___________.

Back 54

spatial resolution

Front 55

Selection of the incorrect body part from the examination menu may result in ___________.

Back 55

image misinterpretation

Front 56

The range of kVp that can be used with CR is _______.

Back 56

45 to 120 kVp

Front 57

When insufficient light is produced by the imaging plate phosphor, the image will __________.

Back 57

be grainy

Front 58

Quantum mottle is caused by ___________.

Back 58

insufficient light

Front 59

What should be considered when selecting the CR cassette?

Back 59

size and type

Front 60

Using an imaging plate that is much larger than the part being examined will ___________.

Back 60

decrease resolution

Front 61

The higher the number of pixels in a matrix, the ____________.

Back 61

higher the image resolution

Front 62

The moire artifact results when grid lines and scanning laser are _________.

Back 62

parallel

Front 63

The number of grid lines per centimeter or lines per inch describes _________.

Back 63

grid frequency

Front 64

Grid ratio describes the _________.

Back 64

relationship between the height of the lead strips to the interspace

Front 65

Collimation to a smaller area _________ Compton interactions.

Back 65

decreases

Front 66

Shuttering, a post-exposure image manipulation technique, is _________.

Back 66

added to the screen image

Front 67

A technologist can lend credibility to his or her expertise by ________.

Back 67

using personal position markers

Front 68

The exposure indicator number is an _______.

Back 68

indication of radiation absorbed by the imaging plate

Front 69

In all systems, exposures outside the range indicate ___________.

Back 69

both overexposure and underexposure

Front 70

A histogram is ____________.

Back 70

a graphic representation of x-ray exposure

Front 71

What device in the reader detects the light being released from the PSP plate during reading?

Back 71

photodetector

Front 72

When is the PSP plate erased?

Back 72

after every PSP plate is read; by flooding it with bright light; and manually by selecting the proper eraser method

Front 73

True or False: Too much mAs will cause quantum mottle.

Back 73

False

Front 74

True or False: If grid lines are present and run parallel to the scanning laser, the image will not have the moire pattern present.

Back 74

False

Front 75

True or False: Overexposure will reduce the contrast resolution of the image.

Back 75

True

Front 76

uses amorphous selenium, x-rays are converted directly into electrons (only Hologic)

Back 76

direct TFT arrays

Front 77

uses a scintillator, which converts x-rays to light, and then light is converted into electrons by a silicon layer just above the TFT (all other vendors)

Back 77

indirect TFT arrays

Front 78

Structured phosphor layers demonstrate _________ than turbid phosphor.

Back 78

less light spread

Front 79

uses a scintillator; these systems are camera-like (uses lenses to focus the light onto a detector)

Back 79

CCD and CMOS

Front 80

predicts how high or low the patient dose may be

Back 80

DQE

Front 81

means you may have lower patient doses

Back 81

higher DQE

Front 82

What is the result if DQE is too high?

Back 82

the image will be noisy due to low mAs

Front 83

factors that influence the DQE

Back 83

phosphor absorption efficiency and conversion efficiency

Front 84

refers to the operational exposure level at which a digital system is operated

Back 84

speed class

Front 85

As speed class increases, ______________.

Back 85

the likelihood of noise increases

Front 86

As speed class decreases, __________.

Back 86

the patient exposure increases

Front 87

amount of error for optimal image acquisition

Back 87

latitude

Front 88

provides a false sense of very large latitude

Back 88

automatic rescaling

Front 89

What is the result if there is a significant difference between image data set histogram and the model?

Back 89

a histogram analysis error may occur resulting in a poor quality image displayed

Front 90

DAP

Back 90

dose area product

Front 91

How is actual patient dose measured?

Back 91

by a DAP meter embedded in the collimator

Front 92

How often must readers be recalibrated for exposure indicators to be meaningful?

Back 92

annually, with a calibrated ion chamber by a medical physicist or qualified service engineer

Front 93

In regards to centering and beam collimation, what may cause a histogram analysis error and lead to incorrect exposure indicators?

Back 93

misalignment

Front 94

In order to limit patient dose, ________ should be used to compensate for grid use rather than ______.

Back 94

kVp; mAs

Front 95

a software function to reduce the appearance of noise in your image

Back 95

smoothing

Front 96

an artificial increase in display contrast at an edge

Back 96

edge enhancement

Front 97

a software function designed to even the brightness displayed in the image

Back 97

equalization

Front 98

degrades visibility of specific anatomical structures; may cause false information resulting in missed or misdiagnosis due to inappropriate default processing

Back 98

effects of excessive processing

Front 99

True or False: Digital is exposure driven.

Back 99

True - the digital detector is unable to discriminate whether exposure change was mAs or kVp; what matters is exposure to pixels

Front 100

Inappropropriate collimation will cause ________.

Back 100

a histogram analysis error

Front 101

A grid should be used when the remnant beam is more than _________.

Back 101

50% scatter, chest larger than 24cm and anything else larger than 12cm

Front 102

Geometric rules of ___________ and _________ are unchanged from film to digital.

Back 102

recorded detail; distortion

Front 103

Digital systems are more sensitive to ________ and ______________.

Back 103

scatter; background radiation

Front 104

Use of ___________ of copper is recommended to reduce patient dose.

Back 104

0.1 to 0.2 mm

Front 105

How often should cleaning and inspecting plates be done?

Back 105

every 3 months or as needed due to conditions

Front 106

How often should plates be erased if unused?

Back 106

every 48 hours

Front 107

All systems within a facility should use ______________ to ensure image appearance consistency.

Back 107

identical processing codes

Front 108

Film is very sensitive to ______ both before and after printing.

Back 108

heat

Front 109

DR can further be divided into two categories:

Back 109

direct and indirect

Front 110

absorb x-rays and convert them into light; the light is detected by an area CCD or TFT array and then converted into an electrical signal that is sent to the computer for processing and viewing

Back 110

indirect capture DR devices

Front 111

convert the incident x-ray energy directly into an electrical signal; uses a photoconductor as the x-ray absorber, and sends the signal to the computer for processing and viewing

Back 111

direct capture devices

Front 112

Film/screen exposure latitude is based on the characteristic response of the film, which is ___________.

Back 112

nonlinear

Front 113

CR/DR uses a detector that can respond in a ___________ manner only.

Back 113

linear

Front 114

LUT

Back 114

look up table

Front 115

a table that maps the image grayscale values into some visible output intensity on a monitor or film

Back 115

LUT

Front 116

mAs influences ________________

Back 116

image noise

Front 117

Density is controlled by ______________.

Back 117

algorithms

Front 118

thin, tough, clear plastic that protects the phosphor layer

Back 118

protective layer

Front 119

layer of phosphors that "traps" electrons during exposure; contains a dye that absorbs the light to prevent spread

Back 119

phosphor (active) layer

Front 120

absorbs and reduces static electricity

Back 120

conductive layer

Front 121

absorbs the stimulating light but reflects emitted light

Back 121

color layer

Front 122

semi-rigid material that gives the imaging sheet some strength

Back 122

support layer

Front 123

soft polymer layer that protects the back of the cassette

Back 123

backing layer

Front 124

Trapped signal will remain for __________, but the deterioration begins ______________.

Back 124

hours, even days; almost immediately

Front 125

LASER

Back 125

light amplification of stimulated emission of radiation

Front 126

The wavelength is ________ nm for helium laser.

Back 126

633

Front 127

The wavelength is _________ nm for solid state.

Back 127

670 to 690

Front 128

The trapped electrons escape the active layer where they emit visible _____________.

Back 128

blue light