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test questions > Unit tests for final review 2233 > Flashcards

Unit tests for final review 2233 Flashcards

1
Q

Intensifying screens

A

emit light

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2
Q

What was the first modality to use the process of digital imaging in diagnostic radiology

A

CT

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3
Q

Digital radiography was first introduced by

A

fuji in 1983

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4
Q

The computer radiography cassette is called what?

A

Imaging plate

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5
Q

Computed radiography and the screen-film imaging both have what?

A

latent image

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6
Q

When switching from screen film imaging to computed radiography, which step in the processing is elimitated for the technologist

A

Reloading the cassettes

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7
Q

An a digital radiography system, which of the following are needed to produce a radiographic image?

A

X-ray absorber and CCD

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8
Q

What is used in PSP image capture to release the latent image
What is used in PSP image capture to release the latent image

A

Focused laser light

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9
Q

T or F? changing matrix or the FOV will not change the size of the pixel.

A

F! You can change the matrix without affecting the FOV and you can change the FOV without affecting the matrix, but a change in either one will change the pixel size

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10
Q

Each square in a matrix is called

A

A picture element or pixel

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11
Q

The measurement for radiation that was incident on the image receptor for a particular exposure is known as

A

K IND

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12
Q

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

A

Godfrey Hounsfield

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13
Q

Early picture archival and communication systems were developed

A

By the U. s military

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14
Q

Teleradiography utilized what to produce radiographic images?

A

Telephone lines

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15
Q

Compared with a 90 second processing time found in conventional radiography, image acquisition with digital radiography has now been reduced to

A

3 -5 seconds

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16
Q

In conventional radiography film processing the sensitivity speck has this electrical charge

A

Negative

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17
Q

Another name for exposure latitude is

A

Dynamic range

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18
Q

What controls optical density in conventional radiography

A

mAs

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19
Q

The perfect image and Processing System would have A MTF of

A

100 percent

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20
Q

The ____ is a measurement of the percentage of x-rays that is absorbed when they hit the detector

A

DQE

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21
Q

Which of the following cannot be controlled by the technologist and is much dependent on manufacturer and detector quality

A

Equipment noise

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22
Q

The nyquist theorem says that the

A

Sampling frequency must be twice the input signal bandwidth

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23
Q

Changing the slope of the look-up table graph will increase or decrease the

A

Contrast

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24
Q

The first version of DICOM was completed in

A

1985

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25
Q

Low pass filtering is also called

A

Smoothing

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26
Q

An image manipulation process that fills in the background so that it is darkened is also known as

A

shuttering

Shuttering

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27
Q

Annotating for the purpose of identifying the patient’s left or right side

A

Should be used in conjunction with the technologist’s markers

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28
Q

T or F ? Computed radiography in digital radiography can use the existing diagnostic equipment found in today’s imaging room

A

False

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29
Q

DICOM is a standard that allows imaging modalities and PACS to commnuicate in the same language. True or false?

A

True

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30
Q

Data collected within the collimator are represented by A

A

Pixel graph histogram

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31
Q

What to intensifying screens to do

A

Emits light

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32
Q

Teleradiology, moving images of via the telephone line was concepturalized by

A

Albert jutras

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33
Q

The x-ray absorber typically used in direct capture is a

A

Photo conductor

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34
Q

The first full-scale PACS was installed in 1993 in

A

Baltimore

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35
Q

True or false? A Bucky apparatus is required for digital radiography

A

False

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36
Q

Is sample resolution a critical characteristics of a digital image ?

A

no

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37
Q

The number of bits per pixel is called its

A

Pixel depth

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38
Q

Which of the following terms determines the size of the pixel

A

Matrix

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39
Q

How dark or how light a digital image appears on a monitor is called

A

Brightness

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40
Q

If the entire range of exposures were digitized, pixel values representing what would be digitized

A

All the values

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41
Q

They range of exposure values the image detector is able to produce is known as

A

latitude

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42
Q

The histogram displays the useful signal by locating

A

Maximum and minimum signals

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43
Q

High pass filtering is useful for enhancing

A

Organs and soft tissue

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44
Q

What is the amplification of the frequencies in the areas of interest

A

Edge enhancement

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45
Q

Window____ controls contrast, whereas window ___ blank controls ratio of black and white

A

width ; width

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46
Q

What part of the body was the first area scanned by a CT scanner

A

head

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47
Q

S, IgM, and EXI are symbols for

A

Exposure indicator or vendor specific exposure indicators

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48
Q

The acronym DICOM stands for

A

Digital imaging and communications in medicine

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49
Q

The computed radiography cassette is backed by aluminum that

A

Absorbs x-rays

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50
Q

Which one of the following serves to protect against static buildup, dust collection, and mechanical damage to the imaging plate

A

felt material

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51
Q

The reflective layer

A

Sends light in a forward direction

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52
Q

When the imaging plate is irradiated, stimulated electrons enter the

A

Active layer

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53
Q

The optical mirror in the reader

A

Directs the laser beam to the imaging plate surface

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54
Q

The devices that moves the laser rapidly back and forth across the imaging plate is known as

A

beam deflector

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55
Q

The power source for the laser must be

A

Constant

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56
Q

Imaging plates should be erased every

A

week

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57
Q

Computed radiography imaging plates are erased by flooding the plate with

A

Light

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58
Q

The number of bits per pixel is known as bit

A

Depth

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59
Q

The amount of detail present in any image is known as

A

Spatial resolution

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60
Q

The imaging plate reader uses a laser to scan the imaging plate, releasing the energy stored in the phosphor layer as

A

Blue light

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61
Q

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

A

Image misinterpretation

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62
Q

Kilovoltage Peak can be chosen

A

For the type and amount of contrast desired

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63
Q

The range of Kilovoltage Peak that can be used for computed radiography is

A

45 to 120 Kilovoltage Peak

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64
Q

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

A

be grainy

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65
Q

Which of the following should be considered when selecting this CR cassette

A

Size and type

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66
Q

The higher the number of pixels in a matrix and the

A

Higher the image resolution

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67
Q

Grid use for CR examinations is more critical than in film screen radiography because CR

A

Imaging plates record more densities

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68
Q

Grid ratio describes the

A

Relationship between the height of the lead strips to the interspace

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69
Q

Which of the following require more critical beam centering

A

Focused grid

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70
Q

Collimation to a smaller area

A

Decreases Compton interaction

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71
Q

A device that includes a photosensitive array and small pixels that convert light into electrical charges is known as a

A

Thin film

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72
Q

Flat camel detectors that use indirect conversion technology convert

A

X-ray is to visible light

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73
Q

The type of flat-panel detector that uses thin films of silicon integrated with a raise of photodiodes is known as a

A

Amorphous silicon detector

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74
Q

cesium iodide detectors use

A

Thin crystalline needles

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75
Q

A highly efficient indirect conversion system that takes up less fill space than CCD is known as

A

CMOS

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76
Q

When specialized pixels in a complementary metal oxide silicon system are struck with x-ray photons

A

All of the above

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77
Q

Digital imaging systems have

A

Wider DQE latitude than screen film systems

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78
Q

The DQE of detectors changes with changes in

A

KVp

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79
Q

The main factor that limits image quality in cassetteless image acquisition is

A

noise

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80
Q

Data collected within the collimator are represented by a

A

Histogram

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81
Q

The higher than kVp the

A

Narrower the histogram

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82
Q

The longer an image is stored in the CR cassette the

A

More energy is lost by the electrons

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83
Q

The wraparound image or image aliasing occurs when

A

Sampling occurs less than twice per cycle

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84
Q

The phosphor layer is made of phosphors from the

A

Barium fluorohalide family

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85
Q

Typical cassette throughput is

A

50 cassettes per hour

86
Q

The difference between CCD and CMOS is

A

CCD Systems have a higher light sensitivity than CMOS

87
Q

Materials that absorb x-rays and produce electrical charges are called

A

Photo conductors

88
Q

The device that acts like a switch to send electrical charges to the image processor in a direct conversion flat-panel detector is called a

A

Field effect

89
Q

Amplifiers perform all of the following functions except

A

Noise canceling

90
Q

True or false? Amorphous selenium is a scintillator

A

False

91
Q

According to bushong what percent of excited electrons return to their Normal State before digital reading

A

50 percent

92
Q

Which of the following detectors uses crystalline needles

A

cesium iodide

93
Q

The movement of the cassette through the reader is termed

A

Slow scan

94
Q

The term turbid refers to

A

A and C

95
Q

The components that focus the signal from the scintillators to the charge-couple device are called

A

Fiberoptics

96
Q

When statement best describes a capacitor

A

It converts x-ray photons to light and stores it

97
Q

Detector elements are formed by voltage gates that ___ at readout to ____ the flow of electrons

A

Are open and close; allow

98
Q

In PACs consist of the following

A

1 storage device 2 display WorkStation 3 imaging modality

99
Q

What is the universally accepted standard for exchanging medical imaging via a network. It allows the components to talk to each other.

A

DICOM

100
Q

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

A

Archive

101
Q

What term is used to describe a database that is running two identical databases simultaneously

A

Mirrored

102
Q

Which of the following are true as it relates to the imaging manager

A

It contains the master database of all on the archive and in controls the receipt of all images

103
Q

Which device scans an analog film and produces numeric signals based on the appearance of the film

A

Film digitizer

104
Q

And Blanc is any supplemental device connected to a PACs that performs a specific function

A

Peripheral

105
Q

The ultimate focus in Health Care is to improve___and provide___so that patients will want to return

A

Patient care; high-quality service

106
Q

Most healthcare institutions are accredited by

A

Joint commission

107
Q

Any computer that a healthcare worker uses to view a digital image is a

A

Display WorkStation

108
Q

Which of the following are considered PACs architectures

A

1 distributed system
2 client server based system
3 web based system

109
Q

Which PACs component interfaces with the radiology information system and the hospital information system

A

Image manager

110
Q

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

A

Patient name and ordering position; Not lab results

111
Q

Which component of the archive consists of the physical Storage Devices

A

Image storage and archive server; not image manager

112
Q

The acronym for raid is

A

Redundant array of inexpensive disks or redundant array of independent disks

113
Q

Which of the following terms is used when data is broken up into pieces and each disk receives a piece of data

A

striping

114
Q

Which term is used to describe the process of transferring images to remote location for reading by a radiologist

A

Teleradiology

115
Q

When term describes the technology that allows a film to be digitized and then analyzed by a computer to alert the radiologist of possible questionable areas on a radiograph

A

CAD

116
Q

The binary code is a computer language based on___and___

A

Zero; one

117
Q

A film imager is also known as a film___

A

Printer

118
Q

Most QA activities produce___data

A

Quantitative

119
Q

Testing performed before newly installed or majorly-repaired equipment can be operated by the department is called___testing

A

Acceptance

120
Q

___is defined as a comprehensive set of activities designed to monitor and maintain systems that produce a product

A

Quality control

121
Q

Which system does the acquisition modalities send their images directly to a designated workstation?

A

distributed

122
Q

Which RAID level have all the data and error correction (parity) striped across all connected disks?

A

RAID 5

123
Q

Which of the following are commonly used as long term storage for DICOM imager?

A

Digital linear tape and optical disks

124
Q

What do dry imagers use to develop the image on the film?

A

heat

125
Q

Dry imager film is more sensitive to what in comparison to conventional film?

A

heat and humidity

126
Q

Errors in equipment performant are usually detected by poor

A

quality outcomes

127
Q

Continuous quality improvements tend to focus on____ rather than the ____

A

process/people

128
Q

QA/QC programs focus on ___ quality, whereas CQI focuses on ___ the process

A

maintaining/ improving

129
Q

The SMPTE focuses on ___ quality

A

monitor

130
Q

What factors might be used when determining the best type of monitor for each workstation?

A

Resolution, size, and monitor orientation

131
Q

The number of pixels contained on a display is known as…

A

resolution

132
Q

Which of the following is an archive storage configuration that has RAID arrays directly attached to the network?

A

NAS

133
Q

What is a term that describes the act of keeping a complete copy of the archive in another remote location?

A

disaster recovery

134
Q

What is most often the weakest link in the digital imaging chain?

A

monitor

135
Q

a device used to measure the luminescence of areas on the monitor is called a

A

photometer

136
Q

The luminescence of a monitor should be check on a ____ basis

A

daily

137
Q

Which workstation might be used to print copies of images or burn images to a CD for outside use?

A

image management workstation

138
Q

The ___ is used to move through images, series, studies, and patients.

A

navigation function

139
Q

Which function represents the range of gray values that are being viewed on the monitor?

A

window

140
Q

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

A

stitching

141
Q

Which RAID level is most often used in PACS archives?

A

RAID 5

142
Q

Another way to distribute digital images around the hospital is

A

Dry/wet laser images

143
Q

___ is the measurement of whether all images completed at the modality makes it to PACS?

A

Data integrity

144
Q

What is used to reduce the size of the image file to increase the speed of the network’s transfer of the images?

A

compression

145
Q

The CPU is

A

a microprocessor found on the motherboard

146
Q

How many bytes are used to store one alphanumeric character?

A

1

147
Q

The series of connections controllers, and chips that create the information highway within the computer system is known as the

A

bus

148
Q

RAM is

A

short term for open programs

149
Q

Which of the following is not a commonly used mouse?

A

laser

150
Q

UNIX was developed by

A

bell

151
Q

Which one of the following is not considered type of computer found on network?

A

peer to peer

152
Q

A handheld personal organizer of a ____ operating system.

A

single user; single task

153
Q

In which network type is each computer on the network considered equal/

A

peer to peer

154
Q

A network that uses a central computer that sends the entire original resource to the client is known as a ___.

A

server based network

155
Q

Which of the following describes a thick client computer

A

a computer that works independently of the network

156
Q

Most network interface cards plug directly into the

A

motherboard

157
Q

The network layers breaks up data and

A

decides which network path to take

158
Q

which of the following is not one of the 20 parts of the DICOM standard?

A

data thesaurus

159
Q

PACS stands for…

A

Picture Archiving and Communication System

160
Q

Someone who is trained on all aspects of PACS, prepared to educate others, and sets up ongoing training sessions…

A

superuser

161
Q

Who should do the annual and acceptance testing?

A

physicist

162
Q

companies that provide the outsourcing of archiving and management function for pay are called…

A

application server provider

163
Q

Each sweep of the source-detector around the body during CT is called a

A

translation

164
Q

CT is able to differentiate between tissues with similar densities compared with conventional due to …

A

improved contrast resolution

165
Q

4th generation CT scanners use which of the following?

A

only rotating tube

166
Q

An array of numbers arranged in a grid of rows and columns is called

A

a matrix

167
Q

The reference material for CT is ___ and is related to the ___ of the tissue

A

water; linear attenuation coefficient

168
Q

contrast is adjusted by windowing, changing the window width, and window level. Window determines the ____

A

midpoint of the gray range

169
Q

Factors that affect image quality in CT consist of

A

spatial resolution and noise…not contrast media

170
Q

oral contrast for CT should be mixed so it is….

A

less concentration than for general examinations

171
Q

The advantages of MSHCT are

A

multiphase studies, isotropic viewing, improved spatial resolution

172
Q

Radiation dose in CT is considered to be

A

size dependent

173
Q

Each CT projection is ____ as it is scanned

A

stored on the computer

174
Q

The cross section anatomy is translated into ___ during CT reconstruction.

A

Matrix of values

175
Q

The first generation of CT scanners used ___ detectors

A

one

176
Q

the principle advantage of the 2nd generation CT scanner was…

A

reduced scanning time

177
Q

3rd generation CT scanners further improved on

A

scanning time and scattered radiation

178
Q

Which of the following was the first CT scanner to have the fan beam transect the patient?

A

3rd

179
Q

Many CT x-ray tubes have the capacity for millions of ___with each exam

A

heat units

180
Q

CT scanners operate with ___ voltage generators

A

high frequency

181
Q

CT imaging has excellent ___ because of the narrow beam collimation

A

contrast resolution

182
Q

The pixel size is reduced when the ___ size is increased and the ___ size is fixed.

A

matrix; field of view

183
Q

The efficiency of spatial resolution in any CT imaging system is limited to the size of the

A

pixel

184
Q

image noise in CT scanning can depend on…

A

pixel size
detector efficiency
slice thickness

185
Q

The patient dose in CT is determined by the ____ collimator

A

prepatient

186
Q

For a facility to be ACR accredited, which of the following is true?

A

Must meet all equipment test standards and technologist must be CT certified NOT radiologist must be general trained

187
Q

Which CT scanner is best suited for doing cardiac studies?

A

6th generation

188
Q

Good quality control measures for CT to monitor function can occur ___

A

daily, weekly, and biweekly

189
Q

the terms pitch and or indexing refer to the…

A

table movement

190
Q

the number assigned by the computer to indicate the density of a tissue is called the

A

CT number/hounsfield number

191
Q

which of the following is not an interventional CT study?

A

WBC scan BUT abscess drainage, biopsy, and cyst aspiration ARE

192
Q

Which of the following is/are a route for contrast media during a CT scan?

A

IV, oral, and retrograde

193
Q

The scan diameter is also called the

A

field of view

194
Q

Which of the following can cause artifaccts on a CT scan?

A

residual GI barium, large density differences between tissue and dental fillings

195
Q

the 4 main quality factors are…

A

artifats, contrast resolution, spatial resolution, noise

196
Q

The depth thickness in CTis also a

A

voxel

197
Q

Which of the 3D techniques depict the anatomic relationship between vasculature and visccera?

A

VR

198
Q

the 3D technique that provides depth perception to reconstructed images is allied…

A

SSD

199
Q

which of the following filters are used in CT

A

bowtie

200
Q

The time from the end of CT imaging to image appearance is called the

A

reconstruction

201
Q

each pixel of information in the CT image contains numerical information in ___ units

A

hounsfield

202
Q

all of the following are methods of 3D reconstruction techniques in CT except

A

pixel-voxel reregistration

volume rendering, maximum intensity projection and shaded surface display are

203
Q

The CT systems ability to freeze any motion of the scanned object is termed

A

temporal resolution

204
Q

CT detectors are most commonly ___ detectors

A

scintillation (solid state)

205
Q

the measured x-ray transmission values is called

A

raw data

206
Q

The most common reporting method of dose reporting on present scanner is

A

dose length product (DLP)

207
Q

which of the following can be used as a shield in CT?

A

bismuth filled shield

208
Q

What is the most common matrix size in CT?

A

512

209
Q

Continuous rotation of the x-ray tube in the gantry is possible due to

A

slip ring technology

210
Q

The first CT scanner was made possible through the ___ company and the ___band

A

EMI, Beatles

211
Q

The advantages of multislice spira helical CT scanners are

A

larger detector array, decrease scan time and longer anatomy coverages

test questions (2 decks)

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