Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

CFC > Diagnostic Imaging (1-8) > Flashcards

Diagnostic Imaging (1-8) Flashcards

1
Q

how is the energy of an x-ray related to its wavelength

A

inversely proportional

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

this is a discrete bundle of electromagnetic radiation

A

photon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

these are able to penetrate materials that absorb or reflect visible light, can cause fluorescence in certain materials, and produce an image on photosensitive film

A

x-rays

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what does damage to tissue by x-rays result from?

A
  1. direct interaction with DNA
  2. indirect ionization of water molecules leading to formation of radicals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

name 4 most radiation sensitive tissues; they are actively and quickly dividing tissues

A
  1. bone marrow
  2. epithelial cells of GIT
  3. gonadal cells
  4. embryonic cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

name the x-ray biological effect

probability of damage increases with dose (cancer, genetic effects); no known lower threshold

A

stochastic effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

name the x-ray biological effect

high radiation exposure; damage only over a threshold; severity increases with dose;
erythema, hematopoietic damage, cataract; concern in radiation therapy and nuclear accidents

A

deterministic effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

this is the amount of ionization per mass of air

A

exposure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

name the unit used to measure

exposure

A

C/kg Roentgen R

(amount of ionization per mass of air)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

this is the amount of energy transferred by radiation per mass

A

absorbed dose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

name the unit used to measure

absorbed dose

A

Gray (Gy) = J/kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

this is a measure of radiation and organ system damage in humans: quality factor for different radiation

A

effective dose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

name the unit used to measure

effective dose

A

Sievert (Sv)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the limited effective dose for employees 18+

A

20 mSv / year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the limited effective dose for for trainees 16-18 years old

A

6 mSv / year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the limited effective dose for the general public

A

1 mSv / year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the limited effective dose for pregnant women

A

< 1 mSv for remainder of pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are the 3 exceptions to vet radiation protection regulation that small animals should be sedatd and restrained with sandbags

A
  1. critical illness where sedation would deteriorate condition
  2. specific technique requiring presence
  3. patient type (LA)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

name 6 methods of radiation protection

A
  1. indication
  2. filtration of x-ray tube
  3. time
  4. distance
  5. shielding
  6. collimation
  7. personnel monitoring
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

name the law

if the distance from the primary source is doubled, the intensity will decrease by a factor of 4

A

inverse square law

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what 3 items must be worn for shielding (radiation protection)

A
  1. lead apron
  2. lead gloves
  3. lead thyroid collar
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

how thick must the lead be for aprons to protect againt radiation

A

0.25 mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

how thick must the lead be for gloves to protect againt radiation

A

0.35 mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

name the method of radiation protection

this is the reduction of the exposed area to the area of interest;
reduces the amount of scatter radiation

A

collimation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

name 2 types of dosimeter

A
  1. film badge
  2. thermoluminescent (TLD)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

how often should dosimeters be analyzed

A

at least quarterly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

how are x-rays produced

A

conversion of kinetic energy of accelerated electrons into electromagnetic radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

where does production, acceleration and deceleration of electrons take place for x-rays?

A

w/in the x-ray tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is the source of electrons for x-rays

A

cathode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what causes acceleration of electrons for x-rays

A

potential difference

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what causes deceleration of electrons for x-rays

A

anode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

how much of the energy in the x-ray tube is converted to x-rays? and what is the rest converted to?

A

<1% x-rays
99% heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what unit is the x-ray tube current measured in?

(number of electrons flowing per second from filament to target)

A

mA (milliamperes x seconds)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what unit is the potential difference in the x-ray tube measured in

A

kVp (kilovolt peak)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what is the best angle for the anode in an x-ray tube

A

6-20 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

if KVp for an x-ray beam is increased, what other 3 things will increase?

A
  1. electrons velocity
  2. number of x-ray photons produced
  3. energy (penetrating power of each x-ray photon)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

if mA is increased for an x-ray beam, what other 2 things will increase?

A
  1. filament heating and tube current
  2. number of x-rays being produced
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

name the interaction of x-rays with matter

this is the decrease in intensity of an x-ray beam as it passed through matter

A

attenuation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

name the interaction of x-rays with matter

when a photon is removed from the beam

A

absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

name the interaction of x-rays with matter

when a photon changes direction

A

scatter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

name the interaction of x-rays with matter

x-ray passes through matter without interaction

A

transmission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

name the effect

complete absorption of x-ray photon; photoelectron removed from shell; electron from higher shell falls into space

A

photoelectric effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

name the x-ray effect

incoming photon ejects free outer shell electron from the tissue atom, photon is scattered; scattered photon has lower energy but may produce ionizations, fog the film and is a radiation safety hazard; results in almost all scatter radiation

A

compton effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

the photoelectric effect of x-rays is the prdominant interaction in what range of kVp radiation?

A

low range (up to 30 kVp)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

the Compton effect of x-rays is the predominant interaction in what kVp range?

A

high kVp range

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

this reduces x-ray scatter to produce a diagnostic quality radiograph; requires increased exposure

A

grids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

name the type of radiographic image acquisition

uses x-ray film, casssetes with intensifying screens, automatic/manual film processor, view box for film review, and an archive for film filing

A

conventional radiography

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

name the layers of a double emulsion x-ray film

A
  1. protective coating
  2. silver halide emulsion
  3. polyester base
  4. silver halide emulsion
  5. protective coating
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

name the components and ratios of silver halide crystal in a double emulsion x-ray film

A
  1. 2% Silver ion (Ag+)
  2. 98% bromide ion (Br-)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

name the 2 parts of exposure effect on silver halide crystals with conventional radiography

A
  1. electron in silver bromide released by light energy
  2. silver atom formation at the sensitivity speck
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

what does ‘sensitivity speck’ refer to in conventional radiography

A

trapped electron (in silver halide crystal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

this image reflects the pattern of the part being radiographed and is views through processing

(conventional radiography)

A

latent image

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

name the part of image processing with conventional radiography

latent image center catalyzes the reaction which reduced the remaining silver ion into grain of metallic silver

A

developer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

name the part of image processing with conventional radiography

prevents further development and removes undeveloped silver bromide from film

A

fixer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

name the part of image processing with conventional radiography

removes fixer chemicals that would otherwise discolor film over time

A

wash (rinse & dry)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

name the effect

the use of an intensifying screen in x-ray film for conventional radiography;
95% of film exposure is from light given off by the intensifying screen

A

fluorescent effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

name 3 reasons to use an intensifying screen with conventional radiography

A
  1. reduce personnel exposure
  2. reduce patient exposure
  3. increased contrast
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

this is used to absorb scatter radiation to imrove radiographic contrast;
recommended when bosy part thickness > 10cm

A

grid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

what must be done to mAs when using a grid with radiography

A

increased by factore of 2-3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

name the type of radiographic image acquisition

image is captures in cassettes containing phosphor storage layer;
cassete put into laser film reader;
computer generates digital image in DICOM which is sent and stored with PACS
(filmless, no chemistry, no darkroom)

A

computed radiography (CR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

name the type of radiographic image acquisition

imaging receptor plate containing many small detector elements transforming x-rays into electrical signal;
images viewed on local workstation then sent to PACS;
detector panel often built into table

A

Direct Digital Radiography (DR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

name the type of radiographic image acquisition

provides moving radiographic images (40 frames/sec); high quality images

A

Dynamic Digital Radiography

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

name 4 advantages of computed radiography

A
  1. time efficient
  2. good image quality
  3. lower radiation dose possible
  4. cost effective
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

name 3 disadvantages of computed radiography

A
  1. laser reader sensitive to dust
  2. maintenance of moving part
  3. manual labor still required
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

name 3 advantages of direct digital radiography

A
  1. image obtained w/in several seconds
  2. good image quality
  3. lower radiation dose possible
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

name 2 disadvantages of direct digital radiography

A
  1. more expensive
  2. more fragile
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

this is where the x-ray tube takes multiple radiographs and fuses images for up to 1.2 m length;
tube rotational and longitudinal rotation to achieve perfect seam of images

A

image stitching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

name 5 advantages of computed and digital radiography (compared to conventional radiography)

A
  1. no acquisition and display flexibility
  2. images are viewable from computers
  3. all image files in DICOM
  4. PACS central digital archive with remote back up data
  5. no fil filing, lost film, dark room, or archive room
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

name 3 features of DICOM

A
  1. unified standard that is vendor independent
  2. both file format and communication protocols
  3. prevents manipulation of image data
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

name 3 features of PACS

A
  1. central storage of images
  2. replaces hard copies film and storage
  3. allows remote access
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

what does DICOM stand for

A

Digital Imaging and Communication in Medicine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

what does PACS stand for

A

Picture Archiving and Communication System

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

List the five radiopacities in order of their opacity

A

Radiolucent (dark)
1. gas
2. fat
3. soft tissue
4. mineral
5. metallic
Radiopaque (light)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

what are orthogonal projections

A

two projections, 90 degrees to each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

this is the enlargement of the radiographic image of an object relative to its actual size;
increased film-subject distance

A

magnification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

this is the partially shaded outer region of the shadow cast by an opaque object;
increases with magnification

A

penumbra

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

this is the misrepresentation of the true shape of an object

A

distortion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

this is the superimposition of structures in different planes

A

summation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

this is two structures of the same radiopacity in contact; their margins cannot be identified

A

border effacement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

the patient right is on this side of the radiograph image

A

left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

the patient rostral/cranial is on this side of the radiograph image

A

left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

name 3 meanings of side markers

A
  1. anatomic left/right side
  2. recumbency (which side down)
  3. lateral margin on CrCd/DP or oblique vies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

name 6 important viewing conditions for digital radiography

A
  1. quite
  2. ambient room lighting
  3. block out extra light
  4. high luminescence and high def monitor
  5. uninterrupted
  6. not tired/stressed/busy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

name 5 things to check for evaluation of radiographic quality

A
  1. exposure
  2. collimation
  3. patient positioning
  4. phase of respiration
  5. patient factors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

name the 5 Roentgen Signs

A
  1. size
  2. shape
  3. opacity
  4. location
  5. number
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

how to most efficiently use logical and intuitive thinking to interpret a radiograph

A

in combination with each other (first intuitive, then logical)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

systematic search is what type of thinking for radiograph interpretation

A

logical thinking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

pattern recognition is what type of thinking for radiograph interpretation

A

intuitive thinking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

this is what the eye sees

A

vision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

this is what the brain sees

A

perception

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

this is the mental completion of incomplete contours based on expected shapes;
creates false organ visibility on radiographs

A

subjective contours (perceptual distortion)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

this is where alternative perceptions can both be seen, but not at the same time;
bias towards the expected perception

A

multistability of perception

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

this is the degree of perceptible difference between two color tones

A

image contrast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

name the colors seen in high image contrast

A

black and white

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

name the colors seen in low image contrast

A

gray and gray

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

this is the difference in radiographic gray tones between two radiographed structures due to their physical differences

A

object contrast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

this is the ability of an x-ray film to produce a degree of image contrast

A

film contrast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

does fat decrease or enhace radiographic contrast

A

enhances (except in excessive quantities, then decreases)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

does gas decrease or enhace radiographic contrast

A

enhances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

this is a substance applied to patient to enhance the “natural” contrast of the organ of interest

A

contrast medium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

name 2 types of negative contrast media in radiography

A

air, CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

what is the purpose of negative contrast media in radiography

A

outlining of hollow organ walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

name 2 possible adverse effects of negative contrast media in radiography

A
  1. overdistention & rupture
  2. gas embolism (with air)
105
Q

name 2 types of positive contrast media in radiography

A

Barium Sulphate & Iodinated Compounds

106
Q

this type of contrast media in radiography has a high absorption of x-rays and is therefore very radiopaque

A

positive contrast media

107
Q

this type of contrast media in radiography does not absorb x-rays and is therefore radiolucent

A

negative contrast media

108
Q

name 3 purposes of positive contrast media in radiography

A
  1. outlining of internal surface of hollow organs, vessels and ducts
  2. organ displacement
  3. filling defects
109
Q

name the type of positive contrast media in radiography

outlines wall and lumen of GI tract (coats mucosa), outlining of mass effect;
biologically inert, not hypertonic, metabolized or absorbed

A

barium sulphate

110
Q

name 2 adverse effects of barium sulphate as a contrast medium in radiography

A
  1. causes granuloma/adhesion in peritoneal cavity
  2. aspiration
111
Q

name the type of iodinated contrast media

dissociates into cations and anions; hyperosmalar

A

ionic contrast media

112
Q

name the type of ionidated contrast media

do NOT dissociate; iso- or low osmolar, slightly more expensive

A

non-ionic contrast media

113
Q

what defect occurs in positive contrast?

structures surrounded by positive contrast will appear lucent if less opaque than contrast media (structures change their relative opacity!)

A

filling defect

114
Q

what is the advantage of using both positive and negative contrast media? (double contrast studies)

A

highlight mucosal detail with positive contrast while providing dark background with negative contrast

115
Q

this is when contrast medium is injected into the subarachnoid space to outline the spinal cord

A

myelography

116
Q

what contrast media is used intravenously in computed tomography (CT)

A

iodinated contrast media

117
Q

what contrast media is used in magnetic resonance imaging (MRI)

A

paramagnetic substances (rare earth metals, Gadolinium)

118
Q

what contrast media is used in ultrasound

A

agitated saline (cheap) OR encapsulated microbubbles (expensive)

119
Q

name 6 uses of musculoskeletal imaging

A
  1. lameness
  2. pain
  3. swelling
  4. localized mass
  5. known trauma
  6. screening tool
120
Q

name 5 prinicples of interpretation for musculoskeletal radiology

A
  1. adequate projections
  2. appropriate centering and collimation
  3. appropriate exposure
  4. examine ‘full image’
  5. consider distribution of changes
121
Q

name the part of the long bone

this is the outer layer of the bone (you don’t see it on radiology)

A

periosteum

122
Q

name the part of the long bone

this is the actual bone that is seen on the radiograph

123
Q

name the part of the long bone

this is the inner layer lining the bone (don’t see it on the radiograph)

124
Q

name 5 soft tissue changes that can be seen with musculoskeletal radiography

A
  1. generalized or localized swelling
  2. masses
  3. calcification
  4. wounds
  5. joint effusions
125
Q

name 6 responses of bone to insult

A
  1. new bone formation
  2. osteosclerosis
  3. osteolysis
  4. bone atrophy
  5. osteopenia
  6. fractures
126
Q

name the type of new bone formation

new bone at joint surfaces;
increased stability to an unstable joint

A

osteophytosis

127
Q

name the type of new bone formation

related to ligament/tendon attachments;
increased strength of an attachment;
can be an indication of soft tissue disease;
includes spondylosis deformans

A

enthesophytosis

128
Q

name the type of new bone formation

resulting from stimulation of the periosteum (trauma, chronic irritation, bone healing, infection, neoplasia);
typically takes 7-10 days to form;
can indicate the aggression of teh disease process

A

periosteal reaction

129
Q

name the 5 forms of a periosteal reaction

A
  1. smooth
  2. lamellated
  3. palisading
  4. irregular
  5. spicular/’sunburst’
130
Q

name the type of new bone formation

an excessive growth of bone

A

hyperostosis

131
Q

name the resoponse of bone to injury

increase in bone density without a change in shape;
leads to increased opacity on a radiograph;
as a result of Wolff’s law;
adaptive respose to increased loading

A

osteosclerosis

132
Q

state Wolff’s Law

A

bone of healthy person/animal will adapt to loads under which it is placed

133
Q

name the resoponse of bone to injury

seen in infection, neoplasia or chronic inflammation

A

osteolysis

134
Q

name the resoponse of bone to injury

chronic slow growing lesions (cysts and benign neoplasia) can exert chronic pressure on adjacent bone; results in thinning and deviation of adjacent bone structures

A

bone atrophy

135
Q

aggressive or non-aggressive bone lesion?

long zone of transition
loss of cortex
marked periosteal reaction

A

aggressive

136
Q

aggressive or non-aggressive bone lesion?

well circumscribed lesion
cortical expansion/thinning
no periosteal reaction

A

non-aggressive

137
Q

name the resoponse of bone to injury

a reduction in bone mineral density; leads to reduced opacity on a radiograph

A

osteopenia

138
Q

name the 2 types of osteopenia

A
  1. metabolic
  2. disuse
139
Q

name 3 types (causes) of bone fractures

A
  1. traumatic
  2. pathological
  3. fatigue (stress)
140
Q

list the 5 steps of bone fracture healing

A
  1. hematoma formation
  2. woven bone + cartilage
  3. ossification of cartilage
  4. lamellar bone
  5. recontoures lamellar bone
141
Q

whta 5 things should be assessed with fracture healing

A
  1. reduction
  2. alignment
  3. implants
  4. soft tissues
  5. bone healing
142
Q

name the term

inflammation of bone with medulla

A

osteomyelitis

143
Q

name the term

inflammation of bone without medulla (skull, phalanx 3)

144
Q

name 4 sequestrum of infectious osteomyelitis

A
  1. small avascular bone fragment from fracture
  2. serves as nidus for infection
  3. surrounding new bone: involucrum
  4. drainage hole: cloaca
145
Q

name 5 examples of radiological evidence of joint disease

A
  1. osteophytosis
  2. alterations in the subchondral bone
  3. altered joint space
  4. subluxation/luxation
  5. periarticular structures
146
Q

name the 5 steps of image formation in ultrasound

A
  1. pizoelectric crystals in probe emit pulse of sound
  2. sound travels through patient
  3. reflected sound returns to probe
  4. a dot is produced on gray-scale image
  5. multiple dots make complete image
147
Q

give the equation for velocity in ultrasound

A

velocity = frequency x wavelength

148
Q

give the equation for frequency in ultrasound

A

frequency = velocity / wavelength

149
Q

what is the assumed velocity of sound through tissue

(ultrasound)

150
Q

what does attenuation mean?
ex: when sound is propagated through a medium it undergoes attenuation

A

loses strength

151
Q

the higher the frequency, the (more or less?) sound beam absorption?

152
Q

absorption of ultrasound beams results in what type of energy?

A

thermal energy

153
Q

the amount of sound beam returned depends on what of adjacent tissues

A

acoustic impedence

154
Q

what is the equation for acoustic impedance?

A

acoustic impedance = tissue density x tissue sound velocity

(Z = PV)

155
Q

what material has the lowest acoustic impedance and therefore slowest velocity of sound?

156
Q

what material has the highest acoustic impedance and therefore the fastest velocity of sound?

A

bone (skull)

157
Q

what two materials in the body act as barriers to ultrasound due to their large differences in acoustic impedance?

A

bone and air

158
Q

this is the ability of a transducer to differentiate two adjacent individual structures

A

resolving power (resolution)

159
Q

name the 2 types of resolution

(ultrasound)

A
  1. lateral
  2. axial
160
Q

name the type of resolution (ultrasound)

the ability to distinguish 2 objects parallel to the sound beam OR 2 objects behind each other

A

axial resolution

161
Q

name the type of resolution (ultrasound)

the ability to distinguish 2 objects perpendicular to the sound beam OR 2 objects next to each other

A

lateral resolution

162
Q

the (longer or shorter?) the wavelength, the better the resolution

(ultrasound)

163
Q

(increasing or decreasing?) frequency improves resolution?

(ultrasound)

A

increasing

164
Q

this is when the beam converges at a specified distance to improve lateral resolution

(ultrasound)

A

focal zone

165
Q

in this mode of ultrasound, returning signals are displayed as grey dots on a screen with echo intensity displayed as dots of brightness on the screen

A

B mode (brightness mode)

166
Q

in B mode of ultrasound, black dots mean this

167
Q

in B mode of ultrasound, grey to white dots mean this

A

many echoes

168
Q

in this mode of ultrasound, moving structures with a strip recording made at right angles to the B mode display;
used especially in echocardiography

A

M mode (motion mode)

169
Q

in this mode of ultrasound, sound is reflected at different frequencies from moving objects;
RBCs act as small reflectors

A

Doppler mode

170
Q

what does the color blue mean on color doppler mode of ultrasound

171
Q

what does the color red mean on color doppler mode on ultrasound

172
Q

name the U/S echoginecity pattern for no returning echoes - black

A

anechoic echo pattern

173
Q

name the U/S echoginecity pattern forlow intensity returining echoes (dark grey)

A

hypoechoic echo pattern

174
Q

name the U/S echoginecity pattern for high intensity returning echoes (appears very light - grey/white)

A

hyperechoic echo pattern

175
Q

name the U/S echoginecity pattern for same number of returning echoes as adjacent tissues; used to compare two structures to each other

A

isoechoic echo pattern

176
Q

name the U/S echoginecity pattern for when echoes are of the expected intensity

A

normoechoic echo pattern

177
Q

name the U/S echoginecity pattern for multiple mixed hyperechoic, hypoechoic, and anechoic echo patterns

A

complex echo pattern

178
Q

list the 3 machine assumptions that lead to US artifacts

A
  1. sound only travels in stright lines
  2. sound travels at a constant speed
  3. returning echoes only result from objects located along the transducer axis
179
Q

name the U/S artifact

fluid structures attenuate less sound, resulting in a greater beam strength beyond the fluid structure making that area more echogenic ;
allows us to tell teh difference between fluids and solids

A

acoustic enhancement

180
Q

name the U/S artifact

certain substances absorb all of the sound beam at an acoustic interface leaving an anechoic area beyond the substance (ex. bone);
allows us to ID dense structures

A

acoustic shadow

181
Q

name the U/S artifact

occurs when sound beam travels at a different velocity at the edge of a rounded structure;
sound beam becomes bent and does not return to the trasnducer;
normal finding

A

refractive and reflective shadows

182
Q

name the U/S artifact

where an acoustic interface reflects so much sound that the transducer/skin interface reflects the sound back into the body again so the structure is assumed to be twice as deep;
may be repeated several times resulting in multiple echogenic equidistant lines

A

reverberation arifacts

183
Q

reverberation artifacts in U/S are most likely to occur with what material

184
Q

name the U/S artifact

Sound reflected from a curved interface
is reflected by another interface before returning to the transducer via the original highly reflective interface

A

mirror image artifacts

185
Q

what two rules must be met for a mirror image artifact to occur in U/S

A
  1. presence of a highly reflective interface
  2. presence of a highly curved convex/concave structure
186
Q

name the U/S artifact

false debris in the urinary or gallbladder (pseudosludge)

A

slice thickness artifact

187
Q

name the U/S artifact

only show up against fluid-containing structures such as the urinary bladder;
scanning in different planes confirms their artifactual nature

A

side lobe artifact

188
Q

this knob allows amplitudes of all the echoes on an U/S to be intensified or suppressed

A

overall gain

189
Q

this allows all of the image to have the same intensity on the screen;
acoustic interfaces deep within the body will be amplified & those close to transducer may be supressed resulting in a homogenous screen image

(ultrasound)

A

selective gain / time gain compensation

190
Q

name 5 main vet application of U/S

A
  1. abdominal U/S
  2. thoracic U/S
  3. tendon U/S (equines)
  4. reproductive U/S
  5. echocardiography
191
Q

name 3 major advantages of U/S

A
  1. safe
  2. non-invasive
  3. low running costs after initial outlay
192
Q

name 3 disadvantages of U/S

A
  1. operator dependent
  2. only sonographer at time of scan can tell how the probe is held relative to the patient
  3. cannot penetrate bone or gas so not all tissues accessible
193
Q

name the 5 main components of a CT unit

A
  1. x-ray tube
  2. gantry
  3. fan-shaped detector row
  4. movable patient couch
  5. computer & workstation
194
Q

name the CT mode

x-ray tube and detectors perform one rotation around patient who does not move;
results in many differently angled attenuation values from which a matrix image is reconstructed

A

sequential/axial mode

195
Q

how many Hounsfield units (HU) is air for CT

196
Q

how many Hounsfield units (HU) is water for CT

197
Q

define voxel (in terms of CT slice)

A

volume element

198
Q

define pixel (in terms of CT slice)

A

picture element

199
Q

name the CT mode

continuous rotation of the x-ray tube detector set, patient moves through gantry during tube rotation;
results in volume data set;
allows faster scanning and reduction of motion artifacts

A

helical/spiral mode

200
Q

the ‘stretch’ of the helix in helical/spiral CT mode is called this;
it is a unitless ratio = table movement/slice thickness during one rotaion of the x-ray tube

201
Q

the slower the pitch in helical/spiral mode CT, the (better or worse?) quality of image

202
Q

name the type of CT

multiple rows of detectors (up to 1000), allows larger coverage of a larger body area per tube rotation with thin slice width;
data from each thin detector row can be processed separately as thin slice images or binned/fused as thick slice images

A

multi-slice/multi-detector-row CT

203
Q

thick or thin slice CT images?

high spatial resolution & sharpness (important for bone)
relatively noisy

A

thin-slice CT images

(0.3-1mm)

204
Q

thick or thin slice CT images?

high contrast resolution (important for soft tissue)
reduced noise

A

thick-slice CT images

(2-5mm)

205
Q

name the type of CT

uses large plate of flat panel detectors;
images are reconstructed as a volume of 3D data (not slice-by-slice);
results in isometric resolution in any image plane, has higher spatial resolution but slower rotation time of the tube;
normal electric plug;
very good for bone and teeth

A

cone beam CT (CBCT) / flat panel detector CT (FPCT)

206
Q

name 5 advantages of cone beam/flat panel detector CT over multislice CT

A
  1. less expensive
  2. mobile
  3. units custom-made for animals
  4. good image quality for bone and teeth
  5. technically higher spatial resolution
207
Q

name 3 limitations of cone beam/flat panel detector CT compared to multislice CT

A
  1. poor image quality for soft tissue
  2. risk of motion artifact (slow tube rotation)
  3. involves ionizing radiation
208
Q

define window center in CT imaging

A

brightness

209
Q

define window width in CT imaging

210
Q

what size window width do nose, lung, and bone require in CT viewing

A

wide window

211
Q

what size window width do soft tissue, brain and post contrast studies require for CT viewing

A

narrow window

212
Q

name the type of CT

CT performs repeated, fast, back-and-forward scans over length determined by scanner; computer merges all individual scan data into one space and time-resolved data set

213
Q

name 3 applications of 4D-CT

A
  1. canine ureter anatomy (ectopic ureters)
  2. ECG-gated CT
  3. perfusion CT
214
Q

name the type of CT

image acquisition triggered by ECG;
continuous scanning through multiple cardiac cycles;
restrospective segmentation into different phases of the cycle (ideally 10% segments)

A

ECG-gated CT

215
Q

name the type of CT

allows perfusion assessment of parenchymal organs during contrast bolus injection;
based on 4D-CT technology
main uses: brain, liver, kidneys, neoplasia

A

perfusion CT

216
Q

name 2 causes of decreased cerebral perfusion

A
  1. infarction
  2. compression
217
Q

name 2 causes of increased cerebral perfusion

A
  1. neoplasia
  2. inflammatory lesions
218
Q

name the diagnostic imaging technique

patient is placed in a magnet, a radiowave is sent in, the radiowave is turned off, the patient emits a signal which is recieved by coils;
the signal emitted by the patient is used to create the picture

A

MRI (magnetic resonance imaging)

219
Q

what type of magnet is used in an MRI scanner?
(electromagnets where an electrical current is passed through a superconducting material)

A

superconductive magnets

220
Q

what must the wire in an MRI be bathed in?

A

a cryogen (liquid helium or liquid nitrogen)

221
Q

name the type of MRI coil

emit radiowaves

A

transmitter coils

222
Q

name the type of MRI coil

recieve signal emitted from patient

A

reciever coils

223
Q

these have a positive charge, spin around their central axis, and generate an electrical current (have their own magnetic field);
used in MRI

224
Q

spin-up or spin-down?

a proton that is aligned parallel with the direction of the external magnetic field (B0)

225
Q

spin-up or spin-down?

a proton that is aligned anti-parallel to the direction of the external magnetic field (B0)

226
Q

which proton orientation in a magnetic field requires less energy and is therefore preferred

227
Q

why are hydrogen protons used in MRI?

A

naturally abundant in tissues & have strong magnetic dipole moment

228
Q

if the total number of protons and neutrons is even, what is teh magnetic moment?

229
Q

within a stong external magnetic field, protons not only line up, but als orotate eliptically like a spinning top - what is this called

A

precession

230
Q

this is the number of times a proton precesses per second

A

Larmor frequency

231
Q

what is the Larmor equation

A

Larmor frequency (MHz) = gyromagnetic ratio x magnetic field strength (T)

232
Q

the srtonger the magnetic field, the (lower or higher?) the precession frequency

233
Q

what is the gyromagnetic ratio for hydrogen protons?

A

42.5 MHz/T

234
Q

what vector(s) is the longitudinal component of protons

A

Z (direction of B0)

235
Q

what vector(s) is the transverse component of protons

236
Q

what frequency is the radiofrequency pulse sent in MRI

A

at the Larmor frequency

237
Q

what 2 things do protons start doing simultaneously as soon as the RF pulse is switched off?

A
  1. longitudinal relaxation (losing energy and returning to spin-up)
  2. transverse relaxation (dephasing)
238
Q

this is the time taken for all of the protons that became spindown to become spin-up again

A

longitudinal relaxation time (T1)

239
Q

longitudinal relaxation time (T1) is the time taken for the longitudinal magnetization to recover to what percent of its maximum value?

240
Q

the shorter the T1, the (quicker or slower?) the protons exchange therman energy with the lattice

241
Q

do liquids have a long or short longitudinal relaxation time (T1)

242
Q

does fat have a long or short longitudinal relaxation time (T1)

243
Q

this is the time taken for the protons to completely dephase

(MRI)

A

transverse relaxation time (T2)

244
Q

transverse relaxation time (T2) is the time taken for the transverse magnetization to decay to what percent of its maximum value

245
Q

the shorter the transverse relaxation time (T2), the (less or more?) inhomogenous the local magnetic field

246
Q

do pure liquids have a long or short transverse relaxation time (T2)

247
Q

do impure liquids have short or long transverse relaxation time (T2)

248
Q

what is contrast based on in T1W MRI images?

A
  1. T1 characteristics of tissue
  2. short TR (amount of time between successive pulse sequences applied to the same slice)
249
Q

what body material has the shortest T1 and therefore highest signat on TW1 images (brightest)

250
Q

what body material has the longest T1 and thus the lowest signal on TW1 MRI images (dark)

A

CSF/pure fluid

251
Q

what is contrast based on in T2W MRI images?

A
  1. T2 characteristics of tissue
  2. long TE (time between the delivery of the RF pulse and the receipt of the echo signal)
252
Q

what body material has high signal intensity on TW2 MRI images (bright)

253
Q

what body material has intermediate signal intensity on TW2 MRI images (medium brightness)

254
Q

what is the maine indication for MRI

A

neuroimaging

(intracranial and spinal cord diseases)

255
Q

does MRI involve ionizing radiation

256
Q

what is the main safety concern of MRI?

257
Q

name 3 reasons metal is a safety concern with MRI

A
  1. can become a missile
  2. distorts magnetic field (image artifacts)
  3. induces electric current and heat (potential burns)
258
Q

what protection must be offered to patients for MRI?

A

hearing protection

259
Q

what is the recommended settling period for microchips before MRI

CFC (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions