Medical Diagnostics Exam 1 Flashcards

1
Q

Radiation measurements

A
R = roentgen
Rad = Radiation absorbed dose
Rem = Rad equivalent man

For diagnostic radiology purposes
R=Rad=Rem
all the same

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2
Q

colles

A

distal radial fx
foosh
elderly women
kids

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3
Q

Odontoid fx

A

C2 fx
3 types

Top of dens
bottom of dens
through mian part of bone

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4
Q

Ultrasound pearls

A
Pregnancy
intraabdominal
pediatric
cheap
fast
harmless
results vary based on skill of tech
limited scope
worse for high BMI patients
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5
Q

Lunate dislocation

A

FOOSH

palm strike

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6
Q

Spondylosis

A

SPONDLYLOSIS is a bony defect of the pars interarticularis

It happens most often in adolescent athletes and at the L5 vertebrae.

The defect results in formation of a “collar” around the Scotty Dog Model of the lumbar vertebrae

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7
Q

Osteosarcoma

A

• Most common primary malignant bone tumor

70% show evidence of pulmonary metastasis, death usually secondary to respiratory compromise

can be familial

sunburst or codmans triangle

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8
Q

Which of the following findings will prevent you from administering IV contrast

  1. Creatinine 1.8
  2. O2 saturation of 93%
  3. Chronic use of Metformin
  4. Flushing upon prior administration of contrast
A
  1. Creatinine 1.8
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9
Q

Transverse Avulsion Patellar Fracture

A

Caused by indirect force generated by the quadriceps tendon.

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10
Q

radial head fx

A

FOOSH
most common elbow fx in adults

hard to see on xray
look for sail sign or fat pad

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11
Q

Does the “air” appear differently on CT or Xray in terms of contrast

A

No, air looks black and the same in both CT and x ray

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12
Q

Triquetral Fracture

A

2nd most common after scaphoid

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13
Q

Computed tomography CT

A

is x rays constructed by a computer

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14
Q

Bennett Fracture

A

broken / dislocated thumb

twisting hand around a tubular body

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15
Q

shoulder dislocation

A

anterior most common
head down and forward

posterior
Very uncommon and can be easily missed

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16
Q

what does the collimator do

A

Narrows the rays and focuses the x rays

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17
Q

soft tissue imaging

A

MRI

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18
Q

to image soft tissue

A

low kVp

low mAs

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19
Q

Adverse reactions

A

Idiosyncratic vs non idosyncratic

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20
Q

Lisfranc Injury

A

A fracture and or dislocation at the tarsometatarsal joint.

Seen in mountain bikers who get their feet caught in the pedal clips

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21
Q

gold standard of imaging of arterial system

A

angiography (arteriography)

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22
Q

Immobilize yes or no?

A

All suspected and confirmed
fractures need to be
immobilized.

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23
Q

Degenerative Joint Disease

A

Note Osteophyte Formation
• Decreased Joint Space
• Sclerosis
irregular joint spaces

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24
Q

Oral contrast and weight

A

Oral contrast is recommended for people with BMI less than 21 due to lack of fat

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25
Q

MRI pearls

A

Expensive
no radiation
good for pregnant
excellent for soft tissues

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26
Q

Ultrasound colors

A

Solid structures appear white
Cystic structures appear black

Doppler to detect flow
Red towards transducer
blue away from transducer

Echogenicity

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27
Q

SCFE

A

Slipped capital femoral epiphysis
ball head of femur slipps of the neck (broken)
emergency

happens in kids

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28
Q

Tear drop fx

A

diving into pool

tear drop piece breaks off spine

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29
Q

Segond Fracture

A

anterior cruciate ligament tears are
commonly associated with this type
of fracture

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30
Q

CT artifacts

A

Movement
Dust particles
foreign bodies

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31
Q

Which cervical injury mandates neurosurgery consultation in
absence of any neurovascular compromise?

  1. Clay Shovelers Fracture
  2. Wedge Fracture
  3. Odontoid Fracture
  4. Compression Fracture
A
  1. Odontoid Fracture

due to being unstable fx

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32
Q

tomography

A

Same as x ray except the x ray tube and the film move at the same time

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33
Q

Scoliosis image

A

must have whole spine in film to see diffenret angle of rotation

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34
Q

MRI signal strength image

A

Strong image will appear white (high intensity)
fluid

Weak signal wil appear gray (low intensity)
Soft Tissue

No signal will appear black
Air, bone (very dense)

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35
Q

how is radiation absorbed

A

it differs depending on the type of tissue
Bone and tissue absorb differently

Measured in sieverts

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36
Q

CEUS

A

Contrast Enhanced Ultrasound
Microbubble contrast agents smaller than RBC’s
Enhance doppler imaging

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37
Q

Pelvic sacrum trauma

A

severe pelvic truama is associated with hemorrhage 60% of the time

it is the main cause of death in this population

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38
Q

metformin and contrast

A

must stop metformin until 2 days after contrast due to the high rate of lactic acidosis

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39
Q

What is the ideal combination of kilovoltage and milliamperes per second when evaluating soft tissues on an xray?

  1. High kVP, High mAs
  2. Low kVp, High mAs
  3. High kVp, Low mAs
  4. Low kVp, Low mAs
A
  1. Low kVp, Low mAs
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40
Q

Adverse reactions

MIld - moderate - severe

A

Mild - N/V , flushing

moderate - uticaria, bronchospasm, vasovagal

Severe (rare) - seizures, Altered mental state, Cardiac arrest

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41
Q

Unilateral Facet dislocation

A

Facet joint dislocation and rupture of the apophyseal joint ligaments resulting from rotatory injury of the cervical vertebrae: simultaneous flexion and rotation.

Could be confused with spondylolisthesis

(spondylolisthesis usually occurs in lower back, not c spine)

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42
Q

Imaging costs

A

CT 51 & 1565
xray and US 55 & 410
Nuc med 135 & 1138
MRI 165 & 2048

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43
Q

Malignant Bone Tumor

A

Primary, Metastatic Moth eaten
or permeative appearance to
margins

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44
Q

Malgaigne Fracture

A

Articular or para-articular
fracture of the sacroiliac joint
and ipsilateral ischiopubic rami.

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45
Q

Multiple myeloma

A

Males, AA, over 45
common to kidney disease

punched out lesions (russel bodies)

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46
Q

Burst fx

A

crushed vertebral body

compression fx

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47
Q

Luxatio Erecta Shoulder Dislocation

A

Arm dislocated straight up

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48
Q

Radiopaque vs radiolucent

A

Radiopaque is radio dense / structures appear white

Radiolucent / structures appear black

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49
Q

Adverse reactions

Non - Idiosyncratic

A
occur rapidly
can have metallic taste
warth / flushing
urge to urinate
bradycardia, hypotension, vasovagal

can lead to vascular collapse / death

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50
Q

Nuclear medicine agents

A

Technetium 99m (bone)

Gallium 67 Inflammatory disorders (tumors)

Indium 111 WBC (acute infections)

Labeled WBC

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51
Q

Benign Bone Tumor

A
  • Well demarcated (round/oval)

* Narrow zone of transition

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52
Q

A 5yo female is in your office for evaluation of fall and elbow injury. Lateral elbow xray reveals posterior fat pad or Sail signs, which is an indication of what condition?

  1. Dislocation
  2. Hemarthrosis
  3. Sprain
  4. Contusion
A
  1. Hemarthrosis
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53
Q

Gout

A

red hot swollen joint
podagra
rat bite erosions

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54
Q

Imaging

A

Film is fragile, flammable, wrinkles and gets moldy

Most imaging today is digital

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55
Q

Osteomyelitis in Diabetics

A

• 94% of cases of diabetic osteomyelitis in the foot are
associated with ulcers. So if an ulcer is absent, osteomyelitis is
unlikely

Charcot (Neuropathic Joint)

MRI gold standard (acute)

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56
Q

Dexa Scan

A

Dual Energy Xray Absorptiometry

Used for osteoporosis diagnosis

Used to determine bone mineral density (BMD)

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57
Q

Arthrography

A

Imaging of a joint with contrast

can be injected with iodine contrast or air

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58
Q

Scottie dog sign

A

normal appearance on lumbar imaging

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59
Q

radiation proteciton

A

gold is best protector

lead is used due to cost

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60
Q

When is the swimmers view useful

A

heavy people

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61
Q

Calcaneal Fracture

A

lovers fx

fall from height

62
Q

GRUM

A
Galleazi = Radius
Ulna = monteggia
63
Q

C spine soft tissue measurements

A

Area Adult Child

Predental space < 3mm < 5mm

Retropharyngeal space < 7mm < 7mm
(anterior to C3)

Retrotracheal space < 22mm < 14mm
(anterior to C6)

64
Q

Adverse reactions

Idiosyncratic

A
Happen for no reason
unpredictable
usually within 20 minutes
can occur with as little as 1 ml
prior sensitivity testin of no value

can go from mild to severe

65
Q

patella fx

A

sunrise view

66
Q

MRI T1

A

T1 images

White Matter appears white, gray matter appears gray, CSF is black

Best for normal anatomy
Fat and bone marrow appear bright

Tendons, ligaments, cortical bone, and air always appear black
because of their lack of water content

67
Q

Femoral neck fx

A

in osteoporosis patients
the bone breaks then they fall

associated with meonpuase

avascular necrosis occurs about 10-30% of the time

John thomas sign

68
Q

How long should you avoid iodine contrast before Iodine 131 is given for thyroid ablation

A

2 months

69
Q

scaphoid fx

A

most common fx carpal
FOOSH, extreme dorsalflexion
avascular necrosis can occur

70
Q

Arterial duplex

A

Arterial occlusive disease

71
Q

BERT

A

Background equivalent radiation time

This increases with altitude

a single transcontinental roundtrip flight is equal to 2.5 chest xrays

Measured in sieverts

72
Q

Shaken baby

A

Skull and C1 seperation

73
Q

Color doppler US

A

for flow and turbulence

74
Q

Metastatic Bone Tumors

A

Metastatic bone tumors are much more prevalent than
primary bone tumors

most common originate from five organs:
breast, kidney, lung, prostate, and thyroid.

Generally, if there are “hot spots” in asymmetric areas in such
patients, the radiologist assumes they represent metastases

75
Q

Maisonneuve Fracture

A

Fracture of the proximal half of
the fibula.

strong eversion at
the ankle joint.

76
Q

Is flexion C-Spine xray appropriate if you suspect teardrop fracture?

A

NO

never flexion or extention in c spine fx

77
Q

Tillaux Fracture

A

Lateral margin avulsion of the

distal tibia.

78
Q

You are evluating a patient following MVC with suspected ligament injury. What imaging modality will best evalutate this pathology?

  1. Xray
  2. CT
  3. Ultrasound
  4. MRI
A
  1. MRI (proton density) (flair)

CT is good, but MRI is better

79
Q

Nuclear medicine

A

uses radioactive substance

expressed as high or low intensity
hot or cold
hot appears black
cold appears white

80
Q

Rheumatoid arthritis

A

MRI early, xray late in disease

81
Q

Hangmans fx

A

C2
hitting windshield

pars interarticularis fx

82
Q

US Artifacts

A
Mirror image
Acoustic shadow
Acoustic enhancement
Reverberation
Refraction
83
Q

lower extremity

A

soft tissue injuries are most
then FX
then dislocations

84
Q

Greenstick 3 types

A

transverse (fx halfway across bone)
torus (buckling, overlap)
bowing (bent without crack)

common in abuse

85
Q

In suspected perforation what contrast should you give

A

Gastrografin

It is water soluble and can be diluted

Doesn’t coat mucosa as well as barium

86
Q

pretreatments for allergic reactions

A

prednisone 50mg

benadryl 50mg

87
Q

Contrast ordering

A

Bony abnormalities, pneumonia = none
Soft tissue trauma = IV contrast
Cellulitis, infection, inflammation = IV contrast
PE, aortic dissection, renal stones= with or without
bowel abnormalities = with oral contrast

88
Q

What is a normal predental space in an adult c-spine evaluation?

  1. < 3 mm
  2. < 5 mm
  3. < 7 mm
  4. < 14 mm
A
  1. < 3 mm
89
Q

Creatinine level to receive IV contrast

A

creatinine 1.4 to 1.7

depends where you work

higher wont get IV Contrast

90
Q

Salter-Harris IV

A

Second most common SH Fx

• Extends through epiphysis,
physis, and metaphysis

• Can result in disability

• Usually will require surgical
repair

91
Q

scapula fx

A

force to break scaupla warrants a CT

92
Q

Thurston-Holland Sign

A

A triangular
metaphyseal fragment seen in
Salter-Harris type II fractures

93
Q

Radiation monitoring

A

Thermoluminescent dosimeter
= 3 months, more expensive
not as common

Film Badges
= 1 month
less expensive
more common

94
Q

MRI imaging weighting

A

T1 short TR, Short TE
T2 Long TR, Long TE

2 is greater than 1

95
Q

How to protect from ionizing radiation

A

reduce time
increase distance
shielding
Collimate (focus the beam)

Increasing the distance is the most effective way to limit radiation exposure

96
Q

Ewing Sarcoma

A

Primary malignant bone tumor
– Highly metastatic

Most common malignant bone tumor seen in children

onion skin, hair on end

97
Q

3 images angles for C spine

A

Lateral,
AP,
odontive

98
Q

Flouroscopy

A

Mobile xray
generates realtime continuos results
adjustable x ray beam
visualization of anatomical structures in real time

99
Q

Gadolinium

A

Gadolinium Deposit Disease
2017
neurovascular complications
neuropathic pain

Nephrogenic system fibrosis
Renal impairment
2-10 weeks

100
Q

Posterior hip dislocation

A

trauma
90% are posterior
sciatic nerve issues in 10%

101
Q

MRI T2

A

T2 images

CSF is white, Fatty structures are darker

Best for pathology, Water, edema, acute hemorrhage appear bright

Tendons, ligaments, cortical bone, and air always appear black
because of their lack of water content

102
Q

Spondylolithesis

A

Anterior slipping is termed SPONDYLOLISTHESIS.

103
Q

Osetomyelitis

A

Bone erosion and destruction

DDX
iv drugs, neck/back pain

104
Q

Ethical principles of radiology

A

Autonomy
Beneficience
Nonmaleficence
Justice

105
Q

Pagets disease

A

abnormal calcium depostis on bones

106
Q

Ottawa Ankle Rules

A

Presence of point tenderness at either of the 4 spots and inability to bear weight following injury warrants xray imaging.

  1. medial malleolus
  2. lateral malleolus
  3. Navicular Bone
  4. Bas eof 5th metatarsal
107
Q

ALARA concept

A

As Low As Reasonable Acheivable

Radiation limit set by a council

Radiation worker = 5 REMS per year

Average population = 0.5 Rems per year

108
Q

CT on a pregnant woman

A
Do not image in first trimester
abdomen
pelvis
lumbar spine
hips

unless mother is going to die

otherwise choose alternate (MRI, US)

109
Q

Two most important US artifacts

A

Echo of posterior enhancement
Bright band extending from posterior to the weak attenuator
Distinguishes cyst from lesion
y

Shadowing
Decreased posterior attenuation of highly reflective surfaces
Helpful in stones identification

110
Q

Acromio-Clavicular Joint Separation

3 types

A

Type 1 - Partial tear

Type 2 - Disruption of the acromioclavicular ligament

Type 3 - Disruption of the acromioclavicular and coracoclavicular ligaments

111
Q

Wedge Fracture

A

Compression fracture resulting from flexion.

Very common in ED setting

112
Q

2 tyeps of biological effects of radiation

A

Genetic effect
DNA molecules are damaged
can pass on to offspring

Somatic efect
cellular effects
burns, hairloss, cancer etc
not passed on

113
Q

Venous Duplex

A

DVT venous valvular incompetence

114
Q

Clay Shoveler’s Fracture

A

Fracture of a spinous process C6-T1

115
Q

MRI how it works

A

Radio waves excite hydrogen atoms in a patients fat and water molecules

they align themselves with magnetic fields

computer analyzes and reconstructs it

Absorbtion does not matter (radiopaque, radiolucent dont apply)

116
Q

supracondylar fx

A

median nerve
most common in peds
fx above epicondyle

117
Q

Nuclear medicine scans contrasts

A
Tc99m MDP (Methyl Diphosphonate)
Cancer/infection

• Tc99m HMPAO-WBC (Ceretec)
infection

• Indium 111 WBC

all are used for Osteomyelitis in Diabetics and charcot

118
Q

What are L1 fx linked to

A

Calcaneal fx

119
Q

Who discovered x rays

A

Wilhem Rontgen

1895

120
Q

How much radiation is in 1 abdominal CT

A

1 REM
= to 500 chest xrays
or 4.5 years of background radiation

121
Q

Salter-Harris V

A

Epiphyseal plate injury only

• Have poor prognosis and
significantly alter further growth

refer to specialist

122
Q

MRI safe devices

A

Fillings, Braces, IUD’s

Surgical hemostasis clips (2-3months post implant)

123
Q

CT benefits

A

Excellent contrast resolution

Cross sectional images in mostly axial plane

excellent for imaging cortical bone

124
Q

Jones fx

A

Fracture of the base of the fifth
metatarsal, at least 1.5 cm. distal
to the metatarsal styloid.

avascular necrosis

prompt orthopedic follow-up.

125
Q

Osteoid Osteoma

A
Distinctive benign osteoblastic tumor
• Painful
• Pain increased at night
• Classically relieved with aspirin (NSAID)
• Pinpoint tenderness directly over
lesion
126
Q

Tibial Plateau Fracture

A

Occur most often are the result
of a moving vehicle striking the
knee.

127
Q

Preferred imaging for C spine

A

CT

up to 20% of fx missed on xray

(in the field) = crosstable c spine xray

(in ed) = CT w/o contrast

128
Q

Duplex ultrasound

A

Clear Fluid appears black
(anechoic {no echo])

Not clear fluid will apear gray

129
Q

Salter harris III

A

Physis and epiphysis fractures
• Usually requires surgical
intervention

130
Q

Site for Bone mineral density

A

using dexascan
hip and spine to diagnose osteoporosis
forearm also for alternative

uses statistical analysis

131
Q

Radiology team

A
Radiologist
Diagnostic medical physicist
Radiology Assistant
Radiology Nurse
Radiology Tech
132
Q

Bilateral facet dislocation

A

complete anterior dislocation of the vertebral body resulting from extreme hyperflexion injury

133
Q

Amount of radiation required to die in short period of time

A

400 REM

1 REM = 500 chest xrays

134
Q

When should you avoid barium sulfate

A

when perforation or peritonitis is suspected

Barium sulfate not water soluble

135
Q

Radiation in pregnancy

A

embyologic effects
effects on th embyro

first six weeks (first trimester)
most radiosensitve
most severe effects occur during this time

sensitiviy decreases in 2nd and 3rd trimester

136
Q

Galeazzi Fracture

A

proximal radius fx with distal radial dislocation

137
Q

Rolando fx

A

Comminuted (or 3 part) intraarticular fracturedislocation of the base of the thumb (proximal first metacarpal).

Essentially a comminuted Bennett Fracture

138
Q

DM with Charcots foot. Not sure
about osteomyelitis based on
plain xray results.

What imaging study would you
order?

A

WBC scan

139
Q

MRI Contrast

A

Most are gadolinium enhanced to produce “positive” or
enhanced contrast mostly on T1 weighted images.

• T2 effects are negligible

• Types of contrast material
– Extracellular agents
– Blood Pool agents
– Hepatobiliary agents

140
Q

Scottie dog sign with collar

A

SPONDLYLOSIS is a bony defect of the pars interarticularis

looks like collar

141
Q

kVp

A

Kilovoltage (for xrays)

Affects the quality or penetrating power of the beam

differnet kVp depending on what you are trying to image.

142
Q

A68yo AAF presents to your ED for evaluation of fall. On exam
you note right leg shortening and rotation. What is the most
likely pathology expected on imaging?

  1. Comminuted Nondisplaced Femoral Fracture
  2. Hip Dislocation
  3. Patellar Fracture
  4. Hip Fracture
A
  1. Hip Fracture
143
Q

Monteggia Fracture

A

Fracture of the ulna with
accompanying radial head
dislocation.

144
Q

Cells and radiosensitivity

A

Reproductive and WBC are most radiosensitive

Muscle, nerve, bone have low sensitivity

145
Q

psisform fx

A

rare

crush injury

146
Q

best view for assessing soft tissue

A

Lateral view

147
Q

Heterotopic Ossificans

A

extra bone growth

can be caused by trauma or surgery
hip joint replacemtn

148
Q

Jefferson fx

A

C1 fx
crush
broken in places

149
Q

Contrast

A

ateriograms, venograms, ingested contrast

Iodine and barium

IV contrast is always iodine

150
Q

Proximal Tibial Stress Fracture

A

Nuclear bone scanning is more
sensitive for this diagnosis.

helsp diffeentiate between osgood schlatter