written practical Flashcards
1
Q
failure to refer for imaging =
A
non-feasance
2
Q
who reviews “studies” and gives written explanation of findings? (clinical diagnosis)
A
radiologist
3
Q
X-ray Technician
A
18 month degree with clinicals
speciality certifications available
4
Q
general rules / considerations for imaging
A
- no radiographs for pregnant women
- some risk for development of cancer with repetitive exposure
- use of clinical prediction rules & physical exam used to limit exposures
5
Q
EXAMPLES of clinical prediction rules and physical exam used to limit exposures
A
ottowa ankle rules
non-displaced growth plate fractures
6
Q
clear, focus initiative to ______ pediatric patients exposure to radiographs
A
limit
7
Q
what is a radiography?
A
(x-ray)
electromagnetic radiation passed thru a structure
8
Q
what tissue shows up dark in a x-ray?
A
lass dense tissue (soft tissue)
9
Q
what tissue shows up bright white in a x-ray?
A
bony tissue
10
Q
what does an x-ray rule out (R/O) ?
A
fracture
foreign objects
degenerative disk disease
mal-alignments
facet joint dysfunction
11
Q
lungs appear ________ in x-ray
A
dark
12
Q
fat appears ________ in x-ray
A
grey
13
Q
bone appears ________ in x-ray
A
bright white
14
Q
what can be used during x-ray?
A
contrast agent (dye)
but often reserved for MRI and CT
15
Q
when do we need an x-ray?
A
primary uses (indications)
16
Q
considerations for x-ray usage:
A
inexpensive
accessible
quick
generally comfortable
17
Q
ABCs
A
A - assess general skeletal structure
A - assess general contour
B - general bone density
C- cartilage space
18
Q
Assess general skeletal structure
A
- gross size and appearance
- presence of accessory bones
- congenital anomalies
- absence of bones
- deformity
19
Q
Assess general contour
A
- irregular in cortical outlines
- presence of osteophytes
- break in continuity of cortex
- angles in cortex
- muscles, tendon, ligament attachment
- previous surgical sites
20
Q
general bone density
A
- adequate contrast between bone and surrounding
- adequate contrast within bone including distinct cortex
- bone density influenced by age, activity level, disorders
21
Q
texture abnormalities:
A
altered trabecular appearance is hallmark of disease process
22
Q
cartilage space:
A
- well preserved joint space indicates that cartilage is normal thickness
- joint space identified as “potential space” or “radiographic joint space”
- specific to the joint and best measured in WB
23
Q
epiphyseal plate in growing child are . . .
A
cartilaginous
24
Q
why are epiphyseal plates evaluated?
A
for size comparing skeletal maturity to age
25
epiphyseal plate borders bound by . . .
smooth margin with band of sclerosis
26
may need _______________ for comparison
contralateral films
27
radionuclide bone scan
- nuclear imaging
- short-lived radionuclide to assess abnormalities in bone tissue
28
bone scan
- tracer is injected (emits gamma radiation)
- circulates through body (30 m - 2 hrs)
- special camera reveals "hot spots" on bone
- indications
29
what are "hot spots" ?
areas of increased metabolic activity
30
what do bone scans rule out?
fracture, infections, tumors, arthritis
31
fluoroscopy
- ionizing radiation
- allows for "real-time image"
(used during clinical procedures)
- indications/uses are similar to x-rays
- clarity depends on power and type of machine
32
what does PET stand for?
positron emission tomography
33
what is a PET used for?
to examine the cell metabolism and biochemistry of tissue and organs
* used extensively to identify cancers, thyroid conditions, infections, bleeding
34
what kind of injection for a PET scan?
radionuclide injection
35
what does MRI stand for?
magnetic resonance imaging
36
what is an MRI?
- applies a magnetic field to the body (body atoms align along magnetic field, releasing radio wave)
37
MRI indications:
to image organs, soft tissue, bone, tumors, bleeding, inflammation, infection
38
what kind of imaging is used extensively in orthopedics, ortho-spine & neurology?
MRI
39
MRI considerations:
- excessive movement can cause blurry images
- claustrophobia
- no radiation
- cannot have any metal present
- high cost!!
40
what are the two types of MRIs?
T1 & T2
41
T1 weighed image:
fluid: low signal intensity (black)
muscle: intermediate signal intensity (grey)
fat: high signal intensity (white)
CNS/brain:
- grey matter: intermediate signal intensity (grey)
- white matter: hyperintense compared to grey matter (white-ish)
42
T2 weighed image:
fluid: high signal intensity (white)
muscle: intermediate signal intensity (grey)
fat: high signal intensity (white)
CNS/brain:
- grey matter: intermediate signal intensity (grey)
- white matter: hypointense compared to grey matter (dark-ish)
43
MR arthrogram
adds dye into the structure
44
MR arthrogram good for ID of:
- cartilage lesions
- neuro-trauma
45
ultrasound:
uses non-thermal sound wave to image soft tissue structures
clarity depends on machine & level of skill of the technician
46
ultrasound indications:
- image musculoskeletal structures
- used to guide clinical procedures
47
Doppler US:
ID blood flow / obstruction of blood flow (thromboembolism)
48
what does CT stand for?
computed tomography
49
CT scan
- ionizing radiation (larger dose than x-ray)
50
CT of the skull & brain (spinal cord) indications:
non-contrast (most common)
- numerous: stroke, trauma, headaches. tumors seizures, change in mental status
combination of non-contrast & post-contrast study
51
combination of non-contrast & post-contrast is . . .
less common
52
combination of non-contrast & post-contrast is performed when?
brain tumors or abscesses are suspected & patient cannot get MRI
* IV contrast is also given to assess vasculature
53
CT scan of skull/ brain/ spinal cord findings are discussed in terms of __________.
densities
54
white
hyperdense
- bone, calcium deposits, fresh blood, melanin, contrast
55
grey
isodense
- brain parenchyma, glial tumors, subacute blood
56
dark grey
hypodense
- CSF, brain edema, fat, chronic blood
57
black
hypodense
- air
58
MRI of the brain indications:
- confirmation of stroke
- assessment of intracranial tumor
- chronic headache
- seizure disorder
- demyelinating disorder
59
GAD =
gadolinium (multiple sclerosis)
60
MRI of the brain benefits:
- multiplanar assessment
- different sequences allow for assessment of different pathology
- no ionizing radiation (good for children)
61
MRI of the brain limitations:
- much longer study (20-40 minutes)
- less available
- issues with claustrophobic patients
- contraindicated in patients with metallic fragments or implants
62
MRI of the brain findings are discussed in terms of ____________
intensities
63
MRI of brain : T1
fluid is dark
grey matter is darker than white matter
64
MRI of brain : T2
fluid is bright
white matter is darker than grey matter
65
what does FLAIR stand for?
fluid attenuation inversion recovery
66
FLAIR is similar to _____, but . . .
T2
fluid is "suppressed" and is therefore dark
67
what is FLAIR useful for?
assessing edema / inflammation
68
FLAIR involves
DWI (diffusion-weighted imaging)
ADC (apparent diffusion coefficient)
69
what imaging can be used for spinal column?
x-rays
MRI
CT
70
cervical MRI indications:
- neurologic signs & symptoms referable to the cervical spine
- soft tissue injury evaluation
71
neurologic signs & symptoms referable to the cervical spine : assessing for . . .
disc herniation
cervical stenosis
72
soft tissue injury evaluation : assessing for . . .
ligamentous injury
tumors or infections
73
cervical MRI : T1
fluid is dark
74
cervical MRI : T2
fluid is bright
75
what does STIR stand for?
short tau inversion recovery
76
what is STIR?
fat suppression technique that is used to assess for soft tissue injuries
77
thoracic / lumbar x-ray confirm / monitor what?
scoliosis
78
how many lobes does the right lung have? and what are they?
3:
superior
middle
lower
79
how many fissure does the right lung have? and what are they?
2
horizontal
oblique
80
how many fissure does the left lung have? and what are they?
1
oblique
81
how many lobes does the left lung have? and what are they?
2
superior
inferior
