問題一覧
1
Merges the xray technology images in a computer
ctscan
2
Xray beams moves in an arc motion surrounding the patient
ctscan
3
Computer reconstruct the images based on the position of the scanner and how much radiation is absorbed
ctscan
4
This allows the computer to determine the type of tissue in the specific area
ctscan
5
CT scan is more sensitive than conventional radiography
true
6
Volume effect: the compiter applies the average values in a specific area, making it less specific in the borders of different tissue boundaries
ctscan
7
Attenuation
ctscan
8
Xrays are emitted and detected at an angle and is measured by how much of the radiation has passed thru or absorbed
attenuation
9
Mathematical algorith allows the reconstruction of the human body
ctscan
10
Attenuation is measured in
hounsfield units, ct number
11
Bone
high density tissue
12
Lungs
low density tissue
13
Absorbs the radiation to a greater degree, and a reduced amount is detected by the scanner on the opposite side of the body
high density tissue
14
Absorbs the radiation to a lesser degree, and there is hreater signal detected by the scanner
low density tissue
15
Black to white substance according to hounsfield value
air, fat, water, blood, bone
16
Study values
ok
17
Parts of ctscan
gantry, data acquisition system, operator console
18
Xray source, collimators and detectors are found in what part of CT scan
gantry
19
Different forms of CT
3D, myelogram, conebeam
20
Combines CT with contrast material
myelogram
21
Employs a large cone shaped beam matched with flat panel detectors
conebeam
22
Results in high speed scans with lower radiation
conebeam
23
Human eye can detect ___ shades of gray vs _____ shades by the computer
32, 256
24
Displaying all hundered of gray shades may appear as one shade in the human vision
true
25
Computers cannot be manipulated to choose the radiodensities to be displayed
false
26
??
bone window
27
??
soft tissue window
28
Introduction of ________ dye allows enhancement of tissues
radiofluorescent
29
Radiofluorescent dye
intravenous for cardiovascular system and tumors, oral contrast for bowel and digestive system
30
Passage thru the urine for CT urogram
intravenous for cardiovascular system and tumors
31
Ctscan with contrast
angiogram, urogram, barium swallow, stonogram
32
Radiofluorescent dye
contrast
33
Uses radiooharmaceuticals for the diagnosis of diseases based in physiological or functional changes of the tissue
nuclear imaging
34
Pharmaceutical moves and concentrates in the speicifc organ and the computer measure the about of gamma radiation emitted in the same area
nuclear imaging
35
Nuclear imaging consists of two parts
pharmaceutical, radionuclide
36
Targets specific organ
pharmaceutical
37
Emits the gamma ray
radionuclide
38
Lung and thyroid scans
static
39
Seen in bone scans
whole body
40
Cardiac, hepatobiliary and gastric studies
dynamic
41
Used to detect perfusion in bone, cardiac, brain and liver
SPECT
42
Measures the metabolism (low or high) to detect tumors
pet scans
43
Used in CNS disorders, dementia and cardiac blood flows
pet scans
44
PET Scan
positron emission tomography scan
45
PET uses ______ as tracers.
drugs
46
Tracers may be swallowed, inhaled or injected. Tracers accumulate in areas of low activities.
first true second false
47
Conjunction of CTScan or MRI =
better imaging diagnosis and location
48
Show up as bright spots on PET scans because they have a HIGHER metabolic rate than do normal cells
cancer
49
In terms of cancer, PET scans may be useful in:
detecting, revealing whether it has spread, checking if treatment is working, find recurrence
50
PET scans must be interpreted carefully because noncancerous conditions can look like cancer, and some cancers do not appear on PET scans
true
51
Solid tumors appear on PET scans:
brain, cervical, colorectal, esophageal, head and neck, lung, lymphoma, melanoma, pancreatic, prostate, thyroid
52
Body is made up of watee
mri
53
Different tissues have different amounts of hydrogen ions
mri
54
Magnets are used to spin the hydrogen ions
mri
55
When magnet is turned off, protons gradual return to their normal state
mri
56
Details of the body is determined by how long it take to return to their normal state
mri
57
Measures the energy emitted by the hydrogen atom where they are stimulated by radiofrequency
mri
58
Alignment of the protons by external magnetic fields
longitudinal magnetization
59
Altering the alignment of the protons
transverse magnetization
60
Realignment and decay
release of energy absorbed during alignment
61
Return to longitudinal magnetization
t1
62
The faster the recovery, the shorter the t1, the stronger the signal
t1
63
Relaxation of the transverse magnetization
t2
64
The slower the decay, the stronger the signal
t2
65
Different tissues have the same decays
false
66
T1
shorter TR and TE times, fat gives high signal intensity, provides images of good anatomical details, water gives low signal intensity
67
T2
water are slow to give up energy hence high signal intensity, long TE and TR times, fat gives up energy easily hence low signal intensity, valuable in detecting inflammation
68
Contast in MRI
gadolinium, excellent in soft tissue details = tumor, stroke, bleeds
69
WHITE T1
fat protein rich fluid
70
T2 white
water content— inflammation, tumor, hemorrhage, infection
71
Intermediate T1
gray spinal matter, darker than white
72
Intermediate T2
white spinal matter, darker than gray
73
Dark T1
bone, air, water content
74
Dark T2
bone, air, fat
75
Shows high signal intensity on T1; low to moderate intensity in T2
acute hemorrhage
76
Shows moderate to high signal intensity on both T1 and T2
subacute hemorrhage
77
Shows variable signal intensity on T1; high signal intensity on T2
chronic hemorrhage
78
Increase freewater content of tissues display
inflammation
79
decreased signal intensity on T1, increased signal intensity on T2
inflammation
80
Associated with rheumatoid arthritis
proliferated synovium
81
Intermediate to high signal intensity
proliferated synovium
82
Often associated with infiltration of the substance of the muscle by fat and fluid
muscle atrophy
83
Increased signal intensity on both T1-T2
muscle atrophy
84
High free water content
soft tissue tumors
85
Low signal intensity on T1, high signal intensity on T2
soft tissue tumor
86
Various signal intensifies depending on the tissue from which they arise and whether they are osteogenic or osteolytic in nature
bone tumor
87
Displayed as straight or serpiginous (worm-like) lines of low signal intensity on both T1 and T2
bone tumor
88
Surrounded by marrow edema, which exhibits low signal intensity on T1 but high signal intensity on T2
acute fracture
89
Display as bone bruises
stress fracture
90
Low signal intensity on T1, high signal intensity on T2 before a fracture line is visible
stress fracture
91
Uses soundwaves to get a picture of the body
ultrasound
92
Requires little to no preparation
ultrasound
93
Harmless to fetus and children
ultrasound
94
No radiation needed
ultrasound
95
Used to study movement of material in the body
doppler
96
Special uses of ultra sound
guide needles during biopsy, identify blood flow, others
97
Ultrasound runs between
2-5 mhz
98
Non invasive, dependent on the skill and interpretation of sonologist
ultrasound
99
Transducer is placed on the skin with intervening gel. Fingers are on the side of the transducer to guide the transducer while scanning.
ultrasound
100
Ultrasound relies on the attenuation of the different tissue:
absorption, reflection, refraction, scatter