Exam 2 Flashcards
(91 cards)
1
Q
What is the defining characteristic of ultrasounds?
A
Benefit of real-time imaging
2
Q
A second benefit to ultrasound is the ability to do what?
A
Move the diagnostic probe in any direction
3
Q
What is not a factor in ultrasound?
A
Use of ionizing radiation
4
Q
The probe on an ultrasound is also known as the _____
A
Transducer
5
Q
Speed of sound varies with _____ of tissues
A
density
6
Q
What ultrasonic mode is associated with brightness?
A
B-Mode
7
Q
If pixels are bright they are ________
A
Hyperechoic
8
Q
If pixels are dark they are ______
A
Hypoechoic
9
Q
What ultrasonic mode is associated with motion?
A
M-Mode
10
Q
__-mode creates __-mode
A
M-mode creates B-mode
11
Q
Shows the image of the flow of blood and other liquids
A
Doppler
12
Q
In color flow Doppler imaging, the information collected is presented as a color overlay on top of a __-___ image
A
B-image
13
Q
In the color flow Doppler, blue moves ____ the probe and red moves ____ the probe
A
Blue moves away from the probe, and red moves toward the probe
14
Q
Change shape with eletrical current
A
Piezoelectric ceramics
15
Q
_______ in ceramics emit a mechanical vibration at a preset frequency
A
Crystals
16
Q
Sound frequency emitted is usually set anywhere between __ and ____ megahertz (MHz)
A
2 and 18
17
Q
What is the sound frequency set for opthalmic studies?
A
Up to 50 MHz
18
Q
Sound waves do not travel through ___
A
Air
19
Q
What is digitized to create a diagnostic image?
A
Electrical current
20
Q
There is an inverse relationship between increasing the ______ output and the maximum ____ it can scan
A
frequency, depth
21
Q
The higher the frequency the ______ it will penetrate
A
less
22
Q
The higher the frequency the ____ the lateral spatial resolution
A
higher
23
Q
Where is lateral spatial resolution best?
A
Near probe
24
Q
Transducer with flate contact surface and fine detail imaging
A
Linear transducer
25
Transducer used for general scanning, aka sector prober or curvilinear
Convex Transducer
26
Transducer similar to convex but smaller, used for small patients and intercostal studies
Microconvex transducer
27
Transducer that creates 3D images
Matrix transducer
28
Transducer containing piezoelectric elements that are stimulated in complex timing sequences, steered through firing time delays. Most used for cardiac studies.
Phased Array Sector Transducer
29
What are ultrasounds used for in bovine/ruminants?
Reproductive and biopsies
30
What are ultra sounds used for in equine?
Tendon and ligament injuries and fertility
31
What are ultrasounds used for in porcine?
Back fat levels
32
Artifacts that are created by air pockets, metallic objets, foreign body
Comet tails
33
Artifact caused by redirection of sound, associated with curved fluid-filled structures such as the gall bladder, urinary bladder, cysts and sometimes kidneys
Edge shadowing
34
This artifact occurs when the sound beam travels through weakly attenuating structures such as as bladder with fluid
Acoustic enhancement
35
In acoustic enhancement artifacts, the reflection appears brighter at the ___ side of the structure
Far side
36
Artifact that occurs when sound beam reflects back from the surface between two structures and the machine misinterprets it and places a mirror image on one of the structures
Mirror image
37
Artifact resembling the northern lights, caused by repeated reflection of echoes trapped between two strong reflectors (ie. gas filled loop of bowel)
Reverberation
38
Artifact that occurs when sound beam hits a dense object (such as a bladder stone), sound beams are reflected away and are absorbed creating dark streak or shadow
Acoustic shadowing
39
Use the magnetic field and radio frequencies to determine the chemical makeup of a substance
MRI (Magnetic Resonance Imaging)
40
Shows concentration of free-floating hydrogen molecules in tissue, much better contrast than CT
MRI
41
MRI's are superior in demonstrating what structures?
Brain, spinal cord, and soft tissue structures (ligaments and cartilage)
42
MRI's _____ (do or don't) use ionzing radiation
Do not
43
Molecules in an MRI align based on their _____ and become magnitized
polarity
44
MRI's are tuned to the frequency of what?
Hydrogen atoms in molecules
45
Magnet with two slabs facing each other, with lower field strengths
Permanent magnet
46
Low field magnets with electrical charge through copper wiring wrapped around a center
Electromagnets (resistive magnets)
47
Most common magnet, superconductive in very low temperatures. Massive electromagnet.
Superconducting magnets
48
Nuclear medicine is divided into what two groups?
Therapeutic and diagnostic
49
Administration of radioactive iodine for the treatment of hyperthyroidism and thyroid tumors
Veterinary therapeutic nuclear medicine
50
Administration of radionucleotides to the patient and detection of the electromagnetic radiation emitted from the patient via a gamma scintillating camera
Diagnostic nuclear medicine
51
In nuclear medicine _____ is attracted to bone
Technetium Tc 99m
52
In nuclear medicine ______ is attracted to the thyroid gland
Iodine I 131
53
What isotopes in nuclear medicine are used in horses?
Technetium Tc 99m
54
Half life of technetium 99m and protocol
6 hour half life, 24-48 hours protocol
55
Nuclear medicine waste products need to be kept in lead line container for \_\_-\_\_\_ hours
24-48
56
Minimum views required for pelvis and pelvic limbs
Two views
57
When radiographing pelvis/pelvic limbs, high ____ is preferred
contrast
58
When radiographing pelvis/pelvic limbs ____ \_\_ technique is preferred
Table Top
59
What routine views are used for pelvis?
Lateral, Ventrodorsal hip extended
60
What routine views are used for the femur?
Lateral, craniocaudal
61
What routine views are used for the stifle?
Lateral, caudocranial
62
What routine views are used for the tibia/fibula?
Lateral, caudocranial
63
What routine views are used for the foot (tarsus/metatarsus/digits)?
Lateral, plantardorsal
64
The main required view for pelvis radiograph (OFA)
VD hip extended for coxofemoral joint
65
What pelvis radiograph is needed to determine the laxity in coxofemoral joints
PennHIP
66
At what age can OFA's be submitted?
2 years or older
67
How are OFA's rated?
Excellent, good, fair, or poor
68
What must be included in an OFA view?
Pelvis bilaterally symmetrical
Patellas and stifle joints included
Last three lumbar vertebrae
Femurs parallel with equal ischial overlap
Patellas centered in femoral groove
69
What three views must be included for PennHIP?
Extended VD
Compression
Distraction
70
What do compression views measure?
the extent to which the femoral head fits within the acetabulum
71
What do distraction views measure?
the amount of passive laxity inherent in the joint
72
At what age can PennHIPs be taken?
16 weeks
73
What reasons do we send in PennHIP for?
Joint laxity
CHD (Canine hip displaysia) and oestoarthritis
DJD (Degenerative joint disease)
74
How many views are required for small animal forelimbs?
2
75
What limbs are routinely radiographed lateral and caudocranial?
Shoulder, scapula, humerus
76
What limbs are routinely radiographed lateral, and craniocaudal?
Elbow, radius, ulna
77
What two routine views are done for the foot?
lateral and dorsopalmar
78
What is measured for the lateral and craniocaudal scapula view?
cranial scapula border
79
Where is the central ray positioned for the shoulder joint?
Scapulohumeral articulation
80
What are the borders for the shoulder joint?
Proximal third of humerus and scapula
81
What are the borders for the scapula?
Shoulder joint and caudal border of the scapula
82
For the pelvis measurement, the caliper should be placed \_\_\_\_\_\_\_
Laterally
83
The caliper measurement is used to determine _____ for both lateral and VD pelvis radiograph
kVp
84
Where is the primary beam centered for a pelvis radiograph?
Centered over hip joints
85
For a pelvis lateral view, the lower leg should be pulled slightly \_\_\_\_\_\_\_
cranial
86
For a pelvis lateral view include entire \_\_\_\_\_\_, portion of the _____ \_\_\_\_\_ and most of the \_\_\_\_\_
Pelvis, lumbar spine, femur
87
What view should be used when pelvic trauma is suspected?
Frog leg view
88
In frog leg view, femur should be flexed at _____ degrees
45 degree angle
89
What pelvic view puts minimal stress on pelvis?
Frog leg view
90
Where should the beam be centered for a VD view of the pelvis?
Over level of pubis and acetabulum
91
Where should the measurement be taken for a VD view of the pelvis?
Over the acetabulum
