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Week 2: Radiographic Equipment
1
Game PlanIdentify generic components of the radiographic equipment
Describe various planes of x-ray tube and table movement
Discuss contrast and density Exposure Factors
2
Generic Components of Radiographic SystemX-ray Tube
Collimator Assembly
Radiographic Table
Control Console
Tube support
3
4
Radiographic Room
X-ray Tube Housing
5
6
X-RAY Tube Housing
1. Lead and steel
2. Absorbs ______ radiation
3. Prevents x-ray photons from leaking from tube
7
X-RAY Tube
1. Made with Pyrex glass1. ____________
2. Gas Evacuated1. ____________
8
Early X-RAY Tube
9
The X-RAY Tube
1. ____ and ______ housing
2. _______ ______encased in a housing
3. Primary components
1. ___________ (+)2. &3. ___________ (-)
10
X-RAY Tube
1)
2)
11
X-Ray Machine
• Purpose:1. provide a specific current (mA) & voltage
(kVp) to the x-ray tube
1. _____ controls the energy of the x-ray photons
2. _____ controls the number of x-ray photons
2. convert electrical energy to electromagnetic energy (x- ray photons)
TO PRODUCE X-RAYS YOU NEED
A SOURCE OF ELECTRONS
A FORCE TO MOVE THEM QUICKLY
SOMETHING TO STOP THEM SUDDENLY
12
Source of Electrons
14
Cathode
1. Filament1. ________
________
2. Focusing cup (beam focus)
15
Process of x-ray production on Cathode side (-)
1. mA (milliamperage) is sent to filament
– Via cables
2. ____________ heats up – electrons “boil off”
(thermionic emission)
– focusing cup focuses electron beam toward anode
3. Electrons have ________ charge
A force to move them quickly.Something to stop them suddenly
17
Process of x-ray production on Anode side (+)
1. Positive voltage (kVp) is applied
2. Causes electrons to _________ towards anode
– Laws of attraction
3. Electrons “slam into” target of anode – suddenly stopped.
4. _________ ___________ARE CREATED
18
• High voltage to anode attracts electrons from cathode
• Current to stator causes rotation of anode
19
Anodes - Target
Cu
W
1. Common target (focal track)material is __________
Molybdenum or Graphite base
Rotating Anodes• 2” to 5” disk (focal track)
Rotation speeds Low: 3,000 – 3,600 rpm High: 9,000 – 10,000 rpm
20
X-ray Tube Anode
Stator and rotor make up the induction motor
Molybdenum stem connects rotor with anode reduces heat transfer to
rotor and bearings
Focal track area (spreads heat out over larger area than stationary anode configuration)
21
Rotating Anode
Molybdenum stem and base usedbecause it is a poor heat conductor
Tungsten can withstand high heat loads
22
How Are X-rays Made?
1. Source of
_______move at ______ speed (KE)
2. Collide with target or focal track on anode
3. KE of electrons converted to x rays & heat
1. 99% _______
2. 1% __________
Collimator Knobs
23
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Collimator
• Attaches directly below the x-ray tube
• Serves as a beam limiting device
• Controls ______ and ____ of the x-ray field
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Collimator Knobs
27
Cone collimator
28
Radiographic Table
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Tables• Tilting tables – diagnostic and
fluoroscopic work– 90 degrees in one
direction – 15 – 30 degrees in
the other direction– ancillary
equipment:• footboard,
shoulder support, handgrips, compression bands
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http://www.youtube.com/user/ARCOMAMED?blend=1&ob=5#p/a/u/2/C9fTjmQrfj8
35
TABLE OR UPRIGHT BUCKY TRAY
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The ‘bucky’ is like a drawer
37
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Image Receptors and Bucky tray
Film
Image ReceptorsCassette Based
1) Film /screen (FS)
2) Computed Radiography (CR)
Cassette-less
1)Digital Radiography (DR)
Indirect CaptureDirect Capture
39
Film Screen
40
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Darkroom for Film Screen Image receptors
42
What is in the Darkroom?
43
44
Safe Light1. __-__ Watts
2. _____ filter
3. Must be __-__ feet from counter top or feed tray of processor
4. Used to be amber or orange filter
45
FILM SCREEN PROCESSOR
46
CR- PSP plate
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CR Reader for Computed Radiography image receptors
Multiloader
49
Digital Radiography: Direct Capture
Amorphous selenium
50
Digital Radiography: Indirect Capture
Amorphous silicon
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52
• The bucky tray can be found:– In the table
or chest board
• Holds the cassettes– CR– Film
Screen
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55Bucky tray
56
Bucky Tray
Image receptor is held in bucky
57
FLUOROSCOPY: Images in motion
58
REMOTE ROOM
Conventional Room
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FLUOROSCOPYmust wear shielding
while x-ray beam is on
Lead apron Lead Curtain
Tube SupportsDesigned to help technologists with various
tube locations for creative imaging.
Tube suspension systems are available in 5 versions
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Floor mounted & Overhead Suspension
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Floor to Wall or Ceiling
65
Table Suspension
Telescoping Tube
66
Tube Movement
• Longitudinal
• Transverse
• Vertical
• Angling or Rolling
• Rotating
• Telescoping
CONTROL CONSOLEGives the
technologist control of the xray machine
Technique selection
Located OUTSIDE of the Radiographic Room
67
68
kVp & mAs
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The Control Console
1. Set technical factors 1. ________2. ________
2. Make an exposure
3. Only a legally licensed individual is authorized to energize the console
71
“Technique”kVp , mAs (mA x s)
• What is set at the control panel
• How the “image” is created on the “film” or Image receptor (digital)
• kVp controls the “ENERGY” of the beam
• The Higher kVp – more penetrating
• Ranges is 50 -110 in Diagnostic x-ray
72
“Technique”kVp , mAs (mA x s)
• mA- is the current in combination with the time – determines HOW LONG the beam will stay on
• Controls the density on the film/image
73
Ancillary EquipmentGrids
View boxes and viewing computers
Darkroom
Processors and Readers
Misc Equipment
74
Grids1. Body parts
___cm & more
2. Lead strips parallel to centerline
3. Absorbs _______– Improves
detail
75
76
1. Scatter adds a _____appearance
2. Makes image more ________
77
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Other x-ray equipment
• Positioning phantoms • Pixie
81
Other x-ray equipement• Positioning sponges• Lead markers
82
Positioning sponges
83
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Lead Shields
Gonad shields
Lead wrap arounds
Lead aprons
Lead Gloves and Glasses
85
Are x-ray machines prisoner to one room???
86
87
Mobile X-RAY equipment
1. __________– Take machine
to patient– Still images
2. __________– Used in
interventional procedures
– Used in surgery– Dynamic
images
88
PORTABLE UNITS
89
Trauma wrist done portable- using positioning devices
Lead apron
sponge
TAPE
90
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When patients cannot go the Radiology Department
92
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94
95
96
Review
98
X-ray Tube Construction
GF
ED
C
A
B
99
X-ray Tube Construction
A.
B.
C.
D.
E.
F.
G.
100
TUBE HOUSING
What is it made of?
101
TUBE HOUSING
________________
102
Is this rotating or stationary anode?
103
_______________________
What is required to produce x-rays?
105
What is required to produce x-rays?
Requirements:
____________________________________________
____________________________________________
____________________________________________
• ____________
• ____________