Chapter 15 Flashcards
Typical power source for recharging batteries
110-120 volts
Digital receptor with electrical cord
Tethered detector
Unpopular and nearly obsolete type of generator for mobile units
Capacitor discharge
Should be repositioned after consulting a nurse or physician
CVP line
Convenient SID for mobile radiopgraphy
56”
First to develop a portable unit
Picker corporation
Preferred radiopgrahic grid characteristics for mobile radiography
Low ratio and high frequency
X-ray beam quality with current-day portable units
High frequency output
The 8 safe radiation protection practice
- Protecting yourself and patient as well as health workers
- Request the public and anyone else around to leave the room in order t take exposure
- Announce X-ray
- Carry two lead aprons-
- never place hand or any other body part in th beam
- provide gonadal protection for patient
- Achieve maximum distance from patient 6’ radius
- Label and handle each cassette carefully to avoid repeats
Give example of the minimum and maximum exposure factors from a standard mobile X-ray unit
KV= 50-125 MAs= .4 - 200
Hand controls
Top left- saves the left monitor or image to disk during live or last image hold
Top right-selects regular fluoro & vascular fluoro
Bottom left-fluoro; road mapping
Bottom right-high level fluoro
Mechanical movements
Horizontal cross arm Wig wag Wertical lift L-arm rotation Flip flop Orbital rotation
Horizontal cross arm
Extends 8”
Wig wag
Moves side to side; range varies
Vertical lift
Two bottoms located on top of C arm max 18”
L-arm rotation
Rotates 180 degrees in either direction
Flip flop
Pivots 0-180 & 0-90 in opposite directions, increase versatility by inverting X-ray tube & image intensifier
Orbital rotation
115 degree rotation standard 90 degree of understanding & 25 degree over scan . Oblique projection
Magnification mode
Tri-mode image intensifier side 9” to 12”
9” field size 9,6 & 4 and 12” is 12,9,6
Pulse mode
Generates a preset # of X-ray pulses used in primarily as a dose reduction and reduce heat units
The more advanced, full-power mobile units use____ energy for a power supply
Battery
What should a technologist do if the sterile environment is violated during a surgical procedure?
Notify a member of the surgical team immediately
With current, state-of-the-art portable units,
The batteries provide for exposures and travel
All of the following features are essential to a mobile radiographic unit EXCEPT
A) expandable 6ft exposure cord
B) automatic exposure control with single field
C) dead-man type exposure switch
D)clear display of exposure factors
Automatic exposure control with single field
What is the single most effective means of radiation protection for the radiographer performing mobile exam?
6’ radius
Trauma patients require
Adaptation in positioning & care
Imobilization
Use on backboards,cervical collar
Major adaptation of ___ is required
CR angle & IR placement
Radiographic equipment
Rad bags, lead, Grids
Digital Imaging (CR & DR) provide
A wide exposure latitude less repeats
___key for trauma situations
Collimation and centering
Self propelled system has a travel speed of
2.5 to 3 mph
With what kind of incline
7 degree
Driving range of up to
10m/hr
__ that operate on two drive wheels
Dual drive motor
Forward and reverse
Maneuvering close corners
Dead mans control
Parking brakes are automatically engaged when the control levels are not in use
Plugged into ___ for recharging
110v
Full discharged units take up to _ recharging time
8hrs
Standard power source, capacitator-discharge,non-motor driven X-ray units, no battery power,
Lighter in weight & usually not motor driven
Operate on ___ power source
110 to 220v
Stores electrical charges when plugged in no thendischarges electrical energy across the X-ray tube during exposure
Capacitor discharge system
Both battery power and plug in electrical power for increase output
Dual power source
C-arm fluoro forms a C shape with
X-ray tube on the bottom and intensifiers or detector on the top
Monitor
Image processor or display
Two monitors are
TV monitor and control cart
The active monitor will display the lat radiograph image created until the fluoro is used and new image created
Last image hold
Maneuverability
C arm is attached to the base that can be raised, lowered or extended
Cephalaic or caudal angle and rotated 180 degrees
180 degree rotation is not recommended bc
It increases OID which lowers image resolution and highers exposure to eyes and head and neck area for surgeon or radiologist
Common surgical procedures
Chalangraphy, open or closed reduction of fractures and hip pinnings
Images are recorded in succession while contrast media is injected
Cine loop capability
Pulse mode
Used to create X-ray beam that pulsates at timed increments to reduce exposure
Snapshot or digital spot mode
Results in a higher quality
Subtraction mode
Takes out bone only shows blood vessels, technique image in which the initial image is recorded during continuous fluoro
Roadmapping
Geography studies
30 degree tilt will do what to dose?
Increase dose by 4
Lead apron
.5 mm
Entrance exposure rate to the patient is around
13 R/min
Boost can…
Boost exp rate for large patients
Before entering a surgical suite, who must be consulted? A)the unit receptionist B)the attending physician C)the surgical technician D)any of the above
B
Output from battery operated units is essentially A)single phase unrectified B)single phase fully rectified C)three phase,6 pulse D)high frequency
D
Mobile examinations are difficult to accomplish bc
A)mobile equipment exposure techniques are dependent upon hospital power
B)stationary equipment is more reliable
C)exam conditions can vary widely
C
During mobile radiography, it is the radiographer a responsibility to request that\_\_\_ leave the immediate area prior to exposure A)physicians B)family members C)health professionals D)all of the above
D
How should the CR be aligned for an AP projection of the chest?
Perpendicular to the long axis of the sternum
A self propelled, battery driven mobile X-ray unit will generally go up a maximum incline of
7 degrees
How many lead aprons should be carried to a mobile radiographic exam
2
The preferred method for demostrating air fluid levels during mobile radiography is to make sure that
A)SID is 60”
B)patient is sitting fully erect
C)x Ray beam is perpendicular to the receptor
D)b & C
D
Modern mobile radiographic units possess A) a flat pane detector for image review B) disposable, single use battery C) a cabinet for film cassette storage D) remote exposure controls
D
In surgery or in the emergency unit, which situation should be considered?
A)the stress of performing in a high tension environment.
B)limitations due to aseptic conditions
C)the presence of additional critical equipment
D)all of the above
D
Is used to create an X-ray beam that activates at timed increments to reduce exposure during c arm fluoro
Pulse mode
When it is determined that air fluid level demonstration is a priority,___ projection may be required for___>
A)one; air fluid levels
B)one; a normal projection of the chest
C) two; one AP and one lateral projection
D)two; air fluid levels and a normal projection of the chest
D
Batteries used in mobile radiographic machines A)are rechargeable B)provide power for mobility only C)recharge using 220-240 V AC power D)all of the above
A
Which type of grid would permit wide exposure and centering latitude and would therefore be preferred for mobile radiography?
6:1
Which one of the 3 cardinal rules of radiation protection is the most effective means of reducing exposure during mobile and surgical procedures?
A)time
B)shielding
C)distance
D)none of the above all are equally effective
C
For the mobile radiography;radiographic grids should have a A)high ratio and low frequency B)low ratio and low frequency C)cross hatched design D)low ratio and high frequency
D
During mobile radiography, the radiographer must achieve maximum distance primarily from the A)patient B)mobile patient C)IR D)X-ray tube
A
A common cause for repeat examinations in mobile radiography is due to A)equipment reliability B)angular ion of grids and grid cutoff C)inaccurate SID measurements D)low Image contrast
C
Proper tube grid alignment is important during\_\_radiography. A)mobile B)stationary C)portable D)all of the above
D
When taking a radiography during an ongoing surgical procedures the c arm mobile unit should be located:
A)same side of the surgical field
B)opposite site of the surgical fields
C)either of the above
B
During a mobile radiographic exam a radiographer will receive the lowest amount of patient scatter by standing two meters:
A)behind the patient
B)to the side of the patient
C)in front of the patient
B
