List reasons that cause mobile radiography to be extremely challenging?
Trying to achieve optimal image quality w/out stationary equipment.
Working w/less cooperative patients.
Requires special adaption of routine projections, imaginative equipment manipulation, and innovative technical factor considerations.
Work in high stress environments
List some steps you should take prior to x-raying a patient with mobile equipment?
Park unit outside initially
Obtain patients permission
Arrange room and equipment, taking extreme care
Do not be in a hurry
List some factors that should be considered regarding positioning and pathology when using mobile equipment?
Patients often unable assume standard positions but try to get them to.
Patients need to be semi-erect for CXR.
Need horizontal beam for air-fluid image.
Don't assume apparently "well" patients can be transported to stationary equipment.
Don't assume a poor quality image from mobile equipment.
Increased possibility of artifacts.
Nurse or physician must be consulted before moving any patient lines.
Who is responsible for ensuring radiation protection procedures are followed during a mobile exam?
What are the rules for radiation protection in mobile radiography?
What are two types of mobile radiography equipment?
Battery-driven, battery operated
Standard power source, non-motor driven
How are the two types of mobile radiography equipment propelled?
Battery-Driven-Self propelled by battery power
Non-Motor Driven-Pushed by the RT.
How are the battery powered units recharged?
Plug the units into a 110V (or a 220V Outlet). Normally, units are plugged into an outlet when not in use. If a unit becomes totally discharged it may take up to 8 hours to fully recharge it.
How do 110V standard power source mobile radiography units generate the higher voltage output needed for an acceptable radiograph?
110V units incorporate a capacitor discharge system to generate higher voltage output.
What safety features is required for self-propelled mobile radiography units?
Requires dead-man switch.
Discuss the kilovoltage technical factor of mobile radiography?
Mobile unit produce x-ray beam w/average photon energy different from stationary equipment. Full power 3-phase units produce very efficient no-ripple wave form. Capacitator discharge units have serious kV limitations as there is up to 30% drop in voltage during exposure.
Discuss the mAs technical factor of mobile radiography?
Lower power units may not be able to produce high mAs for grid radiography. May have to increase kVp to obtain optimal density. May result in motion problems due to increase exposure time.
Discuss the distance technical factors of mobile radiography?
A primary cause of repeats is failing to measure SID. There is a 15% margin of error to avoid density differences. Use 40" or 72" w/56" as a fall back.
Discuss the use of grids in mobile radiography?
Proper alignment difficult. Use low ratio, parallel grids to increase margin of error.
Discuss the use of film/screen combinations in mobile radiography?
Use wider latitude film/screen combinations that will have a slower speed, greater resolution, and lower contrast.