1. CHAPTER 3 EQUIPMENT OPERATION AND QUALITY CONTROL
EXAMINATION REVIEW FOR RADIOGRAPHY

2. ARRT Certification Exam: Equipment Operation and Quality Control
Twenty-two questions (11% of the examination)
Three primary sections
Principles of Radiation Physics
Imaging Equipment
Quality Control of Imaging Equipment and Accessories

3. Principles of Radiation Physics: X-ray Production
Primary requirements
Source of free electrons
Cathode (− charge)
Heated filament
Focusing of electrons
Focusing cup
Acceleration of electrons
Applied kVp
Deceleration of electrons
Rotating tungsten anode (+ charge)

4. Principles of Radiation Physics: X-ray Production—(cont.)
The x-ray tube produces x-rays due to the conversion of high-speed electrons (kinetic energy) into electromagnetic energy (x-ray photons, heat, and light).
X-ray tube efficiency: 1% x-ray production
99% of energy produced: heat
Two primary atomic interactions occur in the x-ray tube
Bremsstrahlung (85% of radiation produced)
Characteristic (15% of radiation produced)

5. Bremsstrahlung Radiation
Projectile electron loses kinetic energy (KE) as it interacts with the nuclear field of a target atom.
Deceleration occurs due to a change in direction of the projectile electron.
Lost KE converted to x-ray photons
Produces varying energy levels and wavelengths of x-ray photons

6. Characteristic Radiation
Projectile electron ionizes a k-shell electron of a target atom.
Opening in K-orbit replaced by an outer shell electron (transition)
Characteristic radiation photon released
Produces fixed energy x-ray photons
In a tungsten target, no characteristic radiation will be produced under 69 kVp.

7. Fundamental Properties of Electromagnetic Radiation and X-ray Photons
Descriptive or controlling factors
Frequency
Wavelength
Velocity
Energy
Inverse square law

8. Characteristics of the X-ray Beam
Descriptive or controlling factors
Quality
Voltage
Quantity
Current
Filtration
Target material
Voltage waveforms/generators

9. Primary versus Remnant (Exit) Radiation
Primary radiation
Primary beam
Leakage radiation
Remnant or exit radiation

10. Imaging Equipment: Operating Console
Power: (on/off)
kVp control
Provides E for beam penetration
mA control
Controls quantity or intensity of x-ray beam
Timer
Used in conjunction with mA to control the intensity of x-ray beam

11. Imaging Equipment: Automatic Exposure Control
Components
Ion chambers or sensors
Density controls
−2 to +2
Backup timer

12. Imaging Equipment: Circuit Components
X-ray tube
Produces x-rays
Transformers
Controls and varies voltage
Incoming current: 60 Hertz AC
Each peak = one pulse
Rectifers
Converts AC to DC
Generators
Single phase
Three phase

13. Imaging Equipment: Accessory Devices
Beam restriction devices
Adjustable collimator
Aperture diaphragm
Cones and cylinders
Grids
Stationary
Reciprocating (Bucky device)

14. Dedicated X-ray Equipment
Chest:
freestanding system for upright imaging
Often incorporates
Automatic vertical tracking
Automatic collimation
Tomography: focuses on a single plane
Tube and IR move synchronously around a fulcrum

15. Fluoroscopic Equipment
Used for real-time imaging
Conventional and digital systems available
Fixed or mobile (C- arm) systems
Components
X-ray tube
Image intensifier
Automatic brightness control
Display screen/monitor
Recording device(s)

16. Digital Imaging Filmless equipment Two types Computed radiography (CR)
Digital radiography (DR)

17. Digital Imaging: Computed Radiography (CR)
Components and image acquisition
Reusable imaging plate
Photostimulable phosphor (PSP)
Stores latent image
Laser reader
Stimulates phosphor to release light photons
Monitor
Displays image
Fluorescent light
Erases PSP

18. Digital Imaging: Digital Radiography (DR)
Components and image acquisition (two types)
Direct panel DR (amorphous selenium)
Converts x-ray photons directly to an electric signal, sent to a computer
Indirect panel DR (amorphous silicon)
Converts x-ray photons to light to an electric signal, sent to a computer

19. Quality Control (QC) of Equipment and Accessory Devices
Beam restriction devices QC tests
X-ray/light field alignment: ±2% of SID
Central ray alignment
Shielding QC tests (aprons, gloves, and gonadal shields)
Visual inspection for tears or cracks
Fluoroscopy check for holes or cracks

20. Digital Imaging Quality Control: Artifacts
Types/causes
Debris/dust
Scratches
Incomplete erasure
Ghost images
Fog
Software

21. Digital Imaging: Monitor Quality Control
Checked monthly or quarterly
SMPTE (Society of Motion Picture and Television Engineers) test pattern
Tests monitor for
Sharpness
Distortion
Luminance