Overview of Radiographic Imaging Techniques
Technical competencies of the radiographer.
Milliampere second meter.
Rotor and exposure switch
Automated exposure controls
Selection of exposure factors
Proper care of radiographic equipment
Characteristics of x-radiation
Characteristics of x-ray photons
Imaging system: X-ray film
Contrast emulsion equals small, uniform grain size
Characteristics of x-ray film
o density maintenance (speed versus mAs)
o margin of errors in technical factors that the film allows that will still produce an acceptable range of densities
o inherent ability to record minute differences in densities across the film
Types of x-ray film One. screen-type film
▪ ways of reducing parallax effect
o advantages of screen-type film
o disadvantages of screen-type film
Two. direct-exposure film
Three. single-emulsion film
Types of film according to spectral sensitivity
Classification of films according to use
Two. therapy localization film
o extraoral film - screen-film
Personal Notes from Dean Abelardo L. Marva the Third's Research and Lectures
Nine. dosimeter or personnel monitoring film
o thermoluminescent dosimeter
o optically-stimulated luminescent dosimeter
Ten. automatic serial changer
Twelve. polaroid radiographic film
• Gurney-Mott theory - the only accepted theory in the explanation of photographic effect
Imaging system - intensifying screen
radiation dose, technical factors, one tube life
Layers of the intensifying screen
Selection of radiographic imaging system
Comparison of screen speed
Screen speed measurements
Processing the Radiograph
Factors to Consider in the Processing Room
Three. protects against radiation
Six. light-tight entrance
Darkroom and automatic processor quality control
Three. automatic processor temperature
o function of replenishment
Six. developer specific gravity
Seven. processor control chart monitoring
Quality Control test Schedule Standard
Developer specific gravity
daily Speed and contrast indicators should not vary more than plus or minus zero point fifteen optical density from baseline measurements
• processing system tanks
• ninety seconds automatic processor
• double capacity processor
• temperature control system
Factors affecting the washing rate
Factors affecting the drying process
Maintaining the processing unit
Cleaning and maintenance (recommended)
Processor and handling malfunctions and artifacts
Chemistry overview - Development
Factors that may affect the finished radiograph
Developer chemistry overview
Factors that affect the use of the fixer
Indicators of Inadequate Processing
Personal Notes from Dean Abelardo L. Marva the Third's Research and Lectures
Alternative processing methods
electrolytic recovery units
Technical Factors in Radiography
density maintenance (kVp and mAs)
quantum mottle or image noise.
SID or FFD - length of space from the focal spot to the recording medium.
Overview of Radiographic Quality
Characteristics of image quality (Bushong)
Tools for increasing radiographic quality (Bushong)
selection of exposure factors.
Photographic quality factor - Radiographic Density
Photographic quality factor - Radiographic Contrast
Contrast terminology higher contrast is lower contrast is
Factors Affecting Density
density maintenance (kVp and mAs)
• density maintenance formula
Factors affecting contrast
• IS speed is influenced by
Factors Affecting Distortion
Types of beam restriction
Beam alignment test for collimators
Control of Scatter Radiation - Grids and Air Gap
Stationary grids versus moving grids
Contrast improvement factor
Grid errors - focused grids.
Scatter Radiation, Filtration, and Patient Exposure.
Factors affecting scatter
Scatter radiation vs. contrast
Evaluation of radiographs - Characteristic curve
Nomenclature for characteristic curves
Logarithms in sensitometry
Constructing characteristic curves Bushong plus Burns
Relationship of density to light transmission
Critique of the Radiographic Image
o film handling artifacts
o darkroom and processing artifacts
o artifacts from the patient
Preparation of Radiographic Exposure Guides
Function of exposure guides
o types of technique charts
Standardization of exposure guides
Types of technique charts
Two. automated exposure guides
Three. Variable kilovoltage peak - fixed milliamperes per second charts
Four. Fixed kilovoltage peak (optimal kilovoltage peak) - variable milliamperes per second charts
Five. Variable technique (vary both milliamperes per second and kilovoltage peak)
Requirements for the preparation of exposure guides
Comparison of Exposure guides