Chapter 7: Flashcards
Positive electrode
Anode
a.k.a positive beam limitation (PBL)
• to collimate automatically the x-ray beam to the same size as the image receptor
• prevents unnecessary exposure
Automatic collimation
Effect of motion
Blur
a.k.a Potter-bucky diaphragm
• moving grid used to remove scatter rad.
• can cause fog on the ir
Bucky
- light proof
- holding the ir
- imaging plage for CR or x-ray and intensifying screens
Cassette
Negative electorde
Cathode
- box-like structure
* containing lead shutters that limit thr x-ray beam to a specific area of the body
Collimator
Digital radiographic imaging using a cassette containing an imaging plate
Computed radiography
- Differences in densities
* Allows detail to be seen
Contrast
Video monitor
CRT cathode ray tube
Opaqueness/blackening
Density
used for bleding a picture archiving & communications system & various imaging modalities
DICOM Digital Imaging & Communication is Medicine
uses fixed detectors that directly communicate with a comp.
Direct digital radiography, DR
Misrepresentation of the SIZE & SHAPE
Distortion
s-number or exposure index that describes the status of the exposure and diagnostic value of the digital image
Exposure indicator
Film before exposure to Rad
Film
Area of the anode
• w/c x-rays emanate
Focal spot
- placed bet. the patient & the image receptor
* absorbs scatter rad
Grid
• graphic display - pixel values
Histogram
Captures the remnant beam
Image receptor
- made of PSP that absorbs the photon energies
* Located inside a computed radiographic cassette
Image plate
Converts an image information into NUMERICAL DATA
ADC
- mounted in the cassette singly or in pairs
* screens glow with visible light when struck by rad.
Intensifying screens
- wavelength of the x-ray beam
- ability to penetrate the body
- contrast of the rad. image
kVp
