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
Lead absorbs most of the SR that strikes the apron
Lead apron
Product of milliamperage & time
Current
mAs
Made up of rowns and columns of data
Matrix
Smallest component of matrix
Pixel - picture element
Automatically develops x-ray film
Processor machine
Viewed after it has been exposed and processed
Radiograph
Specific position
Radiographic positio
As if the body is in the anatomic position
Radiographic projectio
How rhe inage receptor sees the body image // the opposite of the rad. projection
Radiographic view
Sharpness of structural lines
Recorded detail
