Week One: Radiography Flashcards
What are the KEYS in a technicians’ role in imaging?
Consistent exposure and processing standards and a repetitive workflow
What is an X-Ray?
A short wavelength portion of the EM spectrum having an ability to penetrate/pass through biological tissue
How is an X-ray created?
By a machine that converts electricity into the EMR, hits and emerges from a target and is then recorded as an image on a capture device
What is a focal spot?
May be a L or S (select one of two cathode filaments in selected larger machines)
What is the effective focal spot size?
A reflection from anode’s surface
What is mAs?
Milliamperage at filament X exposure time
Controls the electron ‘boil’ from cathode and the quantity of X rays emanating off of the anode
What is Kvp?
The thousands of volts applied to ‘drive’ electrons from cathode to anode (Changes the EMR wavelength of the x-rays to affects the penetrant quality of the x-rays
What is the film-focal distance usually set to?
40’
FFD- The closer you get the _____ the x-rays and the further you get the _____ the x-rays
Stronger, weaker
What does collimate mean?
Accurately allign
At departure from the tube head the irradiation is filtered through a thin sheet of…
Aluminum
Removes/absorbs ‘softer’ irradiation to ‘harder’ beam
Order these into which lets more x-rays through to which ones stop more x-rays
water-filled, air, lead, water-containing,bone
Air, water-containing, water-filled, bone, lead
Latent image becomes a real image when the film is…
Processed
What is a latent image?
Potential image, not yet formed
What is True DR?
True digital radiography
Pixel sized sensor arrays detect the intensity and frequency of the transmitted x-rays
What is CR?
Computerized radiography
Not a direct process but results in a digitized image
Special cassettes with a storage phosphor that captures the latenet image
Describe the A&Pof a cassette
Front is radiolucent, intensifying screens, support/phosphor layers are part of the intensifying screens, emulsion layers contain granules of silver halloid
What does a ‘cloud’ look like on a film?
Dense black, no image
Where does developer solution work best (pH)
Alkaline
What are the steps of processing a film?
Develop: Put image into developer (forms a reaction between silver particles and developer solution)
Stop: Removes developer from emulsions
Fix: Dissolves particles that weren’t used leaving an actual image
Wash and dry: Use tap water to wash off
What does fresh developer look like? What does old developer look like?
(Dr. Crane’s words)
Fresh: Lemonade
Old: Iced tea
What is the anode heel effect?
Thicker side of the anatomy points toward the cathode (-), (CAVT’s cathode is on left side so ‘head left’), important in deep chested dogs
What does x-ray scatter do to a film?
Creates film ‘fog’, reduces contrast, degrades sharp edge effects
