Worksheet 3 Flashcards
Explain why it is important to a technician to understand the difference between radiolucent and radiopaque?
You can block the radiation or x-rays from creating an image on the receiving receptor.
If you use a radiopaque positioning you may be covering the area of interest.
Radiolucent allows x-rays to pass through.
Explain the word “artifact” when talking about radiology and give 2 examples seen in veterinary medicine?
It is an unwanted “image” on your film- can ruin or block your images. Not meant to be there.
Examples are: blur, fog, fog, fog, collars, name tags, static electricity, motion, human body parts etc
What are the 4 exposure factors we use in taking a radiograph?
kV (kilovoltage)
mA (millamperes)
mAs (milliampere seconds)
Distance
Exposure factor:
penetration of tissue, speed that the electrons are going from the cathode to the anode
kV (kilovoltage)
Exposure factor:
controls the amount of electrons that are being produced, how hot is the filament getting? The more heat, the more elections
mA (milliamperes)
Exposure factor:
the time factor, how long are x-rays allowed to leave the rube - aka the exposure time.
mAs (milliampere seconds)
Exposure factor:
how much distance is between the tube and the film/grid
Distance
Out of the 4 exposure factors- which one effects the penetrating power?
kV
what does kVp mean
kilovoltage peak - meaning you are using the maximum energy available at that kV setting
What is Sante’s rule used to determine?
kVp needed for exposure
how do you figure kVp needed for exposure
(2 x thickness) + 40 = kVp
Use Sante’s rule in the following problem.
An 80# dog needs thoracic radiographs. His lateral chest measures 20cm when you measure with calipers.
(2 x 20 cm) + 40 = 80 kVp
Pertaining to mAs:
The more _________ and longer the period of _______, the more _______ are produced
electrons
time
x-rays
how is mAs calculated
mA x seconds = mAs
What does SID stand for?
Source imagining distance, the distance between the tube and the image receptor (film/grid)
