test prep Flashcards
Element
Smallest particle of a substance
Atoms
Smallest particle of an element
1Mostly empty space
2 Electrons circle nucleus in rings
Principle characteristic of “matter” (2)
Matter occupies space
Mass or weight
Energy’s principle characteristic (3)
Movement or motion
The ability to do work
Electromagnetic energy is used in radiography
Waves
Have height (amplitude) and frequency (wavelength)
Move at speed of light
Particles
X-rays – can be described as negatively charged electrons/particles
Photons
Smallest quantity of any type of electromagnetic radiation
Interact with matter as though particle
Specific energy dependent on frequency
Energy and frequency directly proportional
As energy increases, frequency increases
Radiation is
energy
X-ray – a form of
ionized radiation
X-ray travel in
straight line
Lateral radiographs the head is on the
left and the legs are on the ground
Principles of Protection
Time
Distance
Shielding
Components of an X-ray Unit
- High voltage transformer
- Operating console (generator)
- X-ray tube
Cathode
It is negatively charged and aimed at the anode
Anode
It has a positive charge
2 types of Anode
- Rotating
- Stationary
Anode Heel Effect
The intensity is greater on the cathode side.
If fluid or mass, may need to increase by kVp by
15 %
Barium advantages
- Inexpensive
- Excellent opacity and density
- Does not become diluted with secretions
Barium disadvantage
- Insoluble in body – if leaked may induce granulomas or adhesions
- Slow to transmit
- Blocks ultrasound waves
BIPS advantages
- Not likely to aspirate or to cause peritonitis
- Does not obscure abdominal detail
- easy to administer
BIPS disadvantages
- Expensive
- Cannot visualize mucosal detail or liminal margins
Ionic Iodine advantages
- Rapid transit
- Can be absorbed across mucosa and excreted by the kidneys
Ionic Iodine disadvantage
- Expensive
- Hypertonic which can cause fluid movement, peripheral vasodilation,
- Injectable irritating to the CNS and can cause irritation to some tissues
Nonionic Iodine advantages
- Rapid transit
- Fewer side effects because virtually isotonic with blood and CSF
3, Nonirritating
Nonionic Iodine disadvantage
Expensive
Negative Contrast
Air, nitrous oxide, oxygen and
Black on image
Barium Timing of Upper GI Dog
15 minutes
stomach and duodenum
Barium Timing of Upper GI – Cat
5 minutes
stomach, can be in duodenum
Barium Timing of Upper GI Dog
30 mins
some in stomach, most in duodenum and jejunum
Barium Timing of Upper GI Cat
15 minutes
some in stomach, most in duodenum and jejunum
Barium Timing of Upper GI – Dog
3-5 hours
small intestines empty
Barium Timing of Upper GI – Cat
2 hours
small intestine empty
