SOD THEORY 2 UPDATED ACTUAL EXAM
QUESTIONS AND CORRECT ANSWERS
●● What do the histogram and look up table do?
Answer: Histogram assesses the range and quantity of IR exposures.
(Arranges pixel values)
The LUT applies a standard contrast for the selected exam to give the
desired image contrast.
●● Describe what happens during the photoelectric effect
Answer: Incoming xray photon collides with an inner shell electron and
ejects it. That electron becomes a photo electron. The xray is completely
absorbed. One of the outer shell electrons cascades down to fill the
empty space. As it drops into that space, it may give off excess energy as
a secondary photon.
●● Which interaction (Compton or photoelectric) is responsible for
contrast produced on the radiographic image?
Answer: Photoelectric
●● The absorption of primary X-rays during the photoelectric
interaction depend on what 2 factors?
Answer: The Atomic number of the atoms that the xray is interacting
with and the energy of the xray
, ●● The likelihood of photoelectric interactions _____________
(increases or decreases?) when atomic number of atoms increases?
Answer: Increases
●● As the energy (kVp) increases, does photoelectric interactions
increases or decrease? Why?
Answer: Decrease
B/c the xray beam will have more energy to pass through the tissues and
transmit onto the IR.
●● What are the 2 factors that allow detail to be seen?
Answer: IR exposure and contrast
●● What is image contrast?
Answer: The differences between adjacent grays
(The difference between adjacent IR exposure levels - idk this is what
the book said)
●● What is dynamic range?
Answer: The range of brightnesses as displayed on the monitor
QUESTIONS AND CORRECT ANSWERS
●● What do the histogram and look up table do?
Answer: Histogram assesses the range and quantity of IR exposures.
(Arranges pixel values)
The LUT applies a standard contrast for the selected exam to give the
desired image contrast.
●● Describe what happens during the photoelectric effect
Answer: Incoming xray photon collides with an inner shell electron and
ejects it. That electron becomes a photo electron. The xray is completely
absorbed. One of the outer shell electrons cascades down to fill the
empty space. As it drops into that space, it may give off excess energy as
a secondary photon.
●● Which interaction (Compton or photoelectric) is responsible for
contrast produced on the radiographic image?
Answer: Photoelectric
●● The absorption of primary X-rays during the photoelectric
interaction depend on what 2 factors?
Answer: The Atomic number of the atoms that the xray is interacting
with and the energy of the xray
, ●● The likelihood of photoelectric interactions _____________
(increases or decreases?) when atomic number of atoms increases?
Answer: Increases
●● As the energy (kVp) increases, does photoelectric interactions
increases or decrease? Why?
Answer: Decrease
B/c the xray beam will have more energy to pass through the tissues and
transmit onto the IR.
●● What are the 2 factors that allow detail to be seen?
Answer: IR exposure and contrast
●● What is image contrast?
Answer: The differences between adjacent grays
(The difference between adjacent IR exposure levels - idk this is what
the book said)
●● What is dynamic range?
Answer: The range of brightnesses as displayed on the monitor
