Chapter 7 Interactions with Matter: Test Review

Which goal best describes why understanding x-ray photon interaction is emphasized in this chapter?

• To speed up imaging equipment maintenance

• To minimize patient harm and produce better quality images

• To reduce the cost of radiographic exams

• To increase the number of images taken per session

Which three x-ray interactions occur within the range of energy used in diagnostic radiography?

• Classical (coherent) scattering, Compton scattering, Photoelectric effect

• Compton scattering, Pair production, Photodisintegration

• Photoelectric effect, Pair production, Photodisintegration

• Classical (coherent) scattering, Pair production, Photodisintegration

Which pair of interactions are specifically highlighted for their effects on both image quality and patient dose?

• Classical scattering and pair production

• Photoelectric absorption and Compton scattering

• Compton scattering and photodisintegration

• Pair production and photodisintegration

Which term is another name for classical scattering in x-ray interactions?

• Photoelectric effect

• Compton scattering

• Coherent (Thomson) scattering

• Pair production

In classical (coherent) scattering, what happens when a low-energy incident x-ray photon interacts with an orbital electron of a tissue atom?

• The photon is completely absorbed, ejecting the electron from the atom

• The photon transfers energy, the atom becomes excited, and the photon is released in a new direction

• The photon increases in energy and continues in the same direction

• The photon creates an electron-positron pair

What is a direct consequence of a photon undergoing classical scattering for patient safety considerations?

• It reduces image scatter and lowers dose

• It becomes a scatter photon that adds to patient dose

• It is converted entirely into heat with no dose impact

• It produces secondary radiation that exits the patient without interaction

A technologist needs to minimize contributions to patient dose from low-energy interactions. Which adjustment best reduces the likelihood of classical scattering events?

• Use lower kVp to increase the number of low-energy photons

• Increase beam filtration to remove low-energy photons

• Increase mAs to produce more photons overall

• Use a grid to absorb high-energy primary photons

Which statement best describes the initial event in a photoelectric interaction?

• An x-ray photon scatters from an outer-shell electron without energy loss

• An incident x-ray photon removes an inner-shell electron from a tissue atom

• A nucleus absorbs the x-ray photon and emits gamma radiation

• Two x-ray photons collide and annihilate

During a photoelectric interaction, what happens to the energy of the incident x-ray photon?

• It is partially absorbed and partially scattered

• It is converted entirely into heat in the detector

• It is totally absorbed in removing the inner-shell electron

• It remains unchanged as the photon passes through

What is the ejected electron produced by a photoelectric interaction called?

• Auger electron

• Compton electron

• Photoelectron

• Secondary proton