Chapter 3 - 1 Flashcards
(35 cards)
- The device that receives the radiation leaving the patient is the:
a. central ray
b. differential absorption
c. image receptor
d. compensating filtration
Solution: c. image receptor
X-ray photons must pass through tissue and interact with an image receptor, a device that receives the radiation leaving the patient.
REF: p.43
- _____ results in the process of image formation, whereby the x-ray beam interacts with the anatomic tissue, and a portion of the beam passes through the part and strikes the image receptor.
a. Transference
b. Differential absorption
c. Molecular modeling
d. Compensating filtration
Solution: b. Differential absorption
The radiographic image is formed as a result of differential absorption; some of the x-ray beam is absorbed in tissue, and some is transmitted. This variation in beam exiting the part will represent the area being imaged.
REF: p.43
- _____ is the loss of some of the energy from the x-ray beam as it passes through the tissue being imaged.
a. Compensating filtration
b. Attenuation
c. Photon transmission
d. Photoelectric scattering
Solution: b. Attenuation
Attenuation is the loss of energy from the x-ray beam as it passes through tissue, due to interactions between the x-ray photons and the tissue.
REF: p.43
- The photoelectric effect involves the removal (ejection) of an electron. This process of removing an electron from an atom is known as:
a. attenuation
b. transmission
c. ionization
d. differential absorption
Solution: c. ionization
- When the x-ray photon travels completely through the part, that activity is called:
a. acceleration
b. attenuation
c. transmission
d. absorption
Solution: c. transmission
Transmission results when no interactions occur between the x-ray photon and tissue.
REF: p.49
- When the x-ray photon strikes an atom within the tissue being imaged and loses all of its energy to an inner shell electron of that atom, the photon is said to have been _____ and undergone the _____.
a. transmitted; Compton effect
b. absorbed; photoelectric interaction
c. attenuated; Compton effect
d. scattered; coherent interaction
Solution: b. absorbed; photoelectric interaction
During the photoelectric interaction, the incoming x-ray photon energy is absorbed, and an inner shell electron is ejected.
REF: p.44
- When the x-ray photon strikes an atom within the tissue being imaged and loses only part of its energy to an outer shell electron of that atom, the photon is said to have been _____ and undergone the _____.
a. transmitted; coherent effect
b. absorbed; photoelectric interaction
c. attenuated; photoelectric interaction
d. scattered; Compton interaction
Solution: d. scattered; Compton interaction
The Compton interaction involves the x-ray photon ejecting an outer shell electron, giving up some of its energy, and changing its path.
REF: p.45
- The interaction between x-ray photons and tissue that results in production of a secondary x-ray photon is the:
a. coherent interaction
b. Compton interaction
c. photoelectric interaction
d. characteristic interaction
Solution: c. photoelectric interaction
After the inner shell electron is ejected during the photoelectric interaction, the hole that is left is filled by upper level shell electrons, resulting in excess energy that results in a secondary photon.
REF: p.45
- When the entering x-ray photon loses energy and changes its path of travel as a result of interacting with an atom, the interaction is known as the:
a. compensating effect
b. photoelectric interaction
c. characteristic effect
d. Compton effect
Solution: d. Compton effect
The Compton effect involves the entering x-ray photon losing energy (as a result of ejecting an outer shell electron) and changing direction.
REF: p.45
- The probability of total photon absorption by the photoelectric effect depends on the:
a. energy of the incoming x-ray photon
b. energy of the ejected electron
c. atomic number of the anatomic tissue
d. A and C
e. B and C
Solution: d. A and C
The probability of total photon absorption by the photoelectric effect depends on the energy of the incoming x-ray photon and atomic number of the anatomic tissue.
REF: p.44
- The outer shell electron that is ejected during the Compton interaction is also known as a:
a. photoelectron
b. secondary electron
c. Compton electron
d. B and C
Solution: d. B and C
The electron that is ejected during the Compton interaction between an x-ray photon and an atom is also called a secondary or Compton electron.
REF: p.45
- The x-ray photon that is scattered as a result of the Compton effect cannot:
a. be absorbed in the tissue, resulting in additional patient exposure.
b. strike the image receptor and provide useful anatomic information.
c. strike the image receptor without providing useful information.
d. exit the patient, exposing persons near the patient.
Solution: b. strike the image receptor and provide useful anatomic information
The scattered photon can strike the image receptor, but it will not provide any useful anatomic information.
REF: p.45
- Interactions of high-energy X-rays (energies beyond the diagnostic range) with tissue include:
a. pair production
b. coherent scattering
c. photodisintegration
d. A and B
e. A and C
Solution: e. A and C
Both pair production and photodisintegration are interactions between X-rays and tissue that involve x-ray photons with energies higher than the diagnostic range.
REF: p.46
- Interactions of low-energy X-rays (energies below the diagnostic range) with tissue include:
a. pair production
b. coherent scattering
c. photodisintegration
d. A and B
e. A and C
Solution: b. coherent scattering
Coherent scattering occurs with very-low-energy X-rays and results in the incoming x-ray photon changing direction with no loss of energy.
REF: p.46
- The x-ray beam that leaves the patient in the direction of the image receptor is often referred to as:
a. primary radiation
b. remnant radiation
c. absorbed radiation
d. scattered radiation
Solution: b. remnant radiation
Remnant radiation, which consists of both transmitted and scatter radiation, exits the patient in the direction of the image receptor.
REF: p.49
- If scattered photons are absorbed within the anatomic tissue, they:
a. contribute to the radiation exposure of the patient.
b. do not contribute any useful information about the anatomic part of interest.
c. contribute useful information about the anatomic part of interest.
d. A and B
e. A and C
Solution: d. A and B
If a scattered photon strikes the image receptor, it will not provide any useful anatomic information and will increase the radiation exposure to the patient.
REF: p.46
- The amount of x-ray beam attenuation is affected by the:
a. thickness of the body part
b. atomic number of the atoms in the tissue
c. tissue density
d. energy of the x-ray beam
e. A and B only
f. all of the above
Solution: f. all of the above
The amount of x-ray beam attenuation is affected by the thickness of the anatomic part, the atomic number of the atoms contained within it, its tissue density, and the energy of the x-ray beam.
REF: p.47
- An increased part thickness results in:
a. increased beam attenuation
b. decreased beam attenuation
c. no effect on beam attenuation
Solution: a. increased beam attenuation
Increasing the thickness of a given anatomic tissue increases beam attenuation by either absorption or scattering.
REF: p.47
- A body tissue with an increased tissue density results in:
a. increased beam attenuation
b. decreased beam attenuation
c. no effect on beam attenuation
Solution: a. increased beam attenuation
Increasing the tissue density increases beam attenuation by either absorption or scattering.
REF: p.48
- Unwanted exposure to the IR due to scatter radiation is called:
a. latent
b. manifest
c. fog
d. cloudiness
Solution: c. fog
Fog is the result of scattered photons interacting with the image receptor; it is additional exposure without any useful information.
REF: p.50
- The ______ image occurs first on the image receptor, and the ______ image occurs following proper image development/processing.
a. manifest, latent
b. invisible, latent
c. visible, manifest
d. latent, manifest
Solution: d. latent, manifest
The latent (or invisible) image occurs first, and after processing, the manifest (visible) image appears.
REF: p.51
- At higher kilovoltage, ______ photon interactions occur, resulting in ______ transmission.
a. more, increased
b. more, less
c. fewer, increased
d. fewer, less
Solution: c. fewer, increased
At higher kilovoltage (energy), fewer photon interactions occur, resulting in more x-ray photons being transmitted.
REF: p.47
- Beam attenuation __________ with a higher-energy x-ray beam.
a. increases
b. decreases
c. stays the same
Solution: b. decreases
Beam attenuation decreases with a higher-energy x-ray beam and increases with a lower-energy x-ray beam.
REF: p.49
- Brightness/density is a quality related to the ______ of the radiographic image.
a. visibility of structures
b. accuracy of structural lines
c. spatial resolution
d. B and C
Solution: a. visibility of structures
Brightness/density is a quality related to the visibility of anatomic structures of the radiographic image.
REF: p.52