Podcast
Questions and Answers
What type(s) of radiation are being measured when a Geiger counter is used to measure a radioactive source with its cover removed?
What type(s) of radiation are being measured when a Geiger counter is used to measure a radioactive source with its cover removed?
What do radiation interactions in a gas-filled detector create?
What do radiation interactions in a gas-filled detector create?
Where do the negative electrons migrate to in a gas-filled detector?
Where do the negative electrons migrate to in a gas-filled detector?
According to the standard of practice, what should the percent energy resolution fall between for Cs137?
According to the standard of practice, what should the percent energy resolution fall between for Cs137?
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If the energy spread for Cs137 is 635 keV to 689 keV at half-maximum, does the instrument have an acceptable percent energy resolution?
If the energy spread for Cs137 is 635 keV to 689 keV at half-maximum, does the instrument have an acceptable percent energy resolution?
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Where is the region of operation on the voltage-response curve for a Geiger counter?
Where is the region of operation on the voltage-response curve for a Geiger counter?
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Does pulse mode operation of a gas-filled detector require a high photon flux to produce an accurate reading?
Does pulse mode operation of a gas-filled detector require a high photon flux to produce an accurate reading?
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What is the function of a collimator?
What is the function of a collimator?
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What is the most important factor in determining the appropriate matrix size for a digital image?
What is the most important factor in determining the appropriate matrix size for a digital image?
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Which of the following is the main difference between an all-purpose and a high-resolution collimator?
Which of the following is the main difference between an all-purpose and a high-resolution collimator?
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What is the function of a pulse height analyzer?
What is the function of a pulse height analyzer?
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Which of the following can be used as the stopping condition for a gamma camera image?
Which of the following can be used as the stopping condition for a gamma camera image?
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True or False: Septal penetration is more of a problem with higher-energy gamma rays than lower-energy gamma rays.
True or False: Septal penetration is more of a problem with higher-energy gamma rays than lower-energy gamma rays.
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What is the appropriate collimator if we want high-quality images of the bones of the hand?
What is the appropriate collimator if we want high-quality images of the bones of the hand?
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What is the function of a scintillation crystal?
What is the function of a scintillation crystal?
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What is the purpose of a photomultiplier tube in a scintillation detector?
What is the purpose of a photomultiplier tube in a scintillation detector?
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What is the minimum time separation required between two radiation events in order for them to be detected as two separate events?
What is the minimum time separation required between two radiation events in order for them to be detected as two separate events?
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Which type of collimator has better resolution at the same object-collimator distance?
Which type of collimator has better resolution at the same object-collimator distance?
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What mainly determines a gamma camera’s extrinsic resolution?
What mainly determines a gamma camera’s extrinsic resolution?
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Which of the following will improve image contrast?
Which of the following will improve image contrast?
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In filtered backprojection, how does the filter work in the reconstruction?
In filtered backprojection, how does the filter work in the reconstruction?
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In which SPECT study is it acceptable to acquire with a 180º orbit?
In which SPECT study is it acceptable to acquire with a 180º orbit?
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Which semiconductor material is used in commercial intraoperative probes?
Which semiconductor material is used in commercial intraoperative probes?
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What is the purpose of the photomultiplier tube in a scintillation detector?
What is the purpose of the photomultiplier tube in a scintillation detector?
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"Scintillators used for PET have different strengths. BGO has high stopping power for 511 keV photons and therefore maximizes the ________ detected." Fill in the blank.
"Scintillators used for PET have different strengths. BGO has high stopping power for 511 keV photons and therefore maximizes the ________ detected." Fill in the blank.
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"Scintillators used for PET have different strengths. LSO has a short decay time, reducing the number of ________." Fill in the blank.
"Scintillators used for PET have different strengths. LSO has a short decay time, reducing the number of ________." Fill in the blank.
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Select the correct incidence type:
Select the correct incidence type:
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In PET scans using CT corrections, is a single correction factor used for all tissues?
In PET scans using CT corrections, is a single correction factor used for all tissues?
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Is an area of increased activity on the non-attenuation-corrected PET scan always a real hot spot?
Is an area of increased activity on the non-attenuation-corrected PET scan always a real hot spot?
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What type of magnets are generally used in clinical MRI tomographs?
What type of magnets are generally used in clinical MRI tomographs?
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What is required for creating an MR image?
What is required for creating an MR image?
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Is it necessary to administer DTPA in a room with negative pressure?
Is it necessary to administer DTPA in a room with negative pressure?
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Is Xe 133 gas administered by use of a nebulizer?
Is Xe 133 gas administered by use of a nebulizer?
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What type(s) of radiation are being measured when a Geiger counter is used to measure a radioactive source with its cover removed?
What type(s) of radiation are being measured when a Geiger counter is used to measure a radioactive source with its cover removed?
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'Baseline shift' and 'pulse pile-up' are most likely to occur in situations with:
'Baseline shift' and 'pulse pile-up' are most likely to occur in situations with:
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'Dead time' is the minimum time separation between two radiation events that is required for them to be detected as two separate events. Is this statement:
'Dead time' is the minimum time separation between two radiation events that is required for them to be detected as two separate events. Is this statement:
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Which of the following will improve image contrast?
Which of the following will improve image contrast?
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What kind of radiation is being measured when a Geiger counter is used to measure a radioactive source with its cover removed?
What kind of radiation is being measured when a Geiger counter is used to measure a radioactive source with its cover removed?
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What do radiation interactions in a gas-filled detector create?
What do radiation interactions in a gas-filled detector create?
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Where do the negative electrons migrate to in a gas-filled detector?
Where do the negative electrons migrate to in a gas-filled detector?
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True or False: Pulse mode operation of a gas-filled detector requires a high photon flux to produce an accurate reading.
True or False: Pulse mode operation of a gas-filled detector requires a high photon flux to produce an accurate reading.
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When a CT scan is used to correct for attenuation in a PET scan, is a single correction factor used for all tissues?
When a CT scan is used to correct for attenuation in a PET scan, is a single correction factor used for all tissues?
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Is it always true that an area of increased activity on the non-attenuation-corrected PET scan is a real hot spot?
Is it always true that an area of increased activity on the non-attenuation-corrected PET scan is a real hot spot?
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Is it necessary to administer Xe 133 gas by use of a nebulizer?
Is it necessary to administer Xe 133 gas by use of a nebulizer?
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Will baseline shift and pulse pile-up most likely occur in situations with high counting rates?
Will baseline shift and pulse pile-up most likely occur in situations with high counting rates?
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Which type of collimator has better resolution at the same object-collimator distance?
Which type of collimator has better resolution at the same object-collimator distance?
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What mainly determines a gamma camera’s extrinsic resolution?
What mainly determines a gamma camera’s extrinsic resolution?
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Which of the following will degrade contrast?
Which of the following will degrade contrast?
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In filtered backprojection, how does the filter work in the reconstruction?
In filtered backprojection, how does the filter work in the reconstruction?
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Which semiconductor material is used in commercial intraoperative probes?
Which semiconductor material is used in commercial intraoperative probes?
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What is the purpose of the photomultiplier tube in a scintillation detector?
What is the purpose of the photomultiplier tube in a scintillation detector?
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'Scintillators used for PET have different strengths. LSO has a short decay time, reducing the number of ________.' Fill in the blank.
'Scintillators used for PET have different strengths. LSO has a short decay time, reducing the number of ________.' Fill in the blank.
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'Scintillators used for PET have different strengths. GSO, with its improved energy resolution, allows for a greater exclusion of ____________.' Fill in the blank.
'Scintillators used for PET have different strengths. GSO, with its improved energy resolution, allows for a greater exclusion of ____________.' Fill in the blank.
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In which of the following SPECT studies is it acceptable to acquire with a 180º orbit?
In which of the following SPECT studies is it acceptable to acquire with a 180º orbit?
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True or false: In transmission imaging, one measures photons from an external source that pass through the object.
True or false: In transmission imaging, one measures photons from an external source that pass through the object.
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True or false: As many as half of all counts in a SPECT study may have been scattered before being registered in the gamma camera.
True or false: As many as half of all counts in a SPECT study may have been scattered before being registered in the gamma camera.
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Which of the following contributes the most to dead time?
Which of the following contributes the most to dead time?
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What is the purpose of a pulse height analyzer in a scintillation detector?
What is the purpose of a pulse height analyzer in a scintillation detector?
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Which of the following materials is used in commercial intraoperative probes?
Which of the following materials is used in commercial intraoperative probes?
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What function does a collimator serve in a gamma camera?
What function does a collimator serve in a gamma camera?
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Which of the following is a disadvantage of a digital image?
Which of the following is a disadvantage of a digital image?
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What is the function of a light pipe in the context of a gamma camera?
What is the function of a light pipe in the context of a gamma camera?
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What will improve the collimator's overall sensitivity?
What will improve the collimator's overall sensitivity?
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Which type of collimator would be suitable if part of the body being imaged is small compared to the camera’s field of view?
Which type of collimator would be suitable if part of the body being imaged is small compared to the camera’s field of view?
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What is the main cause of non-uniformity in a gamma camera?
What is the main cause of non-uniformity in a gamma camera?
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What determines a gamma camera's extrinsic resolution primarily?
What determines a gamma camera's extrinsic resolution primarily?
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What function does a position circuit serve?
What function does a position circuit serve?
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True or False: Septal penetration is more of a problem with lower-energy gamma rays than higher-energy gamma rays.
True or False: Septal penetration is more of a problem with lower-energy gamma rays than higher-energy gamma rays.
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What type(s) of radiation are being measured when a Geiger counter is used to measure a radioactive source with its cover removed?
What type(s) of radiation are being measured when a Geiger counter is used to measure a radioactive source with its cover removed?
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Which region of operation on the voltage-response curve is associated with a Geiger counter?
Which region of operation on the voltage-response curve is associated with a Geiger counter?
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What causes the change in charge on one or both plates of a gas-filled detector?
What causes the change in charge on one or both plates of a gas-filled detector?
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Which type of gas-filled detector requires a high photon flux for accurate readings in pulse mode operation?
Which type of gas-filled detector requires a high photon flux for accurate readings in pulse mode operation?
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What primarily determines a gamma camera's extrinsic resolution?
What primarily determines a gamma camera's extrinsic resolution?
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What is the purpose of the photomultiplier tube in a scintillation detector?
What is the purpose of the photomultiplier tube in a scintillation detector?
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'Dead time' is the minimum time separation between two radiation events that is required for them to be detected as two separate events. Is this statement:
'Dead time' is the minimum time separation between two radiation events that is required for them to be detected as two separate events. Is this statement:
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True or False: In transmission imaging, one measures photons from an external source that pass through the object.
True or False: In transmission imaging, one measures photons from an external source that pass through the object.
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According to the standard of practice, what should the percent energy resolution fall between for Cs137?
According to the standard of practice, what should the percent energy resolution fall between for Cs137?
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What is the minimum time separation required between two radiation events in order for them to be detected as two separate events?
What is the minimum time separation required between two radiation events in order for them to be detected as two separate events?
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Which of the following can be used as the stopping condition for a gamma camera image?
Which of the following can be used as the stopping condition for a gamma camera image?
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What mainly determines a gamma camera’s extrinsic resolution?
What mainly determines a gamma camera’s extrinsic resolution?
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Which type of collimator has better resolution at the same object-collimator distance?
Which type of collimator has better resolution at the same object-collimator distance?
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What is the function of a pulse height analyzer?
What is the function of a pulse height analyzer?
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Which of the following materials is used in commercial intraoperative probes?
Which of the following materials is used in commercial intraoperative probes?
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'Scintillators used for PET have different strengths. BGO has high stopping power for 511 keV photons and therefore maximizes the ________ detected.' Fill in the blank.
'Scintillators used for PET have different strengths. BGO has high stopping power for 511 keV photons and therefore maximizes the ________ detected.' Fill in the blank.
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'Scintillators used for PET have different strengths. GSO, with its improved energy resolution, allows for a greater exclusion of ____________.' Fill in the blank.
'Scintillators used for PET have different strengths. GSO, with its improved energy resolution, allows for a greater exclusion of ____________.' Fill in the blank.
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'Scintillators used for PET have different strengths. LSO has a short decay time, reducing the number of ________.' Fill in the blank.
'Scintillators used for PET have different strengths. LSO has a short decay time, reducing the number of ________.' Fill in the blank.
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Which of the following will improve image contrast?
Which of the following will improve image contrast?
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In which of the following SPECT studies is it acceptable to acquire with a 180º orbit?
In which of the following SPECT studies is it acceptable to acquire with a 180º orbit?
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Which of the following does NOT degrade contrast?
Which of the following does NOT degrade contrast?
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True or false? In transmission imaging, one measures photons from an external source that pass through the object.
True or false? In transmission imaging, one measures photons from an external source that pass through the object.
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Which of the following semiconductor materials is used in commercial intraoperative probes?
Which of the following semiconductor materials is used in commercial intraoperative probes?
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The purpose of the photomultiplier tube in a scintillation detector is to:
The purpose of the photomultiplier tube in a scintillation detector is to:
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'Scintillators used for PET have different strengths. LSO has a short decay time, reducing the number of ________.' Fill in the blank.
'Scintillators used for PET have different strengths. LSO has a short decay time, reducing the number of ________.' Fill in the blank.
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'Scintillators used for PET have different strengths. BGO has high stopping power for 511 keV photons and therefore maximizes the ________ detected.' Fill in the blank.
'Scintillators used for PET have different strengths. BGO has high stopping power for 511 keV photons and therefore maximizes the ________ detected.' Fill in the blank.
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'Scintillators used for PET have different strengths. GSO, with its improved energy resolution, allows for a greater exclusion of ____________.' Fill in the blank.
'Scintillators used for PET have different strengths. GSO, with its improved energy resolution, allows for a greater exclusion of ____________.' Fill in the blank.
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True or false? Attenuation is more of a problem with PET than it is with single-photon imaging.
True or false? Attenuation is more of a problem with PET than it is with single-photon imaging.
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Which of the following is NOT true about the use of a CT scan to correct for attenuation in a PET scan?
Which of the following is NOT true about the use of a CT scan to correct for attenuation in a PET scan?
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Is it always true that an area of increased activity on the non-attenuation-corrected PET scan is a real hot spot?
Is it always true that an area of increased activity on the non-attenuation-corrected PET scan is a real hot spot?
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What type of magnets are generally used in clinical MRI tomographs?
What type of magnets are generally used in clinical MRI tomographs?
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True or false: DTPA administration must be done in a room with negative pressure?
True or false: DTPA administration must be done in a room with negative pressure?
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True or false: Xe 133 gas is administered by use of a nebulizer?
True or false: Xe 133 gas is administered by use of a nebulizer?
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When a Geiger counter is used to measure a radioactive source and its cover is removed, what type(s) of radiation are being measured?
When a Geiger counter is used to measure a radioactive source and its cover is removed, what type(s) of radiation are being measured?
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'Baseline shift' and 'pulse pile-up' are most likely to occur in situations with:
'Baseline shift' and 'pulse pile-up' are most likely to occur in situations with:
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'Dead time' is the minimum time separation between two radiation events that is required for them to be detected as two separate events. Is this statement:
'Dead time' is the minimum time separation between two radiation events that is required for them to be detected as two separate events. Is this statement:
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Which of the following will improve image contrast?
Which of the following will improve image contrast?
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'Creating an MR image requires: Atoms with an unpaired proton.' True or false?
'Creating an MR image requires: Atoms with an unpaired proton.' True or false?
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In PET scans using CT corrections, is a single correction factor used for all tissues?
In PET scans using CT corrections, is a single correction factor used for all tissues?
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Is it necessary to administer Xe 133 gas by use of a nebulizer?
Is it necessary to administer Xe 133 gas by use of a nebulizer?
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Will baseline shift and pulse pile-up most likely occur in situations with low counting rates?
Will baseline shift and pulse pile-up most likely occur in situations with low counting rates?
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Is it always true that an area of increased activity on the non-attenuation-corrected PET scan is a real hot spot?
Is it always true that an area of increased activity on the non-attenuation-corrected PET scan is a real hot spot?
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Does pulse mode operation of a gas-filled detector require a high photon flux to produce an accurate reading?
Does pulse mode operation of a gas-filled detector require a high photon flux to produce an accurate reading?
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What determines a gamma camera's extrinsic resolution primarily?
What determines a gamma camera's extrinsic resolution primarily?
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What kind of radiation is being measured when a Geiger counter is used to measure a radioactive source with its cover removed?
What kind of radiation is being measured when a Geiger counter is used to measure a radioactive source with its cover removed?
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Which of the following contributes the most to dead time?
Which of the following contributes the most to dead time?
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Which of the following will degrade contrast?
Which of the following will degrade contrast?
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Study Notes
Radiation Measurement and Detectors
- When a Geiger counter is used to measure a radioactive source with its cover removed, it measures alpha, beta, and gamma radiation.
- In a gas-filled detector, radiation interactions create ion pairs.
- In a gas-filled detector, negative electrons migrate to the anode.
Pulse Height Analyzer and Collimators
- A pulse height analyzer is used to analyze the energy spectrum of radiation.
- A collimator is used to restrict the angle of incidence of radiation on a detector.
- A high-resolution collimator has smaller holes and is used for high-quality images of small objects.
Gamma Cameras and SPECT
- The extrinsic resolution of a gamma camera is mainly determined by the collimator.
- A 180º orbit is acceptable for some SPECT studies.
- In filtered backprojection, the filter works in the reconstruction to reduce noise.
Scintillators and PET
- BGO has high stopping power for 511 keV photons, maximizing detection.
- LSO has a short decay time, reducing the number of random coincidences.
- GSO has improved energy resolution, allowing for a greater exclusion of scattered photons.
Image Contrast and Resolution
- High-energy gamma rays are more susceptible to septal penetration.
- A high-resolution collimator and a large matrix size can improve image contrast.
- Dead time is the minimum time separation between two radiation events required to detect them as separate events.
MRI and X-Ray
- Clinical MRI tomographs use superconducting magnets.
- DTPA administration does not require a room with negative pressure.
- Xe 133 gas is administered using a nebulizer.
Miscellaneous
- Pulse mode operation of a gas-filled detector requires a high photon flux to produce an accurate reading.
- Baseline shift and pulse pile-up occur in situations with high counting rates.
- A position circuit serves to determine the position of radiation detection events.
- A light pipe is used to transmit light from the scintillator to the photomultiplier tube in a gamma camera.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on gamma camera resolution and collimators with this quiz. Determine whether statements about pinhole and parallel-hole collimators, as well as the extrinsic resolution of a gamma camera, are true or false. Additionally, identify components of background counts in nuclear medicine images.
