NMTCB PET Questions
The exposure rate of an activity of 1 millicurie (mCi) measured at 1 centimeter (cm) is
called - answer- The exposure rate constant (ERC)
For positron emitters, the exposure rate constant (ERC) is about 6 R/h per millicurie at 1
cm. The exposure rate of a 10 mCi dose of F-18 is approximately six times greater than
that of a 10 mCi dose of Tc-99 m at a distance of approxi- mutely 8 inches.
Quantitative bias that refers to the underestimation of counts density which differs from
what they should be is called: - answer Partial-volume effect
PVE is caused by the finite spatial resolution of the imaging system which reveals how
far the signal "spills out" around its actual location. The signal spreading falsely
increases the object size and volume. Image sampling, where voxels in ROI include the
signal from underlying tissues, also contributes to the phenomenon known as partial-
volume effect.
Truncation artifacts in PET/CT imaging are produced by - answer Difference in size of
FOV between PET and the CT
Discrepancy between fields of view (FOVs) in a PET/CT scanner—70 cm causes a
truncation artifact when imaging extends beyond the CT FOV-50 cm; as a result no
attenuation correction values for the truncated anatomy are being applied.
Dental fillings, hip prosthetics, or chemotherapy port are examples of PET/CT imaging
artifacts described as: - answerMetallic implants artifacts
Metallic implants create streaking artifacts on CT images because of their high photon
absorption. Higher Hounsfield numbers consequently produce high PET attenuation
coefficients and an overestimation of PET findings.
The Property of PET detectors that allows them faster timing signals for coincidence
detection and to work at high count rates is called: - answerThe decay constant
The decay constant decides how long the scintillation flashes in the crystal; a short
decay time reduces detector dead time and as a result higher annihilation rates can be
accepted.
The picturing, description, and measurement of biological processes at the particle and
cellular level is known as - answerMolecular imaging
Radionuclide originated molecular imaging techniques such as positron emission
tomography
(PET) and single-photon emission computed tomography (SPECT) capture functional or
phenotypic changes associated with pathology and unfold the molecular abnormalities
responsible to form basis of many diseases.
,A PET system capacity to distinguish between two points after image reconstruction is
called: - answerResolution
A PET system resolution, according to NEMA guidelines, is assessed by imaging a
point source in the air and reconstructing the images with no smoothing or
transformation of images. The resolution of the system is affected by the annihilation
ambiguities, the detector ring diameter and the size of the scintillation crystal.
Allergic reaction that begins within seconds/minutes of contrast media administration
and rapidly progresses to cause airway constriction, skin and intestinal irritation, and
altered heart rhythms is called: - answerAnaphylaxis
The first PET radiopharmaceutical to receive the U.S. Food and Drug Administration
approval in 1989 was: - answerRb-82
The dose calibrator quality control procedure performed to assess the device's ability to
measure accurately a range of a low to high activities is called: - answerLinearity
The following positron-emitting radionuclides are isotopes of natural elements present in
most biochemical processes EXCEPT:
(A) O-15
(B) F-18
(C) C-11
(D) N-13 - answerF-18
Two photons arising from the same annihilation event and detected by two detectors
within the coincidence time-window are: - answerTrue coincidences
Serves as the building blocks for proteins synthesis - answerAmino acids
Positronium (Ps) is an arrangement of: - answerAn electron and a positron
The most common site of brown fat localization - answerNeck
Scintillator commonly used in PET imaging that has the highest stopping power -
answerBGO (bismuth germinate)
A malignant neoplasm of the skin linked with approximately 75% of skin cancer-related
mortality is called: - answerMelanoma
PET tracers have demonstrated significant potential utility and application in the
following clinical areas EXCEPT:
(A) Oncology
(B) Cardiology
(C) Pulmonology
(D) Neurology - answerC - Pulmonology
,The sum of the weighted equivalent doses in all the tissues and organs of the body is
called: - answerEffective dose
The combined whole-body effective dose for a clinically diagnostic PET/CT is typically in
the range: - answer20-30 mSv
The positron has the same mass as an electron and an electric charge of: - answer+ 1
The initial diagnosis of melanoma is established by: - answerHistologic evaluation
In PET scanning process raw data acquired and identified as coincidence events along
their LOR are stored in the raw data format called: - answerSinograms
Cyclotron produced positron-emitting radionuclide - answerNitrogen-13
A piece of equipment that sorts out photons of different radionuclides with different
photon energies and to separate scattered photons from the useful ones is called: -
answerPulse height analyzer
DNA synthesis is a measure of cellular: - answerProliferation
The F-18 fluoride bone uptake mechanism is similar to that of: - answerTc-99 m
methylenediphosphonate (MDP)
The process by which new blood vessels are formed is called: - answerAngiogenesis
Quality control procedures required for proper functioning of the survey meter -
answerCalibration and constancy
The Circle of Willis is a circle of arteries that supply blood to: - answerThe brain
What is the purpose of the CT X-ray tube: - answerProduces the X-ray
The radiodensity of distilled water at standard pressure and temperature (STP) on the
Hounsfield unit (HU) scale is equal to: - answer0 HU
The dose calibrator quality control procedure testing a long-lived standard at each of the
frequently used radionuclides settings is called: - answerConstancy
Which of the following radionuclides commonly used in PET imaging has the highest
energy?
(A) Carbon-11
(B) Nitrogen-13
(C) Oxygen-15
(D) Fluorine-18 - answer(C) Oxygen-15 1.72 MeV
, Carbon-11 0.96 MeV
Nitrogen-13 1.19 MeV
Fluorine-18 0.635 MeV
The PET scanner quality control procedure in which data are used with the transmission
data in the computation of attenuation correction factors is called: - answerBlank scan
The property of the scintillation detector described as the number of scintillations
produced by each incident photon is called: - answerThe light output
Precursor for the synthesis of phospholipids - answerCholine
The correct order of scanning when a typical PET/CT protocol is applied -
answerTopogram, transmission CT, emission PET
Presence of the non-collinearity of the annihilation photons and the finite positron range
are inherent properties of positron emission tomography resulting in: - answerPositional
inaccuracy
Which of the following positron-emitting nuclides has the shortest half-life?
(A) Rubidium-82
(B) Oxygen-15
(C) Nitrogen-13
(D) Carbon-11 - answer(A) Rubidium-82 75 Seconds
Oxygen-15 2 minutes
Nitrogen-13 10 minutes
Carbon-11 20 minutes
What is the purpose of the cathode filament of the X-ray tube: - answerEmits electrons
An oncology patient referred for a positron emission tomography scan should fast prior
to his/her appointment for at least: - answer4 hours
When should Daily quality control checks on the PET scanner be performed? -
answerBefore the patient is injected
Patients with malignant melanoma should be scanned with their arms: - answerDown
The presence of asbestos-related plaques, benign inflammatory pleuritis, tuberculous
pleuritis, and pleural effusion can result in - answerFalse-positive uptake in FDG-PET
images of patients with malignant mesothelioma
The earliest disposal of the decay-in-storage waste material is permitted if it was held
for a minimum 10 half-lives and has decayed to less than: - answerTwo times
background levels
The exposure rate of an activity of 1 millicurie (mCi) measured at 1 centimeter (cm) is
called - answer- The exposure rate constant (ERC)
For positron emitters, the exposure rate constant (ERC) is about 6 R/h per millicurie at 1
cm. The exposure rate of a 10 mCi dose of F-18 is approximately six times greater than
that of a 10 mCi dose of Tc-99 m at a distance of approxi- mutely 8 inches.
Quantitative bias that refers to the underestimation of counts density which differs from
what they should be is called: - answer Partial-volume effect
PVE is caused by the finite spatial resolution of the imaging system which reveals how
far the signal "spills out" around its actual location. The signal spreading falsely
increases the object size and volume. Image sampling, where voxels in ROI include the
signal from underlying tissues, also contributes to the phenomenon known as partial-
volume effect.
Truncation artifacts in PET/CT imaging are produced by - answer Difference in size of
FOV between PET and the CT
Discrepancy between fields of view (FOVs) in a PET/CT scanner—70 cm causes a
truncation artifact when imaging extends beyond the CT FOV-50 cm; as a result no
attenuation correction values for the truncated anatomy are being applied.
Dental fillings, hip prosthetics, or chemotherapy port are examples of PET/CT imaging
artifacts described as: - answerMetallic implants artifacts
Metallic implants create streaking artifacts on CT images because of their high photon
absorption. Higher Hounsfield numbers consequently produce high PET attenuation
coefficients and an overestimation of PET findings.
The Property of PET detectors that allows them faster timing signals for coincidence
detection and to work at high count rates is called: - answerThe decay constant
The decay constant decides how long the scintillation flashes in the crystal; a short
decay time reduces detector dead time and as a result higher annihilation rates can be
accepted.
The picturing, description, and measurement of biological processes at the particle and
cellular level is known as - answerMolecular imaging
Radionuclide originated molecular imaging techniques such as positron emission
tomography
(PET) and single-photon emission computed tomography (SPECT) capture functional or
phenotypic changes associated with pathology and unfold the molecular abnormalities
responsible to form basis of many diseases.
,A PET system capacity to distinguish between two points after image reconstruction is
called: - answerResolution
A PET system resolution, according to NEMA guidelines, is assessed by imaging a
point source in the air and reconstructing the images with no smoothing or
transformation of images. The resolution of the system is affected by the annihilation
ambiguities, the detector ring diameter and the size of the scintillation crystal.
Allergic reaction that begins within seconds/minutes of contrast media administration
and rapidly progresses to cause airway constriction, skin and intestinal irritation, and
altered heart rhythms is called: - answerAnaphylaxis
The first PET radiopharmaceutical to receive the U.S. Food and Drug Administration
approval in 1989 was: - answerRb-82
The dose calibrator quality control procedure performed to assess the device's ability to
measure accurately a range of a low to high activities is called: - answerLinearity
The following positron-emitting radionuclides are isotopes of natural elements present in
most biochemical processes EXCEPT:
(A) O-15
(B) F-18
(C) C-11
(D) N-13 - answerF-18
Two photons arising from the same annihilation event and detected by two detectors
within the coincidence time-window are: - answerTrue coincidences
Serves as the building blocks for proteins synthesis - answerAmino acids
Positronium (Ps) is an arrangement of: - answerAn electron and a positron
The most common site of brown fat localization - answerNeck
Scintillator commonly used in PET imaging that has the highest stopping power -
answerBGO (bismuth germinate)
A malignant neoplasm of the skin linked with approximately 75% of skin cancer-related
mortality is called: - answerMelanoma
PET tracers have demonstrated significant potential utility and application in the
following clinical areas EXCEPT:
(A) Oncology
(B) Cardiology
(C) Pulmonology
(D) Neurology - answerC - Pulmonology
,The sum of the weighted equivalent doses in all the tissues and organs of the body is
called: - answerEffective dose
The combined whole-body effective dose for a clinically diagnostic PET/CT is typically in
the range: - answer20-30 mSv
The positron has the same mass as an electron and an electric charge of: - answer+ 1
The initial diagnosis of melanoma is established by: - answerHistologic evaluation
In PET scanning process raw data acquired and identified as coincidence events along
their LOR are stored in the raw data format called: - answerSinograms
Cyclotron produced positron-emitting radionuclide - answerNitrogen-13
A piece of equipment that sorts out photons of different radionuclides with different
photon energies and to separate scattered photons from the useful ones is called: -
answerPulse height analyzer
DNA synthesis is a measure of cellular: - answerProliferation
The F-18 fluoride bone uptake mechanism is similar to that of: - answerTc-99 m
methylenediphosphonate (MDP)
The process by which new blood vessels are formed is called: - answerAngiogenesis
Quality control procedures required for proper functioning of the survey meter -
answerCalibration and constancy
The Circle of Willis is a circle of arteries that supply blood to: - answerThe brain
What is the purpose of the CT X-ray tube: - answerProduces the X-ray
The radiodensity of distilled water at standard pressure and temperature (STP) on the
Hounsfield unit (HU) scale is equal to: - answer0 HU
The dose calibrator quality control procedure testing a long-lived standard at each of the
frequently used radionuclides settings is called: - answerConstancy
Which of the following radionuclides commonly used in PET imaging has the highest
energy?
(A) Carbon-11
(B) Nitrogen-13
(C) Oxygen-15
(D) Fluorine-18 - answer(C) Oxygen-15 1.72 MeV
, Carbon-11 0.96 MeV
Nitrogen-13 1.19 MeV
Fluorine-18 0.635 MeV
The PET scanner quality control procedure in which data are used with the transmission
data in the computation of attenuation correction factors is called: - answerBlank scan
The property of the scintillation detector described as the number of scintillations
produced by each incident photon is called: - answerThe light output
Precursor for the synthesis of phospholipids - answerCholine
The correct order of scanning when a typical PET/CT protocol is applied -
answerTopogram, transmission CT, emission PET
Presence of the non-collinearity of the annihilation photons and the finite positron range
are inherent properties of positron emission tomography resulting in: - answerPositional
inaccuracy
Which of the following positron-emitting nuclides has the shortest half-life?
(A) Rubidium-82
(B) Oxygen-15
(C) Nitrogen-13
(D) Carbon-11 - answer(A) Rubidium-82 75 Seconds
Oxygen-15 2 minutes
Nitrogen-13 10 minutes
Carbon-11 20 minutes
What is the purpose of the cathode filament of the X-ray tube: - answerEmits electrons
An oncology patient referred for a positron emission tomography scan should fast prior
to his/her appointment for at least: - answer4 hours
When should Daily quality control checks on the PET scanner be performed? -
answerBefore the patient is injected
Patients with malignant melanoma should be scanned with their arms: - answerDown
The presence of asbestos-related plaques, benign inflammatory pleuritis, tuberculous
pleuritis, and pleural effusion can result in - answerFalse-positive uptake in FDG-PET
images of patients with malignant mesothelioma
The earliest disposal of the decay-in-storage waste material is permitted if it was held
for a minimum 10 half-lives and has decayed to less than: - answerTwo times
background levels
