Nuclear Medicine Exit Exam Imaging
Physics Radiopharmaceuticals Clinical
Procedures Actual Exam 2026/2027 with
Detailed Rationales | Complete
Exam-Style Questions | Pass Guaranteed
– A+ Graded
Q1: A Tc-99m generator is eluted and the eluate shows 0.15 µCi of Mo-99 per mCi of Tc-99m. What
is the appropriate action?
A. The eluate is acceptable for patient administration
B. Repeat the elution after 24 hours
C. Discard the eluate and notify the RSO
D. The eluate exceeds the USP limit of 0.15 µCi Mo-99 per mCi Tc-99m and must be discarded
[CORRECT]
Correct Answer: D
Rationale: Correct because the USP limit for Mo-99 breakthrough is 0.15 µCi Mo-99 per mCi
Tc-99m. Exceeding this limit requires discarding the eluate and notifying the Radiation Safety
Officer to investigate generator integrity.
Q2: A patient receives 25 mCi of Tc-99m MDP for a bone scan. If the physical half-life of Tc-99m is
6.0 hours and the biological half-life for bone is 24 hours, what is the effective half-life?
A. 4.0 hours
B. 5.2 hours
C. 4.8 hours [CORRECT]
D. 6.5 hours
Correct Answer: C
,Rationale: Correct because effective half-life is calculated using 1/T_eff = 1/T_phys + 1/T_bio = 1/6
+ 1/24 = 5/24, therefore T_eff = 24/5 = 4.8 hours.
Q3: What is the primary purpose of the thallium dopant in a NaI(Tl) scintillation crystal?
A. To increase the density of sodium iodide
B. To prevent hygroscopic degradation
C. To create luminescence centers that convert deposited energy into visible light [CORRECT]
D. To reduce photomultiplier tube noise
Correct Answer: C
Rationale: Correct because thallium atoms in the NaI crystal lattice create luminescence centers
that efficiently convert deposited gamma ray energy into visible light photons detectable by the
PMT photocathode.
Q4: During a myocardial perfusion imaging study, a patient demonstrates a reversible perfusion
defect in the inferior wall on stress images that normalizes on rest images. What is the most likely
interpretation?
A. Prior myocardial infarction with scar
B. Attenuation artifact from the diaphragm
C. Ischemia in the right coronary artery territory [CORRECT]
D. Normal variant finding
Correct Answer: C
Rationale: Correct because a reversible perfusion defect indicates stress-induced ischemia in the
vascular territory supplied by the right coronary artery, as the defect resolves at rest when
myocardial oxygen demand decreases.
Q5: What is the NRC annual occupational whole-body dose limit for a radiation worker?
A. 1 mSv
B. 10 mSv
C. 50 mSv [CORRECT]
D. 100 mSv
Correct Answer: C
Rationale: Correct because NRC regulations specify a 50 mSv (5 rem) annual whole-body dose
limit for occupationally exposed individuals, with a cumulative limit of 10 mSv × age in years.
Q6: In PET imaging, what is the energy of each annihilation photon produced when a positron
encounters an electron?
A. 140 keV
B. 364 keV
,C. 511 keV [CORRECT]
D. 662 keV
Correct Answer: C
Rationale: Correct because positron-electron annihilation produces two 511 keV photons emitted at
nearly 180 degrees apart, which is the fundamental detection principle of PET imaging.
Q7: A dose calibrator is tested daily with a Cs-137 source and reads 98.5% of the expected value.
What action is required?
A. Replace the ionization chamber
B. Perform a full accuracy test
C. Document the result and continue use if within ±5% [CORRECT]
D. Send the unit for repair immediately
Correct Answer: C
Rationale: Correct because daily constancy testing requires the measured activity to be within ±5%
of the expected value; 98.5% falls within acceptable limits and should be documented in the QC
log.
Q8: Which collimator type provides the highest spatial resolution for thyroid imaging with Tc-99m
pertechnetate?
A. Parallel-hole high-sensitivity collimator
B. Diverging collimator
C. Converging collimator
D. Pinhole collimator [CORRECT]
Correct Answer: D
Rationale: Correct because the pinhole collimator provides the highest spatial resolution for small
organs like the thyroid by creating a magnified image through a single small aperture, though with
reduced sensitivity.
Q9: A patient with suspected pulmonary embolism undergoes V/Q scanning. The perfusion scan
shows multiple segmental defects with normal ventilation. What is the PIOPED interpretation?
A. Low probability
B. Intermediate probability
C. High probability [CORRECT]
D. Normal study
Correct Answer: C
, Rationale: Correct because multiple segmental perfusion defects with normal ventilation
(mismatched defects) meet high probability criteria for acute pulmonary embolism under modified
PIOPED interpretation.
Q10: What is the primary photon energy of Tc-99m used for gamma camera imaging?
A. 80 keV
B. 103 keV
C. 140 keV [CORRECT]
D. 364 keV
Correct Answer: C
Rationale: Correct because Tc-99m decays by isomeric transition emitting a 140 keV gamma
photon with approximately 89% abundance, which is optimal for gamma camera detection with
NaI(Tl) crystals.
Q11: During a hepatobiliary scan with Tc-99m mebrofenin, the gallbladder is not visualized by 60
minutes. What is the most appropriate next step?
A. Terminate the study and diagnose chronic cholecystitis
B. Administer morphine sulfate to accelerate bile flow
C. Continue imaging up to 4 hours or administer morphine augmentation [CORRECT]
D. Switch to Tc-99m DISIDA immediately
Correct Answer: C
Rationale: Correct because nonvisualization of the gallbladder at 60 minutes requires continued
imaging or morphine augmentation to distinguish acute cholecystitis (persistent nonvisualization)
from delayed filling due to chronic cholecystitis or prolonged fasting.
Q12: What is the physical half-life of F-18 fluorodeoxyglucose (FDG)?
A. 6.0 hours
B. 109.8 minutes [CORRECT]
C. 8.0 days
D. 13.2 hours
Correct Answer: B
Rationale: Correct because F-18 has a physical half-life of approximately 109.8 minutes (1.83
hours), which is ideal for PET imaging allowing sufficient time for radiopharmaceutical distribution
and imaging.
Q13: In SPECT imaging, what is the primary advantage of iterative reconstruction (OSEM) over
filtered backprojection?
Physics Radiopharmaceuticals Clinical
Procedures Actual Exam 2026/2027 with
Detailed Rationales | Complete
Exam-Style Questions | Pass Guaranteed
– A+ Graded
Q1: A Tc-99m generator is eluted and the eluate shows 0.15 µCi of Mo-99 per mCi of Tc-99m. What
is the appropriate action?
A. The eluate is acceptable for patient administration
B. Repeat the elution after 24 hours
C. Discard the eluate and notify the RSO
D. The eluate exceeds the USP limit of 0.15 µCi Mo-99 per mCi Tc-99m and must be discarded
[CORRECT]
Correct Answer: D
Rationale: Correct because the USP limit for Mo-99 breakthrough is 0.15 µCi Mo-99 per mCi
Tc-99m. Exceeding this limit requires discarding the eluate and notifying the Radiation Safety
Officer to investigate generator integrity.
Q2: A patient receives 25 mCi of Tc-99m MDP for a bone scan. If the physical half-life of Tc-99m is
6.0 hours and the biological half-life for bone is 24 hours, what is the effective half-life?
A. 4.0 hours
B. 5.2 hours
C. 4.8 hours [CORRECT]
D. 6.5 hours
Correct Answer: C
,Rationale: Correct because effective half-life is calculated using 1/T_eff = 1/T_phys + 1/T_bio = 1/6
+ 1/24 = 5/24, therefore T_eff = 24/5 = 4.8 hours.
Q3: What is the primary purpose of the thallium dopant in a NaI(Tl) scintillation crystal?
A. To increase the density of sodium iodide
B. To prevent hygroscopic degradation
C. To create luminescence centers that convert deposited energy into visible light [CORRECT]
D. To reduce photomultiplier tube noise
Correct Answer: C
Rationale: Correct because thallium atoms in the NaI crystal lattice create luminescence centers
that efficiently convert deposited gamma ray energy into visible light photons detectable by the
PMT photocathode.
Q4: During a myocardial perfusion imaging study, a patient demonstrates a reversible perfusion
defect in the inferior wall on stress images that normalizes on rest images. What is the most likely
interpretation?
A. Prior myocardial infarction with scar
B. Attenuation artifact from the diaphragm
C. Ischemia in the right coronary artery territory [CORRECT]
D. Normal variant finding
Correct Answer: C
Rationale: Correct because a reversible perfusion defect indicates stress-induced ischemia in the
vascular territory supplied by the right coronary artery, as the defect resolves at rest when
myocardial oxygen demand decreases.
Q5: What is the NRC annual occupational whole-body dose limit for a radiation worker?
A. 1 mSv
B. 10 mSv
C. 50 mSv [CORRECT]
D. 100 mSv
Correct Answer: C
Rationale: Correct because NRC regulations specify a 50 mSv (5 rem) annual whole-body dose
limit for occupationally exposed individuals, with a cumulative limit of 10 mSv × age in years.
Q6: In PET imaging, what is the energy of each annihilation photon produced when a positron
encounters an electron?
A. 140 keV
B. 364 keV
,C. 511 keV [CORRECT]
D. 662 keV
Correct Answer: C
Rationale: Correct because positron-electron annihilation produces two 511 keV photons emitted at
nearly 180 degrees apart, which is the fundamental detection principle of PET imaging.
Q7: A dose calibrator is tested daily with a Cs-137 source and reads 98.5% of the expected value.
What action is required?
A. Replace the ionization chamber
B. Perform a full accuracy test
C. Document the result and continue use if within ±5% [CORRECT]
D. Send the unit for repair immediately
Correct Answer: C
Rationale: Correct because daily constancy testing requires the measured activity to be within ±5%
of the expected value; 98.5% falls within acceptable limits and should be documented in the QC
log.
Q8: Which collimator type provides the highest spatial resolution for thyroid imaging with Tc-99m
pertechnetate?
A. Parallel-hole high-sensitivity collimator
B. Diverging collimator
C. Converging collimator
D. Pinhole collimator [CORRECT]
Correct Answer: D
Rationale: Correct because the pinhole collimator provides the highest spatial resolution for small
organs like the thyroid by creating a magnified image through a single small aperture, though with
reduced sensitivity.
Q9: A patient with suspected pulmonary embolism undergoes V/Q scanning. The perfusion scan
shows multiple segmental defects with normal ventilation. What is the PIOPED interpretation?
A. Low probability
B. Intermediate probability
C. High probability [CORRECT]
D. Normal study
Correct Answer: C
, Rationale: Correct because multiple segmental perfusion defects with normal ventilation
(mismatched defects) meet high probability criteria for acute pulmonary embolism under modified
PIOPED interpretation.
Q10: What is the primary photon energy of Tc-99m used for gamma camera imaging?
A. 80 keV
B. 103 keV
C. 140 keV [CORRECT]
D. 364 keV
Correct Answer: C
Rationale: Correct because Tc-99m decays by isomeric transition emitting a 140 keV gamma
photon with approximately 89% abundance, which is optimal for gamma camera detection with
NaI(Tl) crystals.
Q11: During a hepatobiliary scan with Tc-99m mebrofenin, the gallbladder is not visualized by 60
minutes. What is the most appropriate next step?
A. Terminate the study and diagnose chronic cholecystitis
B. Administer morphine sulfate to accelerate bile flow
C. Continue imaging up to 4 hours or administer morphine augmentation [CORRECT]
D. Switch to Tc-99m DISIDA immediately
Correct Answer: C
Rationale: Correct because nonvisualization of the gallbladder at 60 minutes requires continued
imaging or morphine augmentation to distinguish acute cholecystitis (persistent nonvisualization)
from delayed filling due to chronic cholecystitis or prolonged fasting.
Q12: What is the physical half-life of F-18 fluorodeoxyglucose (FDG)?
A. 6.0 hours
B. 109.8 minutes [CORRECT]
C. 8.0 days
D. 13.2 hours
Correct Answer: B
Rationale: Correct because F-18 has a physical half-life of approximately 109.8 minutes (1.83
hours), which is ideal for PET imaging allowing sufficient time for radiopharmaceutical distribution
and imaging.
Q13: In SPECT imaging, what is the primary advantage of iterative reconstruction (OSEM) over
filtered backprojection?
