Nuclear Medicine Technologist Prometric exam questions with answers

1. Question 1Clinical Proceduresmedium

   A three-phase bone scan shows increased flow, increased blood pool and increased delayed uptake in a single bone. What does this pattern suggest?

   1. ACellulitis
   2. BNormal variant
   3. COld healed fracture
   4. DOsteomyelitis
   Show answer and explanation▾

   Answer: D. Osteomyelitis

   All three phases are positive in osteomyelitis. In cellulitis the flow and blood pool phases are positive, but delayed uptake is diffuse and not focal in bone. A normal scan shows no focal uptake, and an old healed fracture is usually negative in the first two phases.

   Reference: Waterstram-Rich and Gilmore, Nuclear Medicine and PET/CT: Technology and Techniques, 8th ed. (2017)

2. Question 2Image Interpretation and Image Artifacthard

   A bone scan shows very intense, diffuse skeletal uptake with absent kidney and bladder activity. What does this pattern indicate?

   1. ASuperscan from diffuse metastatic disease
   2. BNormal variant in a child
   3. CPoor radiochemical purity with free pertechnetate
   4. DRenal tracer extravasation
   Show answer and explanation▾

   Answer: A. Superscan from diffuse metastatic disease

   A superscan has intense skeletal uptake with poor soft tissue and renal activity, typical of diffuse metastases such as prostate cancer. A normal child scan shows physeal uptake with visible kidneys. Free pertechnetate shows stomach and thyroid uptake, and extravasation gives a focal injection-site hot spot.

   Reference: Waterstram-Rich and Gilmore, Nuclear Medicine and PET/CT: Technology and Techniques, 8th ed. (2017)

3. Question 3Clinical Proceduresmedium

   What is the standardised protocol for a solid-phase gastric emptying study?

   1. ATc-99m DTPA liquid meal with a single 30-minute image
   2. BTc-99m MAA mixed with water, imaged once at 24 hours
   3. CTc-99m pertechnetate in a fatty meal, imaged once at 10 minutes
   4. DTc-99m sulfur colloid egg-white meal with images up to 4 hours
   Show answer and explanation▾

   Answer: D. Tc-99m sulfur colloid egg-white meal with images up to 4 hours

   The consensus protocol uses a Tc-99m sulfur colloid egg-white meal with imaging at baseline, 1, 2 and 4 hours. The other protocols do not give a validated retention curve.

   Reference: Waterstram-Rich and Gilmore, Nuclear Medicine and PET/CT: Technology and Techniques, 8th ed. (2017)

4. Question 4Clinical Proceduresmedium

   Why should blood not be drawn back into a syringe of Tc-99m MAA before injection?

   1. ABlood dilutes the particles and lowers the lung counts overall
   2. BBlood changes the particle size to below 10 micrometres in the vial
   3. CClots may trap particles and produce hot spots in the lungs
   4. DBlood reduces the Tc-99m labelling efficiency of the whole kit
   Show answer and explanation▾

   Answer: C. Clots may trap particles and produce hot spots in the lungs

   Drawing blood back can cause clots that trap MAA particles, giving focal hot spots on the lung scan. Dilution does not meaningfully change counts, particle size is not changed by blood, and labelling is already complete.

   Reference: Saha, Fundamentals of Nuclear Pharmacy, 7th ed. (2018)

5. Question 5Patient Careeasy

   What must be checked for all women of childbearing age before administering a radiopharmaceutical?

   1. ABlood pressure, heart rate, temperature and oxygen saturation
   2. BFasting status and time of the last meal
   3. CHeight, body weight and body mass index
   4. DPossible pregnancy, including last menstrual period
   Show answer and explanation▾

   Answer: D. Possible pregnancy, including last menstrual period

   Pregnancy status must be confirmed before administration so the physician can weigh the fetal dose. Blood pressure, fasting and height are not the key checks for this concern.

   Reference: Waterstram-Rich and Gilmore, Nuclear Medicine and PET/CT: Technology and Techniques, 8th ed. (2017)

6. Question 6Clinical Proceduresmedium

   On dual-phase Tc-99m sestamibi parathyroid imaging, what finding suggests a parathyroid adenoma?

   1. APersistent focal uptake on delayed images while thyroid activity washes out
   2. BEqual washout from the thyroid and the focal area on delayed images
   3. CAbsent early uptake in the thyroid with a normal delayed image
   4. DDiffuse uptake in the salivary glands on both the early and late images
   Show answer and explanation▾

   Answer: A. Persistent focal uptake on delayed images while thyroid activity washes out

   Adenomatous tissue retains sestamibi because of mitochondrial content while normal thyroid washes out faster. Equal washout does not identify a lesion. Absent thyroid uptake and salivary glands uptake are not signs of adenoma.

   Reference: Waterstram-Rich and Gilmore, Nuclear Medicine and PET/CT: Technology and Techniques, 8th ed. (2017)

7. Question 7Quality Controlhard

   What artefact on a reconstructed SPECT image results from a centre of rotation error?

   1. ARing or blurred artefact of a point source
   2. BCold spot over the whole image
   3. CUniform increase in noise
   4. DStreak artefact toward the edge of the field
   Show answer and explanation▾

   Answer: A. Ring or blurred artefact of a point source

   A centre-of-rotation error causes a point source to reconstruct as a ring or tuft and blurs structures. A global cold spot or uniform noise does not match the error. Streaks toward the field edge suggest truncation or very hot objects.

   Reference: Waterstram-Rich and Gilmore, Nuclear Medicine and PET/CT: Technology and Techniques, 8th ed. (2017)

8. Question 8Physics and Radiation Safetyeasy

   A source gives 100 microsieverts per hour at 1 metre. What is the approximate dose rate at 2 metres, ignoring shielding?

   1. A50 microsieverts per hour
   2. B12.5 microsieverts per hour
   3. C25 microsieverts per hour
   4. D75 microsieverts per hour
   Show answer and explanation▾

   Answer: C. 25 microsieverts per hour

   Dose rate follows the inverse square law, so doubling the distance cuts it to one quarter. Fifty would apply if it fell linearly, 12.5 would need a distance factor of about 2.8, and 75 does not follow any distance law.

   Reference: Cherry, Sorenson and Phelps, Physics in Nuclear Medicine, 4th ed. (2012)

9. Question 9Image Production / Processingmedium

   How is noise in a filtered back-projection SPECT image best controlled?

   1. AApply a low-pass filter such as Butterworth with a suitable cut-off
   2. BUse the ramp filter without extra smoothing
   3. CReduce the matrix size to 16 x 16 pixels
   4. DUse a high-pass filter with a high cut-off
   Show answer and explanation▾

   Answer: A. Apply a low-pass filter such as Butterworth with a suitable cut-off

   The ramp filter amplifies high-frequency noise, so a low-pass filter such as Butterworth is applied to limit it. The ramp filter alone worsens noise, a very small matrix loses resolution, and a high-pass filter increases noise.

   Reference: Cherry, Sorenson and Phelps, Physics in Nuclear Medicine, 4th ed. (2012)

10. Question 10Instrumentationmedium

    Which collimator should be used for imaging I-131, which emits 364 keV photons?

    1. AHigh-energy parallel-hole collimator
    2. BLow-energy high-resolution collimator
    3. CLow-energy all-purpose collimator
    4. DPinhole collimator with a thin aperture
    Show answer and explanation▾

    Answer: A. High-energy parallel-hole collimator

    The thicker septa of a high-energy collimator stop penetration by 364 keV photons. Low-energy collimators suffer septal penetration at this energy, which degrades the image. A pinhole is intended for small organs such as the thyroid at low energy.

    Reference: Waterstram-Rich and Gilmore, Nuclear Medicine and PET/CT: Technology and Techniques, 8th ed. (2017)

11. Question 11Management and Ethicsmedium

    A technologist realises the wrong radiopharmaceutical was given to a patient. What should be done first?

    1. ARepeat the scan the next day without recording the error in the patient file
    2. BInform the nuclear medicine physician and radiation safety officer and document the event
    3. CTell the patient about it if the patient asks about the dose given
    4. DRecord it in the department log at the end of the month
    Show answer and explanation▾

    Answer: B. Inform the nuclear medicine physician and radiation safety officer and document the event

    Medical errors must be reported promptly to the responsible physician and radiation safety officer and documented, so the patient can be managed and reporting duties met. Concealment and late reporting are unethical and breach policy.

    Reference: Waterstram-Rich and Gilmore, Nuclear Medicine and PET/CT: Technology and Techniques, 8th ed. (2017)

12. Question 12Radiopharmaceuticalseasy

    By what mechanism does Tc-99m MDP localise in bone?

    1. APhagocytosis by osteoclasts lining resorption lacunae
    2. BActive transport into osteoblasts by a sodium pump
    3. CCapillary blockage in the trabecular bone marrow
    4. DChemisorption onto hydroxyapatite crystals
    Show answer and explanation▾

    Answer: D. Chemisorption onto hydroxyapatite crystals

    Tc-99m diphosphonates bind to hydroxyapatite, mainly where blood flow and osteoblastic activity are high. Osteoclast phagocytosis, osteoblast transport and capillary blockage are not the mechanisms. Capillary blockage applies to MAA in the lungs.

    Reference: Saha, Fundamentals of Nuclear Pharmacy, 7th ed. (2018)

13. Question 13Patient Caremedium

    How are paediatric radiopharmaceutical activities usually determined?

    1. AThe same activity as for adults, scaled by height
    2. BScaled by body weight with a minimum activity, using a dosage card
    3. CScaled by age, using the adult activity as the maximum
    4. DHalf the adult activity for each child below ten years
    Show answer and explanation▾

    Answer: B. Scaled by body weight with a minimum activity, using a dosage card

    Body weight scaling using a consensus dosage card with minimum activities keeps images adequate and dose low. Using adult dosing overexposes children, and age-only or fixed halving does not fit body size.

    Reference: Lassmann and Treves, Paediatric radiopharmaceutical administration: harmonization of the 2007 EANM guideline and 2010 North American consensus guidelines (2014)

14. Question 14Physics and Radiation Safetymedium

    Which interaction is the main cause of photon scatter in soft tissue for 140 keV gamma rays?

    1. APhotoelectric absorption
    2. BCompton scatter
    3. CPair production
    4. DCoherent scatter
    Show answer and explanation▾

    Answer: B. Compton scatter

    At 140 keV in soft tissue Compton scatter dominates because soft tissue has a low atomic number. Photoelectric absorption dominates only at lower energies or in high-Z materials such as lead. Pair production needs photons above 1.022 MeV, and coherent scatter is a minor contribution.

    Reference: Cherry, Sorenson and Phelps, Physics in Nuclear Medicine, 4th ed. (2012)

15. Question 15Physics and Radiation Safetymedium

    A vial of Tc-99m sestamibi breaks and spills on the floor of the hot lab. Which action comes first?

    1. AWarn others, restrict the area and cover the spill with absorbent paper
    2. BMop the area with water and discard the mop in regular waste
    3. CEvacuate the department and clean the area the next morning
    4. DRemove contaminated shoes and continue working in the room
    Show answer and explanation▾

    Answer: A. Warn others, restrict the area and cover the spill with absorbent paper

    The first steps are to alert staff, limit access and contain the liquid with absorbent material, wearing gloves, before decontaminating from the outside in and surveying. Mopping spreads activity and wrongly uses ordinary waste. Leaving the spill unattended spreads contamination.

    Reference: Waterstram-Rich and Gilmore, Nuclear Medicine and PET/CT: Technology and Techniques, 8th ed. (2017)

Last reviewed September 2026. Questions are original and written to the published exam blueprint; they are not taken from any real paper.