ARRT Nuclear Medicine Exam Prep
Free ARRT nuclear medicine exam prep: where the scored questions are, 31 original, unofficial practice questions with full explanations, and an 8-week study plan.
Practice questions
Pick your answer, then open the explanation.
Patient Care
Question 1
Patient Care · Patient identification · NMT-01
Before injecting a Tc-99m radiopharmaceutical on an inpatient, which pair of identifiers meets the Joint Commission requirement?
Show answer and explanation for Question 1 (NMT-01)
Answer: C.
The Joint Commission requires at least two patient identifiers before giving medications or doing procedures. The patient's room number or physical location doesn't count as an identifier.
A uses only one identifier. B and D each lean on a location, so they really have only one.
Source: The Joint Commission, “Two Patient Identifiers—Understanding the Requirements”, “Intent,” updated April 21, 2026.
Question 2
Patient Care · Infection control · NMT-02
A technologist finishes positioning a patient and removes their gloves. The gloves were intact. Before touching the clean acquisition workstation, what should the technologist do?
Show answer and explanation for Question 2 (NMT-02)
Answer: A.
Gloves don't replace hand hygiene. CDC guidance is to clean your hands every time you remove gloves.
Intact gloves (B) don't change that, because hands can be contaminated during removal. Reusing gloves (C) defeats their purpose. D limits hand hygiene to visible dirt, which isn't the rule.
Source: CDC, Clinical Safety: Hand Hygiene for Healthcare Workers.
Question 3
Patient Care · Pharmacology · NMT-03
A patient arrives for a regadenoson pharmacologic stress myocardial perfusion study and mentions drinking two cups of coffee 3 hours ago. What is the most appropriate action?
Show answer and explanation for Question 3 (NMT-03)
Answer: B.
The regadenoson label tells patients to avoid methylxanthines, including caffeinated coffee and tea, for at least 12 hours before the study. Methylxanthines block adenosine receptors, which interferes with the drug's vasodilation.
The technologist doesn't change the protocol alone. The supervising physician decides whether to reschedule or switch stress methods.
C is wrong because regadenoson is a fixed 0.4 mg dose. D makes things worse: aminophylline is a methylxanthine used to reverse regadenoson.
Source: Lexiscan (regadenoson) prescribing information, sections 2 and 7.1.
Question 4
Patient Care · Pharmacology and emergencies · NMT-04
After regadenoson, a patient has severe, persistent chest discomfort and flushing but no seizure. The physician orders a drug to counteract regadenoson's effect on adenosine receptors. Which drug is it most likely to be?
Show answer and explanation for Question 4 (NMT-04)
Answer: D.
The label says aminophylline may be used to lessen severe or persistent adverse reactions to regadenoson. Aminophylline is a methylxanthine that blocks adenosine receptors.
Atropine treats slow heart rates. Dobutamine is a different stress agent. Naloxone reverses opioids. None of them reverses adenosine-receptor stimulation.
Aminophylline is not recommended for a seizure associated with regadenoson; it can increase seizure risk.
Source: Lexiscan prescribing information, sections 5.8, 7.1 and 10.
Safety
Question 5
Safety · NRC dose limits · NMT-05
Under NRC rules, what is the annual occupational dose limit to the lens of the eye for an adult radiation worker?
Show answer and explanation for Question 5 (NMT-05)
Answer: C.
The lens dose equivalent limit is 15 rem (0.15 Sv) per year.
Keep these annual limits distinct:
- Total effective dose equivalent: 5 rem (0.05 Sv)
- Lens of the eye: 15 rem (0.15 Sv)
- Skin of the whole body or any extremity: 50 rem (0.5 Sv)
0.5 rem (A) is the general embryo/fetus limit over the entire pregnancy for a declared pregnant worker, subject to the declaration-time exception in Question 6. It is not a lens limit.
Sources: 10 CFR 20.1201(a); 10 CFR 20.1208(a), (d).
Question 6
Safety · NRC dose limits · NMT-06
A technologist formally declares her pregnancy to her employer. The estimated dose equivalent to the embryo/fetus from occupational exposure so far is 0.10 rem (1 mSv). What is the NRC dose limit to the embryo/fetus for the entire pregnancy?
Show answer and explanation for Question 6 (NMT-06)
Answer: A.
The limit is 0.5 rem (5 mSv) to the embryo/fetus for the entire pregnancy.
Watch the time period. The rule covers the whole pregnancy, not each month (B) or each trimester (D). 5 rem (C) is the adult worker's yearly limit.
There is a separate rule when the pregnancy is declared after substantial exposure: if the embryo/fetus dose has already exceeded 0.5 rem, or is within 0.05 rem (0.5 mSv) of that amount at declaration, no more than 0.05 rem additional dose is permitted for the remainder of the pregnancy. That is a remaining-pregnancy allowance, not the monthly limit in B.
Source: 10 CFR 20.1208(a), (b) and (d).
Question 7
Safety · Radiation protection · NMT-07
A small point source gives an exposure rate of 8 mR/h at 1 meter. Assume nothing changes except distance. What exposure rate is expected at 2 meters?
Show answer and explanation for Question 7 (NMT-07)
Answer: D.
The inverse square law says intensity falls with the square of distance. Doubling the distance cuts the rate to one-fourth:
8 × (1/2)² = 8 × 1/4 = 2 mR/h
A treats the relationship as straight division by distance. B divides by 8, as if distance were cubed. C goes the wrong direction.
The formula: I₂ = I₁ × (d₁/d₂)². It assumes a point source with no shielding in between. A patient is a spread-out source, so measured rates near a patient won't follow the law exactly.
Source: IAEA, Dosimetry for Radiopharmaceutical Therapy (2024), section 2.4.3, page 29 (point-source geometry). Calculation derived from the stated inputs.
Question 8
Safety · Radiation physics · NMT-08
A radiopharmaceutical has a physical half-life of 6 hours and a biological half-life of 3 hours. Assume radioactive decay and biological elimination act independently and each follows exponential loss. What is its effective half-life?
Show answer and explanation for Question 8 (NMT-08)
Answer: A.
T_eff = (T_p × T_b) ÷ (T_p + T_b) = (6 × 3) ÷ (6 + 3) = 18 ÷ 9 = 2 hours
In this model, the effective half-life is shorter than both the physical and biological half-lives. Decay and elimination remove activity at the same time. That rules out C and D right away. B comes from halving the shorter half-life, which isn't the formula.
Source: IAEA, Nuclear Medicine in Thyroid Cancer Management: A Practical Approach (IAEA-TECDOC-1608), section 12.4, pages 132–133, “Half-life—physical, biological and effective.” The calculation uses the stated model and inputs.
Question 9
Safety · Radioactive materials and regulations · NMT-09
A Tc-99m generator is eluted at 08:00. The eluate contains 1,000 mCi of Tc-99m and 100 µCi of Mo-99. A dose from this eluate will be given at 14:00, six hours later. Use a Tc-99m half-life of 6.02 hours and a Mo-99 half-life of 66 hours. What should the technologist conclude?
Show answer and explanation for Question 9 (NMT-09)
Answer: D.
The NRC limit is 0.15 µCi of Mo-99 per mCi of Tc-99m, and it applies to what the patient receives. Tc-99m decays much faster than Mo-99, so the ratio rises over time.
- Tc-99m left after 6 h: 1,000 × 2^(−6/6.02) ≈ 1,000 × 0.50 = 500 mCi
- Mo-99 left after 6 h: 100 × 2^(−6/66) ≈ 100 × 0.94 = 94 µCi
- Ratio: 94 ÷ 500 ≈ 0.19 µCi/mCi, which is over 0.15
A ignores that the ratio grows. B reverses the trend: Tc-99m loses activity faster, so the Mo-99/Tc-99m ratio rises. C gets the rule backward: the limit is on the material given to the patient.
Sources: 10 CFR 35.204(a)(1); Lantheus TechneLite prescribing information, “Description,” “Physical Characteristics” and “Assay Instructions.”
Question 10
Safety · NRC regulations · NMT-10
Which routine, non-emergency administration requires a written directive under NRC rules?
Show answer and explanation for Question 10 (NMT-10)
Answer: B.
A written directive is required before giving I-131 sodium iodide greater than 30 µCi (1.11 MBq). 50 µCi is over that.
The threshold is specific to I-131 sodium iodide. The I-123 and Tc-99m doses in the other options don't trigger it, however large their millicurie numbers look.
Written directives are also required for any therapeutic dosage of unsealed byproduct material. If delaying for a written directive would jeopardize a patient's health in an emergency, an oral directive is allowed; it must be documented as soon as possible, with a written directive prepared within 48 hours.
Source: 10 CFR 35.40(a), (a)(1) and (b).
Question 11
Safety · NRC regulations · NMT-11
The prescribed dosage for a bone scan is 25 mCi of Tc-99m MDP, with no dosage range given. The syringe measures 19.5 mCi just before injection. The authorized user has given no other direction. Under NRC rules, what should the technologist do?
Show answer and explanation for Question 11 (NMT-11)
Answer: C.
The licensee must determine and record each dosage's activity before medical use. Unless the authorized user directs otherwise, a dosage can't be used if it differs from the prescribed dosage by more than 20%.
(25 − 19.5) ÷ 25 = 5.5 ÷ 25 = 22%, which is over 20%.
B uses the wrong tolerance. A ignores the 20% rule. D records something false.
Activity can be determined by direct measurement or, for a unit dosage, by decay correction from an appropriately licensed supplier's determination. This NRC rule doesn't require every unit dose to be re-measured in your own dose calibrator.
Source: 10 CFR 35.63(a), (b) and (d).
Question 12
Safety · Medical events · NMT-12
Patient A is mistakenly given Patient B's 25 mCi Tc-99m MDP. Patient A's estimated effective dose equivalent is well below 5 rem. The estimated dose to every organ or tissue and the shallow-dose equivalent to the skin are each well below 50 rem. Under 10 CFR 35.3045, is this a reportable medical event?
Show answer and explanation for Question 12 (NMT-12)
Answer: B.
For a wrong-individual administration, 10 CFR 35.3045(a)(1)(ii)(C) requires a resulting dose above at least one of those thresholds. This mix-up doesn't reach them. A dosage difference of 20% or more is evaluated under a separate provision, which also requires a qualifying difference in radiation dose; the percentage alone does not establish a reportable medical event.
That doesn't make it a non-event at work. Your facility's incident reporting, physician notification, and any stricter state rules still apply.
D is wrong because the rule isn't limited to therapy. A diagnostic error that crosses the thresholds would qualify.
Question 13
Safety · Patient release · NMT-13
A breastfeeding patient meets the NRC criteria for release after a radiopharmaceutical administration. Calculations show that, without interruption of breastfeeding, the total effective dose equivalent to her nursing infant could exceed 0.1 rem (1 mSv). What must her release instructions include?
Show answer and explanation for Question 13 (NMT-13)
Answer: D.
A patient can be released if the total effective dose equivalent to any other individual is not likely to exceed 0.5 rem (5 mSv). If that dose to another individual is likely to exceed 0.1 rem (1 mSv), the patient must get instructions, including written instructions, to keep others' doses as low as reasonably achievable. If a nursing infant or child could exceed 0.1 rem without a breastfeeding interruption, those instructions must also cover pausing or stopping breastfeeding and the possible consequences of not following that guidance.
B is wrong because release is allowed up to 0.5 rem. The 0.1 rem level triggers instructions, not a hospital stay.
Source: 10 CFR 35.75(a)–(b).
Image Production
Question 14
Image Production · Gamma camera · NMT-14
A technologist sets a 20% symmetric energy window for Tc-99m, using a 140 keV photopeak. What range of photon energies will the camera accept?
Show answer and explanation for Question 14 (NMT-14)
Answer: A.
A 20% window is 20% of 140 keV, or 28 keV wide, centered on the photopeak:
140 ± 14 = 126–154 keV
B applies 20% to each side, which makes a 40% window. D is a 10% window. The common mistake is applying the percentage to each side instead of the total width.
C is a 20 keV-wide window, approximately 14.3% of 140 keV.
Source: derived calculation. Tc-99m's principal photon is 140.5 keV per the TechneLite prescribing information, “Physical Characteristics,” Table 1; this problem uses 140 keV.
Question 15
Image Production · Collimators · NMT-15
An In-111 imaging study is scheduled. In-111's main photons are about 171 and 245 keV. Which collimator is appropriate?
Show answer and explanation for Question 15 (NMT-15)
Answer: D.
Low-energy collimators have relatively thin septa, the lead walls between the holes. In-111's higher-energy photons cause greater septal penetration with these collimators, degrading image contrast and spatial information. A medium-energy collimator has thicker septa to reduce that penetration.
C is wrong because photon energy, not "diagnostic" use, decides the collimator. Without any collimator (B), the camera can't tell where photons came from.
Sources: Octreoscan prescribing information, “Physical Characteristics,” Table 1; SNM Somatostatin Receptor Scintigraphy 2.0, section VI.D.2, page 319 (medium-energy collimator).
Question 16
Image Production · Quality control · NMT-16
The collimator is removed from a gamma camera, and a flood image is acquired with uniform irradiation to see how evenly the detector responds across its field. Which property is being tested?
Show answer and explanation for Question 16 (NMT-16)
Answer: A.
Intrinsic uniformity is the detector's own uniformity, tested without a collimator. System uniformity (B) is tested with the collimator on, so it also catches collimator damage.
Energy resolution (C) is how well the camera separates photon energies. Spatial resolution (D) is how well it separates nearby points. An even flood answers neither of those.
Source: IAEA, Quality Assurance for SPECT Systems (Human Health Series No. 6, 2009), section 2.1.5 and sections 2.1.6.1–3, printed pages 30–34.
Question 17
Image Production · Dose calibrator · NMT-17
For a Mo-99 breakthrough assay, the eluate vial is put inside the manufacturer-specified lead Mo-99 assay canister before it is measured in the dose calibrator. Why?
Show answer and explanation for Question 17 (NMT-17)
Answer: A.
The assay uses the difference in photon energies. The canister strongly attenuates Tc-99m's approximately 140 keV radiation while allowing a measurable contribution from higher-energy Mo-99 radiation. An ionization-chamber dose calibrator measures the resulting ionization signal; its specified assay setting and correction are used to determine Mo-99 activity.
D is a separate chemical test. Aluminum breakthrough is checked with a color indicator, with a limit of 10 µg per mL of eluate. Neither B nor C identifies the purpose of this selective assay.
Sources: TechneLite prescribing information, “Assay Instructions,” “Radiometric Molybdenum Test Procedure,” and aluminum ion test; Mirion Moly Assay Canister, “Description.”
Question 18
Image Production · PET · NMT-18
How does a PET scanner detect F-18 FDG?
Show answer and explanation for Question 18 (NMT-18)
Answer: C.
F-18 decays by positron emission. Each positron meets an electron and annihilates, producing two 511 keV photons that travel in nearly opposite directions. The scanner records an event when opposing detectors register photons within a short timing window. That's coincidence detection, and it needs no physical collimator.
The PET image signal comes from the annihilation photons, not from direct detection of the emitted positrons or other beta particles (B, D).
Source: SNMMI/ACNM Guideline for the Use of Radiopharmaceuticals 5.0, section II.B, pages 3–4.
Procedures
Question 19
Procedures · Radionuclides and radiopharmaceuticals · NMT-19
A unit dose of Tc-99m sestamibi measures 30 mCi at 07:00. The patient is injected at 13:00. About how much activity is left? Use a Tc-99m half-life of 6 hours.
Show answer and explanation for Question 19 (NMT-19)
Answer: B.
Six hours is one half-life: 30 × ½ = 15 mCi.
The general formula is A = A₀ × (½)^(t ÷ T½). At 12 hours, which is two half-lives, the activity would be 7.5 mCi (A).
Neither 10 mCi (C) nor 25 mCi (D) represents one halving of 30 mCi.
Source: TechneLite prescribing information, “Physical Characteristics” (half-life 6.02 h; about 50% left at 6 h). Calculation derived using the six-hour assumption in the question.
Question 20
Procedures · Radiopharmaceutical preparation · NMT-20
A Technescan MAG3 kit is prepared, and its radiochemical purity test shows 85%. What should the technologist do?
Show answer and explanation for Question 20 (NMT-20)
Answer: B.
Radiochemical purity is the share of the radioactivity that is in the intended chemical form. The Technescan MAG3 labeling requires a purity check before use and says a preparation below 90% must not be used.
Increasing the activity would not correct the failed purity result and would administer additional impurities. D bypasses the required purity verification. The label includes a 10-minute boiling-water-bath step in initial preparation; it does not authorize the proposed use of a failed preparation without retesting.
Source: Technescan MAG3 prescribing information, “Instructions for Preparation,” Procedure steps 6 and 9.
Question 21
Procedures · Gastrointestinal and genitourinary · NMT-21
Which pairing correctly describes how the kidneys mainly handle these tracers?
Show answer and explanation for Question 21 (NMT-21)
Answer: B.
MAG3 is mostly removed from the blood by transporters in the proximal tubules. Its extraction fraction is 40–50%, more than twice DTPA's. DTPA is cleared purely by glomerular filtration, so it can be used to estimate glomerular filtration rate (GFR).
A reverses the pair. C ignores MAG3's main route. D describes a cortical agent such as DMSA, not these dynamic renal tracers.
Source: SNMMI/EANM guideline for diuretic renal scintigraphy in adults (2018), sections VII.A and VII.D.
Question 22
Procedures · Other imaging (lung) · NMT-22
A patient with known severe pulmonary hypertension is referred for a perfusion lung scan with Tc-99m MAA. What does the PULMOTECH MAA labeling say about this patient's severe pulmonary hypertension?
Show answer and explanation for Question 22 (NMT-22)
Answer: A.
MAA particles work by lodging in the lung's small arterioles and capillaries. That's exactly why they're a risk when the pulmonary circulation is already compromised. The labeling lists severe pulmonary hypertension as a contraindication. It also calls for the lowest possible particle number in pulmonary hypertension and in right-to-left heart shunts. That particle-reduction guidance does not remove the labeled contraindication in severe pulmonary hypertension.
The usual adult range is 200,000–700,000 particles per injection. C is wrong because the vial is mixed by gentle inversion, not shaking. The technologist flags this case to the supervising physician rather than proceeding.
Source: PULMOTECH MAA prescribing information, revised October 2025, sections 2.3, 2.6, 4, 5.1, 5.3 and 12.1.
Question 23
Procedures · Other imaging (bone) · NMT-23
In a three-phase bone scan, which phase is a dynamic series of images taken while the radiopharmaceutical is being injected?
Show answer and explanation for Question 23 (NMT-23)
Answer: C.
Phase 1, the flow phase, captures tracer arriving in the area during injection. The blood-pool phase (A) comes right after, within about 10 minutes. The delayed skeletal phase (B) is usually 2–4 hours later. A 24-hour image (D) is optional.
If you miss the flow acquisition, you can't get it back later. The tracer has already arrived.
Source: SNMMI Practice Guideline for Bone Scintigraphy 4.0, section III, pages 4–5, and section VI.D, pages 9–10.
Question 24
Procedures · Other imaging (bone) · NMT-24
Between a Tc-99m MDP injection and delayed whole-body bone imaging, what should the patient be told?
Show answer and explanation for Question 24 (NMT-24)
Answer: A.
Drinking water and urinating often clear tracer from soft tissue faster. That improves bone-to-background contrast and lowers the radiation dose to the bladder. Emptying the bladder right before imaging also keeps bladder activity from hiding the pelvis.
Routine delayed images are taken 2–4 hours after injection. 24-hour images (C) are optional.
Source: SNMMI Practice Guideline for Bone Scintigraphy 4.0, section VI.B.1, page 7, and section VI.D.3, pages 9–10.
Question 25
Procedures · Gastrointestinal and genitourinary · NMT-25
An adult solid-meal gastric emptying study follows the standardized low-fat Tc-99m sulfur-colloid egg-white meal protocol, with the complete meal consumed. Gastric retention is 18% at 4 hours. How is this result classified?
Show answer and explanation for Question 25 (NMT-25)
Answer: B.
Under the consensus protocol, more than 10% retention at 4 hours means delayed gastric emptying. The other delayed cutoffs are more than 90% at 1 hour and more than 60% at 2 hours. Rapid emptying is less than 30% retention at 1 hour.
The standard protocol images at 0, 1, 2 and 4 hours. No 6-hour image is needed (D).
Source: Abell et al., Consensus Recommendations for Gastric Emptying Scintigraphy, J Nucl Med Technol 2008;36:44–54, Table 1, page 47, and Appendix 1 (standardized meal and acquisition protocol).
Question 26
Procedures · Gastrointestinal and genitourinary · NMT-26
During hepatobiliary imaging, sincalide is infused at 0.02 µg/kg over 60 minutes. The gallbladder ejection fraction (GBEF), measured at 60 minutes, is 25%. How should this be read?
Show answer and explanation for Question 26 (NMT-26)
Answer: D.
For 0.02 µg/kg sincalide infused over 60 minutes, the SNM guideline gives a reference GBEF of at least 38%. A measured GBEF of 25% is below that method-specific reference range.
Normal values depend on the infusion method, so the 20% cutoff and the proposed one-minute bolus do not apply here. Gallbladder visualization alone does not establish normal gallbladder emptying.
Source: SNM Practice Guideline for Hepatobiliary Scintigraphy 4.0, J Nucl Med Technol 2010;38:210–218, section VI.E.3, page 213.
Question 27
Procedures · Cardiac · NMT-27
On a planar gated blood-pool study (MUGA), the background-corrected left ventricular counts are 12,000 at end-diastole and 5,400 at end-systole. What is the left ventricular ejection fraction (LVEF)?
Show answer and explanation for Question 27 (NMT-27)
Answer: A.
LVEF = (end-diastolic counts − end-systolic counts) ÷ end-diastolic counts × 100
(12,000 − 5,400) ÷ 12,000 × 100 = 6,600 ÷ 12,000 × 100 = 55%
B is end-systolic counts divided by end-diastolic counts, which is the share left behind, not ejected. D divides by end-systolic counts. The denominator is always end-diastolic counts, the fullest the ventricle gets. Both counts must be background-corrected, or the result will be off.
Source: SNMMI/EANM guideline for gated equilibrium radionuclide angiography, J Nucl Med Technol 2020;48:126, section V, equation 1.
Question 28
Procedures · Cardiac (amyloid imaging) · NMT-28
A Tc-99m pyrophosphate (PYP) study for suspected transthyretin (ATTR) cardiac amyloidosis shows diffuse myocardial uptake confirmed on SPECT, with uptake equal to the ribs (visual grade 2) and no significant blood-pool activity. The heart-to-contralateral-lung (H/CL) ratio is 1.6 at 1 hour. What else must be done before the result supports an ATTR diagnosis?
Show answer and explanation for Question 28 (NMT-28)
Answer: B.
Grade 2 or 3 myocardial uptake supports ATTR cardiac amyloidosis only after a monoclonal process has been excluded. The H/CL ratio must not be used to confirm or refute the diagnosis. AL amyloidosis can also take up PYP. ASNC advises serum and urine immunofixation and serum free light chains in every patient, whatever the scan shows.
If excess blood-pool activity prevents interpretation at 1 hour, repeat SPECT imaging at 3 hours is recommended. A routine 24-hour repeat (C) and a stress perfusion study (D) do not replace the evaluation for AL amyloidosis.
Source: ASNC, Interpretation and Reporting of Cardiac Scintigraphy with Bone-Avid Tracers in Suspected Transthyretin Cardiac Amyloidosis, printed pages 1–4 and 6.
Question 29
Procedures · Endocrine and oncology · NMT-29
A patient scheduled for an F-18 FDG oncology PET/CT ate breakfast 1 hour ago. What is the most appropriate action?
Show answer and explanation for Question 29 (NMT-29)
Answer: D.
A recent meal can alter glucose and insulin levels and change FDG distribution, including increased uptake in insulin-sensitive tissues. The PETNET label calls for a 4–6-hour fast before oncology FDG injection. The EANM/SNMMI guideline also requires glucose measurement before administration.
Giving insulin immediately before FDG is not a fix for inadequate preparation: it can increase muscle uptake. Insulin use and examination timing require the department's patient-specific protocol. During the uptake period, the patient remains seated or lying quietly to limit muscle uptake.
FDG uptake also isn't specific to cancer. Inflammation and infection can take it up too.
Sources: PETNET Fludeoxyglucose F 18 prescribing information, revised March 2026, sections 2.3, 5.2, 12.2 and 14.1; EANM/SNMMI FDG PET/CT tumour imaging guideline, version 2.0 (2015), “Patient preparation,” journal pages 332–334.
Question 30
Procedures · Endocrine and oncology · NMT-30
Exam-version note: In-111 pentetreotide is named in Attachment A for examinations through January 31, 2027, but is not named in the list effective February 1, 2027. This question is retained as a current-list example; the list change does not establish a clinical restriction or guarantee that the principle cannot be tested.
A patient on octreotide therapy is scheduled for In-111 pentetreotide imaging. Why does the labeling suggest considering a temporary pause in octreotide?
Show answer and explanation for Question 30 (NMT-30)
Answer: A.
Pentetreotide images somatostatin receptors. Unlabeled octreotide competes for the same receptors. So the labeling advises considering a temporary pause, with monitoring for withdrawal symptoms. That decision belongs to the ordering physician.
The label also recommends a mild laxative starting the evening before to reduce bowel activity. The reason for considering a pause is receptor competition, not a change in In-111's physical half-life (C).
Sources: Octreoscan prescribing information, “Warnings” and “Dosage and Administration”; ARRT Attachment A in the current and February 2027 specifications, page 11.
Question 31
Procedures · Endocrine and oncology (therapy) · NMT-31
A patient is receiving Lu-177 dotatate. Why is an amino acid solution containing L-lysine and L-arginine started 30 minutes before the infusion?
Show answer and explanation for Question 31 (NMT-31)
Answer: C.
The amino acids compete for reabsorption in the proximal tubules, which lowers the radiation dose to the kidneys. The infusion starts 30 minutes before Lu-177 dotatate and continues during it and for at least 3 hours afterward.
Preventing nausea is a separate supportive-care step: the label directs administration of antiemetics before the amino acid solution. A and D describe tumor targeting; the amino acid infusion is given for kidney protection.
Source: Lutathera US prescribing information, revised October 2024, sections 2.3 and 5.4.
After the questions
After answering all 31 questions, count your result as "X of 31 correct." If you stop early, report "X correct out of Y attempted" instead. That number tells you how you did on these questions, nothing more. The set is a starter sample. It covers all four categories but isn't weighted like the real exam, which is about 59% procedures, and it doesn't cover every procedure in the outline.
Take each miss to the error log and the matching week of the study plan.
Calculations to know cold
These come up across categories, and the exam's on-screen calculator won't help if you set the problem up wrong. The worked values are study examples, not patient prescriptions; the decay-and-volume example assumes a homogeneous sample with unchanged volume and no additions or withdrawals.
| Calculation | Formula | Worked example |
|---|---|---|
| Decay | A = A₀ × (½)^(t ÷ T½) | 30 mCi Tc-99m, 6 h later → 15 mCi |
| Decay and volume | Volume = activity needed ÷ concentration at the same time | 400 MBq/mL at 08:00, T½ 6 h. At 20:00 it's 100 MBq/mL, so 100 MBq is 1 mL. Using the 08:00 concentration gives the wrong 0.25 mL. |
| Mo-99 ratio at injection | (Mo-99 µCi now) ÷ (Tc-99m mCi now) | 0.10 at elution → about 0.19 six hours later, which fails the 0.15 limit |
| Dosage deviation (%) | abs(measured − prescribed) ÷ prescribed × 100 | 25 mCi prescribed, 19.5 measured → 22%, over the 20% limit |
| Effective half-life | T_eff = (T_p × T_b) ÷ (T_p + T_b), for independent exponential losses | 6 h and 3 h → 2 h |
| Inverse square | I₂ = I₁ × (d₁ ÷ d₂)² | 8 mR/h at 1 m → 2 mR/h at 2 m |
| Energy window | Width = % × photopeak; range = peak ± half the width | 20% at 140 keV → 126–154 keV |
| LVEF | (ED − ES) ÷ ED × 100, background-corrected | 12,000 and 5,400 counts → 55% |
| Units | 1 mCi = 37 MBq; 1 rem = 10 mSv | 200 mCi = 7.4 GBq |
A useful habit: write the units you want in the answer before you pick a formula. For anything that decays, correct for time first, then do the rest. The calculation sources are beside the related questions; the unit conversions follow 10 CFR 20.1004 and 20.1005.
Where the points are
Testing on or after February 1, 2027? Use the right-hand column below — ARRT's updated outline starts that day.
ARRT's Nuclear Medicine Technology (N) exam has 200 scored questions. This is how they split.
| Category | Exams through Jan. 31, 2027 | Exams from Feb. 1, 2027 |
|---|---|---|
| Procedures | 118 (59%) | 117 (58.5%) |
| Image Production (instrumentation) | 33 (16.5%) | 30 (15%) |
| Safety (physics, radiobiology, regulations) | 25 (12.5%) | 27 (13.5%) |
| Patient Care | 24 (12%) | 26 (13%) |
More than half the exam is procedures. Give that material substantial review, then adjust your time around the concepts you cannot yet explain. Safety is small but full of rules and math you can lock down with practice. Sources: ARRT content specifications through January 31, 2027 and from February 1, 2027, page 1. Percentages are each count divided by 200.
Your 8-week study plan
This plan assumes about 8–10 hours a week. It's built for someone who has finished, or nearly finished, an ARRT-verified nuclear medicine program. It's our editorial plan, not ARRT's, and no number of hours guarantees a result. The plan includes every category; give extra time to the gaps in your own knowledge. Safety math comes early because those skills show up in every category.
Keep the content specification PDF for your exam date open the whole time. Its topic list is your checklist.
| Week | Learn | Practice | Review |
|---|---|---|---|
| 1 · Safety: rules and math | NRC dose limits, written directives, dosage tolerance, medical events, patient release, Mo-99 and Sr limits | Questions 5–13. Rework every calculation in the table above without looking. | Start your error log. Mark each Safety topic in the outline as can explain, shaky, or new. |
| 2 · Safety and Patient Care | Biological effects, area monitoring, package receipt, spills, storage and disposal. Ethics, communication, patient monitoring, emergencies, infection control, hazardous materials, pharmacology. | Questions 1–4. For each patient-care topic, say out loud why the step matters, not just what it is. | Redo any Week 1 miss without notes. |
| 3 · Image Production | Survey meter, dose calibrator, scintillation detectors, gas and aerosol delivery, gamma camera and collimators, QC, SPECT, PET/CT, data processing, informatics | Questions 14–18. For each QC test, name what it checks and one thing it can't tell you. | Error log review. Re-explain any concept you missed twice. |
| 4 · Radionuclides and radiopharmaceuticals | Production (generator, cyclotron, reactor), generator QC, kit preparation, radiochemical purity, localization mechanisms, administration | Questions 9, 19–22. Go through Attachment A one agent at a time: what it is, how it localizes, what the study shows. | Mixed redo of Weeks 1–3 misses. |
| 5 · Cardiac | Exercise and pharmacologic stress and their contraindications, perfusion agents, gated blood pool, viability, amyloid imaging | Questions 3, 4, 27, 28. Calculate LVEF from your own made-up counts. | Error log review. |
| 6 · Endocrine and oncology | Thyroid and parathyroid, tumor imaging including PET, neuroendocrine imaging, therapy patient prep and release | Questions 10, 13, 29–31 | Redo the Safety rules from Week 1 cold. |
| 7 · GI/GU and other imaging | Gastric emptying, hepatobiliary, GI bleeding, renal studies. Bone, brain, lung, infection, lymphoscintigraphy. | Questions 21–26. For each study, write one line each for prep, agent and route, imaging start time, views, and what would ruin it. | Error log review. |
| 8 · Put it together | Fill gaps: go back through the outline and find any topic still marked shaky or new | Redo all 31 questions without opening explanations. Then use any full-length practice from your program, timed at about 1 minute per question. | Final error log pass. Confirm your appointment details in Pearson's confirmation and review the ARRT handbook. |
If you have 4 weeks: doing two plan weeks per calendar week preserves the original workload at about 16–20 hours a week. If that is not realistic, prioritize unresolved concepts from the outline while keeping practice and review in the plan.
If you're retaking: use your ARRT score report to see which categories were relatively weak, and give them extra time. Keep all four categories in the plan. Small differences between section scores aren't precise enough to ignore a category.
If you don't know your exam date yet: start with Weeks 1–4. That material changes little between the two outlines. Pick the version-specific details once you book.
If you test on or after February 1, 2027: use the replacement outline to check the added Patient Care and Safety material, revised informatics, and procedure groupings. Use that version of Attachment A for agent-specific review; Question 30 is labeled as a current-list example. Adjust study time to your gaps rather than converting each question-count change into a fixed number of hours.
Turn misses into your next session
Re-reading the right answer feels productive, but it doesn't fix the reasoning that picked the wrong one. Log each miss, and each lucky guess, like this:
| Question | My answer | Correct | What I misunderstood | Why the wrong answer looked right | Source to reread | Redo task |
|---|---|---|---|---|---|---|
| 7 (example) | 4 mR/h | 2 mR/h | Used inverse distance, not inverse square | Doubling distance felt like it should halve the rate | Inverse square explanation, Question 7 | Recalculate at 3 m and 4 m from 8 mR/h at 1 m |
| Blank row for your next miss |
Come back to every row within a week and do the redo task without looking.
What changes on February 1, 2027
Your exam date decides which outline applies, not when you applied or graduated. ARRT says you don't need to reschedule. Just study the outline for your date.
What stays the same: 200 scored questions, 30 unscored pilot questions, and the same four categories.
What changes, from ARRT's announcement:
- Patient Care adds medical equipment malfunctions, patient comfort and modesty, and communicating critical findings to the care team. Pharmacology adds local effects (such as infiltration) and emergency medications.
- Safety adds short-term versus long-term exposure under biological effects of radiation.
- Image Production updates the informatics section. The 2027 outline lists downtime procedures there.
- Procedures drops sequestration and radiochromatography from the radionuclides and radiopharmaceuticals section. Neuroendocrine and adrenal imaging move from the endocrine section to the tumor section.
What we found comparing the two PDFs:
- The bone section no longer lists PET/CT.
- Attachment A, the list of pharmaceuticals, has its own version in each outline. Use the one for your date.
Passing standard: ARRT has also set an updated passing standard for exams taken on or after February 1, 2027. The reported passing score stays at 75. ARRT says the change isn't meant to make the exam easier or harder.
CT on this exam: both outlines say diagnostic CT isn't tested. Both limit CT to attenuation correction and anatomic localization. The 2027 outline lists CT operating principles, quality control and image acquisition under Image Production.
Procedures subcategories (scored questions):
| Subcategory | Through Jan. 31, 2027 | From Feb. 1, 2027 |
|---|---|---|
| Radionuclides and radiopharmaceuticals | 28 | 28 |
| Cardiac | 25 | 25 |
| Endocrine and oncology | 25 | 24 |
| Gastrointestinal and genitourinary | 18 | 20 |
| Other imaging | 22 | 20 |
| Procedures total | 118 | 117 |
Sources: ARRT, "Updated Nuclear Medicine Technology Documents" (April 1, 2026); ARRT, updated passing standard for nuclear medicine technology (October 19, 2026); both content specifications linked above.
Exam at a glance
| Exam fact | Detail |
|---|---|
| Questions | 230 total: 200 scored and 30 unscored pilot questions. You can't tell which are pilot. |
| Test time | 230 minutes (3 hours 50 minutes), about 1 minute per question |
| Appointment | 250 minutes (4 hours 10 minutes), including tutorial, nondisclosure agreement and survey |
| Passing score | Scaled score of 75 on a 1–99 scale. It isn't 75% correct. |
| Question types | Mostly single-best-answer multiple choice. Some ask you to pick several answers, sort steps into order, select an image, or answer after a short video. |
| Calculator | Basic and scientific on-screen calculators. You can't bring your own. |
| Attempts | Three attempts within three years of your first exam window opening |
| Exam window | One year (365 days) once ARRT opens it |
| Application fee | $225 for the primary pathway |
| Units | Both SI and conventional units appear |
Sources: ARRT 2026 Primary Eligibility Pathway Handbook, pages 7, 14, 30, 37, 40, 43 and 53–54; ARRT application fees; ARRT, updated passing standard.
Quick answers
Is ARRT the same as NMTCB?
No. They're separate organizations with separate exams. ARRT's credential is R.T.(N)(ARRT). The Nuclear Medicine Technology Certification Board's is CNMT. This page covers only the ARRT exam. For the other path, see NMTCB exams. Employers and states may accept one or both, so check the specific requirement.
Do I need a degree?
Yes. ARRT requires an associate degree or higher, in any subject, from an institution accredited by an agency ARRT recognizes. The degree must be conferred before you test. You also need to complete an ARRT-verified nuclear medicine program. See the ARRT credential page.
Does passing let me work in any state?
Not automatically. ARRT certification and state permission to practice are separate. Check ARRT's state licensing overview and your state's agency.
How do I register, and what if I don't pass?
You apply to ARRT, then schedule with Pearson 24 hours after receiving your Candidate Status Report. Your appointment must fall within your exam window, after your program is complete and your degree is conferred. See the ARRT candidate handbook, pages 30–31, and Pearson's ARRT scheduling page. Retake rules: ARRT exam retake policy. To read your score report: ARRT exam results.
What about after I pass?
ARRT credentials require ongoing continuing education. See ARRT continuing education requirements.
Sources
Exam facts
- ARRT Nuclear Medicine Technology credential page
- Content specifications, valid through January 31, 2027
- Content specifications, effective February 1, 2027
- ARRT 2026 Primary Eligibility Pathway Handbook
- ARRT news: updated nuclear medicine documents and updated passing standard
- ARRT application fees
Teaching sources
- Regulations: 10 CFR Part 20 and Part 35. Each regulatory question links to its exact section.
- Identification and infection control: The Joint Commission two-identifier requirements; CDC hand hygiene.
- Physics and instrumentation: IAEA SPECT quality assurance; IAEA point-source geometry, section 2.4.3; IAEA effective-half-life equation, section 12.4; SNMMI/ACNM radiopharmaceutical guideline 5.0, section II.B; Mirion Mo-99 assay canister.
- Prescribing information:
- Guidelines:
- SNMMI bone scintigraphy 4.0
- SNMMI/EANM diuretic renal scintigraphy
- SNMMI/EANM gated ERNA
- Gastric emptying consensus
- SNM hepatobiliary scintigraphy 4.0
- EANM/SNMMI FDG PET/CT tumour imaging, version 2.0 (2015)
- SNM somatostatin receptor scintigraphy 2.0
- ASNC interpretation and reporting of cardiac scintigraphy with bone-avid tracers
Last verified: October 27, 2026. The Castleport Test Prep Editorial Team checked the exam format, scoring, fee, both content specifications, the February 2027 changes and passing standard, and every regulation, label and guideline cited in the questions against the sources above. The practice questions are original and source-checked. They have not been reviewed by a licensed nuclear medicine professional.
Castleport Test Prep is an independent exam prep publisher. We are not affiliated with, endorsed by, or approved by the American Registry of Radiologic Technologists (ARRT) or the Nuclear Medicine Technology Certification Board (NMTCB). Exam and credential names are used only to identify their subjects, and trademarks belong to their respective owners. The practice questions on this page are original and unofficial, not actual exam questions. Using this page doesn't guarantee an exam result, certification or licensure.