Procedures: Radionuclides and Radiopharmaceuticals (14%)

ARRT-N · 42 questions

• A technologist draws a Tc-99m sestamibi dose for a resting perfusion study. The vial label lists the drug name, activity, volume, and expiration time, and a tungsten syringe shield sits ready on the cart. Department policy requires the patient's identity and every label field checked against the order while the syringe stays shielded. Which verification and handling step must be completed before the syringe leaves the dosing area?
• A patient is referred for parathyroid scintigraphy with Tc-99m sestamibi. The dosimetry summary states that the urinary bladder wall receives the highest absorbed dose of any organ, while the parathyroid tissue supplies the diagnostic image. How should the team classify the target organ and the critical organ for this study?
• During quality control in a hospital radiopharmacy, one result shows that a freshly eluted Tc-99m generator sample is within its molybdenum breakthrough limit, and a second shows that a sulfur colloid preparation contains no free pertechnetate. Which type of purity does each result verify?
• A technologist draws a Tc-99m dose that reads 800 MBq at 7:00 AM for a patient booked at 1:00 PM, and the appointment slips to 7:00 PM with no fresh dose available. The same syringe will be used, and the department logs the activity at administration. What activity should be documented when the patient is injected at 7:00 PM?
• A community hospital wants F-18 FDG PET for 8:00 AM weekday patients but cannot buy a cyclotron, and the nearest producer is two hours away by road. F-18 has a half-life of about 110 minutes. Which supply plan fits this schedule?
• A department prepares the same technetium-99m kit throughout the day, adjusting each draw for decay so every kit receives the target activity. Batches made late in the afternoon label less efficiently than morning batches, although all draws come from the same eluate held since the morning and eluate pH, incubation temperature, and incubation time stay within the package insert ranges. Which remaining preparation variable best explains the drop in labeling efficiency?
• A colleague has just drawn a Tc-99m sestamibi dose for an outpatient myocardial perfusion study, and the syringe sits unshielded on the counter while the activity is recorded. Verify the patient, radiopharmaceutical, and prescribed activity against the written order; also confirm the labeled activity’s calibration time and the drawn volume. Hand exposure must stay low. Which plan meets both requirements?
• A patient two minutes into a slow intravenous radiopharmaceutical injection develops widespread hives, audible wheeze, and throat tightness while the syringe is still connected. The emergency drugs are in the adjacent room and the technologist is alone at the bedside. Which immediate action best manages this administration reaction?
• A quality check on a freshly prepared Tc-99m kit shows more free pertechnetate than the package insert allows. The eluate was drawn within its labeled time and used within its stated stability period, the kit vial was stored as labeled and is in date, and the first dose was drawn only after the full incubation period. Which preparation condition most likely accounts for the excess free pertechnetate?
• A clear, solution-type technetium-99m preparation for a renal study appears free of visible matter under backlighting, yet chromatography on the same vial produces a large free pertechnetate peak. The release decision hinges on one quality control measurement for this batch. Which quality control result determines whether this vial is released to the clinic?
• A radiopharmacy checks a Mo-99/Tc-99m generator eluate against its release sheet: aluminum ions and pH are within limits, radiochemical purity of pertechnetate exceeds 95%, and 99.9% of the activity is Tc-99m. Which purity aspect does the 99.9% figure describe for this eluate?
• During morning dose preparation, a bone imaging referral arrives for an adult with a known prostate primary being staged for osseous spread. The tracer must settle onto calcium phosphate mineral where new bone is being formed, and it must come from a generator-eluted kit. Which radiopharmaceutical's localization mechanism matches this study?
• During a myocardial perfusion study, an adult outpatient who reports fainting with past blood draws becomes pale, clammy, and lightheaded a few minutes after a radiopharmaceutical injection through a peripheral IV, and the pulse is slow. Which immediate intervention best reverses the mechanism behind this injection reaction?
• A patient with biopsy-proven cirrhosis is scheduled for a liver-spleen scintigram ordered to evaluate reticuloendothelial function. Before drawing up the dose, the technologist confirms why the ordered agent accumulates in the liver. Which localization mechanism accounts for this agent's liver uptake?
• Tc-99m sulfur colloid for a liver-spleen study passes chromatography for radiochemical purity and passes visual inspection, yet the measured particle size falls outside the stated range. Why does the particle size result alone make this preparation unusable?
• A cardiac PET program performs rest and stress myocardial perfusion imaging during one visit, with the stress injection about half an hour after the rest injection. The perfusion agent is rubidium-82, a positron emitter with a physical half-life of roughly 75 seconds. Which production method supplies a usable dose for both injections?
• At 8:00 AM the dose calibrator shows a Tc-99m radiopharmaceutical vial containing 800 MBq in 4.0 mL. The prescription calls for 200 MBq to be injected at 2:00 PM, and Tc-99m has a physical half-life of about six hours. Which syringe volume drawn at 2:00 PM delivers the ordered activity?
• A patient asks how long the injected tracer will keep decaying after the appointment, and the team notes a 6-hour physical half-life with a 12-hour biological half-life for this agent. Which value best estimates how fast the total activity in the patient falls?
• A technologist is drawing an afternoon Tc-99m sestamibi dose for a patient on the stress table. Policy requires the full label checked against the written order, the patient positively identified, and hand dose kept as low as possible during handling. Which dose-handling practice meets the label, identification, and shielding rules?
• A resident asks how fast a tracer leaves the body when its physical half-life is 8 hours and its whole-body biological half-life is 24 hours. Which value should you report as the time for the body's total activity to fall by half?
• Routine quality control on a technetium-99m generator eluate shows molybdenum-99 activity above the permitted level for the amount of technetium-99m present, so the vial is set aside before any dose is drawn. Which explanation correctly identifies the kind of purity failure the eluate has?
• A patient is referred for whole-body bone scintigraphy with Tc-99m MDP because metastatic disease is suspected. The radiopharmacist notes that the agent binds to bone while unbound activity travels through the kidneys into urine over the next few hours. Which statement correctly identifies the study's target organ and its critical organ?
• A hospital with no cyclotron or reactor schedules an ordered technetium-99m sestamibi SPECT study with the first patient at 07:00, while its only isotope delivery arrives between 09:00 and 11:00. Which supply arrangement can dose the first patient on time?
• A liver and spleen study requires 185 MBq of technetium-99m sulfur colloid. The unit-dose syringe is calibrated for 12:00 PM and holds 925 MBq in 5.0 mL, a concentration of 185 MBq per milliliter at noon. The appointment moves to 6:00 PM, and the full 185 MBq must be in the syringe at injection. Using technetium-99m's six-hour physical half-life, what volume should be drawn at 6:00 PM to deliver the prescribed activity?
• During an outpatient visit, a dose is pushed through an existing catheter when the patient reports sharp pain and the site blanches and swells; some drug has entered the tissue, the syringe still holds the rest, and department policy requires physician assessment before the patient leaves. Which immediate response best limits tissue damage from this infiltration?
• On a busy afternoon, a technologist reconstitutes a lyophilized kit with freshly drawn eluate for a liver-spleen study. The package insert specifies the holding conditions, quality control includes a chemical check, and the doses must go out before the evening schedule fills. Which preparation verification must be completed before any dose from this kit is released to a patient?
• A 48-year-old with primary hyperparathyroidism is scheduled for a two-phase neck study this afternoon. The protocol calls for a lipophilic cation that diffuses into mitochondria-rich cells and clears from normal thyroid faster than it clears from an adenoma. Which radiopharmaceutical matches that localization mechanism?
• Two patients are scheduled this morning for the same perfusion study, and a shielded unit dose was drawn at the calibrator forty minutes ago before you reached the suite. Before you enter the patient's room, which label details must you confirm to complete the unit dose verification?
• A radiopharmacy reviews a stock radionuclide solution before releasing it for kit preparation. Assay activity, sterility and pH all pass, and the reviewer still must document that the radioactivity is the intended nuclide. Which measurement establishes radionuclidic purity for this release?
• During a protocol in-service, a student argues that the organ showing the greatest uptake on a bone scan must also be the organ receiving the highest radiation dose. The agent in question shows strong cortical bone uptake, yet a sizable fraction is cleared by the kidneys and dwells in the bladder until the patient voids. Which statement correctly distinguishes the target organ from the critical organ for this agent?
• The insert for a reconstituted Tc-99m kit requires eluate pH within a stated range, incubation at a set temperature and time, and a label carrying preparation and expiration times. USP <825> also requires applicable radiopharmaceutical identification and activity information on the label. The pH strip reads at the edge of the range. Which preparation sequence satisfies the insert and USP <825> before the vial is released?
• Indium-111 oxine-labeled autologous white blood cells are reinjected for a patient being evaluated for a suspected deep abdominal abscess, with imaging about a day later. Which mechanism carries the activity to the infected focus and causes it to accumulate there?
• A medical physicist is reviewing a dosimetry worksheet for a patient with reduced renal clearance, where the tracer is cleared more slowly than in a healthy adult. The worksheet lists the physical half-life and the biological half-life separately, and the physician needs the effective value that reflects both processes. Which statement correctly compares physical, biological and effective half-life for this patient?
• A hospital PET service plans a new tracer that decays by positron emission, has a half-life near two hours, and has a parent nuclide that would decay away before it could be stored. The tracer must be produced on site for a same-morning injection. Which production route best fits this tracer?
• During a slow IV infusion of a radiopharmaceutical, a middle-aged patient develops flushing, hives, and itching about halfway through the dose. The IV line is patent and must stay usable for emergency medication, and unit policy requires the physician to be told at once. Which immediate action correctly manages this acute reaction?
• A hospital radiopharmacy prepares a Tc-99m albumin aggregate suspension for an adult lung perfusion study. Free pertechnetate would leave the lung field and collect in the stomach, thyroid, and salivary glands, so the supervisor wants the tracer's chemical form confirmed before release. Which quality control test verifies that the activity is bound to the aggregates?
• A radiopharmacy director is comparing three supply routes before signing a new contract: a nuclear reactor, a medical cyclotron, and a generator column. The director wants each route matched to the physical process that actually creates the nuclide. Which statement accurately compares all three production routes?
• A fresh kit of a particulate radiopharmaceutical has just been prepared for a patient booked in the next room. The prep log shows only the time since reconstitution and a note that the vial looks clear. Which release checks should be documented?
• A Tc-99m kit holds 3,700 MBq (100 mCi) in 10.0 mL at its 8:00 calibration time. A bone scan patient is injected at 14:00, and the order specifies 740 MBq (20 mCi) at injection time, with plenty of kit volume left to draw from. What volume must be drawn at 14:00 to deliver the ordered activity?
• A myocardial perfusion tracer concentrates in the heart for imaging and is cleared through the bowel. For this agent, dosimetry shows that the bowel wall receives the highest absorbed dose of any organ. Which organ is the critical organ, and what makes it so?
• A radiopharmaceutical is cleared by the kidneys so quickly that its biological half-life is only a fraction of its physical half-life. Two colleagues are discussing how long the activity actually stays in the patient, and they disagree about how the three half-lives relate. Which statement correctly compares physical, biological, and effective half-life for this tracer?
• After eluting the Tc-99m generator for the afternoon clinic, the technologist runs the routine dose-calibrator check and finds the molybdenum-99 reading above the allowed limit for that eluate. The radiopharmacist pulls the vial and asks the staff to name the product-quality attribute that failed and what it means for the patient. Which statement correctly identifies the failed attribute and its clinical effect?