NucMed Flashcards
What length of time should a lactating female who undergoes 18F-FDG PET scanning wait before resuming breast-feeding?
(a)4 h
(b) 24 h
(c) 1 week
(d) Breast-feeding should be discontinued
(b) With a physical half-life of 109 min and a biologic half-life of 6 h, the effective half-life for 18F is approximately 1.4 h. Nonetheless, many imaging departments recommend that nursing mothers refrain from nursing for 24 h following a PET study with this isotope, although this varies greatly among labs. Some laboratories recommend as little as 6-h interruption after imaging, so it is completely eliminated from the body in 14 h.
Why is it important to know if a patient has an inflammatory condition before performing an 18F-FDG PET scan?
(a)18F-FDG and certain anti-inflammatory medications cause severe reactions when used simultaneously
(b) 18F-FDG can exacerbate inflammatory conditions
(c) Some inflammatory conditions cause areas of increased uptake of 18F-FDG
(c) Areas of inflammation often show increased activity on 18F-FDG images.
Which of the following has the shortest half-life?
(a)82Rb
(b) 13N
(c) 15O
(d) 18F
(a) 82Rb has a half-life of 1.3 min, 13N has a half-life of 10 min, 15O has a half-life of 122.2 s, and 18F has a half-life of 109 min.
Which dose and route of administration are the best choices when performing a whole body PET scan with 18F-FDG and a dedicated PET scanner?
(a)2-4 mCi IV
(b) 2-4 mCi IM
(c) 10-20 mCi IV
(d) 10-20 mCi IM
(e) 30-35 mCi IV
(c) The dose recommended by the Society of Nuclear Medicine Procedure Guideline for whole-body FDG PET scanning is 10-20 mCi injected intravenously (370 to 740 MBq).
Fill in the blank. High blood glucose levels may _____ 18F-FDG uptake in tumors.
(a)Decrease
(b)Increase
(a) Increased glucose level can decrease tumor uptake so many institutions reschedule a patient’s PET scan if their blood glucose level exceeds 200 mg/dL.
Parenteral nutrition should be discontinued for several hours prior to 18FDG imaging.
(a)True
(b)False
(a) Regardless of how a patient receives his or her nutrition, increased glucose level may decrease tumor uptake because glucose will compete with FDG for cellular uptake. Of course, the decision to remove nutrition is up to the clinician.
Which of the following is NOT a scintillation crystal found in PET cameras:
(a)Lutetium oxyorthosilicate (LSO)
(b) Bismuth germanate (BGO)
(c) Lead sulfate (PbSO4)
(d) Gadolinium oxyorthosilicate (GSO)
(c) Scintillation crystals that have been used in PET cameras include NaI(Tl), LSO, BGO, and GSO. Lead sulfate, PbSo4, is the white powder often seen on the electrodes of car batteries.
In the event of a spill of 99mTc to clothes, one should immediately:
(a)Enter a shower fully clothed.
(b) Remove and store the clothes until they decay to background.
(c) Wash the clothes in hot water and then survey them to determine remaining activity.
(d) Remove and destroy the clothing.
(b) The first priority in event of a spill is to contain the contamination, i.e., to keep it from being spread. In this case, that would be accomplished by removing the clothing and storing it until the activity has decayed to background level.
What is the best way to decrease the radioactive dose to visitors if a patient is surveyed to emit 3 mR/h at bedside?
(a)Have the patient wear lead aprons.
(b) Keep the patient well hydrated and encourage frequent voiding.
(c) Have the visitor sit or stand as far as possible from bedside.
(d) Have the visitor wear lead shielding.
(c) The best and simplest way to decrease exposure to a visitor would be to increase the distance form the patient. If the exposure rate is 3 mrem/h at bedside, we can estimate 1 ft. from the patient and we move the visitor to 2 ft. from the patient, the exposure rate at the new distance would be 0.75 merm/h. (The equation in solution to question 5 of this chapter is rearranged to read (I1)(d1)^2 = (I2)(d2)^2 and solved for the new intensity.)
A spill of 99mTc increases the exposure rate in a room from 1.7 to 3.15 mR/h. The room is posted with a sign reading “Caution-Radioactive Materials.” What would be the ideal solution?
(a)Change the sign to one reading “Caution-Radiation Area.”
(b) Call the NRC.
(c) Decontaminate the floor with water and cleanser.
(d) Place absorbent paper over the spill and close the room until the activity has decayed.
(d) A sign reading “Caution Radioactive Materials” is required wherever radioisotopes are used. The sign reading “Caution Radiation Area” sign is required if the dose rate exceeds 5 mrem/h, so no change in sign posting is needed. However, the spill should be contained, so restricting access to the area until the activity has decayed to background is the best course of action.
A technologist has 500 mrem registered on his ring badge in 1 month. What should be done to decrease exposure in the future?
(a)Use lead pigs and syringe shields when preparing radiopharmaceuticals.
(b) Have another technologist elute the generator.
(c) Wear lead aprons.
(a) All technologists should use lead vials and syringe shields when working with radiopharmaceuticals.
Which of the following is the most effective means of measuring low levels of removable radiation?
(a)By performing an area survey
(b) By performing a wipe test
(c) With a pocket dosimeter
(d) With a TLD
(b) Wipe tests are used to detect removable contamination from surfaces such as packages, floors and counters and are achieved by wiping the area in question with a dry wipe and then counting the wipes along with a background sample in a well counter.
If a radiopharmaceutical is spilled on the floor, the first priority is to:
(a)Contact the Radiation Safety Officer.
(b) Pour a chelating solution over the area of the spill.
(c) Cover the area with absorbent paper and restrict access around it
(d) Call the housekeeping department to arrange for cleaning.
(c) The contamination must be contained as a first priority. Using a chelating agent may change the chemical structure of the substance spilled but will not affect the radioactivity of it. The Radiation Safety Officer should be notified, but first access to the area of the spill must be restricted.
Gaseous radiopharmaceuticals may only be used in rooms that:
(a)Have at least one window
(b) Contain an oxygen supply
(c) Are at a positive pressure compared to surrounding rooms
(d) Are at a negative pressure compared to surrounding rooms
(d) Airborne radiation, such as aerosols or gases, should be administered in rooms that are at negative pressure to surrounding areas. Depending on the amount of activity and the length of time it is present, special posting may be required (10 CFR 20.1902)
A technologist discovers that a patient in the room next to a radioiodine therapy will receive 2.5 mrem/h when lying in his bed which is against the shared wall. What should be done?
(a)Move the bed to the other side of the room.
(b) Discharge the therapy patient.
(c) Discharge the non-therapy patient.
(d) Calculate how long visitors to the non-therapy patient can stay.
(e) Calculate how long the patient may stay in bed each hour.
(a) Time, distance, and shielding are the most important factors in reducing exposure; in this case, the simplest solution is to employ an increase in distance to the source of the radiation.
Which of the following is not a misadministration?
(a)When a dose of 400 μCi of 99mTc MAA is given rather than 4 mCi
(b) When the correct dose of 111In oxine for cisternogram is injected intravenously
(c) When a patient who should have been injected with 20 mCi of 99mTc HDP for a bone scan receives a capsule containing 250 μCi of 123I intended for a thyroid patient
(d) When a patient who should have received 50 mCi of 131I receives 35 mCi instead
(e) None of the above
(e) A misadministration can involve the wrong patient, the wrong radiopharmaceutical, the wrong route of administration, or a dose that differs by more than 20% of the prescribed dose or falls outside the prescribed dose range. Doses that differ from the prescribed dose by more than 5 rem effective dose equivalent, 50 rem to an organ or tissue, or 50 rem shallow dose equivalent to the skin are also misadministrations.
What is the dose rate limit at the surface of a package bearing a DOT Class I White label?
(a)0.5 mR/h
(b) 2 mR/h
(c) 50 mR/h
(d) 100 mR/h
(e) 200 mR/h
(a) A package with such a label may have an exposure rate that does not exceed 0.5 mR/h at the package surface, and there must be no detectable radiation at 1 m from the package.
The doorway to the nuclear medicine reception area should be posted with:
(a)Caution: Radiation Area
(b) Caution: High Radiation Area
(c) Grave Danger: Very High Radiation Area
(d) Caution: Radioactive Materials
(e) None of the above
(e) The sign “Caution Radioactive Area” is posted wherever radioactive materials are used or stored. Unless patients are being injected in the reception area, a sign is not needed.
Which of the following bodies regulates the use of investigational pharmaceuticals?
(a)NRC
(b) DOT
(c) IRB
(d) FDA
(d) All the use of investigational pharmaceuticals is regulated by the Food and Drug Administration.
What is the best choice for disposal of a vial containing 27 mCi of 99mTc in 2 ml of liquid?
(a)Transfer to an authorized recipient
(b) Incinerate
(c) Bury
(d) Store until decayed to background
(e) Release to the atmosphere through evaporation
(d) If the radioactive material has a half-life of 120 days, the material can be disposed of as ordinary trash after decaying in storage. Before disposal, the material must be surveyed and not be greater than background radiation (10 CFR 35.92). Records must be kept of this for 3 years (10 CFR 35.2092) and must include the radionuclide, the date of disposal, the equipment used to survey the material, the background dose rate, and the dose rate at the surface of the container used for disposal, as well as the name of the person disposing of the material.
Reports of area surveys must include all of the following except:
(a)A diagram of the areas surveyed
(b) Equipment that was used to perform the survey
(c) Date performed
(d) Initials of the person who performed the survey
(e) List of isotopes used in the area
(e) NRC licensees are required to prepare and maintain reports of area surveys for 3 years. A list of isotopes used in the area is not a required part of the report.
Which of the following must be kept for 5 years?
(a)Records of misadministrations
(b) Records of dose calibrator linearity
(c) Records of doses assayed before administration
(d) Area survey records
(e) Records of instructions to breast-feeding women who received radiopharmaceuticals
(a) Misadministration records must be kept for 5 years. Records of patient dosage, area survey records, and records of instructions given to lactating females must be kept for 3 years.
A pregnant technologist receives 350 mrem during her pregnancy according to a film badge worn at waist level. Has the NRC dose limit for the fetus been exceeded?
(a)Yes
(b)No
(b) The total dose limit for a fetus is 0.5 rem (10 CFR 20.1208)
Which of the following must be done during disposal of a carton in which a shipment of 131I was received?
(a)RSO must be notified.
(b) Carton must be stored for ten half-lives before disposal.
(c) Radioactive labels must be removed or obliterated.
(d) Carton must be discarded with biohazardous waste.
(e) (b) and (c).
(c) Cartons that have been used toe ship radioactive material must have radiation labels removed before disposal. If wipe tests show contamination, it must be regarded as radioactive waste and disposed according to the relevant regulations.
OSHA requires that personnel exposure records be provided to employees:
(a)Monthly
(b) Quarterly
(c) Annually
(d) Biannually
(c) OSHA requires that employees are advised at least yearly about their exposure records.
A technologist is working in a hot lab where the exposure rate is 20 mR/h. What sign should be on the door?
(a)Caution: Radioactive Materials
(b) Caution: Radiation Area
(c) Caution: High Radiation Area
(d) Grave Danger: Very High Radiation Area
(e) None of the above
(b) The sign reading “Caution Radiation Area” sign is required if the dose rate exceeds 5 mrem/h. The sign reading “Caution: High Radiation Area” is not required until the dose rate exceeds 100 mrem/h.
Any patient who is treated with 90 Y ibritumomab tiuxetan must be hospitalized for at least 24 h.
(a)True
(b)False
(b) The dose is 0.4 mCi/kg and is not to exceed 32 mCi. In general, patients may be released from hospitalization based on measured dose rates or on the basis of activity administered or retained; the activity below which a patient may be released differs according to the isotope (e.g., 33 mCi for 131I). However, for 90Y, 32P, and 89Sr, the NRC does not require hospitalization because the exposure to the public form doses normally used is minimal.
A room containing a 57Co sheet source is posted with a sign reading “Caution-Radioactive Materials.” The exposure rate measured next to the source is 5.2 mR/h. What should be done?
(a)Change the sign to one reading “Caution-Radiation Area.”
(b) Store the source in a leaded container.
(c) Monitor the length of time a technologist can work near the source.
(d) None of the above.
(b) According to the NRC regulations for sing posting, the sign should be changed to “Caution Radiation Area,” but a simpler solution would be to store the source in its leaded container.
If bleeding occurs during withdrawal of a needle following injection, one should:
(a)Apply a tourniquet
(b) Apply pressure
(c) Alert a physician
(d) Apply ice
(b) Bleeding following an IV injection is halted by applying pressure. In cases of severe or prolonged bleeding, a physician should be alerted.
Which of the following should be considered when using patient restraint devices?
(a)Restricted circulation
(b) Attenuation
(c) Comfort
(d) All of the above
(e) (a) and (c) only
(d) Patient restraint devices should not restrict circulation and patient comfort is important. Buckles on straps, etc. may produce attenuation artifacts.
If a patient is having seizures, the technologist should:
(a)Try to restrict the patients’ movements
(b) Try to grasp the patient’s tongue
(c) Start CPR
(d) Clear the area around the patient to minimize the risk of injury
(e) All of the above
(d) Regardless of the seizure type, patients should not be restricted and nothing should be inserted into their mouth as this will increase the risk of injury. Removing objects that could potentially injure the patient and prevention of injury is a priority for the healthcare provider during the seizure. It is not necessary to start CPR in cases of seizure (unless, of course, the seizure is provoked by a stroke or other serious medical condition and the patient’s heartbeat and breathing cease).
Infectious waste disposal involves:
(a)Leakproof containers
(b) Puncture-resistant containers
(c) The universal symbol for biohazard
(d) All of the above
(e) (a) and (b) only
(d) Infectious waste should be disposed of using the universal biohazard symbol, which is recognized by the World Health Organization and numerous national agencies. Sharps should be disposed of using puncture-resistant containers, and all containers and bags should be leakproof.
Gloves should be worn anytime there is contact with:
(a)Blood and body fluids
(b) Broken skin
(c) Mucous membranes
(d) All of the above
(e) (a) and (b) only
(d) While nasal secretions do not require universal precautions, vaginal secretions do, and the vaginal lining is a mucous membrane. Hence, mucous membranes are included in the correct answers. In practice, nuclear medicine technologists rarely have contact with mucous membranes.
According to the standard precautions issued by the Centers for Disease Control, when should gloves be changed?
(a)Between procedures on two different patients
(b) Between procedures on the same patient
(c) Every half hour
(d) All of the above
(e) (a) and (b) only
(f) (a) and (c) only
(e) The Centers for Disease Control and Prevention recommends changing gloves between patients and between procedures on a single patient if moving from a contaminated area to a clean area. There is no specific frequency recommendation.
Which of the following statements is not true regarding sharp instruments?
(a)Reusable instruments should be cleaned, disinfected, and sterilized before reuse.
(b) Nonreusable sharp instruments should be recapped before disposal into a biohazard container.
(c) Single-use needles should be disposed using puncture-resistant containers.
(d) None of the above.
(b) Single-use sharps should not be recapped before disposal as the proper disposal container is puncture resistant and recapping will increase the risk of puncturing the skin of the user.
A nursing mother who undergoes a lung perfusion exam utilizing 4 mCi of 99mTc MAA should:
(a)Continue nursing as usual
(b) Interrupt breast-feeding for 12.6 h
(c) Interrupt breast-feeding for 36 h
(d) Discontinue breast-feeding
(b) The International Commission on Radiological Protection recommends delaying breast-feeding for 12 h after 99mTc-labeled radiopharmaceuticals except for labeled red blood cells, phosphonates, and DTPA for which 4 h of interruption is recommended. Three weeks is recommended after 201Tl-, 67Ga-, and 125I-labeled compounds. It is recommended that breast-feeding be completely discontinued after 131I therapy.
Which of the following is true concerning radioactivity and pregnancy?
(a)Radioiodine will cross the placenta.
(b) Hydration and frequent voiding will reduce the fetal absorbed dose.
(c) The NRC total dose allowed to an embryo/fetus from occupational exposure is 0.5 rem.
(d) All of the above.
(d) The use of radiopharmaceuticals is not encouraged during pregnancy. Iodine, and therefore radioiodine, crosses the placenta from the mother to the child, and therefore, radioiodine therapy can damage the baby’s thyroid. Women are advised to delay pregnancy for a year following radioiodine therapy. The international Atomic Energy Agency recommends lower doses followed by hydration and frequent voiding to reduce fetal exposure for pregnant women who have undergone examinations using radiopharmaceuticals. Hydration without frequent voiding will increase the dose to the fetus. The total dose equivalent allowed to the fetus from occupational exposure of the mother is 0.5 rem.
Which of the following must be performed every 6 months at minimum?
(a)COR
(b) Sealed source leak test
(c) Linearity of the dose calibrator
(d) Area survey of hot lab
(b) Sealed sources must be leak checked during an inventory conducted every 6 months. Leak checks are made by wipe tests of the sealed sources.
A dose calibrator must undergo repair or replacement if accuracy or constancy errors are:
(a)Present
(b) Greater than 5%
(c) Greater than 10%
(d) Greater than 20%
(c) According to the NRC, dose calibrators with accuracy or constancy errors >10% must be repaired or replaced.
Which instrument should be used to determine the location of a 99mTc spill?
(a)Geiger-Muller (GM) survey meter
(b) Portable ionization chamber
(c) NaI well counter
(d) Pocket dosimeter
(a) Geiger-Muller (GM) survey meters are more sensitive than ionization chamber survey meters by a factor of ~10. This allows them to detect spills with very low levels of contamination.
Survey meters must be checked for proper operation against a sealed source:
(a)Before each day of use
(b) Weekly
(c) Monthly
(d) Every 6 months
(a) Before using a GM meter each day the user should perform: (1) battery test - check that needle goes up into region marked BAT TEST, (2) constancy test - hold the detector up against a check source and compare the measurement (minus background) to the expected value.
Which of the following would be used to perform a survey of an area in which a small amount of radioactivity is expected to be present?
(a)Ionization chamber
(b) Geiger-Muller counter
(c) Well counter
(d) Single probe counting system
(b) Geiger-Muller meters are designed to detect small amounts of contamination. Ionization chambers are not sensitive enough to use for contamination monitoring.
An ionization chamber with a relatively low applied voltage from the anode to the cathode has a low efficiency and is therefore best for measuring:
(a)Low exposure rates
(b) High exposure rates
(c) Background radiation
(d) Absorbed dose
(b) Because of the low voltage, there is no avalanche effect, and therefore no dead time.
Most well counters measure radioactivity by the use of:
(a)An applied voltage from anode to cathode
(b) A sodium iodide crystal
(c) A silver halide layer
(d) Thermoluminescent crystals
(b) Thermoluminescent crystals are used for monitoring radiation exposure to occupational personnel. The Geiger-Muller counter uses an applied voltage from anode to cathode. Silver halide coats the film often used in nuclear medicine departments.
When measuring samples in a well counter, which one of the following is true?
(a)Sample volumes should be large.
(b) Samples should have high radioactivity.
(c) Sample geometry should be consistent.
(d) Sample containers don’t affect the measurement.
(c) Well counters best measure samples containing small amounts of radioactivity and are useful for counting in vitro studies, wipe tests, etc. Samples should have identical geometry, i.e., the volumes, and containers used should be identical for all samples.
A locked storage closet next to the radiopharmacy containing phantoms and sealed sources has a measured exposure rate of 3 mR/h. It should be posted with a sign reading:
(a)Caution: Radioactive Materials.
(b) Caution: Radioactive Area.
(c) Caution: High Radiation Area.
(d) Grave Danger: Very High Radiation Area.
(e) No sign is necessary.
(a)
Film badges should be worn:
(a)Between the shoulder and waist
(b) Except while doing paperwork
(c) Only during preparation and administration of radiopharmaceuticals
(d) All of the above
(a)
According to NRC, an unrestricted area is one in which a person would receive a radiation dose of less than:
a. 2 mrem/hr
b. 5 mrem/hr
c. 10 mrem/hr
d. 20 mrem/hr
e. 50 mrem/hr
a.2 mrem/hr
High Radiation Area signs are to be posted in areas where exposures greater than ____________ mrem/hr are measured at 30 cm from the source or from any surface through which the radiation penetrates:
a. 5
b. 10
c. 50
d. 100
e. 500
d.100
The first step that a technologist should initiate in a safe environment when an adult patient is determined to be unresponsive is to:
(a)Perform chest compressions.
(b) Establish an airway.
(c) Check for a carotid pulse.
(d) Call for help.
(e) Perform rescue breathing.
(d) American Heart Association standards and guidelines indicate that once verification of cardiac arrest has occurred, the rescuer should call for help first and then initiate CPR.
A biohazard warning label would be found on all of the following EXCEPT a:
(a)contaminated sharps container
(b) refrigerator containing potentially infectious material
(c) receptacle for contaminated laundry
(d) unit of blood released for clinical use
(e) uncontaminated sharps container
(d) Biohazard warning labels are attached to any container of regulated materials. These include refrigerators, freezers, and anything used to store, transfer, or ship blood or infectious materials. Labels are not required on containers of blood that have been released for clinical use, such as blood transfusion
According to the NRC, imaging rooms should be posted with which of the following signs?
(a)No posting is required.
(b) “Caution: No Food or Drink”
(c) “Caution: Radiation Area”
(d) “Caution: Radioactive Materials”
(e) “Caution: High Radiation Area”
(d) The NRC requires that restricted areas, such as imaging rooms, be posted with specific signs depending on the radiation level present. A “Caution: Radioactive Materials” sign should be posted in areas where certain quantities of radioactive materials are used or stored. There quantities are those exceeding 10 times the quantities specified in Appendix C to 10 CFR Part 20. The quantities for commonly used radionuclides that will result in required posting include: as excess of 10 mCi of 99mTc, 67Ga, 133Xe, or 201 Tl; an excess of 1 mCi of 123I or 111In; more than 10 uCi of 131I.