Nuclear Medicine Review Questions

A 99mTc MDP bone scan dose was prepared at 7:00 a.m. and contained 32 mCi/2 ml.At 9:00 a.m.,when the patient arrives, the technologist realizes that the patient's age was overlooked (13 years). The technologist would now like to adjust the dose to 11 mCi. Given a 2 hour decay factor of 0.794,what volume should be discarded so that the correct dose remains in the syringe?

1.13 ml

99mTc MAA has a biologic half-life of 2-4 hours; what will the effective half-life be?

1.5-2.4 hours

If a kit contains 140 mCi of 99mTc in 23 ml at 9:00 a.m., how much volume must be withdrawn to obtain a dose of 5 mCi at 3:00 p.m.?

1.6 ml

What is the maximum amount of aluminum ions (Al3+ ) allowed in one milliliter of 99mTc eluate according to the USP?

10 μg

What is the most likely size of an MAA particle if correctly prepared?

10-30 μm

If a bone scan has been ordered on a 5-year-old girl, and the physician prescribes 62% of the adult dose to be given, how many mCi should be administered?

12.4 mCi

If an assay of a vial containing 131I shows 50 mCi present on May 2, approximately what will the assay show on May 18?

12.5 mCi

65) Which of the following radionuclides is not a positron emitter? a. 82Rb b. 15O c. 18F d. 14C e. 68Ga

14C

If a kit has 310 mCi of activity present at 8:00 a.m.,what will the vial assay show in 4 hours and 10 minutes if the decay factor is 0.618?

192 mCi

73) Which of the following is true regarding 18FDG? a. its distribution in the brain is related only to blood flow b. it is a potassium analog c. it has a half life of 60 minutes d. it is taken up by a disease free myocardium

d. it is taken up by a disease free myocardium

57) Following reconstitution of a kit with 99mTc pertechnetate, a technologist should ensure that all of the following are present on the vial except: a. date and time of preparation b. lot number c. concentration and volume d. patient name or identification number

d. patient name or identification number

The advantages of albumin colloid over sulfur colloid include:

does not require boiling

What method is used to calculate pediatric dose? a. according to weight b. Clark's formula c. according to body surface area d. using Talbot's nomogram e. all of the above

e. all of the above

69) Which of the following will not affect the distribution of 18FDG on a PET image? a. intense physical activity the day before imaging b. serum insulin level c. serum glucose level d. bladder catheterization e. all of the above affect distribution

e. all of the above affect distribution

49) To reduce the possibility of pyrogenic reactions, all kits should be prepared using saline that contains bacteriostatic preservatives.

false

The physical half life of a radionuclide is the time it takes:

for the nuclide to decay to one half of the original activity.

50) While performing a GI bleeding study with labeled red blood cells, a technologist notices gastric activity that he suspects is the result of free pertechnetate.What could be done to support this suspicion?

image the thyroid

53) Radiochemical impurities often result from:

introduction of water into the kit, introduction of oxygen into the kit, introduction of nitrogen into the kit.

Which of the following can be said regarding effective half-life?

it always shorter than both the physical and the biologic half-life

What can be said regarding precalibration factors?

it is not necessary for problem solving if the decay factor is available, and it is always >1.0

68) When 18FDG is transported across most cell membranes:

it is trapped in the cell and it is not further metabolized.

59) Testing for pyrogens is achieved by:

limulus amebocyte lysate assay

52) If excessive aluminum is present in 99mTc eluate,which of the following would be expected on a bone scan?

liver uptake

58) What is the difference between preparation of a 99mTcHMPAO kit for use in leukocyte labeling as compared to brain imaging?

methylene blue stabilizer is not added

48) Which of the following is not a desirable characteristic of radionuclides used for imaging?

particulate emission

60) If the proper centrifuge speed is not used during separation of cell types for leukocyte labeling with 111In oxine,what may happen?

platelets may be inadvertently labeled

Which of the following is an example of radiochemical impurity?

presence of free 99mTc in a preparation of 99mTc sulfur colloid

Following injection of 99mTc MAA for a perfusion lung scan, activity is seen in the kidneys and brain. This is indicative of:

right to left cardiac shunt

Which radiopharmaceutical is made with 99mTc without a reducing agent?

sulfur colloid

46) What will happen to the dose in question 47 if it sits for one hour?

the number of particles per mCi will increase

What is indicated by the front of an ITLC strip?

this depends on the solvent and strip used

The purpose of adding EDTA to sulfur colloid when labeling with 99mTc is:

to bind excess Al3+ and to prevent loss of the radiolabel

56) What is the purpose of adding hetastarch to a blood sample drawn for the purpose of leukocyte labeling?

to hasten the settling of erythrocytes

What is the role of the stannous ion in the preparation of pharmaceuticals labeled with 99mTc?

to reduce the valence state of 99mTc

54) It is proper technique to clean the septum of a kit reaction vial, and inject an amount of air equal to the volume being withdrawn when preparing a unit dose.

true

A vial of 99mTc eluate is tested for 99Mo breakthrough, and the amount of breakthrough is 25 uCi in 775 mCi at 6:00 a.m. Following the preparation of all kits to be used that day, 450 mCi of 99mTc is left. That night, a technologist is asked to perform a scrotal scan at 11:00 p.m.Must the generator be eluted again?

yes, because the molybdenum breakthrough will now exceed the limit allowed by the NRC

On a Monday morning at 6:00 a.m., a technologist is preparing a 99mTcECD kit that is to be used for the SPECT brain scans at 8:00 a.m., 9:00 a.m. and 10:00 a.m. Each patient should receive 10 mCi.What is the minimum activity that should be added to the kit during preparation?

42.6 mCi

If a preparation of 99mTc mertiatide has 60 mCi of activity present at 8:30 a.m., how many mCi will be present at 9:00 a.m.? (l = 0.944)

56.6

51) Convert 23 mCi to SI units.

850 MBq

64) If 630 mCi of 99mTc is eluted from a 99Mo/99mTc generator, what is the NRC limit of total 99Mo activity that may be present?

94.5 μCi

Which radiopharmaceutical,when correctly prepared, will have the smallest particle size?

99mTc human serum albumin

63) A 99Mo/99mTc generator exists in___________ equilibrium and the parent isotope has a __________ physical half life than the daughter isotope. a. transient, longer b. transient, shorter c. static, longer d. static, shorter

a. transient, longer

55) 15 rem is equal to: a. 150 mSv b. 15 Gy c. 15 Sv d. 150 MBq

a.150 mSv

66) When a neutron deficient nucleus emits a positron:

atomic mass number is unchanged

The presence of 12 μg Al3+ in 1 ml of 99mTc eluate is:

b. an example of chemical impurity

Which of the following is an example of radionuclidic impurity? a. presence of free 99mTc in a preparation of 99mTc sulfur colloid b. presence of 99Mo in 99mTc eluate c. presence of aluminum ions in 99mTc eluate d. presence of pyrogens in eluate

b. presence of 99Mo in 99mTc eluate

Which of the following is boiled during preparation? a. MAA b. sulfur colloid c. albumin colloid d. diphosphonates

b. sulfur colloid

70) Normal FDG distribution would show the least activity in the: a. brain b. bone c. bladder d. myocardium

bone

How does 201Tl decay?

by electron capture

72) 18FDG-PET is not an important tool for: a. restaging of colorectal cancer b. monitoring response to treatment of non-Hodgkins lymphoma c. detecting Helicobacter pylori d. imaging metastases in breast cancer

c. detecting Helicobacter pylori

74) 18FDG-PET images show a map of the ___________ distribution in the body. a. oxygen b. insulin c. glucose d. potassium

c. glucose

71) All positron emitting isotopes are produced in a cyclotron. True or False

False

A chromatography strip is used to test a kit for radiochemical impurity and is counted in a well counter. Part A contains 99mTc pertechnetate, and Part B contains bound 99mTc in the desired form. If the results show 258,000 cpm in Part B, and 55,000 cpm in Part A, can this kit be used for injection into patients? What is the approximate labeling efficiency %? What is the approximate radiochemical impurity of the kit?

NO, 82%, 18%

61) In reconstituted radiopharmaceutical kits, in what form is 99m Tc present? a. free pertechnetate b. bound technetium c. reduced, hydrolyzed technetium d. all of the above

d. all of the above

Which body decides on the acceptable levels of radionuclidic impurity? a. USP b. NRC c. FDA d. both a and b

d. both a and b

A vial containing 99mTc is assayed at 9:00 a.m. and contains 255 mCi. To calculate the remaining activity at 3:00 p.m.,what decay factor would be used?

.500

62) For determination of plasma volume, 10 μCi of human serum albumin in 2.5 ml is added to 500 ml of water. What is the concentration of the resulting solution?

0.019 μCi/ml

47) A volume of 5 ml containing 40 mCi of 99mTc is added to an MAA kit with an average of 3,000,000 particles. What volume of the reconstituted kit should be withdrawn to prepare a dose for a patient with severe pulmonary hypertension?

0.25 ml

What is the usual particle size of sulfur colloid?

0.3-1.0 μm

Determine the decay factor for 99mTc at 7 hours.

0.445

A MAA kit contains 40 mCi of 99mTc in 5 ml at 8:00 a.m. What would be the best volume to be withdraw at 10:00 a.m. if a perfusion lung scan is planned? (l = 0.794)

0.63 ml

If a kit contains 140 mCi of 99mTc in 23 ml, how much volume must be withdrawn to obtain a dose of 5 mCi?

0.8 ml

A vial of technetium eluate contains 50 mCi/ml. If 4 ml are withdrawn and added to a diphosphonate kit containing 16 ml of solution,what volume would then need to be withdrawn to prepare a 20 mCi dose at that moment?

2.0

If a 20 mCi dose of 99mTc HDP are needed at 9:00 a.m.,how much activity should the syringe contain if the technologist prepares it at 7:00 a.m.?

25.18 mCi

If the recommended volume for a MAG3 kit ranges from 4-10 ml, and the 99mTc eluate that will be used contains 820 mCi in 10 ml, and 41 mCi will be used,what is the minimum amount of diluent that should be added?

3.5 ml

44) A dose of 99mTc DMSA is prepared and calibrated to contain 5.0 mCi at 8:00 a.m. The patient arrives late at 10:00 a.m.Without using any tables of decay factors, determine what activity will remain in the dose at that time.

3.97 mCi

At 7:00 a.m., a technologist prepares a dose of 99mTcMDP for injection at 10:00 a.m. that day. The desired dose is 22 mCi and no precalibration factors are available. The three hour decay factor for the isotope is 0.707. What amount of activity should the technologist draw up into the syringe at 7:00 a.m.?

31.1 mCi

45) A MAA kit contains 950,000 particles per ml. The activity in the kit is 50 mCi of 99mTc in 5 ml. If a 4 mCi dose is drawn up, how many particles will be in the dose?

380,000

A diphosphonate kit should generally be used within how many hours after preparation?

4 hours

If the biological half-life of an isotope is 6 hours, and the physical half-life is 12 hrs,what is the effective half-life?

4 hrs

67) Which of the following has the shortest half life? a. 82Rb b. 13N c. 15O d. 18F

a. 82Rb

Which of the following has been used to abbreviate physical half-life? a.Tp b. T/2 c. T2 d. P 1/2

a. Tp