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Question 1

Molybdenum breakthrough allowed by NRC

Answer 1

May not exceed 0.15 microCi of Mo-99 per 1 mCi of Tc-99m

Question 2

Minimum peak pixel count in LV myocardium on a planar technetium-99m SPECT projection?

Answer 2

200 counts/pixel (anterior projection)

Question 3

Minimum peak pixel count in LV myocardium on a planar thallium-201 SPECT projection?

Answer 3

100 counts/pixel

Question 4

Compared to adenosine, its receiving regadenoson are more likely to have what?

Answer 4

headaches

Question 5

Prone imaging improves SPECT MPI accuracy because it allows recognition of what?

Answer 5

Diaphragmatic attenuation

Question 6

Nitrates-enhanced technetium-99m sestamibi test in evaluating hibernating myocardium compared to thallium rest-distribution

Answer 6

higher NPV and higher PPV

Question 7

11C-heptagluconate is a tracer of:

Answer 7

myocardial fatty acid utilization

Question 8

11C-hydroxyephedrine is a tracer of:

Answer 8

depict sympathetic innervation of the myocardium

Question 9

FDG is a tracer of:

Answer 9

myocardial glucose metabolism

Question 10

11C-acetate is a tracer of:

Answer 10

myocardial oxidative substrate metabolism;

can also be use to assess myocardial perfusion given high first-pass myocardial extraction fraction; images obtained early following tracer injection can be used to measure regional tissue blood flow.

Question 11

Organ receiving highest radiation dose in a rubidium-82 PET perfusion study?

Answer 11

Kidneys, than heart

Question 12

Minimum number of acquisition projections or stops recommended for SPECT acquisition over 180 degrees using technetium-99m and thallium-201?

Answer 12

technetium-99m: 60-64

thallium has lower resolution, so 32 projections

Question 13

well counter

Answer 13

most sensitive and practical for measuring the swipes that are to test packages delivered to a nuclear lab.

solid scintillation counter and is very sensitive to low levels of radioactivity

Question 14

dose calibrator

Answer 14

used routinely to measure radiotracer doses prior to being injected into the patient

Question 15

ionization chamber

Answer 15

a gas-filled enclosure between two conducting electrodes that can be used to measure gases, liquids, or solid

Question 16

Geiger counters

Answer 16

used to detect ionizing radiation (usually beta particles, gamma rays, some can detect alpha particles)

an inert gas-filled tube (usually helium, neon, or argon with halogens added) briefly conducts electricity when a particle or photon of radiation makes the gas conductive.

Question 17

In-vitro labeling of RBCs

Answer 17

ultratag

1-3 ml heparinized blood added to vial containing stannous citrate and incubated at room temperature for 5 minutes. During incubation period, the stannous ion diffuses the RBC membrane after which sodium hypochlorite along with acid citrate dextrose is added to the reaction vial, followed by the addition of 30-40 mCi of sodium pertechnetate-technetium-99m and incubated for another 20 minutes. extracellular stannous ion is oxidized by the sodium hypochlorite. The pertechnetate-technetium-99m diffuses the RBC membrane and is reduced inter cellularly by the stannous ions. Reduced pertechnetate-technetium-99m doesn’t diffuse out of the RBC.

Typical labeling efficiency is >97%.

Question 18

mSV of SPECT MPI vs Rb82 or NH3 based PET MPI

Answer 18

SPECT MPI (technetium): 12-16 mSV

Pet Rb82: 3.7 mSV

PET NH3: 2.3 mSV

Question 19

Annualized event rate for patients with non-ischemic PET perfusion studies and calcium scores between 400-999:

Answer 19

5%

Question 20

Radioactive signs

Answer 20

not required where radioactive materials are handled for <8 hrs and are under constant observation, and in rooms where sealed sources are stored and the exposure doesn’t exceed 5 mrem/hr at 1 m

Question 21

White I limits

Answer 21

surface < 0.5 mR/h

at 1m <1

Question 22

Yellow II

Answer 22

Surface >0.5, <50 mR/h

at 1 m, >1, <10

Question 23

Yellow III

Answer 23

Surface >50, <200 mR/h

Question 24

Breast feeding after exercise stress Tl-201

Answer 24

stop for 2 weeks after test

Question 25

PET - Attenuation correction, what rotating rod sources/rings used to acquire a transmission scan for attenuation correction

Answer 25

Germanium-68 (Ge-68/Gallium-68) or Cesium-137

Question 26

Calculation of effective half-life (Te)

Answer 26

1/Te = 1/Tp + 1/Tb

Question 27

Caution: Very high radiation area sign should be posted in area where radiation exceed

Answer 27

>500 rads/hr at 1 m

Question 28

Fluorine-18 half life

Answer 28

110 minutes

Question 29

Technetium-99m half life

Answer 29

6 hours

Question 30

thallium-201 half life

Answer 30

3.04 days or 73 hours

Question 31

Cobalt-57 half life

Answer 31

271.7 days

Question 32

NRC annual body radiation exposure limit for a radiation is:

Answer 32

whole body dose 5 rem/year specific organ limits: 15 rem for eyes, 50 rems for extremities

Question 33

Rubidium-82 is made in: Carbon-11 is made in: Fluorine-18 is made in: Nitrogen-13 is made in:

Answer 33

Rubidium is made in generator (eluted from a strontium-82/rubidium-82 generator) The rest are from cyclotrons

Question 34

Danger: Radiation area

Answer 34

Unrestricted area of a nuclear imaging facility. If <2 mrem/hr, do not require posting

Question 35

Transportation index is a measure of:

Answer 35

exposure measurement at 1 m from the surface of the package

Question 36

NRC max. exposure for a pregnant occupational worker is:

Answer 36

500 mrem for entire pregnancy (declared pregnant worker)

Question 37

Technetium-99m tracers artifacts:

Answer 37

liver and GI activity --> scatter, scaling, or normalizing problems Ramp filter artifacts associated with filtered back projection during reconstruction

Question 38

Extraction fraction across coronary bed - Technetium-99m agents vs Tl-201

Answer 38

lower in Technetium-99m

Question 39

Technetium-99m vs thallium

Answer 39

higher photo energy resulting in less tissue attenuation

Question 40

administration of nitrates prior to the resting injection mages of technetium-99m MPI helps:

Answer 40

improves readers' ability to detect viable myocardium in severely hypo-refused segments (similar to thallium)

Question 41

Regadenoson half life

Answer 41

initial IV phases of 2 minutes, then a longer intermediate phase of 30 minutes, and a third phase of 2 hours

Question 42

CKD and normal SPECT annual cardiac death rate

Answer 42

2.7%

Question 43

No CKD and normal SPECT annual cardiac death rate

Answer 43

0.8%

Question 44

CKD and scar annual death rate

Answer 44

5.7%

Question 45

CKD and ischemia annual death rate

Answer 45

11%

Question 46

DTS annual CV mortality: | high =5

Answer 46

=5% annual CV mortality | >=5 is 0.5% annual CV mortality

Question 47

Nitrogen-13 ammonia

Answer 47

in some pos, there may be a decrease in nitrogen-13 ammonia uptake in the inferolateral region of the ventricle

Question 48

FDG PET trapping mechanism

Answer 48

Once FGD is transported across the cell membrane via GLUT transport proteins (GLUT-1 and LGUT-3 for macrophages), it is phosphorylated by the enzyme hexokinase to FDG-6-phosphate; addition of the phosphate moiety to the molecule largely traps the FDG within the cells, as FDG-6-phospate is a poor substrate for further glycoltytic or glycogen synthetic pathways

Question 49

13NH3 activity in cell

Answer 49

13NH3 passively crosses the myocyte cell membrane, once within the cytosol of the cell it is metabolically trapped as glutamine via the glutamine synthase reaction

Question 50

FDG highest dose organ

Answer 50

urinary bladder

Question 51

Radiation hormesis

Answer 51

a protective effect of exposure to low amounts of ionizing radiation

Question 52

Rubidium-82 highest dose organ

Answer 52

kidneys

Question 53

Adenosine's common adverse event

Answer 53

Second degree AVB (4.1%) > hypotension (1.8%) > bradycardia (0.2%) > third degree AVB (0.8%)

Question 54

Agents that can be used for detection of a recent ACS

Answer 54

I-123 BMIPP (fatty acid analog that is not taken up in areas of infarction due to cell damage) Technetium-99m Myoscint (antibody directed to myosin that is exposed following acute damage and detects damage earlier than technetium-99m pyrophosphate) Technetium-99m pyrophosphate is retained in areas of healing infraction that has been used for detection of infarcts that are 3-7 days old