Board Review

Question 1

What is the half-life and energy of Thallium 201?

Answer 1

half-life = 72 hours
energy= 70-83 KeV

Question 2

How is thallium 201 produced?

Answer 2

cyclotron produced
(a cyclotron is a particle accelerated which uses rapidly varying electric fields within a static magnetic field to make ions accelerate in a spiral pattern)

Question 3

How is thallium taken up by myocardium and where does it go in the cell?

Answer 3

thallium is a potassium analog so it’s uptake is via active transport via Na-K pump, distribution similar to sodium (primarily intracellular)

Question 4

What is the extraction fraction of thallium

Answer 4

85%

Question 5

How is technetium produced?

Answer 5

produced from a generator; parent molecule is molybdenum

Question 6

What is the half-life and energy of technicium 99m

Answer 6

half-life = 6 hours
energy = 140 KeV

Question 7

where is energy resolution usually set to measure (range of energies)

Answer 7

full width of half-maximum (on the Gaussian curve)

Question 8

how are sestamibi and tetrofosmin transported to cells, where do they go

Answer 8

passive transport (lipophilic) and they localize to mitochondria

Question 9

in conventional cameras how do the gamma rays from patient get turned into an image

Answer 9

gamma ray hits a crystal (sodium iodide) which generates light photons which then are amplified in photomultiplier tubes

Question 10

An isotope has the same number of _____and different number of ______

Answer 10

Same number of protons (so same chemical properties) but different number of neutrons (different radioactive properties)

Question 11

Legal limit radiation dose to whole body

Answer 11

5 rem/ year

Question 12

Legal limit of radiation to organs

Answer 12

50,000 mrem/year

Question 13

1 rem = how many rad alpha, beta, and gamma

Answer 13

1 rem = 1 rad beta or gamma and 20 rem = 1 rad alpha

Question 14

What are exposure units and how are they related

Answer 14

1 roentgen = approximately 1 rad

Question 15

How many rads in 1 Gy

Answer 15

100 rads = 1 Gy

Question 16

How many rem in 1 Sv

Answer 16

100 rem in 1 Sv

Question 17

Dose measurements are

Answer 17

Rad and Gy

Question 18

Dose equivalent units are

Answer 18

Rem and Sv

Question 19

Radionuclide of choice for standard first pass radionuclide angiography

Answer 19

Tc99m-DTPA (diethylamine triamine pentaacetic acid)

Question 20

Webster’s rule

Answer 20

Used to calculate appropriate dose in children: (age +1)/(age+7) * adult dose

Question 21

How often should uniformity be checked

Answer 21

Daily

Question 22

A radiation area is defined as any location where a person can receive _____ mrem/hr at distance of 30cm from source

Answer 22

5 mrem

Question 23

What is the acceptable concentration of Mo99 breakthrough in Tc99m sample?

Answer 23

0.15 µCi of Mo99 / mCi of Tc99m

Question 24

What energy photons does Mo99 emit?

Answer 24

740 and 780 keV