LET, OER, RBE

Question 1

For a given particle, LET _____ with higher energy

Answer 1

decreases

Question 2

LET of 75 MeV argon

Answer 2

250 … VERY high

Question 3

LET of 18 MeV carbon

Answer 3

108

Question 4

LET of 2.5 alpha particles

Answer 4

170

Question 5

carbon ion RBE

Answer 5

D250/D(r)
D250 = dose of 250 kV x-rays
D(r) = equivalent dose to achieve same effect

Question 6

Carbon ion RBE in ____ in hypoxic vs aerated conditions

Answer 6

higher

Question 7

Densely or Sparsely ionizing?

B particles

Answer 7

sbarsely

Question 8

Densely or Sparsely ionizing?

a particles

Answer 8

densely

Question 9

Densely or Sparsely ionizing?

gamma particles

Answer 9

sparsely ionizing along tracks of electrons

However I-125 decay is electron capture followed by gamma decay at very low energy and thus is densely ionizing.

Question 10

What can assay the extent and location of hypoxia in tumors?

Answer 10

EPR imaging - electron paramagnetic resonance imaging

Question 11

OER of X-rays

Answer 11

2-3.5
Higher at high doses
lower at low doses

Question 12

what stains hypoxia

Answer 12

pimonidazole