Photon Treatment Planning Flashcards
1
Q
At what photon energy do you start to get significant neutron contamination?
A
25 MV
2
Q
What is the % of dose that gets into the depth of 10 cm for 6 MV and 18 MV
A
67% vs. 80%
3
Q
Define PRV (Planning at Risk Volume)?
A
OAR (Organ at Risk) plus margin
4
Q
Define V20 for a lung
A
The volume of lung receiving greater than or equal to 20 Gy
5
Q
What is the problem with DVH?
A
There is NO spatial information
