RAD BIO
The ratio of radiation dose needed to cause damage without a chemotherapy drug compared to the radiation dose needed with a chemotherapy drug is termed the
dose effect factor (DEF)
The half life of iridium - 192
About 74 days
Defining characteristic of ___ where tumors are treated with one fraction.
SRS
Linac daily output tolerance is +/- ___% for electron and photon therapy
3
This node receives almost all lymph from the head and neck area
jugulodigastric
TD 5/5 for bone marrow
250 cGy
What happens with kinetic energy in elastic collisions?
The total kinetic energy before the collision is the same as the total kinetic energy after the collision.
The beam energy chosen for the patient is chosen depending on these 2 factors.
the thickness of patient and depth of tumor
Field size tolerance is ___mm
2
This head and neck node is difficult or impossible to reach in surgery, which leads to a higher risk of distant metastasis.
retropharyngeal node/node of rouviere
When radiation occurs in the preimplantation stage, the most common effect is
prenatal death
This measures the total number of ionizations produced by photons in a unit mass of air
Exposure/Roentgen
parallel opposed portals have a hinge angle of
180 degrees
Tolerance for the mechanical check of gantry angle is __ degree.
1 degree.
Nasopharynx drains to these three nodes
cervical, retropharyngeal, jugulodigastric
These effects have a probability of occuring depending on the radiation dose.
stochastic
This scatter occurs in energies from 25 keV to 10 MeV
Compton
As energy, field size, and SSD increases, PDD will ___
increase
Tolerance for water is +/- __ HU
5
buccal mucosa drains to these two nodes
submandibular and subdigastric
Most resistant cycle phase
S phase
Electrons are released and visible light photons are emitted when they are excited by light instead of heat.
Optically stimulated luminescence
Adding a wedge will (increase/decrease) MU
increase
MLC position has __ mm tolerance
1
Subglottic cancer spread to these 3 nodes
pretracheal, paratracheal, inferior jugular nodes