Radiation Therapy Techniques || Acknowledged Answers 100%.
Mark all concerning wedges:
- reduce hot spots
- can be hard or dynamic
- used for tissue compensating of sloping surfaces
- known as superflab correct answers - reduce hot spots
- can be hard or dynamic
- used for tissue compensating of sloping surfaces
Irradiated volume correct answers Volume of tissue receiving a significant dose (50% or more of
the prescribed dose)
GTV correct answers The gross, palpable, visible, or clinically demonstratable location of the
cancerous growth
CTV correct answers Tissue volume that contains the clinical and subclinicall disease
PTV correct answers Surrounds the clinical and subclinical growth and an additional margin to
compensate for different types and variations and uncertainties of the beam
Treated volume correct answers Larger than the target volume, encompasses the additional
margins around the target to allow for limitations of the treatment technique
Localization correct answers geometrical definition of the tumor and anatomic structures using
surface or fiducial marks for reference
Verification correct answers a check that each beam/port covers the intended treatment area and
spares organs at risk
,Simulation correct answers The process carried out by the radiation therapist under the direction
of the radiation oncologist. This is a mock up of the patient positioning for treatment
IFD correct answers Patient separation between two beams
Is a photon beam heterogenous or homogenous? correct answers Heterogenous
What is the average energy of an 18MV beam? correct answers 6mv
SAD setup correct answers iso in 100 or less
SSD setup correct answers iso is 100 or more
What is the importance of shielding blocking devices correct answers - high intensity
- high atomic number
- low melting point
Shielding material should the original intensity of the beam to ___% or less correct answers 5
MLC or blocks should be at least ___ cm away to avoid ___scatter correct answers 15-20,
electron
What are the material and amount of those materials in cerrobend? correct answers Bismuth -
50%
Lead - 26.7%
Tin - 13.3%
Cadmium - 10%
, What is the most toxic ingredient in cerrobend? correct answers Cadmium
What is true about compensators? correct answers - maintain skin sparing
- used for tissues with different densities
- allow for normal depth dose for irregular surfaces
What are the different types fo wedge filters? correct answers - EDW
- Virtual
- Dynamic
- Individualized
What does bolus change? correct answers The location of DMAX
What does bolus do to skin sparing? correct answers Decreases skin sparing because DMAX
depth is decreased.
What angle are EDW wedge filters measured at? correct answers 10cm
Do compensators affect DMAX? correct answers no
4mv DMAX correct answers 1cm
6mv DMAX correct answers 1.5 cm
10mv DMAX correct answers 2.5cm
Mark all concerning wedges:
- reduce hot spots
- can be hard or dynamic
- used for tissue compensating of sloping surfaces
- known as superflab correct answers - reduce hot spots
- can be hard or dynamic
- used for tissue compensating of sloping surfaces
Irradiated volume correct answers Volume of tissue receiving a significant dose (50% or more of
the prescribed dose)
GTV correct answers The gross, palpable, visible, or clinically demonstratable location of the
cancerous growth
CTV correct answers Tissue volume that contains the clinical and subclinicall disease
PTV correct answers Surrounds the clinical and subclinical growth and an additional margin to
compensate for different types and variations and uncertainties of the beam
Treated volume correct answers Larger than the target volume, encompasses the additional
margins around the target to allow for limitations of the treatment technique
Localization correct answers geometrical definition of the tumor and anatomic structures using
surface or fiducial marks for reference
Verification correct answers a check that each beam/port covers the intended treatment area and
spares organs at risk
,Simulation correct answers The process carried out by the radiation therapist under the direction
of the radiation oncologist. This is a mock up of the patient positioning for treatment
IFD correct answers Patient separation between two beams
Is a photon beam heterogenous or homogenous? correct answers Heterogenous
What is the average energy of an 18MV beam? correct answers 6mv
SAD setup correct answers iso in 100 or less
SSD setup correct answers iso is 100 or more
What is the importance of shielding blocking devices correct answers - high intensity
- high atomic number
- low melting point
Shielding material should the original intensity of the beam to ___% or less correct answers 5
MLC or blocks should be at least ___ cm away to avoid ___scatter correct answers 15-20,
electron
What are the material and amount of those materials in cerrobend? correct answers Bismuth -
50%
Lead - 26.7%
Tin - 13.3%
Cadmium - 10%
, What is the most toxic ingredient in cerrobend? correct answers Cadmium
What is true about compensators? correct answers - maintain skin sparing
- used for tissues with different densities
- allow for normal depth dose for irregular surfaces
What are the different types fo wedge filters? correct answers - EDW
- Virtual
- Dynamic
- Individualized
What does bolus change? correct answers The location of DMAX
What does bolus do to skin sparing? correct answers Decreases skin sparing because DMAX
depth is decreased.
What angle are EDW wedge filters measured at? correct answers 10cm
Do compensators affect DMAX? correct answers no
4mv DMAX correct answers 1cm
6mv DMAX correct answers 1.5 cm
10mv DMAX correct answers 2.5cm
