B. treatment verification Flashcards
(42 cards)
The _____is a point that the gantry, couch, and collimator rotate around
isocenter
____can be performed by using table parameters and a coordinate system
Shifts
Remember when performing shifts, they are in reference to
isocenter
____ isocenter shifts would require a positive table shift. or a addition to current table position.
Anterior, inferior, and right. ** remember AIR
The isocenter shifts ______would require a negative shift. OR a subtraction form the current table position
posterior, superior and left
if the lateral position of the couch is currently at the coordinate location of 1.5 and there is a right isocenter shift of 10.0, the new shifted couch coordinate should be
11.5cm. (10 + 1.5)
if the longitudinal position of the couch is currently at the coordinate location of 150.0 and there is a superior isocenter shift of 5.0, the new shifted couch coordinate should be
145 (150.0-5.0)
f the patient is head-first supine and the gantry is at an oblique angle of 45-degrees, the gantry angle would likely be called
LAO
if the patient is head-first prone, and the gantry angle is 90-degrees, the gantry angle may be named
right lateral
if the patient is feet-first supine, and the gantry angle is 270-degrees, the gantry angle may be named
left lateral
As the distance decreases (or gets closer to the source), the field size will measure
smaller than at isocenter
As the distance increases (or gets further from the source), the field size will measure
larger than at isocenter
______ treatment
2D
- based on conventional treatment planning
2D
- Uses a conventional simulator with x-ray equipment (fluoro simulation)
2D
- Provides a radiographic image with an outline of the tumor and a small margin
2D
- Dose distributions are limited to single fields or a few fields
2D
______ Treatments based on three-dimensional imaging to create a treatment plan
3D
- Most common imaging system is a CT simulator
3D
- Anatomy and critical structures are more accurately defined in three dimensions
3D
3D treatments use ___planning
forward
_____ is a Treatment that includes rotation of gantry with stationary MLCs (not modulated)
Non-volumetric ARC therapy
Four-dimensional treatment plan based on
4-D imaging
For _____ The radiation beam is on when the tumor is within a specific treatment position (based on a specific breathing cycle); the beam is turned off when the tumor moves out of the treatment position
4D