Term
| linear accelerator replaced Co60 equipment because? (3) |
|
Definition
- higher energy with skin sparing effect
-field edges more sharply defined with less pnumbra.
-personell receive less exposure to leakage radiation |
|
|
Term
| 4 main areas of linear accelerator : |
|
Definition
drive stand
gantry
PSA (patient support assembly)
console electronic cabinet
|
|
|
Term
| Rectangular cabinet containing apparatus that drives the linear accelerator= |
|
Definition
|
|
Term
| major components of drive stand: |
|
Definition
magnetron or klystron
circulator
wave guide
cooling system |
|
|
Term
| cathode that provides source of bunched or pulsed electrons injected into accelerator structure = |
|
Definition
|
|
Term
| provides high frequency microwaves = |
|
Definition
|
|
Term
| imultaneously provides high voltage DC pulses to the magnetron or Klystron and electron gun. |
|
Definition
|
|
Term
| Carries microwave power from magnetron or klystron through the accelerator structure.= |
|
Definition
|
|
Term
| accelerates electrons from an electron gun using microwave power from magnetron or klystron.= |
|
Definition
|
|
Term
| magnetron and klystron are two types of ? |
|
Definition
|
|
Term
| device that PRODUCES microwaves |
|
Definition
|
|
Term
| Cylindrical construction w/ central cathode and outer anode w/ resonant cavities. |
|
Definition
|
|
Term
| first step to microwave generation |
|
Definition
cathode heated by inner filament -> electron released by thermionic emissions....
2.The electrons are emitted from the cathode and spiral in the magnetic field. The interaction of the spiraling electrons with the cavities in the anode creates high frequency electromagnetic waves. |
|
|
Term
| The electrons released from cathode are accelerated toward the anode by the action of |
|
Definition
|
|
Term
| microwaves are led to accelerator structure via.. |
|
Definition
|
|
Term
| device that AMPLIFIES microwaves |
|
Definition
|
|
Term
|
Definition
| low power microwave oscillator |
|
|
Term
| first step of microwave amplification |
|
Definition
| cathode heated by hot wire -> electrons released via thermionic emissions |
|
|
Term
| after electrons are release in microwave amplifications.. next step .. |
|
Definition
| .Low level microwaves injected into buncher cavity. setup alternating Electric Field across the gap between left and right cavity walls. |
|
|
Term
| after buncher cavity.. 3rd step? |
|
Definition
|
|
Term
| after velocity modulation, 4th step = |
|
Definition
| Drift Tube → distance along which electrons moving at different velocities merge into discrete bunches. |
|
|
Term
| after drift tube , 5th step = |
|
Definition
| 5.Catcher Cavity → As electrons leave drift tube and traverse catcher cavity gap, microwaves get highly amplified as a result of kinetic energy of bunched electrons. |
|
|
Term
| after catcher cavity, 6th step = |
|
Definition
| microwaves are lead to accelerator structure via wave guide |
|
|
Term
| after wave guide, 7th step = |
|
Definition
| 7.Collector → Residual beam energy that is not converted to microwave power is dissipated as heat in collector cavity. |
|
|
Term
| Once we have microwave accelerating power, we need a place to accelerate those electrons –> |
|
Definition
|
|
Term
| components of x-ray treatment head: (7) |
|
Definition
bending magnet
xray target
primary collimator
beam flattening filter
ion chamber
secondary collimators
slot(s) for wedges, blocks, compensators. |
|
|
Term
| Directs electrons vertically towards a supine patient for an anterior treatment. |
|
Definition
|
|
Term
| magnet bends electrons ____ degrees onto x-ray target (or scattering foil for electron production) |
|
Definition
|
|
Term
| electrons energy is converted into x-ray energy at? |
|
Definition
|
|
Term
| Shapes x-ray beam into cross-sectional dimension. Causes “horns” in the beam at the skin surface. |
|
Definition
|
|
Term
| monitors the beam symmetry in right/left and inferior/superior direction. |
|
Definition
|
|
Term
| Adjusts upper/lower shutter (manual or remote control) |
|
Definition
|
|
Term
| components for electron beam tube head: (8) |
|
Definition
| bending magnet primary collimator scattering foil carrousel ion chamber secondary collimator electron cone applicator aperture or custom block. |
|
|
Term
| Thin and uniform metal used to scatter the pencil thin electron beam. |
|
Definition
|
|
Term
| facilitates the exchange from flattening filter to scattering foil. |
|
Definition
|
|
Term
| attached to treatment head for electron treatment. |
|
Definition
| electron cone or applicator |
|
|
Term
| located at the end of the applicator |
|
Definition
|
|
Term
| functions of controle console? |
|
Definition
monitor units - prescribed dose
mechanical beam parameters |
|
|
Term
one in ceiling and 2 on the side
project small dots or lines that intersect isocenter, help set up patient to predetermined marks. |
|
Definition
|
|
Term
| One end of couch has sturdy plastic square or frame with strings. other end has: |
|
Definition
| removable inserts to allow patient positioning and support devices to be attached. |
|
|
Term
| modulator cabinet contains which 3 things |
|
Definition
Fan control
auxillary power distribution system
primary power distribution system |
|
|
Term
| auxiliary system contains which 3 systems? |
|
Definition
vacuum
pressure
and cooling systems |
|
|
Term
| Record of patients radiation therapy history. |
|
Definition
|
|
Term
| task analysis must contain (6): |
|
Definition
| history and diagnosis Rationale for treatment Treatment Plan Consent Documentation of treatment follow up notes |
|
|
Term
| treatment record contains (6) |
|
Definition
Patient Identification
Signed Prescription
Treatment planning data
treatment field
identifiers daily
treatment record
verification images |
|
|
Term
| what are 5 things on the prescription? |
|
Definition
| dose fractionation treatment technique special immobilization (if necessary) beam modifiers |
|
|
Term
| 2 things in the treatment plan |
|
Definition
| isodose distributions monitor unit calculations |
|
|
Term
| the treatment plan is checked and signed by |
|
Definition
|
|
Term
| each treatment field is assigned .. |
|
Definition
|
|
Term
| each field is described by what 3 things |
|
Definition
| size, angle, beam direction |
|
|
Term
| daily treatment record contains:7 |
|
Definition
treatment number
elapsed days
date
daily and total dose
procedures such as portal imaging
MU given
Dose to critical structures. |
|
|
Term
| documents that verify the correct area is treated |
|
Definition
|
|
Term
|
Definition
Bolus
Compensators
Wedges
Electron cones
internal shielding
electron shields. |
|
|
Term
| treatment techniques: (6) |
|
Definition
AP/PA
POP
tangential
four field box
boost
arc therapy |
|
|
Term
| name things rad therapist must inspect 7: |
|
Definition
treatment unit
treatment accessories
supplies
cleanliness
orderliness
unsafe conditions
lights |
|
|
Term
| modern machines not only treat cancers but control: |
|
Definition
| 1.MLC's 2.Portal imaging (MV) 3.kV imaging 4.Gated therapy treatments. |
|
|
Term
| An image from different resources is used to determine if treatment setup is correct. = |
|
Definition
|
|
Term
| beta aquisition tomography (BAT) is ? |
|
Definition
|
|
Term
| localizes the prostate using 2d images |
|
Definition
|
|
Term
| in ultrasound imaging, obtain ___________ images and compare to a control image determined by dosimetry. |
|
Definition
|
|
Term
| Varian and Elekta are makers of |
|
Definition
|
|
Term
| Allows you to match the persons breathing to the treatment beam. = |
|
Definition
|
|
Term
| delivers as many as 1400 highly pinpointed beams of radiation to control or destroy the tumor. Image-guided cameras locate the tumor's position and remain locked on the target throughout the procedure. |
|
Definition
|
|
Term
cyber knife treatment lasts how long? |
|
Definition
| 2 hrs each spread, for 2 weeks |
|
|
Term
| cyber knife is used for treatments of |
|
Definition
|
|
Term
| used to treat brain tumors with a high dose of radiation therapy in one day. |
|
Definition
|
|
Term
| used in low energy LINAC's |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| higher peak power at 5 mw |
|
Definition
|
|
Term
| produces high frequency microwaves |
|
Definition
|
|
Term
| sends high frequency microwaves to accelorator tube via wave guide |
|
Definition
|
|
Term
| dose rate of accelerator beam varies, so its not possible to rely on |
|
Definition
| elapsed time to control dose delivered to patient |
|
|
Term
| name some status's displayed at the control console: |
|
Definition
standby
prepratory
ready
beam on
interlock
emergency off |
|
|
