IAEA TECDOC 1583 Flashcards
what is this TECDOC specific to?
commissioning of TPS for typical EBRT
what does the report call beam modelling
beam fitting
ie measuring PDD etc for each beam energy
-measurements must be done in water phantom
3 phantoms for commissioning tests
-CT phantom
-slab geometry phantom
-anthropomorphic phantom
what is CT phantom used for
o Check of CT number to relative electron density (RED) conversion
o Beam geometry assessments
o Digitally reconstructed radiograph (DRR) generation
o Multiplanar reconstruction
what is slab geometry phantom used for?
o Water/tissue equivalent material
o Possibility for film dosimetry
o Check of corrections for inhomogeneous geometries
what is anthropomorphic phantom used for?
o Dosimetric measurements of typical or special treatment techniques
CIRS thorax phantom
thorax shaped phantom with interchangeable inserts
-inserts can accomodate ion chambers
-spaces for film
permissible error for CT # vs TPS
within 20 CT numbers
Cases that are tested
-oblique incidence
-blocked fields
-not enough scatter material
what does QUASAR MLC phantom do?
-addresses nondosimetric, beam geometry, and beam imaging features of TPS
-physical simulation of beam with MLC leaf locations
-simulates couch and gantry rotations
-E2E testing of beam integrity
-for example- makes DRRs from CT images with obliwue couch and gantry angle
steps in QUASAR MLC tests
-CT scanning
-coordinate system registration
-image acquisition and transfer
-beam display
-multiplanar CT image reconstuction
-DRRs
-portal imaging
multi-purpose QUASAR phantom test
-contour the inserts and compare measured volume to actual volume
-deliver a beam to a volume and get DVH- confirm TPS
-CT number to RED conversions
-E2E test with phantom- dose measurement with ion chamber in phantom n
What is TECDOC 1583 about
commissioning of radiotherapy TPS for typical EBRT
