Image Guided Radiotherapy Flashcards
In general most tumours are radio resistant if there not in the?
Treatment beam
IGRT is?
External beam radiation therapy with positional verification using imaging prior to each fraction
IGRT is not limited to?
3DCRT, IMRT, VMAT, radiosurgery, stereotactic
IGRT is used for ?
Positional verification
What is a systematic error?
Deviation that occurs in the same direction and of a similiar magnitude for each fraction
What is a random error?
Is a deviation that can vary in direction and magnitude during the treatment
How do you correct for error?
Margins
GTV-disease we can see
CTV-microscopic disease
PTV-where you treat
Is MRI better than CT imaging for certain things?
Yes MRI shows better delineation of soft tissue and water!
What movements can we predict?
Bladder filling minute to minute
Respiration
Heart beat both second to second
What movements can’t we predict?
Skin motion day to day
Prostate motion hour to hour
Neck flex
Peristalsis second to second
What is interfractional?
Varies day to day
What is intrafraxtional?
Movement during treatment
IGRT detects what?
Positional errors weight loss substantial organ deformation changes in respiratory motion
Soft tissue matching?
Is matching prostate rectum bladder
Skin render?
Outside representation of the patient
