breast cancer : radiation therapy process Flashcards
(5 cards)
Patient Positioning Difficulties
CT: APERTURE SIZE
-arm position - mobility post surgery and if it fits through the bore
-breast board tilt
-field of view - not encompass the whole breast
Possible Positioning Uncertainties:
skin marks
-may shift TO DEEPER TISSUE
-the thickness in set up lines may cause variations in field position
-variation of remarking if faded
Positioning Uncertainties:
internal motion - intrafractional
Respiratory
cardiac
changes in size and shape of organ
techniques used to decrease mean heart dose
DIBH
prone RT
proton therapy
Proton Therapy
lower exit dose due to the sharp dose gradient fall off