2122-2123 / 3107
Blurring
→
‘unsharpened’ dose distribution
•
Averaging or smearing of the dose
distribution near beam edges
→
increased beam penumbra
→
loss in
dose homogeneity and conformity
•
The amount of blurring depends
on the amplitude and the
25%
characteristics of the motion and on
the “sharpness” (inhomogeneity) of
the static dose distribution
•
Worst for IMR/PT
→
margin
reduction
McCarter&Beckam, PMB (45) 2001