2370-2371 / 3107
Open beams:
D(z,c)=D
R
*MU*O
R
(c)*TPR(z,c)
MU
is the number of monitor units
D
R
is the dose per MU at a reference depth on the beam axis
under reference conditions
D(z,c) is the dose under treatment conditions and at a depth z and
field size of c
O
R
(c) is the out-put ratio, i.e. the scatter factor.
TPR(z,c) is tissue-phantom ratio, i.e. the ratio of dose at depth z to that
of the reference depth.
·
·
MU calculations
D(z,c)
D
R
*O
R
(c)*TPR(z,c)
MU=
·