Isocentric
• c = 10 x 10 cm²
Dose per MU formalisms:
factor-based dose calculations
Reference normalisation conditions
Fixed SSD
c = 10 x 10 cm²
ref
Field Size at isocenter
• d
ref
= 10 cm
• SSD = SAD - d
ref
Tissue phantom ratio
TPR(c,d)
ref
Field size at surface
d
ref
= 10 cm
SSD = SAD
Relative depth dose
RDD(s,z)
SAD
SSD=SAD
c
ref
(
)
[
]
MU cGy
M
d cD
SAD ;
,
ref
ref
(
)
[
]
MU cGy
M
d cD
SSD ;
,
ref
ref
d
ref
d
ref
c
ref