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High grade glioma - PTV
Use the
‘
Margin Recipe
’
- PTV = 2.5
Σ
+ 0.7
σ
Measure the standard deviations in
each department
Our dept – PTV margin = 0.3 cm with
IGRT
Systematic errors (mm)
Gaussian
Σ
doctor
0.0
0.0
0.0
Σ
motion
0.0
0.0
0.0
Σ
transfer
0.1
0.1
0.1
Σ
set-up
0.25
0.25
0.25
Σ
(combined)
0.3
0.3
0.3
Linear
b
0.0
0.0
0.0
a
0.0
0.0
0.0
Treatment Execution errors
Gaussian
σ
set-up
0.3
0.3
0.3
σ
motion(target shape)
0.0
0.0
0.0
σ
p
5.5
5.5
5.5
σ
(combined)
5.5
5.5
5.5
Planning parameter (
β)
1.64
1.64
1.64
Semi-sides
systematic
0.7
0.7
0.7
execution
9.0
9.0
9.0
breathing
0.0
0.0
0.0
scalar (a-
βσ
p)
-9.0
-9.0
-9.0
Total CTV-PTV margin
0.7
0.7
0.7