CPB Budapest 2017

718 / 1609

Forward Planning / Optimization
Geometrical “ Optimisation”, GO
b
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2
 The dwell time of the source at a dwell position is
inversely proportional to the dose contribution of
neighboring source dwell positions.
 Points a, b, c, … are source dwell positions (SDPs).
...
1 1 1
2
3
3
2
2
2
2
1
1 







 








 








 
b b b
b
r
T
r
T
r
T D









b
b D
T
1
: If D b large 
Tb small
Implant /
Catheters
Ti equal to 1 at start, iteratively calculated
until nothing changes anymore.
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