Advanced Physics for Brachytherapy 2018

Inverse Planning – using HIPO



~

M

kASDP

N

N

i j

2

i jkl

d       ) , , ( w t r f





feasible

=

(x)

d Sxb

1 =  = m

fw f m m =

Minimise

lk K lk k ,

=

=

k

1

l

1

Hybrid Inverse Planning and Optimization Engine HIPO

The MINLP problem is solved by HIPO by a hybrid approach :

• A heuristic combining SA & scoring for the binary part b • A quasi-Newton for the continuous part t = x² ( optimisation, L-BFGS ) • Make use of a non-linear description of the transition function Θ

= .

+ ( . )

(1) Karabis A, Giannouli S, Baltas D: Radiotherapy & Oncology , 76, 29, 2005 (2) Karabis A, Belotti P, Baltas D: WC 2009