TY  - JOUR
AU  - Wieser, Hans-Peter
AU  - Hennig, P.
AU  - Wahl, N.
AU  - Bangert, Mark
TI  - Analytical probabilistic modeling of RBE-weighted dose for ion therapy.
JO  - Physics in medicine and biology
VL  - 62
IS  - 23
SN  - 1361-6560
CY  - Bristol
PB  - IOP Publ.
M1  - DKFZ-2017-06140
SP  - 8959-8982
PY  - 2017
AB  - Particle therapy is especially prone to uncertainties. This issue is usually addressed with uncertainty quantification and minimization techniques based on scenario sampling. For proton therapy, however, it was recently shown that it is also possible to use closed-form computations based on analytical probabilistic modeling (APM) for this purpose. APM yields unique features compared to sampling-based approaches, motivating further research in this context. This paper demonstrates the application of APM for intensity-modulated carbon ion therapy to quantify the influence of setup and range uncertainties on the RBE-weighted dose. In particular, we derive analytical forms for the nonlinear computations of the expectation value and variance of the RBE-weighted dose by propagating linearly correlated Gaussian input uncertainties through a pencil beam dose calculation algorithm. Both exact and approximation formulas are presented for the expectation value and variance of the RBE-weighted dose and are subsequently studied in-depth for a one-dimensional carbon ion spread-out Bragg peak. With V and B being the number of voxels and pencil beams, respectively, the proposed approximations induce only a marginal loss of accuracy while lowering the computational complexity from order [Formula: see text] to [Formula: see text] for the expectation value and from [Formula: see text] to [Formula: see text] for the variance of the RBE-weighted dose. Moreover, we evaluated the approximated calculation of the expectation value and standard deviation of the RBE-weighted dose in combination with a probabilistic effect-based optimization on three patient cases considering carbon ions as radiation modality against sampled references. The resulting global γ-pass rates (2 mm,2
LB  - PUB:(DE-HGF)16
C6  - pmid:28980974
DO  - DOI:10.1088/1361-6560/aa915d
UR  - https://inrepo02.dkfz.de/record/131073
ER  -