% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@ARTICLE{Hoffmans:154497,
author = {D. Hoffmans and N. I. Niebuhr$^*$ and O. Bohoudi and A.
Pfaffenberger$^*$ and M. A. Palacios},
title = {{A}n end-to-end test for {MR}-guided online adaptive
radiotherapy.},
journal = {Physics in medicine and biology},
volume = {65},
number = {12},
issn = {1361-6560},
address = {Bristol},
publisher = {IOP Publ.},
reportid = {DKFZ-2020-00819},
pages = {Article number 125012},
year = {2020},
note = {Volume 65, Issue 12, 21 June 2020, Article number 125012},
abstract = {In the evolving field of adaptive MR guided radiotherapy,
the need for dedicated procedures for acceptance and quality
assurance is increasing. Research has been devoted to MR
compatible dosimeters and phantoms, but to date no
end-to-end test has been presented that covers an MRgRT
workflow. Such an end-to-end test should comprise each step
of the workflow and include all associated uncertainties.
The purpose of this study was to investigate the usability
of an anthropomorphic deformable and multimodal pelvis
(ADAM-pelvis) phantom in combination with film dosimetry for
end-to-end testing of an MRgRT adaptive workflow. The
ADAM-pelvis phantom included surrogates for muscle tissue,
adipose and bone, as well as deformable silicone organs
mimicking a prostate patient. At the interfaces of the
critical structures (bladder and rectum), small pieces of
GafChromic EBT3 films were placed to measure delivered dose.
Pre-treatment MR imaging of the phantom was used to
delineate the prostate, rectum and bladder and to generate a
treatment plan to deliver 2 Gy to the prostate. Electron
density (ED) map from CT imaging was used for dose
calculation after deformable image registration (DIR) to the
pre-treatment MR scan. At each fraction, bladder- and rectum
filling was varied and a new adapted plan was generated.
Dose calculation was performed using both a DIR-based ED map
and a CT-based ED map after acquisition of a new CT scan of
the phantom at each fraction. Dose calculations were
performed taking into account the magnetic field. A good
agreement between measured and calculated dose was found
using both, the CT-derived and the DIR-based ED map $(2.0\%$
and $2.8\%$ dose difference, respectively). The gamma index
pass-rate $(3\%$ / 2 mm) varied from $96.4\%$ to $100\%.The$
ADAM-pelvis phantom was suitable for end-to-end testing in
MR-guided radiotherapy and a very good agreement with the
calculated dose was achieved.},
cin = {E040},
ddc = {530},
cid = {I:(DE-He78)E040-20160331},
pnm = {315 - Imaging and radiooncology (POF3-315)},
pid = {G:(DE-HGF)POF3-315},
typ = {PUB:(DE-HGF)16},
pubmed = {pmid:32294637},
doi = {10.1088/1361-6560/ab8955},
url = {https://inrepo02.dkfz.de/record/154497},
}