% 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{Schorling:303447,
author = {C. Schorling$^*$ and E. Rauth$^*$ and C. Stengl$^*$ and J.
Seco$^*$},
title = {{E}xperimental investigation of oxygen diffusion in the
peak and valley region of minibeam patterns during x-ray
irradiation.},
journal = {Medical physics},
volume = {52},
number = {8},
issn = {0094-2405},
address = {Hoboken, NJ},
publisher = {Wiley},
reportid = {DKFZ-2025-01660},
pages = {e17999},
year = {2025},
note = {#EA:E041#LA:E041#},
abstract = {Minibeam radiotherapy has demonstrated its potential to
reduce normal tissue toxicity while maintaining tumor
control. However, the underlying mechanisms behind this
phenomenon remain unknown. Recent theoretical studies
suggest a dose surrogate by diffusion of H 2 O 2 ${\rm
H}_2{\rm O}_2$ into the valley regions.The aim of this study
is to experimentally investigate oxygen depletion and
diffusion upon minibeam (MB) irradiation.A 3D-printed water
phantom with four sensors was developed to enable the
real-time, simultaneous measurement of oxygen concentration
in the peak and valley. Water with 0\%-11\% O 2 ${\rm O}_2$
and 0.1\%/5.0\% CO 2 ${\rm CO}_2$ was irradiated with broad
beam (BB) and MB characterized by peak and valley widths of
2 mm × $\times$ 2 mm and 0.5 mm × $\times$ 2 mm. The
depletion was further compared in other chemical
environments.The oxygen depletion rates per dose in hypoxic
water in the valley regions were found to be 3-7 times
higher compared to the peaks or BB. This observation was
found to be independent of oxygen concentration above 2 \%,
indicating oxygen depletion saturation. For MB, diffusion
between peaks and valleys was observed. After a certain
period, an equilibrium between diffusion and dose rate
differences was established. Glutathione and HEPES as a
medium increased the depletion further and distinguished MB
from BB.A novel way of simultaneously measuring oxygen in
the peak and valley of the MB dose pattern was introduced.
The observed oxygen depletion saturation and diffusion
between the peaks and valleys suggest the importance of
oxygen in spatially fractionated radiotherapy studies, which
is even greater for 5 mM glutathione compared to water.},
keywords = {Oxygen: metabolism / Diffusion / X-Rays / Phantoms, Imaging
/ Water: chemistry / minibeam irradiation (Other) / oxygen
depletion measurements (Other) / spatial fractionation
(Other) / Oxygen (NLM Chemicals) / Water (NLM Chemicals)},
cin = {E041 / E040},
ddc = {610},
cid = {I:(DE-He78)E041-20160331 / I:(DE-He78)E040-20160331},
pnm = {315 - Bildgebung und Radioonkologie (POF4-315)},
pid = {G:(DE-HGF)POF4-315},
typ = {PUB:(DE-HGF)16},
pubmed = {pmid:40781834},
pmc = {pmc:PMC12334874},
doi = {10.1002/mp.17999},
url = {https://inrepo02.dkfz.de/record/303447},
}