TY  - JOUR
AU  - Nabha, Racell
AU  - De Saint-Hubert, Marijke
AU  - Marichal, Joachim
AU  - Esser, Johannes
AU  - Van Hoey, Olivier
AU  - Bäumer, Christian
AU  - Verbeek, Nico
AU  - Struelens, Lara
AU  - Sterpin, Edmond
AU  - Tabury, Kevin
AU  - Marek, Lukas
AU  - Granja, Carlos
AU  - Timmermann, Beate
AU  - Vanhavere, Filip
TI  - Biophysical characterization of collimated and uncollimated fields in pencil beam scanning proton therapy.
JO  - Physics in medicine and biology
VL  - 68
IS  - 6
SN  - 0031-9155
CY  - Bristol
PB  - IOP Publ.
M1  - DKFZ-2023-00543
SP  - 064001
PY  - 2023
AB  - Objective. The lateral dose fall-off in proton pencil beam scanning (PBS) technique remains the preferred choice for sparing adjacent organs at risk as opposed to the distal edge due to the proton range uncertainties and potentially high relative biological effectiveness. However, because of the substantial spot size along with the scattering in the air and in the patient, the lateral penumbra in PBS can be degraded. Combining PBS with an aperture can result in a sharper dose fall-off, particularly for shallow targets.Approach. The aim of this work was to characterize the radiation fields produced by collimated and uncollimated 100 and 140 MeV proton beams, using Monte Carlo simulations and measurements with a MiniPIX-Timepix detector. The dose and the linear energy transfer (LET) were then coupled with publishedin silicobiophysical models to elucidate the potential biological effects of collimated and uncollimated fields.Main results. Combining an aperture with PBS reduced the absorbed dose in the lateral fall-off and out-of-field by 60
KW  - Humans
KW  - Proton Therapy: methods
KW  - Protons
KW  - Radiotherapy Planning, Computer-Assisted: methods
KW  - Radiotherapy Dosage
KW  - Monte Carlo Method
KW  - DNA damage (Other)
KW  - Timepix (Other)
KW  - aperture (Other)
KW  - collimation (Other)
KW  - pencil beam scanning (Other)
KW  - proton therapy (Other)
KW  - Protons (NLM Chemicals)
LB  - PUB:(DE-HGF)16
C6  - pmid:36821866
DO  - DOI:10.1088/1361-6560/acbe8d
UR  - https://inrepo02.dkfz.de/record/274337
ER  -