TY  - JOUR
AU  - Schwahofer, Andrea
AU  - Mann, P.
AU  - Spindeldreier, C. K.
AU  - Karger, C. P.
TI  - On the feasibility of absolute 3D dosimetry using LiF thermoluminescence detectors and polymer gels on a 0.35T MR-LINAC.
JO  - Physics in medicine and biology
VL  - 65
IS  - 21
SN  - 1361-6560
CY  - Bristol
PB  - IOP Publ.
M1  - DKFZ-2020-02301
SP  - 215002
PY  - 2020
N1  - #EA:E040#LA:E040#
AB  - As shown in our previous study, highly accurate absolute dosimetry in 3D is feasible by combining polymer gels (PG) with thermoluminescence dosimetry (TLD). In this setup, the thermoluminescence (TL)-based point dose information is used to renormalize the PG. This new PG-TLD reference system is now extended to measurements in magnetic fields.Experiments were carried out on a conventional 6 MV linear accelerator (LINAC) and a 6 MV 0.35 T magnetic resonance (MR)-LINAC. Signal stability of TLD600 and TLD700 was examined without and with magnetic field. Afterwards, the combination of PAGAT PG and TL detectors was employed within a cylindrical phantom in presence of the magnetic field. Two scenarios were tested: (I) an air-filled phantom and (II) a water-filled phantom. For each scenario, two plans were irradiated: (a) opposed beams with a field size of 10 × 10 cm2 and (b) a 3D conformal plan assuring homogeneous target coverage using three equally distributed coplanar beams.Mean relative uncertainty of TL calibration reproducibility for TLD600/TLD700 was 0.49
LB  - PUB:(DE-HGF)16
C6  - pmid:33104524
DO  - DOI:10.1088/1361-6560/aba6d7
UR  - https://inrepo02.dkfz.de/record/164172
ER  -