%0 Journal Article
%A Stengl, Christina
%A Arbes, Eric
%A Thai, Long-Yang Jan
%A Echner, Gernot
%A Vedelago, José
%A Jansen, Jeannette
%A Jäkel, Oliver
%A Seco, Joao
%T Development and characterization of a versatile mini-beam collimator for pre-clinical photon beam irradiation.
%J Medical physics
%V 50
%N 8
%@ 0094-2405
%C College Park, Md.
%I AAPM
%M DKFZ-2023-00912
%P 5222-5237
%D 2023
%Z #EA:E040#LA:E040#LA:E041# / 2023 Aug;50(8):5222-5237
%X Interest in spatial fractionation radiotherapy has exponentially increased over the last decade as a significant reduction of healthy tissue toxicity was observed by mini-beam irradiation. Published studies, however, mostly use rigid mini-beam collimators dedicated to their exact experimental arrangement such that changing the setup or testing new mini-beam collimator configurations becomes challenging and expensive.In this work, a versatile, low-cost mini-beam collimator was designed and manufactured for pre-clinical applications with X-ray beams. The mini-beam collimator enables variability of the full width at half maximum (FWHM), the center-to-center distance (ctc), the peak-to-valley dose ratio (PVDR), and the source-to-collimator distance (SCD).The mini-beam collimator is an in-house development, which was constructed of 10 ×  40 mm2 tungsten or brass plates. These metal plates were combined with 3D-printed plastic plates that can be stacked together in the desired order. A standard X-ray source was used for the dosimetric characterization of four different configurations of the collimator, including a combination of plastic plates of 0.5, 1, or 2 mm width, assembled with 1 or 2 mm thick metal plates. Irradiations were done at three different SCDs for characterizing the performance of the collimator. For the SCDs closer to the radiation source, the plastic plates were 3D-printed with a dedicated angle to compensate for the X-ray beam divergence, making it possible to study ultra-high dose rates of around 40 Gy/s. All dosimetric quantifications were performed using EBT-XD films. Additionally, in vitro studies with H460 cells were carried out.Characteristic mini-beam dose distributions were obtained with the developed collimator using a conventional X-ray source. With the exchangeable 3D-printed plates, FWHM and ctc from 0.52 to 2.11 mm, and from 1.77 to 4.61 mm were achieved, with uncertainties ranging from 0.01
%K 3D printing (Other)
%K dosimetry (Other)
%K mini-beam collimator (Other)
%K spatial fractionation (Other)
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid:37145971
%R 10.1002/mp.16432
%U https://inrepo02.dkfz.de/record/275924