% 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{Shukla:165992,
      author       = {B. Shukla and C. K. Spindeldreier$^*$ and O. Schrenk$^*$
                      and A. C. Bakenecker$^*$ and S. Klüter and I. Kawrakow and
                      A. Runz$^*$ and L. Burigo$^*$ and C. P. Karger$^*$ and K.-S.
                      Greilich$^*$ and A. Pfaffenberger$^*$},
      title        = {{D}osimetry in magnetic fields with dedicated
                      {MR}-compatible ionization chambers.},
      journal      = {Physica medica},
      volume       = {80},
      issn         = {1120-1797},
      address      = {Amsterdam},
      publisher    = {Elsevier},
      reportid     = {DKFZ-2020-02531},
      pages        = {259 - 266},
      year         = {2020},
      note         = {#EA:E040#LA:E040#},
      abstract     = {MR-integrated radiotherapy requires suitable dosimetry
                      detectors to be used in magnetic fields. This study
                      investigates the feasibility of using dedicated
                      MR-compatible ionization chambers at MR-integrated
                      radiotherapy devices. MR-compatible ionization chambers
                      (Exradin A19MR, A1SLMR, A26MR, A28MR) were precisely modeled
                      and their relative response in a 6MV treatment beam in the
                      presence of a magnetic field was simulated using EGSnrc.
                      Monte Carlo simulations were carried out with the magnetic
                      field in three orientations: the magnetic field aligned
                      perpendicular to the chamber and beam axis (transverse
                      orientation), the magnetic field parallel to the chamber as
                      well as parallel to the beam axis. Monte Carlo simulation
                      results were validated with measurements using an
                      electromagnet with magnetic field strength upto 1.1 T with
                      the chambers in transverse orientation. The measurements and
                      simulation results were in good agreement, except for the
                      A26MR ionization chamber in transverse orientation. The
                      maximum increase in response of the ionization chambers
                      observed was $8.6\%$ for the transverse orientation. No
                      appreciable change in chamber response due to the magnetic
                      field was observed for the magnetic field parallel to the
                      ionization chamber and parallel to the photon beam. Polarity
                      and recombination correction factor were experimentally
                      investigated in the transverse orientation. The polarity
                      effect and recombination effect were not altered by a
                      magnetic field. This study further investigates the response
                      of the ionization chambers as a function of the chambers'
                      rotation around their longitudinal axis. A variation in
                      response was observed when the chamber was not rotationally
                      symmetric, which was independent of the magnetic field.},
      cin          = {E040},
      ddc          = {610},
      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:33220650},
      doi          = {10.1016/j.ejmp.2020.10.021},
      url          = {https://inrepo02.dkfz.de/record/165992},
}