Počet záznamů: 1  

Measurement of stray neutron doses inside the treatment room from a proton pencil beam scanning system

  1. 1. 0488861 - UJF-V 2018 RIV GB eng J - Článek v odborném periodiku
    Mojzeszek, N. - Farah, J. - Klodowska, M. - Ploc, Ondřej - Stolarczyk, L. - Waligorski, M. P. R. - Olko, P.
    Measurement of stray neutron doses inside the treatment room from a proton pencil beam scanning system.
    Physica Medica. Roč. 34, č. 2 (2017), s. 80-84 ISSN 1120-1797
    Institucionální podpora: RVO:61389005
    Klíčová slova: secondary neutrons * proton therapy * pencil beam scanning systtems * out-of-field doses * stray neutron doses * TEPC
    Kód oboru RIV: FP - Ostatní lékařské obory
    Obor OECD: Radiology, nuclear medicine and medical imaging
    Impakt faktor: 2.240, rok: 2017

    Purpose: To measure the environmental doses from stray neutrons in the vicinity of a solid slab phantom as a function of beam energy, field size and modulation width, using the proton pencil beam scanning (PBS) technique.

    Method: Measurements were carried out using two extended range WENDI-II rem-counters and three tissue equivalent proportional counters. Detectors were suitably placed at different distances around the RW3 slab phantom. Beam irradiation parameters were varied to cover the clinical ranges of proton beam energies (100-220 MeV), field sizes ((2 x 2)-(20 x 20) cm(2)) and modulation widths (0-15 cm).

    Results: For pristine proton peak irradiations, large variations of neutron H*(10)/D were observed with changes in beam energy and field size, while these were less dependent on modulation widths. H*(10)/ D for pristine proton pencil beams varied between 0.04 mu Sv Gy(-1) at beam energy 100 MeV and a (2 x 2) cm(2) field at 2.25 m distance and 90 degrees angle with respect to the beam axis, and 72.3 mu Sv Gy(-1) at beam energy 200 MeV and a (20 x 20) cm(2) field at 1 m distance along the beam axis.

    Conclusions: The obtained results will be useful in benchmarking Monte Carlo calculations of proton radiotherapy in PBS mode and in estimating the exposure to stray radiation of the patient. Such estimates may be facilitated by the obtained best-fitted simple analytical formulae relating the stray neutron doses at points of interest with beam irradiation parameters.
    Trvalý link: http://hdl.handle.net/11104/0283381