Objective: This article presents a set of dosimetric measurements describing the properties of brass mesh (Whiting and Davis, Attleboro Falls, MA) under megavoltage photon irradiation conditions, with particular relevance to its use in breast radiotherapy.
Methods: The effectiveness of brass mesh as a bolus material was investigated using 6-, 15- and 6-MV flattening filter-free photon beams. The effect on dose build-up at the entrance surface, build-down at the beam-exit surface, dose with surface entrance obliquity, beam profiles, penumbra and percentage depth doses were investigated.
This work describes an experimental verification of the two-photon dose calculation engines available on the Helax-TMS (version 6.1) commercial radiotherapy treatment planning system. The performance of the pencil beam convolution and the collapsed cone superposition algorithms was examined for 4, 6, 15 MV beams, under a range of clinically relevant irradiation geometries.
View Article and Find Full Text PDFFifteen consecutive patients had standard treatment plans generated using our departmental protocol and two further plans produced using either an asymmetric, or MLC shaped additional field, from each tangential direction. The mean percentage of the PTV receiving over 107% of the isocentre dose was 19.8% for the standard planned patients (95% confidence interval 12.
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