Dose Course 2018_Flipping book

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In favour of using

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Andreo

❑ Current clinical experience is mostly based on dose-to-water, hence the use of , allows direct compliance with previous clinical experience and with treatment planning based on analytical algorithms. o Doses reported in clinical trials, and therapeutic and normal-tissue tolerance criteria, are based on , . ❑ Reference dosimetry (beam calibration) of accelerators relies on dosimetry protocols yielding a reference absorbed dose to water , , , which is used to normalize the output of the TPS. o This is the reference quantity at the clinic, irrespective of the type of calibration coefficient of the ionization chamber used, either in terms of absorbed dose-to-water or air-kerma. ❑ MCTP relies on the assumption that the codes used are ‘ accurate ’, irrespective of the sometimes crude approximations made in the physical models of these systems, often simpler than those in general MC codes.

From P. Andreo, "Dose to 'water-like' media or dose to tissue in MV photons radiotherapy treatment planning: still a matter of debate," Phys. Med. Biol. 60, 309-337 (2015)

Dublin 2018