In:
Journal of Instrumentation, IOP Publishing, Vol. 17, No. 09 ( 2022-09-01), p. P09005-
Abstract:
Radiotherapy (RT) is a fundamental tool in cancer
treatment. Recent technological advances improved considerably radiotherapy techniques, allowing to obtain more precise, effective
and most importantly safer treatments. However, RT is not without risks. Ionizing radiation also injures healthy cells, and there is a
limit to the amount of radiation an area of the body can safely receive over the course of a lifetime. A new delivery method, called
FLASH radiotherapy (FLASH-RT) has shown very promising results in in vivo studies, where a significant increase in healthy
tissue sparing (FLASH effect) was observed. FLASH-RT consists in delivering the ionizing radiation therapy at dose rates much higher
than the ones used in conventional radiotherapy (CONV-RT). Because of the novelty of this method, every aspect of FLASH-RT is under
study, such as how the FLASH effect depends on therapy delivery parameters and what exactly are the underlining biological
mechanisms. Nonetheless, dosimetry presents a challenge to overcome. The high dose rates cause significant saturation problems
which render standard dosimetric equipment inadequate. Therefore, the development of online (active) dosimeters is a priority. In the
short term this technology enables more efficient measurements in the experimental context, since it gives immediate feedback. In the
long term it provides the basis for future studies on dosimetry in clinical practice.
In this work we show the construction and characterization of online FLASH dosimeters based on scintillator materials used in
integrating-mode. A GEANT4 based Monte Carlo simulation code is specifically developed to calculate the medium-equivalence
correction. The simulation is validated with experimental measurements obtained with a full-fledged FLASH linear accelerator,
which produces electron pulsed beams at very high dose per pulse. Measurements suggest that the proposed dosimeters have a
linear response in a wide range of dose per pulse values up to 6 Gy/p, while moderate saturation can be observed up to
12.5 Gy/p.
Type of Medium:
Online Resource
ISSN:
1748-0221
DOI:
10.1088/1748-0221/17/09/P09005
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
2022
detail.hit.zdb_id:
2235672-1
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