Page 68 - 2014 Printable Abstract Book
P. 68
(S1603) Laser CT of BANG3Pro2 polymer gel dosimeter for 3D dosimetry of laser plasma driven VHEE
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dose distributions. Colleen DesRosiers ; Marek Maryanski ; Dino Jaroszynski ; Marc S. Mendonca ; Anna
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Subiel ; Gregor H. Walsh ; Sylvia Cipiccia ; David Reboredo ; Annette Sorensen ; Marie Boyd ; and Vadim
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Moskvin, Indiana University School of Medicine, Indianapolis, IN ; MGS Research, Madison, CT ;
Department of Physics, Scottish Universities Physics Alliance, University of Strathclyde, Glasgow, United
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Kingdom ; and Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde,
4
Glasgow, United Kingdom
Laser Wakefield electron acceleration (LWFA), is a subject of exploration for medical applications in
radiation therapy. LWFA produces femtosecond, as opposed to microsecond pulsed beams produced with
modern medical linear accelerators. Studies suggest that the physical interactions of the particles with
water are greatly impacted by the energy deposition of these high intensity LWFA beams, increasing free
radical production, and, thereby altering the radiobiological response. The dosimetry and radiobiology of
very high energy electrons, > 150 MeV (VHEE) regardless of the production mechanism, is largely
unexplored. We have investigated VHEE dosimetry using a most promising technique of 3D dose mapping,
based on laser CT of polymer gel dosimeters, where laser light scattering on radiation-induced polymer
microparticles suspended in a tissue-equivalent gel generates optical density contrast capable of
measuring the dose in 3D with 1-2% uncertainty and 0.5 mm spatial resolution. Recently, this technique
has been successfully applied to proton therapy fields, and, most interestingly, it was established that new
modified formulations of this dosimeter, called BANG3Pro2, were capable of detecting regions of higher
LET, and potentially mapping the LET in three dimensions. The main result we are reporting here is that
from our preliminary results it looks plausible that the laser plasma driven VHEE beams may generate
broad regions of very high density of free-radical formation, that are potentially radiobiologically
equivalent to high-LET. We believe that temporal aspects of energy deposition and migration leading to
the formation of free-radicals may make it possible for the polymer gel dosimeter to detect, and possibly
map in 3D, the regions of high ionization density that may be produced by these fields in a tissue-
equivalent medium. Our MC simulation predicts an increase in LET for these particles as compared with
electrons in the clinical range (6-30 MeV) and if one includes the time dependent component could result
in an even greater LET than predicted.
(S1604) The biological effects of high energy electrons (VHEE, 100-150MeV) produced by a laser-plasma
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wakefield accelerator on tumour cells. Annette Sorensen ; P. Farrell ; A. Subiel ; G. Welsh ; X. Yang ; M.
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Wiggins ; V. Moskvin ; C. DesRosiers ; M. Mendonca ; D. Jaroszynski ; and M. Boyd SIPBS, University of
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Strathclyde, Glasgow, United Kingdom ; Department of Physics, University of Strathclyde, Glasgow,
2
United Kingdom ; and Department of Radiation Oncology, Indiana University School of Medicine,
Indianapolis, IN
3
The use of electrons with energies over 100 MeV as a treatment modality for cancer was first proposed
in 2000 by DesRosiers et al. However, to date, studies that have been undertaken to investigate this form
of radiotherapy have mainly been theoretical due to a lack of readily available VHEE accelerators. These
studies have demonstrated deeper tissue penetration and energy deposition arising compared with X-ray
photons. The rapid developments in ultra-compact laser-plasma wakefield accelerators (LWFAs) have the
potential to provide an alternative source of VHEE for radiotherapy. The ALPHA-X beam line at the
University of Strathclyde utilises laser plasma accelerators for the production of ultra-short duration, high
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1
2
1
3
dose distributions. Colleen DesRosiers ; Marek Maryanski ; Dino Jaroszynski ; Marc S. Mendonca ; Anna
3
4
3
3
4
3
Subiel ; Gregor H. Walsh ; Sylvia Cipiccia ; David Reboredo ; Annette Sorensen ; Marie Boyd ; and Vadim
1
1
2
Moskvin, Indiana University School of Medicine, Indianapolis, IN ; MGS Research, Madison, CT ;
Department of Physics, Scottish Universities Physics Alliance, University of Strathclyde, Glasgow, United
3
Kingdom ; and Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde,
4
Glasgow, United Kingdom
Laser Wakefield electron acceleration (LWFA), is a subject of exploration for medical applications in
radiation therapy. LWFA produces femtosecond, as opposed to microsecond pulsed beams produced with
modern medical linear accelerators. Studies suggest that the physical interactions of the particles with
water are greatly impacted by the energy deposition of these high intensity LWFA beams, increasing free
radical production, and, thereby altering the radiobiological response. The dosimetry and radiobiology of
very high energy electrons, > 150 MeV (VHEE) regardless of the production mechanism, is largely
unexplored. We have investigated VHEE dosimetry using a most promising technique of 3D dose mapping,
based on laser CT of polymer gel dosimeters, where laser light scattering on radiation-induced polymer
microparticles suspended in a tissue-equivalent gel generates optical density contrast capable of
measuring the dose in 3D with 1-2% uncertainty and 0.5 mm spatial resolution. Recently, this technique
has been successfully applied to proton therapy fields, and, most interestingly, it was established that new
modified formulations of this dosimeter, called BANG3Pro2, were capable of detecting regions of higher
LET, and potentially mapping the LET in three dimensions. The main result we are reporting here is that
from our preliminary results it looks plausible that the laser plasma driven VHEE beams may generate
broad regions of very high density of free-radical formation, that are potentially radiobiologically
equivalent to high-LET. We believe that temporal aspects of energy deposition and migration leading to
the formation of free-radicals may make it possible for the polymer gel dosimeter to detect, and possibly
map in 3D, the regions of high ionization density that may be produced by these fields in a tissue-
equivalent medium. Our MC simulation predicts an increase in LET for these particles as compared with
electrons in the clinical range (6-30 MeV) and if one includes the time dependent component could result
in an even greater LET than predicted.
(S1604) The biological effects of high energy electrons (VHEE, 100-150MeV) produced by a laser-plasma
2
2
2
2
1
wakefield accelerator on tumour cells. Annette Sorensen ; P. Farrell ; A. Subiel ; G. Welsh ; X. Yang ; M.
3
3
3
1
2
2
Wiggins ; V. Moskvin ; C. DesRosiers ; M. Mendonca ; D. Jaroszynski ; and M. Boyd SIPBS, University of
1
Strathclyde, Glasgow, United Kingdom ; Department of Physics, University of Strathclyde, Glasgow,
2
United Kingdom ; and Department of Radiation Oncology, Indiana University School of Medicine,
Indianapolis, IN
3
The use of electrons with energies over 100 MeV as a treatment modality for cancer was first proposed
in 2000 by DesRosiers et al. However, to date, studies that have been undertaken to investigate this form
of radiotherapy have mainly been theoretical due to a lack of readily available VHEE accelerators. These
studies have demonstrated deeper tissue penetration and energy deposition arising compared with X-ray
photons. The rapid developments in ultra-compact laser-plasma wakefield accelerators (LWFAs) have the
potential to provide an alternative source of VHEE for radiotherapy. The ALPHA-X beam line at the
University of Strathclyde utilises laser plasma accelerators for the production of ultra-short duration, high
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