Magnetization transfer imaging for polymer gel dosimetry
(2002) In Physics in Medicine and Biology 47(11). p.1881-1890- Abstract
- Off-resonance RF pre-saturation was used to obtain contrast in MRI images of polymer gel dosimeters irradiated to doses up to 50 Gy. Two different polymer gel dosimeters composed of 2-hydroxyethyl-acryl ate or methacrylic acid monomers mixed with N, N'-methylene-bisacrylamide (BIS), dispersed in an aqueous gelatin matrix were evaluated. Radiation-induced polymerization of the co-monomers generates a fast-relaxing insoluble polymer. Saturation of the polymer using off-resonance Gaussian RF pulses prior to a spin-echo read-out with a short echo time leads to contrast that is dependent on the absorbed dose. This contrast is attributed to magnetization transfer (MT) between free water and the polymer, and direct saturation of water was found... (More)
- Off-resonance RF pre-saturation was used to obtain contrast in MRI images of polymer gel dosimeters irradiated to doses up to 50 Gy. Two different polymer gel dosimeters composed of 2-hydroxyethyl-acryl ate or methacrylic acid monomers mixed with N, N'-methylene-bisacrylamide (BIS), dispersed in an aqueous gelatin matrix were evaluated. Radiation-induced polymerization of the co-monomers generates a fast-relaxing insoluble polymer. Saturation of the polymer using off-resonance Gaussian RF pulses prior to a spin-echo read-out with a short echo time leads to contrast that is dependent on the absorbed dose. This contrast is attributed to magnetization transfer (MT) between free water and the polymer, and direct saturation of water was found to be negligible under the prevailing experimental conditions. The usefulness of MT imaging was assessed by computing the dose resolution obtained with this technique. We found a low value of dose resolution over a wide range of doses could be obtained with a single experiment. This is an advantage over multiple spin echo (MSE) experiments using a single echo spacing where an optimal dose resolution is achieved over only very limited ranges of doses. The results suggest MT imaging protocols may be developed into a useful tool for polymer gel dosimetry. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/334279
- author
- Lepage, M ; McMahon, K ; Galloway, GJ ; De Deene, Y ; Bäck, Sven LU and Baldock, C
- organization
- publishing date
- 2002
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physics in Medicine and Biology
- volume
- 47
- issue
- 11
- pages
- 1881 - 1890
- publisher
- IOP Publishing
- external identifiers
-
- wos:000176454300004
- pmid:12108773
- scopus:0037035839
- ISSN
- 1361-6560
- language
- English
- LU publication?
- yes
- id
- 9fb00bf3-6172-4dfa-922e-9582c897bc41 (old id 334279)
- date added to LUP
- 2016-04-01 12:18:36
- date last changed
- 2022-01-27 01:50:41
@article{9fb00bf3-6172-4dfa-922e-9582c897bc41,
abstract = {{Off-resonance RF pre-saturation was used to obtain contrast in MRI images of polymer gel dosimeters irradiated to doses up to 50 Gy. Two different polymer gel dosimeters composed of 2-hydroxyethyl-acryl ate or methacrylic acid monomers mixed with N, N'-methylene-bisacrylamide (BIS), dispersed in an aqueous gelatin matrix were evaluated. Radiation-induced polymerization of the co-monomers generates a fast-relaxing insoluble polymer. Saturation of the polymer using off-resonance Gaussian RF pulses prior to a spin-echo read-out with a short echo time leads to contrast that is dependent on the absorbed dose. This contrast is attributed to magnetization transfer (MT) between free water and the polymer, and direct saturation of water was found to be negligible under the prevailing experimental conditions. The usefulness of MT imaging was assessed by computing the dose resolution obtained with this technique. We found a low value of dose resolution over a wide range of doses could be obtained with a single experiment. This is an advantage over multiple spin echo (MSE) experiments using a single echo spacing where an optimal dose resolution is achieved over only very limited ranges of doses. The results suggest MT imaging protocols may be developed into a useful tool for polymer gel dosimetry.}},
author = {{Lepage, M and McMahon, K and Galloway, GJ and De Deene, Y and Bäck, Sven and Baldock, C}},
issn = {{1361-6560}},
language = {{eng}},
number = {{11}},
pages = {{1881--1890}},
publisher = {{IOP Publishing}},
series = {{Physics in Medicine and Biology}},
title = {{Magnetization transfer imaging for polymer gel dosimetry}},
volume = {{47}},
year = {{2002}},
}