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Thermal Excitation of Gadolinium-Based Contrast Agents Using Spin Resonance

Theoretical and experimental investigations into the thermal excitation of liquid paramagnetic contrast agents using the spin resonance relaxation mechanism are presented. The electronic spin-lattice relaxation time τ(1e) of gadolinium-based contrast agents, which is estimated at 0.1 ns, is ten orde...

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Detalles Bibliográficos
Autores principales: Dinger, Steven C., Fridjhon, Peter, Rubin, David M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4920350/
https://www.ncbi.nlm.nih.gov/pubmed/27341338
http://dx.doi.org/10.1371/journal.pone.0158194
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author Dinger, Steven C.
Fridjhon, Peter
Rubin, David M.
author_facet Dinger, Steven C.
Fridjhon, Peter
Rubin, David M.
author_sort Dinger, Steven C.
collection PubMed
description Theoretical and experimental investigations into the thermal excitation of liquid paramagnetic contrast agents using the spin resonance relaxation mechanism are presented. The electronic spin-lattice relaxation time τ(1e) of gadolinium-based contrast agents, which is estimated at 0.1 ns, is ten orders of magnitude faster than the relaxation time of protons in water. The shorter relaxation time is found to significantly increase the rate of thermal energy deposition. To the authors’ knowledge this is the first study of gadolinium based contrast agents in a liquid state used as thermal agents. Analysis shows that when τ(1e) and other experimental parameters are optimally selected, a maximum theoretical heating rate of 29.4 °C.s(−1) could be achieved which would suffice for clinical thermal ablation of neoplasms. The experimental results show a statistically significant thermal response for two out of the four contrast agents tested. The results are compared to the simulated estimates via analysis of a detailed model of the system. While these experimentally determined temperature rises are small and thus of no clinical utility, their presence supports the theoretical analysis and strongly suggests that the chemical structure of the selected compounds plays an important role in this mechanism of heat deposition. There exists an opportunity for the development of alternative gadolinium-based compounds with an order of magnitude longer τ(1e) in a diluted form to be used as an efficient hyperthermia agent for clinical use.
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spelling pubmed-49203502016-07-18 Thermal Excitation of Gadolinium-Based Contrast Agents Using Spin Resonance Dinger, Steven C. Fridjhon, Peter Rubin, David M. PLoS One Research Article Theoretical and experimental investigations into the thermal excitation of liquid paramagnetic contrast agents using the spin resonance relaxation mechanism are presented. The electronic spin-lattice relaxation time τ(1e) of gadolinium-based contrast agents, which is estimated at 0.1 ns, is ten orders of magnitude faster than the relaxation time of protons in water. The shorter relaxation time is found to significantly increase the rate of thermal energy deposition. To the authors’ knowledge this is the first study of gadolinium based contrast agents in a liquid state used as thermal agents. Analysis shows that when τ(1e) and other experimental parameters are optimally selected, a maximum theoretical heating rate of 29.4 °C.s(−1) could be achieved which would suffice for clinical thermal ablation of neoplasms. The experimental results show a statistically significant thermal response for two out of the four contrast agents tested. The results are compared to the simulated estimates via analysis of a detailed model of the system. While these experimentally determined temperature rises are small and thus of no clinical utility, their presence supports the theoretical analysis and strongly suggests that the chemical structure of the selected compounds plays an important role in this mechanism of heat deposition. There exists an opportunity for the development of alternative gadolinium-based compounds with an order of magnitude longer τ(1e) in a diluted form to be used as an efficient hyperthermia agent for clinical use. Public Library of Science 2016-06-24 /pmc/articles/PMC4920350/ /pubmed/27341338 http://dx.doi.org/10.1371/journal.pone.0158194 Text en © 2016 Dinger et al http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
spellingShingle Research Article
Dinger, Steven C.
Fridjhon, Peter
Rubin, David M.
Thermal Excitation of Gadolinium-Based Contrast Agents Using Spin Resonance
title Thermal Excitation of Gadolinium-Based Contrast Agents Using Spin Resonance
title_full Thermal Excitation of Gadolinium-Based Contrast Agents Using Spin Resonance
title_fullStr Thermal Excitation of Gadolinium-Based Contrast Agents Using Spin Resonance
title_full_unstemmed Thermal Excitation of Gadolinium-Based Contrast Agents Using Spin Resonance
title_short Thermal Excitation of Gadolinium-Based Contrast Agents Using Spin Resonance
title_sort thermal excitation of gadolinium-based contrast agents using spin resonance
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4920350/
https://www.ncbi.nlm.nih.gov/pubmed/27341338
http://dx.doi.org/10.1371/journal.pone.0158194
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