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Numerically efficient estimation of relaxation effects in magnetic particle imaging

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Published/Copyright: October 12, 2013
Biomedizinische Technik/Biomedical Engineering
From the journal Biomedizinische Technik/Biomedical Engineering Volume 58 Issue 6

Abstract

Current simulations of the signal in magnetic particle imaging (MPI) are either based on the Langevin function or on directly measuring the system function. The former completely ignores the influence of finite relaxation times of magnetic particles, and the latter requires time-consuming reference scans with an existing MPI scanner. Therefore, the resulting system function only applies for a given tracer type and the properties of the applied scanning trajectory. It requires separate reference scans for different trajectories and does not allow simulating theoretical magnetic particle suspensions. The most accessible and accurate way for including relaxation effects in the signal simulation would be using the Langevin equation. However, this is a very time-consuming approach because it calculates the stochastic dynamics of the individual particles and averages over large particle ensembles. In the current article, a numerically efficient way for approximating the averaged Langevin equation is proposed, which is much faster than the approach based on the Langevin equation because it is directly calculating the averaged time evolution of the magnetization. The proposed simulation yields promising results. Except for the case of small orthogonal offset fields, a high agreement with the full but significantly slower simulation could be shown.

Keywords: approximation; Fokker-Planck; Langevin; magnetic nanoparticles; numerical simulation
Corresponding author: Martin A. Rückert, Experimental Physics 5, University of Würzburg, Am Hubland, 97074 Würzburg, Germany, Phone: +49 931 31 84839, Fax: +49 931 31 85851, E-mail:

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Received: 2013-2-5
Accepted: 2013-9-16
Published Online: 2013-10-12
Published in Print: 2013-12-01

©2013 by Walter de Gruyter Berlin Boston

Articles in the same Issue

  1. Masthead
  2. Masthead
  3. Editorial
  4. Magnetic Particle Imaging – from particle science to imaging technology
  6. Tailoring the magnetic and pharmacokinetic properties of iron oxide magnetic particle imaging tracers
  7. Synthetic routes to magnetic nanoparticles for MPI
  8. Red blood cells as carriers in magnetic particle imaging
  9. Comparison of commercial iron oxide-based MRI contrast agents with synthesized high-performance MPI tracers
  10. Characterization of magnetic nanoparticle systems with respect to their magnetic particle imaging performance
  11. Magnetic spectroscopy of nanoparticle Brownian motion measurement of microenvironment matrix rigidity
  12. Perspectives on clinical magnetic particle imaging
  13. Magnetic particle imaging scanner with 10-kHz drive-field frequency
  14. Twenty-fold acceleration of 3D projection reconstruction MPI
  15. Improved field free line magnetic particle imaging using saddle coils
  16. On the formulation of the image reconstruction problem in magnetic particle imaging
  17. Numerically efficient estimation of relaxation effects in magnetic particle imaging
  18. Simulation of the magnetization dynamics of diluted ferrofluids in medical applications
  19. Safety considerations for magnetic fields of 10 mT to 100 mT amplitude in the frequency range of 10 kHz to 100 kHz for magnetic particle imaging
https://doi.org/10.1515/bmt-2013-0015
Keywords for this article
approximation; Fokker-Planck; Langevin; magnetic nanoparticles; numerical simulation

Articles in the same Issue

  1. Masthead
  2. Masthead
  3. Editorial
  4. Magnetic Particle Imaging – from particle science to imaging technology
  6. Tailoring the magnetic and pharmacokinetic properties of iron oxide magnetic particle imaging tracers
  7. Synthetic routes to magnetic nanoparticles for MPI
  8. Red blood cells as carriers in magnetic particle imaging
  9. Comparison of commercial iron oxide-based MRI contrast agents with synthesized high-performance MPI tracers
  10. Characterization of magnetic nanoparticle systems with respect to their magnetic particle imaging performance
  11. Magnetic spectroscopy of nanoparticle Brownian motion measurement of microenvironment matrix rigidity
  12. Perspectives on clinical magnetic particle imaging
  13. Magnetic particle imaging scanner with 10-kHz drive-field frequency
  14. Twenty-fold acceleration of 3D projection reconstruction MPI
  15. Improved field free line magnetic particle imaging using saddle coils
  16. On the formulation of the image reconstruction problem in magnetic particle imaging
  17. Numerically efficient estimation of relaxation effects in magnetic particle imaging
  18. Simulation of the magnetization dynamics of diluted ferrofluids in medical applications
  19. Safety considerations for magnetic fields of 10 mT to 100 mT amplitude in the frequency range of 10 kHz to 100 kHz for magnetic particle imaging
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