Relaxation in x-space Magnetic Particle Imaging

  • Laura R. Croft
  • Patrick Goodwill
  • Matt Ferguson
  • Kannan Krishnan
  • Steven Conolly
Part of the Springer Proceedings in Physics book series (SPPHY, volume 140)

Abstract

Magnetic particle imaging (MPI) is an emerging medical imaging modality capable of high-sensitivity images with unprecedented contrast and without ionizing radiation [1]. Our laboratory previously developed the x-space theory for MPI, which describes MPI as a scanning process in the spatial domain [2,3]. X-space MPI is particularly critical as it permits real-time image reconstruction, orders of magnitude faster than the traditional harmonic space system matrix reconstruction methods. The x-space theory was derived assuming adiabatic and instantaneous alignment of ultra-small superparamagnetic iron oxide nanoparticles (USPIOs) with the applied magnetic field. However, in reality the magnetization lags behind the applied field due to relaxation. Here, we include relaxation in the x-space MPI theory and show that real-time reconstruction is still feasible even with relaxation effects.

Keywords

Chronic Kidney Disease Point Spread Function Relaxation Effect Scanning Direction Relaxation Time Constant 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag GmbH Berlin Heidelberg 2012

Authors and Affiliations

  • Laura R. Croft
    • 1
  • Patrick Goodwill
    • 1
  • Matt Ferguson
    • 3
  • Kannan Krishnan
    • 3
  • Steven Conolly
    • 1
    • 2
  1. 1.Departments of BioengineeringUniversity of California, BerkeleyBerkeleyUSA
  2. 2.EECSUniversity of California, BerkeleyBerkeleyUSA
  3. 3.Department of Materials Science & EngineeringUniversity of WashingtonSeattleUSA

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