Literature DB >> 22918621

Eddy current compensation for delta relaxation enhanced MR by dynamic reference phase modulation.

Uvo Christoph Hoelscher1, Peter M Jakob.   

Abstract

OBJECT: Eddy current compensation by dynamic reference phase modulation (eDREAM) is a compensation method for eddy current fields induced by B 0 field-cycling which occur in delta relaxation enhanced MR (dreMR) imaging. The presented method is based on a dynamic frequency adjustment and prevents eddy current related artifacts. It is easy to implement and can be completely realized in software for any imaging sequence.
MATERIALS AND METHODS: In this paper, the theory of eDREAM is derived and two applications are demonstrated. The theory describes how to model the behavior of the eddy currents and how to implement the compensation. Phantom and in vivo measurements are carried out and demonstrate the benefits of eDREAM.
RESULTS: A comparison of images acquired with and without eDREAM shows a significant improvement in dreMR image quality. Images without eDREAM suffer from severe artifacts and do not allow proper interpretation while images with eDREAM are artifact free. In vivo experiments demonstrate that dreMR imaging without eDREAM is not feasible as artifacts completely change the image contrast.
CONCLUSION: eDREAM is a flexible eddy current compensation for dreMR. It is capable of completely removing the influence of eddy currents such that the dreMR images do not suffer from artifacts.

Mesh:

Year:  2012        PMID: 22918621     DOI: 10.1007/s10334-012-0335-6

Source DB:  PubMed          Journal:  MAGMA        ISSN: 0968-5243            Impact factor:   2.310


  7 in total

1.  The magnetic field dependence of water T1 in tissues.

Authors:  Galina Diakova; Jean-Pierre Korb; Robert G Bryant
Journal:  Magn Reson Med       Date:  2011-12-05       Impact factor: 4.668

2.  Single point measurements of magnetic field gradient waveform.

Authors:  David J Goodyear; Maurice Shea; Steven D Beyea; Nadim J Shah; Bruce J Balcom
Journal:  J Magn Reson       Date:  2003-07       Impact factor: 2.229

3.  Quantification and localization of contrast agents using delta relaxation enhanced magnetic resonance at 1.5 T.

Authors:  Uvo Christoph Hoelscher; Steffen Lother; Florian Fidler; Martin Blaimer; Peter Jakob
Journal:  MAGMA       Date:  2011-11-27       Impact factor: 2.310

4.  Delta relaxation enhanced MR: improving activation-specificity of molecular probes through R1 dispersion imaging.

Authors:  Jamu K Alford; Brian K Rutt; Timothy J Scholl; William B Handler; Blaine A Chronik
Journal:  Magn Reson Med       Date:  2009-04       Impact factor: 4.668

5.  A programmable pre-emphasis system.

Authors:  H M Gach; I J Lowe; D P Madio; A Caprihan; S A Altobelli; D O Kuethe; E Fukushima
Journal:  Magn Reson Med       Date:  1998-09       Impact factor: 4.668

6.  A programmable eddy-current compensation system for MRI and localized spectroscopy.

Authors:  M E Fry; S Pittard; I R Summers; W Vennart; F T Goldie
Journal:  J Magn Reson Imaging       Date:  1997 Mar-Apr       Impact factor: 4.813

7.  A review of normal tissue hydrogen NMR relaxation times and relaxation mechanisms from 1-100 MHz: dependence on tissue type, NMR frequency, temperature, species, excision, and age.

Authors:  P A Bottomley; T H Foster; R E Argersinger; L M Pfeifer
Journal:  Med Phys       Date:  1984 Jul-Aug       Impact factor: 4.071

  7 in total

北京卡尤迪生物科技股份有限公司 © 2022-2023.