Magnetic flux density measurement with balanced steady state free precession pulse sequence for MREIT

a simulation study

Atul S. Minhas, Eung Je Woo, Soo Yeol Lee

Research output: Chapter in Book/Report/Conference proceedingConference proceeding contribution

12 Citations (Scopus)

Abstract

Magnetic Resonance Electrical Impedance Tomography (MREIT) utilizes the magnetic flux density Bz, generated due to current injection, to find conductivity distribution inside an object. This Bz can be measured from MR phase images using spin echo pulse sequence. The SNR of Bz and the sensitivity of phase produced by Bz in MR phase image are critical in deciding the resolution of MREIT conductivity images. The conventional spin echo based data acquisition has poor phase sensitivity to current injection. Longer scan time is needed to acquire data with higher SNR. We propose a balanced steady state free precession (b-SSFP) based pulse sequence which is highly sensitive to small off-resonance phase changes. A procedure to reconstruct Bz from MR signal obtained with b-SSFP sequence is described. Phases for b-SSFP signals for two conductivity phantoms of TX 151 and Gelatin are simulated from the mathematical models of b-SSFP signal. It was observed that the phase changes obtained from b-SSFP pulse sequence are highly sensitive to current injection and hence would produce higher magnetic flux density. However, the b-SSFP signal is dependent on magnetic field inhomogeneity and the signal deteriorated highly for small offset from resonance frequency. The simulation results show that the b-SSFP sequence can be utilized for conductivity imaging of a local region where magnetic field inhomogeneity is small. A proper shimming of magnet is recommended before using the b-SSFP sequence.

Original languageEnglish
Title of host publicationProceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Subtitle of host publicationEngineering the Future of Biomedicine, EMBC 2009
Place of PublicationPiscataway
PublisherInstitute of Electrical and Electronics Engineers (IEEE)
Pages2276-2278
Number of pages3
ISBN (Print)9781424432967
DOIs
Publication statusPublished - 2009
Externally publishedYes
Event31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009 - Minneapolis, MN, United States
Duration: 2 Sep 20096 Sep 2009

Conference

Conference31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009
CountryUnited States
CityMinneapolis, MN
Period2/09/096/09/09

Fingerprint Dive into the research topics of 'Magnetic flux density measurement with balanced steady state free precession pulse sequence for MREIT: a simulation study'. Together they form a unique fingerprint.

  • Cite this

    Minhas, A. S., Woo, E. J., & Lee, S. Y. (2009). Magnetic flux density measurement with balanced steady state free precession pulse sequence for MREIT: a simulation study. In Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009 (pp. 2276-2278). Piscataway: Institute of Electrical and Electronics Engineers (IEEE). https://doi.org/10.1109/IEMBS.2009.5335084