Magnetization transfer using inversion recovery during off-resonance irradiation

Silvia Mangia, Federico De Martino, Timo Liimatainen, Michael Garwood, Shalom Michaeli

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

Estimation of magnetization transfer (MT) parameters in vivo can be compromised by an inability to drive the magnetization to a steady state using allowable levels of radiofrequency (RF) irradiation, due to safety concerns (tissue heating and specific absorption rate (SAR)). Rather than increasing the RF duration or amplitude, here we propose to circumvent the SAR limitation by sampling the formation of the steady state in separate measurements made with the magnetization initially along the -z and +z axis of the laboratory frame, i.e. with or without an on-resonance inversion pulse prior to the off-resonance irradiation. Results from human brain imaging demonstrate that this choice provides a tremendous benefit in the fitting procedure used to estimate MT parameters. The resulting parametric maps are characterized by notably increased tissue specificity as compared to those obtained with the standard MT acquisition in which magnetization is initially along the +z axis only.

Original languageEnglish (US)
Pages (from-to)1346-1350
Number of pages5
JournalMagnetic Resonance Imaging
Volume29
Issue number10
DOIs
StatePublished - Dec 1 2011

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Magnetization
Irradiation
Recovery
Organ Specificity
Neuroimaging
Heating
Safety
Tissue
Brain
Sampling
Imaging techniques

Keywords

  • Brain imaging
  • Exchange
  • Parametric mapping
  • Solid pool

Cite this

Magnetization transfer using inversion recovery during off-resonance irradiation. / Mangia, Silvia; De Martino, Federico; Liimatainen, Timo; Garwood, Michael; Michaeli, Shalom.

In: Magnetic Resonance Imaging, Vol. 29, No. 10, 01.12.2011, p. 1346-1350.

Research output: Contribution to journalArticle

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