Fast and high-resolution quantitative mapping of tissue water content with full brain coverage for clinically-driven studies

Mohammad Sabati, Andrew A Maudsley

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

An efficient method for obtaining longitudinal relaxation time (T1) maps is based on acquiring two spoiled gradient recalled echo (SPGR) images in steady states with different flip angles, which has also been extended, with additional acquisitions, to obtain a tissue water content (M0) map. Several factors, including inhomogeneities of the radio-frequency (RF) fields and low signal-to-noise ratios may negatively affect the accuracy of this method and produce systematic errors in T1 and M0 estimations. Thus far, these limitations have been addressed by using additional measurements and applying suitable corrections; however, the concomitant increase in scan time is undesirable for clinical studies. In this note, a modified dual-acquisition SPGR method based on an optimization of the sequence formulism is presented for good and reliable M0 mapping with an isotropic spatial resolution of 1×1×1mm3 that covers the entire human brain in 6:30min. A combined RF transmit/receive map is estimated from one of the SPGR scans and the optimal flip angles for M0 map are found analytically. The method was successfully evaluated in eight healthy subjects producing mean M0 values of 69.8% (in white matter) and 80.1% (in gray matter) that are in good agreement with those found in the literature and with high reproducibility. The mean value of the resultant voxel-based coefficients-of-variation was 3.6%.

Original languageEnglish
Pages (from-to)1752-1759
Number of pages8
JournalMagnetic Resonance Imaging
Volume31
Issue number10
DOIs
StatePublished - Dec 1 2013

Fingerprint

Water content
Brain
Tissue
Water
Radio
Systematic errors
Signal-To-Noise Ratio
Relaxation time
Signal to noise ratio
Healthy Volunteers

Keywords

  • Dual-angle acquisition
  • Quantitative MRI
  • Reproducibility
  • RF nonuniformity
  • SPGR sequence
  • T1 mapping
  • Water content mapping

ASJC Scopus subject areas

  • Biophysics
  • Radiology Nuclear Medicine and imaging
  • Biomedical Engineering

Cite this

Fast and high-resolution quantitative mapping of tissue water content with full brain coverage for clinically-driven studies. / Sabati, Mohammad; Maudsley, Andrew A.

In: Magnetic Resonance Imaging, Vol. 31, No. 10, 01.12.2013, p. 1752-1759.

Research output: Contribution to journalArticle

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