In vivo measurements of multi-component T2 relaxation behaviour in guinea pig brain

Paula J. Gareau, Brian K. Rutt, Chris V. Bowen, Stephen J. Karlik, J. Ross Mitchell

Research output: Contribution to journalArticle

40 Scopus citations

Abstract

Multi-echo Carr-Purcell-Meiboom-Gill (CPMG) imaging sequences were implemented on 1.5 T and 4.0 T imaging systems to test their ability to measure in vivo multi-component T2 relaxation behavior in normal guinea pig brain. The known dependence of accurate T2 measurements on the signal-to- noise ratio (SNR) was explored in vivo by comparing T2 decay data obtained using three methods to increase SNR (improved RF coil design, signal averaging and increased magnetic field strength). Good agreement between T2 values of nickel-doped agarose phantoms was found between imaging and spectroscopic methods. T2 values were determined for gray matter (GM) and white matter (WM) locations from images of guinea pig brain in vivo. T2 measurements of GM were found to be monoexponential at both field strengths. The mean T2 times for GM were 71 ms at 1.5 T, and 53 ms at 4.0T. The highest average SNR was achieved using an improved RF coil at 4.0T. In this case, two peaks were extracted in WM, a 'short' T2 peak at approximately 6 ms, and a 'medium' T2 peak at approximately 48 ms. T2 values in GM and the major component of WM were significantly decreased at 4.0T compared to 1.5 T. The improved SNR attained with this optimized imaging protocol at 4.0T has allowed for the first time extraction of the myelin-sensitive T2 component of WM in animal brain in vivo.

Original languageEnglish (US)
Pages (from-to)1319-1325
Number of pages7
JournalMagnetic Resonance Imaging
Volume17
Issue number9
DOIs
StatePublished - Nov 1 1999

Keywords

  • 'Short' T component
  • Multiexponential relaxation
  • Myelin water
  • Tissue characterization
  • Transverse relaxation

ASJC Scopus subject areas

  • Biophysics
  • Biomedical Engineering
  • Radiology Nuclear Medicine and imaging

Fingerprint Dive into the research topics of 'In vivo measurements of multi-component T<sub>2</sub> relaxation behaviour in guinea pig brain'. Together they form a unique fingerprint.

  • Cite this

    Gareau, P. J., Rutt, B. K., Bowen, C. V., Karlik, S. J., & Mitchell, J. R. (1999). In vivo measurements of multi-component T2 relaxation behaviour in guinea pig brain. Magnetic Resonance Imaging, 17(9), 1319-1325. https://doi.org/10.1016/S0730-725X(99)00064-8