Proton spectroscopy of human stroke: assessment of transverse relaxation times and partial volume effects in single volume steam MRS

Magn Reson Imaging. 1994;12(8):1227-35. doi: 10.1016/0730-725x(94)90087-8.

Abstract

Proton T2 relaxation times were measured in 13 stroke patients and 13 aged-matched normal subjects at 2.1 T. Spectra were acquired from an 8-cc volume using the STEAM sequence with echo times (TE) of 30.4 ms and 270.0 ms and repetition time of 2.8 s. Transverse relaxation times were estimated using two-point calculations. Percentage volume of infarct in the STEAM voxel was measured on spin-echo MRI encompassing the infarct and correlated with the peak amplitude of N-acetylated compounds (NA). T2 values of NA, creatine, and choline resonances showed no significant difference between patients and controls. T2 for lactate in patients was 780 +/- 257 ms, respectively (mean +/- SE, n = 7). In stroke patients, high inverse correlation was found between the absolute NA signal and partial volume of normal brain contributing to each spectrum (p < .001, r = 0.97). Together with unchanged T2, this suggests that NAA largely disappears from infarcted tissue within 24 hr postinfarct.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aspartic Acid / analogs & derivatives
  • Aspartic Acid / analysis
  • Brain Chemistry
  • Cerebrovascular Disorders / diagnosis*
  • Cerebrovascular Disorders / metabolism
  • Choline / analysis
  • Creatine / analysis
  • Female
  • Humans
  • Lactates / analysis
  • Lactic Acid
  • Magnetic Resonance Imaging* / methods
  • Male
  • Middle Aged
  • Models, Structural

Substances

  • Lactates
  • Aspartic Acid
  • Lactic Acid
  • N-acetylaspartate
  • Creatine
  • Choline