Evolution of water diffusion and anisotropy in hyperacute stroke: Significant correlation between fractional anisotropy and T2

Yelda Ozsunar, P. Ellen Grant, Thierry A G M Huisman, Pamela W. Schaefer, Ona Wu, A. Gregory Sorensen, Walter J. Koroshetz, R. Gilberto Gonzalez

Research output: Contribution to journalArticle

Abstract

BACKGROUND AND PURPOSE: We hypothesized that, in acute cerebral ischemic stroke, anisotropic diffusion increases if T2 signal intensity is not substantially elevated and decreases once T2 hyperintensity becomes apparent. Our purpose was to correlate fractional anisotropy (FA) measurements with the clinical time of stroke onset, apparent diffusion coefficients (ADC), and T2 signal intensity. METHODS: Tensor diffusion-weighted images (DWIs) of 25 patients were obtained within 12 hours of symptom onset. Trace DWIs, ADCs, FAs, and echo-planar T2-weighted images (T2WI) were generated. Stroke and contralateral normal volumes of interest (VOIs) were outlined on DWIs and projected onto the inherently coregistered ADC map, FA map, and echo-planar T2WI. Mean signal intensity of the ischemic and contralateral normal VOIs were compared for relatives change in ADC, FA, and signal intensity on T2WIs. RESULTS: A significant negative correlation was observed between FA and T2 signal-intensity change (r = -0.61, P = .00009). A trend of correlation between FA signal intensity and time of onset were found (r = -0.438, P = .025). No significant correlation was found between ADC and FA values (r = -0.302, P = .134). The mean ADC reduction in the ipsilateral ischemic volume was 31% ± 11 compared with the contralateral normal side. CONCLUSION: Change in FA is inversely correlated with T2 signal intensity and, to a lesser extent, the time of onset, but it is not well correlated with ADC values in the acute stage.

Original languageEnglish (US)
Pages (from-to)699-705
Number of pages7
JournalAmerican Journal of Neuroradiology
Volume25
Issue number5
Publication statusPublished - May 2004
Externally publishedYes

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ASJC Scopus subject areas

  • Clinical Neurology
  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

Cite this

Ozsunar, Y., Grant, P. E., Huisman, T. A. G. M., Schaefer, P. W., Wu, O., Sorensen, A. G., ... Gonzalez, R. G. (2004). Evolution of water diffusion and anisotropy in hyperacute stroke: Significant correlation between fractional anisotropy and T2. American Journal of Neuroradiology, 25(5), 699-705.