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PT  - JOURNAL ARTICLE
AU  - Moseley, M E
AU  - Kucharczyk, J
AU  - Mintorovitch, J
AU  - Cohen, Y
AU  - Kurhanewicz, J
AU  - Derugin, N
AU  - Asgari, H
AU  - Norman, D
TI  - Diffusion-weighted MR imaging of acute stroke: correlation with T2-weighted and magnetic susceptibility-enhanced MR imaging in cats.
DP  - 1990 May 01
TA  - American Journal of Neuroradiology
PG  - 423--429
VI  - 11
IP  - 3
4099  - http://www.ajnr.org/content/11/3/423.short
4100  - http://www.ajnr.org/content/11/3/423.full
SO  - Am. J. Neuroradiol.1990 May 01; 11
AB  - We evaluated the temporal and anatomic relationships between changes in diffusion-weighted MR image signal intensity, induced by unilateral occlusion of the middle cerebral artery in cats, and tissue perfusion deficits observed in the same animals on T2-weighted MR images after administration of a nonionic intravascular T2 shortening agent. Diffusion-weighted images obtained with strong diffusion-sensitizing gradient strengths (5.6 gauss/cm, corresponding to gradient attenuation factor, b, values of 1413 sec/mm2) displayed increased signal intensity in the ischemic middle cerebral artery territory less than 1 hr after occlusion, whereas T2-weighted images without contrast usually failed to detect injury for 2-3 hr after stroke. After contrast administration (0.5-1.0 mmol/kg by Dy-DTPA-BMA, IV), however, T2-weighted images revealed perfusion deficits (relative hyperintensity) within 1 hr after middle cerebral artery occlusion that corresponded closely to the anatomic regions of ischemic injury shown on diffusion-weighted MR images. Close correlations were also found between early increases in diffusion-weighted MR image signal intensity and disrupted phosphorus-31 and proton metabolite levels evaluated with surface coil MR spectroscopy, as well as with postmortem histopathology. These data indicate that diffusion-weighted MR images more accurately reflect early-onset pathophysiologic changes induced by acute cerebral ischemia than do T2-weighted spin-echo images.