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PT  - JOURNAL ARTICLE
AU  - Wang, Paul Y-K.
AU  - Barker, Peter B.
AU  - Wityk, Robert J.
AU  - Uluğ, Aziz M.
AU  - van Zijl, Peter C. M.
AU  - Beauchamp, Norman J.
TI  - Diffusion-Negative Stroke: A Report of Two Cases
DP  - 1999 Nov 01
TA  - American Journal of Neuroradiology
PG  - 1876--1880
VI  - 20
IP  - 10
4099  - http://www.ajnr.org/content/20/10/1876.short
4100  - http://www.ajnr.org/content/20/10/1876.full
SO  - Am. J. Neuroradiol.1999 Nov 01; 20
AB  - Summary: Diffusion-weighted MR imaging is generally thought to be highly sensitive for the diagnosis of acute stroke. We report two cases of hyperacute stroke with absence of changes on diffusion-weighted images within 4 hours of symptom onset. Follow-up studies, performed 4 days later, showed infarction in regions compatible with the clinical presentation and (in one case) with the initial perfusion deficit. These cases indicate that normal findings on diffusion-weighted images in patients with suspected cerebral ischemia do not rule out impending infarction.