Acute Stroke

This 45 year-old woman noticed the sudden onset of right body weakness and trouble speaking at about 400 PM. At the hospital, Roentgen-ray CT was normal, and the conventional T2-weighted MR image acquired 8 hours after onset of symptoms showed only subtle changes, appreciated only in retrospect. Please see Tour 1.
Some details have been altered to protect confidentiality.
Keith A. Johnson (keith@bwh.harvard.edu), J. Alex Becker (jabecker@mit.edu)