title: Diffusion-negative stroke: a report of two cases.
abstract: 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.
authors.affiliation: Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: P Y
authors.initials: PY
authors.lastname: Wang
authors.forename: P B
authors.initials: PB
authors.lastname: Barker
authors.forename: R J
authors.initials: RJ
authors.lastname: Wityk
authors.forename: A M
authors.initials: AM
authors.lastname: Uluğ
authors.forename: P C
authors.initials: PC
authors.lastname: van Zijl
authors.forename: N J
authors.initials: NJ
authors.lastname: Beauchamp
mesh_terms: D000208:Acute Disease; D000368:Aged; D002544:Cerebral Infarction / Q000175:diagnosis*; D003937:Diagnosis, Differential; D017352:Echo-Planar Imaging; D005500:Follow-Up Studies; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D008297:Male; D009460:Neurologic Examination; D012680:Sensitivity and Specificity