title: Spectroscopic data following stroke reveal tissue abnormality beyond the region of T2-weighted hyperintensity.
abstract: Cerebral tissue with T2 magnetic resonance imaging (MRI) abnormalities following stroke is generally considered infarcted, while surrounding regions with normal MRI appearance are believed to be healthy. To assess whether these surrounding regions consist of normal tissue, we explored the distribution of N-acetylaspartate (NAA) and lactate within and around the hyperintense area on T2-weighted MRI using proton MR spectroscopy. The study was carried out in 25 patients with middle cerebral artery occlusion imaged between 1 and 42 days after stroke onset. NAA/choline (Cho) ratios were significantly reduced in both areas of T2 hyperintensity and in surrounding tissue. The reduction was greater in the region of T2 hyperintensity than in the surrounding region (-50% vs. -28%, respectively) and was unrelated to the delay after the ictus. Lactate/Cho ratios increased massively within the abnormal T2 area, but did not differ from control values beyond the margin of hyperintensity. Overall data indicate that T2 visible lesions on MRI do not infer the entire injured tissue.
authors.affiliation: Laboratoire de Pharmacodynamie, Faculté de Pharmacie, BP 87 900, 21079 Dijon Cedex, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Demougeot
authors.forename: Paul
authors.initials: P
authors.lastname: Walker
authors.forename: Alain
authors.initials: A
authors.lastname: Beley
authors.forename: Christine
authors.initials: C
authors.lastname: Marie
authors.forename: Olivier
authors.initials: O
authors.lastname: Rouaud
authors.forename: Maurice
authors.initials: M
authors.lastname: Giroud
authors.forename: François
authors.initials: F
authors.lastname: Brunotte
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D002794:Choline / Q000032:analysis / Q000378:metabolism; D003401:Creatine / Q000032:analysis / Q000378:metabolism; D005260:Female; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000175:diagnosis / Q000378:metabolism; D019344:Lactic Acid / Q000032:analysis / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D020521:Stroke / Q000175:diagnosis* / Q000378:metabolism*; D013997:Time Factors
chemical_list: D001224:Aspartic Acid; D019344:Lactic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline