title: Proton MR spectroscopy in acute middle cerebral artery stroke.
abstract: OBJECTIVE
  To investigate the feasibility of performing multisection proton MR spectroscopy in patients with acute stroke, and to determine whether this imaging technique can depict ischemic or infarcted brain regions.
  
  
  METHODS
  Multisection proton MR spectroscopy, MR imaging, and MR angiography were performed within 24 hours of stroke onset (mean, 12 hours) in 12 patients who had had a stroke of the middle cerebral artery. Spectra were analyzed from brain regions containing T2 hyperintensity abnormalities on MR images, from regions immediately adjacent to these abnormalities, and from anatomically similar contralateral regions. Areas of brain containing lactate were compared with areas of T2 hyperintensities on MR images.
  
  
  RESULTS
  One data set was discarded because of excessive artifacts from patient motion. Regions of T2 hyperintensities on MR images were found to contain elevated lactate (all 11 cases) and reduced N-acetyl-aspartate (10 of 11 cases) relative to contralateral measurements. Lactate levels in regions adjacent to T2 hyperintensities were not significantly different from those of infarcted brain. On the other hand, N-acetyl-aspartate was significantly lower in regions of infarction compared with periinfarct tissue. Areas of brain containing elevated lactate significantly exceeded those of T2 abnormality.
  
  
  CONCLUSIONS
  Proton MR spectroscopy is feasible for imaging patients with acute stroke. In the early stages of stroke, tissue containing elevated lactate but no other spectroscopic or MR imaging abnormality can be identified. Such regions may represent an ischemic zone at risk of infarction.
authors: Department of Radiology, Johns Hopkins Medical Institutions, Baltimore, Md, USA.
authors: J H
authors: JH
authors: Gillard
authors: P B
authors: PB
authors: Barker
authors: P C
authors: PC
authors: van Zijl
authors: R N
authors: RN
authors: Bryan
authors: S M
authors: SM
authors: Oppenheimer
mesh_terms: D000208:Acute Disease; D000368:Aged; D016477:Artifacts; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D002545:Brain Ischemia / Q000175:diagnosis / Q000378:metabolism; D002536:Cerebral Arteries; D002544:Cerebral Infarction / Q000175:diagnosis / Q000378:metabolism; D002561:Cerebrovascular Disorders / Q000175:diagnosis* / Q000378:metabolism; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007773:Lactates / Q000378:metabolism; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D011522:Protons
chemical_list: D007773:Lactates; D011522:Protons; D001224:Aspartic Acid; C000179:N-acetylaspartate