BACKGROUND AND PURPOSE: Proton spectroscopy and quantitative diffusion-weighted imaging (DWI) were used to investigate the pertinence of N-acetyl aspartate (NAA) as a reliable marker of neuronal density in human stroke. METHODS: The time courses of tissue water apparent diffusion coefficient (ADC(w)) and metabolite T2 were investigated on a plane corresponding to the largest area of cerebral infarction, within and outside the site of infarction in 71 patients with a large cortical middle cerebral artery territory infarction. RESULTS: Significant reductions are seen in NAA T2 deep within the infarction during the period comprised between 5 and 20 days postinfarction; the relaxation times appearing to normalise several months after stroke. After an acute reduction in ADC(w), the pseudonormalisation of ADC(w) occurs at 8-12 days after the ischaemic insult. The minimum in N-acetyl aspartate T2 relaxation times and the pseudonormalisation of ADC(w) appear to coincide. CONCLUSIONS: The data suggest that modifications in the behaviour of the observed proton metabolites occur during the period when the vasogenic oedema is formed and cell membrane integrity is lost. For this reason, NAA may not be a reliable marker of neuronal density during this period.
BACKGROUND AND PURPOSE: Proton spectroscopy and quantitative diffusion-weighted imaging (DWI) were used to investigate the pertinence of N-acetyl aspartate (NAA) as a reliable marker of neuronal density in humanstroke. METHODS: The time courses of tissue water apparent diffusion coefficient (ADC(w)) and metabolite T2 were investigated on a plane corresponding to the largest area of cerebral infarction, within and outside the site of infarction in 71 patients with a large cortical middle cerebral artery territory infarction. RESULTS: Significant reductions are seen in NAA T2 deep within the infarction during the period comprised between 5 and 20 days postinfarction; the relaxation times appearing to normalise several months after stroke. After an acute reduction in ADC(w), the pseudonormalisation of ADC(w) occurs at 8-12 days after the ischaemic insult. The minimum in N-acetyl aspartate T2 relaxation times and the pseudonormalisation of ADC(w) appear to coincide. CONCLUSIONS: The data suggest that modifications in the behaviour of the observed proton metabolites occur during the period when the vasogenic oedema is formed and cell membrane integrity is lost. For this reason, NAA may not be a reliable marker of neuronal density during this period.
Authors: John R Moffett; Brian Ross; Peethambaran Arun; Chikkathur N Madhavarao; Aryan M A Namboodiri Journal: Prog Neurobiol Date: 2007-01-05 Impact factor: 11.685
Authors: A L Coon; F Arias-Mendoza; G P Colby; J Cruz-Lobo; J Mocco; W J Mack; R J Komotar; T R Brown; E S Connolly Journal: AJNR Am J Neuroradiol Date: 2006-05 Impact factor: 3.825
Authors: Nawaf Yassi; Bruce C V Campbell; Bradford A Moffat; Christopher Steward; Leonid Churilov; Mark W Parsons; Geoffrey A Donnan; Patricia M Desmond; Stephen M Davis; Andrew Bivard Journal: Neuroradiology Date: 2015-09-16 Impact factor: 2.804
Authors: Fernando A Bozza; Philippe Garteiser; Marcus F Oliveira; Sabrina Doblas; Rebecca Cranford; Debra Saunders; Inna Jones; Rheal A Towner; Hugo C Castro-Faria-Neto Journal: J Cereb Blood Flow Metab Date: 2009-10-21 Impact factor: 6.200