H-1 MR spectroscopic detection of changes in cerebral metabolites in patients with cerebrovascular disease

Ten patients with severe unilateral stenosis (n = 5), or occlusion (n = 4) of the internal carotid artery or middle and anterior cerebral arteries (n = 1) were examined with H-1 magnetic resonance (MR) spectroscopy and imaging. H-1 MR spectra and spectroscopic imaging of the symptomatic brain regions showed changes in the NAA, Ch, and Cr levels, while lipid signal appeared in the spectra range of 1-2 ppm. In three cases, increased lactic acid was observed. These changes are most likely the result of a pronounced ischemia with marked cell necrosis and gliosis. In all patients, there was a decrease in the NAA/(Ch+Cr) ratio in the symptomatic hemisphere, even when no infarctions were apparent on the MR images. It is therefore suggested that an increase in (Ch+Cr) indicates a metabolic dysfunction due to moderate ischemia