Quantitative evaluation of cerebral metabolites and cerebral blood flow inpatients with carotid stenosis

We examined the metabolic and hemodynamic status of patients with severe ca rotid stenosis and evaluated the effectiveness of carotid endarterectomy (C EA) by comparing pre- and post-operative results of quantitative proton mag netic resonance spectroscopy CH-MRS) and single-photon emission computed to mography (SPECT). Quantitative H-1-MRS and SPECT were performed in 17 patie nts with severe carotid stenosis before CEA; in 10 patients the examination s were repeated after CEA. There was a significant correlation between the degree of internal carotid artery (ICA) stenosis and the N-acetyl-aspartate (NAA) concentration, and between CBF and NAA in the basal ganglia. In 10 o f the 17 patients (58.8%) we noted a decrease of NAA on H-1-MRS, After CEA in these patients, NAA was significantly increased, and in 7 of 8 patients whose pre-operative SPECT had indicated impairment of cerebral vasoreactivi ty, it was improved. Quantitative H-1-MRS and CBF measurements can indicate the severity of metabolic and hemodynamic impairment in patients with seve re carotid stenosis, and can help to assess the effectiveness of CEA.