We describe MR spectroscopy in 2 patients with frontal sinus mucoceles that showed a dominant metabolite peak at 2.0-ppm chemical shift, simulating N-acetylaspartate (NAA) of normal neuronal tissue. In vitro analysis of postsurgical mucocele samples confirmed that the signal at 2.0 ppm was arising from the methyl moiety of an N-acetyl compound. This is probably caused by N-acetylgalactosamine o...

N-acetylaspartate (NAA) is an amino acid derivative primarily located in the neurons of the adult brain. The function of NAA is incompletely understood. Decrease in brain tissue NAA is presently considered symptomatic and a potential biomarker of acute and chronic neuropathological conditions. The aim of this study was to use microdialysis to investigate the behavior of extracellular NAA (eNAA)...

Two children with acquired immunodeficiency syndrome (AIDS) and progressive encephalopathy underwent MR spectroscopy before and after antiretroviral therapy. Initial MR spectroscopy of the basal ganglia region showed decreased N-acetylaspartate (NAA)/creatine (Cr) and a lactate peak. After therapy, there was improvement in NAA/Cr and an absence of the abnormal lactate peak. We suggest that decr...

In this proton magnetic resonance spectroscopy ((1)H-MRS) study, the authors correlated cognitive improvement after 3 months of treatment with donepezil with changes of N-acetylaspartate (NAA) level and NAA/Creatine (Cr) ratio in the medial temporal and parietal lobe of 17 patients with Alzheimer disease. Treatment response was associated with an increase of NAA and NAA/Cr in the parietal lobe....

We present a case of infantile-onset Alexander disease (AD) with a novel glial fibrillary acidic protein mutation but without clinical evidence of neurologic deterioration. Brain MRI studies showed typical AD findings and increasing size of frontal cavitations. Serial proton MR spectroscopy demonstrated high levels of myo-inositol and lactic acid and decreasing levels of N-acetylaspartate. The ...

We report the findings from whole-brain proton MR spectroscopy, quantifying the neuronal marker N-acetylaspartate (NAA), for 2 presurgical meningioma patients and 10 healthy controls. The patients' whole-brain NAA (WBNAA) concentrations were considerably elevated (3+ SDs) compared with healthy controls when excluding the tumors from brain volume; WBNAA levels normalized following correction to ...

Two patients with acute thiamine deficiency were examined with thalamic single-voxel proton MR spectroscopy. T2-weighted images exhibited increased signal intensity. N-acetylaspartate (NAA)/creatine (Cr) ratios were low without detectable lactate. Owing to substantially decreased choline (Cho) T2, the Cho/Cr ratio was not decreased. After thiamine therapy, the NAA/Cr ratio increased, parallelin...

We herein describe two cases of patients with epilepsy with occipital lobe cortical dysplasia who were studied with both MR spectroscopy and MR diffusion imaging in addition to conventional MR imaging. Greater diffusion abnormalities, as well as more marked decreases in N-acetylaspartate, were observed to occur in the patient harboring a low grade neoplasm within an area of cortical dysplasia t...