Proton Magnetic Resonance Spectroscopy in Mild Cognitive Impairment and Alzheimer’s Disease: A Preliminary Study
Wiboon Suriyajakryuththana MD*, Lojana Tuntiyatorn MD*, Nuttika Teepprasarn MD*, Chakrit Sukying MD**
Affiliation : * Department of Diagnostic and Therapeutic Radiology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand ** Department of Psychiatry, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
Background : Mild cognitive impairment (MCI) is recognized as a transitional clinical state between normal aging and
Alzheimer’s disease (AD) and has significant higher rate of progression to AD.
Objective : To compare the changes of metabolites between AD and MCI in specific locations of the brain by using Magnetic
Resonance Spectroscopy (MRS).
Material and Method: MMSE-Thai 2002 and neuropsychological test were performed in 17 patients with memory problem,
classified into AD and MCI (10, 7 patients respectively). All patients and three age-matched cognitively normal volunteers
were examined with conventional MRI and MRS of the brain. Volumes of interest were located at both-sided frontal and parietal
deep white matter. NAA/Cr, Cho/Cr, and mI/Cr ratios of the patients were analyzed and statistically evaluated relative to
cognitively normal volunteers. Statistical analysis was performed using Cohen’s kappa coefficient and Kruskal-Wallis test.
Results : There was no statistically significant change in metabolites in all brain regions. For AD relative to cognitively
normal volunteers, there were strong tendency toward statistically significant decreased NAA/Cr at the left frontal and left
parietal regions (p = 0.043 each) and decreased Cho/Cr at the left frontal region (p = 0.028).
Conclusion : The changes of the metabolite ratios of MCI were much closer to AD. Strong tendency toward statistically
significant decreased NAA/Cr in the left cerebral hemisphere, predominantly parietal region and strong tendency toward
statistically significant decreased Cho/Cr at the left frontal region were indicative of neurodegeneration and replacement
by gliosis. MRS may be useful for predict a chance that cognitively normal people may convert to the AD.
Keywords : Magnetic resonance spectroscopy, Mild cognitive impairment, Alzheimer’s disease
