Metabolite investigation in both anterior and posterior cingulate gyri in Alzheimer's disease spectrum using 3-tesla MR spectroscopy.

AIMS: In order to evaluate the metabolite changes of both anterior and posterior cingulate gyri during the progression of Alzheimer's disease (AD) pathology, a 3-tesla MR spectroscopy study was performed.

METHODS

Thirty-six patients with AD, 19 patients with amnestic mild cognitive impairment (aMCI), and 23 cognitively normal (CN) subjects were recruited. MR spectroscopy was conducted within the anterior and posterior cingulate gyri. A one-way analysis of co-variance was used to compare the metabolite ratios of each group and correlation analysis was used to show the correlation between the metabolite ratios with the Mini-Mental State Examination (MMSE) and Neuropsychiatric Inventory (NPI).

RESULTS

The N-acetylaspartate/creatine (NAA/Cr) of the posterior cingulate gyrus was significantly higher in CN subjects than in aMCI and AD patients. On the other hand, the myoinositol/creatine (ml/Cr) of the anterior cingulate gyrus was significantly higher in AD patients than in CN subjects and aMCI patients. The ml/Cr of the posterior cingulate gyrus correlated with the MMSE and that of the anterior cingulate gyrus correlated with the NPI.

CONCLUSION

Both the decreased NAA/Cr of the posterior cingulate gyrus and the increased ml/Cr of the anterior cingulate gyrus may reflect biochemical changes in AD according to the posterior-dominant progression of AD pathology.