Radiology, Vol 195, 65-72, Copyright © 1995 by Radiological Society of North America
Probable Alzheimer disease: diagnosis with proton MR spectroscopy
TK Shonk, RA Moats, P Gifford, T Michaelis, JC Mandigo, J Izumi and BD Ross
Magnetic Resonance Spectroscopy Unit, Huntington Medical Research Institutes, Pasadena, CA 91105.
PURPOSE: To distinguish probable Alzheimer disease (AD) from other
dementias (ODs) and normality in the elderly. MATERIALS AND METHODS: A
double-blind trial of proton magnetic resonance (MR) spectroscopy was
performed, principally in gray matter, in the occipital cortex of 114
patients with dementia (AD [n = 65], OD [n = 39], or frontal lobe dementia
[FLD] [n = 10]), 98 patients without dementia, and 32 healthy control
subjects. RESULTS: Reduced levels of N-acetylaspartate (NAA) (P < .0005)
and increased levels of myo-inositol (MI) (P < .0005) characterize AD.
Patients with OD had significantly reduced levels of NAA (P < .01) but
normal levels of MI (P [vs AD] < .0005). When MI/NAA was used, AD was
distinguished from normality with 83% sensitivity and 98% specificity. When
MI/creatine was used, OD was distinguished from AD and FLD with a negative
predictive rate of 80%, sensitivity of 82%, and specificity of 64%.
CONCLUSION: Hydrogen-1 MR spectroscopy enables identification of mild to
moderate AD with a specificity and sensitivity that suggest clinical
utility.
