Table 2. Summary of 1H-MRS Findings in Alzheimer's Disease
MR Protocol
/Salient Findings
Miller et al (1993) / 1.5T STEAM Te = 30 / Parietal Cortex:1. NAA/Cr ¯ 5% in AD
2. MI/Cr 11% in AD
Occipital Cortex:
1. NAA/Cr ¯ 11% in AD
2. MI/Cr 22% in AD
Moats et al (1994) / 1.5T STEAM
Various Te / 1. NAA ¯ 11% in AD
2. MI 50% in AD
3. No Cho changes in AD
Meyerhoff et al (1994) / 2T CSI PRESS Te = 272 / 1. NAA/Cr ¯ 12% in WM only
2. Chol/Cr 23% GM only
Follow up in posterior parietal area showed:
1. 30% Chol/Cr in mesial GM
2. 27% Chol/Cr in lateral WM
Mohankrishnan et al (1995) / Post-mortem in vitro / 1. NAA depletion correlated with AD pathology
Shonk et al (1995) / 1.5T STEAM Te = 30 / 1. AD, FTD, OD 10%¯ in NAA/Cr
2. AD & FTD 15% in MI/Cr
3. No Cho/Cr differences
4. MRS discrimination of AD from:
§ Controls: Positive Predictive Value: 98%
§ Other Dementias: Positive Predictive Value: 74%; Negative Predictive Value: 80%
Parnetti et al (1996) / 1.5T STEAM Te = 20 / 1. AD and AAMI NAA ¯ 12%
2. AD MI 22%; AAMI ns increase.
3. No group Cho or Cr differences.
Parnetti et al (1997) / 1.5T STEAM
Te = 35 / 1. AD ¯ NAA in GM (15%) and WM (8%)
2. AD MI 18% in grey matter only.
3. NAA/MI 100% discrimination of AD
4. Frontal WM MI & AD duration r= 0.70
Heun et al (1997) / 1.5T PRESS Te = 136 / 1. AD 16% ¯ in NAA in WM
2. No MI differences.
3. NAA/Cho associated with Blessed Dementia rating (r=-0.69) and MMSE (r=0.82)
Satlin et al (1997) / 1.5T STEAM
Te = 272 / 1. Six-month placebo control trial of xanomeline
2. Repeat spectra found Cho/Cr decrease of about 20% compared to baseline in medication subjects only.
Doraiswamy et al (1998) / 1.5T CSI / 1. Baseline MI/NAA strongly negatively correlated to MMSE score 12 months later (r=-0.70).
Rose et al (1999) / 2T VOSY
Te = 30 / 1. Same day test-retest correlation of metabolite ratios was high.
2. Longitudinal test-retest correlation of metabolite ratios was high for all ratios except Cho/Cr (r=0.50).
3. AD patients has significantly ¯ NAA (15%) and MI (18%).
4. NAA/MI highly correlated with MMSE (r=0.8).
Pfefferbaum et al (1999) / 1.5T CSI / 1. Gray matter NAA ¯ in AD after controlling for brain volume.
2. Gray matter Cho in AD.
3. Higher Cho related to lower face-recognition scores (r= -0.7); higher Cr related to lower word recognition scores (r= -0.67).
Rai et al (1999) / 1.0T STEAM Te = 30 / 1. Lower field strength MR scanners can also replicate abnormal MI/Cr elevation in AD
2. Distribution of MI/Cr showed almost no overlap between AD and MID patients
Kantarci et al (2000) / 1.5T PRESS
Te= 135 & 30 / 1. Three VOI: medial occipital, posterior cingulate (PC) and left superior temporal lobe (STL).
2. AD ¯ NAA in STL and PC compared to MCI or Controls
3. PC MI in MCI and AD compared to controls
PRESS
Te=272 / 1. AD medial temporal lobe (MTL) VOI showed ¯ NAA compared to controls and compared to within-individual primary motor cortex (PMC).2. No Cho changes in medial temporal lobe.
3. NAA change (MTL/PMC) predicted MMSE and ADAScog scores (r=-0.54)
Haley et al (2000) / 1.5T STEAM
Te = 10 / 1. No NAA or Cho changes in hippocampus of AD patients
2. MI in hippocampus 20%
Table 2. Summary of 1H-MRS findings in Alzheimer's disease.
All studies utilized the NINCDS-ADRDA criteria for AD diagnosis. Te = Echo time (msec). Groups: AD= Alzheimer's disease, AAMI= Age Associated Memory Impairment, MCI = Mild Cognitive Impairment, FTD= Fronto-temporal Dementia, MID = Multi Infarct Dementia, OD = Other Dementias, C= Controls, GM= Grey matter, WM= White Matter. ADAScog = Alzheimer Disease Assessment Scale cognitive subscale.