Medial temporal lobe atrophy on MRI scans and the diagnosis of Alzheimer disease.
BACKGROUND
Despite convenience, accessibility, and strong correlation to severity of Alzheimer disease (AD) pathology, medial temporal lobe atrophy (MTA) has not been used as a criterion in the diagnosis of prodromal and probable AD.


METHODS
Using a newly validated visual rating system, mean MTA scores of three bilateral medial temporal lobe structures were compared for subjects with no cognitive impairment (NCI) (n = 117), nonamnestic mild cognitive impairment (MCI) (n = 46), amnestic MCI (n = 45), and probable AD (n = 53). Correlations between MTA scores and neuropsychological test scores at baseline, and predictors of change in diagnosis at 1-year follow-up were evaluated.


RESULTS
With NCI as the reference group, a mean MTA cut score of 1.33 yielded an optimal sensitivity/specificity of 85%/82% for probable AD subjects and 80%/82% for amnestic MCI subjects. MTA and Clinical Dementia Rating Sum of Boxes scores at baseline were independent and additive predictors of diagnosis at baseline, and of transition from NCI to MCI or from MCI to dementia at 1-year follow-up.


CONCLUSIONS
Medial temporal lobe atrophy (MTA) scores 1) distinguish probable Alzheimer disease (AD) and amnestic mild cognitive impairment (MCI) subjects from nonamnestic MCI and no cognitive impairment (NCI) subjects, 2) help predict diagnosis at baseline, and 3) predict transition from NCI to MCI and from MCI to probable AD. MTA scores should be used as a criterion in the clinical diagnosis of AD.
Duara
R
R
Wien Center for Alzheimer's Disease and Memory Disorders, Mount Sinai Medical Center, 4300 Alton Rd., Miami Beach, FL 33140, USA. ranjan-duara@msmc.com
Loewenstein
D A
DA
Potter
E
E
Appel
J
J
Greig
M T
MT
Urs
R
R
Shen
Q
Q
Raj
A
A
Small
B
B
Barker
W
W
Schofield
E
E
Wu
Y
Y
Potter
H
H
D000368:Aged; D000544:Alzheimer Disease / Q000473:pathology* / Q000503:physiopathology / Q000523:psychology; D001284:Atrophy / Q000209:etiology / Q000473:pathology*; D001931:Brain Mapping; D003072:Cognition Disorders / Q000473:pathology* / Q000503:physiopathology / Q000523:psychology; D003937:Diagnosis, Differential; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006624:Hippocampus / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020534:Parahippocampal Gyrus / Q000473:pathology / Q000503:physiopathology; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D013702:Temporal Lobe / Q000473:pathology* / Q000503:physiopathology