Frontal paralimbic network atrophy in very mild behavioral variant frontotemporal dementia.
BACKGROUND
Behavioral variant frontotemporal dementia (bvFTD) strikes hardest at the frontal lobes, but the sites of earliest injury remain unclear.


OBJECTIVE
To determine atrophy patterns in distinct clinical stages of bvFTD, testing the hypothesis that the mildest stage is restricted to frontal paralimbic cortex.


METHODS
A bvFTD cohort study.


METHODS
University hospital dementia clinic.


METHODS
Patients with bvFTD with Clinical Dementia Rating (CDR) scale scores of 0.5 (n = 15), 1 (n = 15), or 2 to 3 (n = 15) age and sex matched to each other and to 45 healthy controls.


METHODS
Magnetic resonance voxel-based morphometry estimated gray matter and white matter atrophy at each disease stage compared with controls.


RESULTS
Patients with a CDR score of 0.5 had gray matter loss in frontal paralimbic cortices, but atrophy also involved a network of anterior cortical and subcortical regions. A CDR score of 1 showed more extensive frontal gray matter atrophy and white matter losses in corpus callosum and brainstem. A CDR score of 2 to 3 showed additional posterior insula, hippocampus, and parietal involvement, with white matter atrophy in presumed frontal projection fibers.


CONCLUSIONS
Very mild bvFTD targets a specific subset of frontal and insular regions. More advanced disease affects white matter and posterior gray matter structures densely interconnected with the sites of earliest injury.
Seeley
William W
WW
UCSF Memory and Aging Center, University of California-San Francisco, 350 Parnassus Avenue, San Francisco, CA 94143-1207, USA. wseeley@memory.ucsf.edu
Crawford
Richard
R
Rascovsky
Katya
K
Kramer
Joel H
JH
Weiner
Michael
M
Miller
Bruce L
BL
Gorno-Tempini
Maria Luisa
ML
D000368:Aged; D001284:Atrophy / Q000175:diagnosis; D001933:Brain Stem / Q000473:pathology; D016022:Case-Control Studies; D015331:Cohort Studies; D003337:Corpus Callosum / Q000473:pathology; D003704:Dementia / Q000473:pathology*; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008032:Limbic System / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D012920:Social Behavior Disorders / Q000209:etiology / Q000473:pathology*