title: White matter tract damage in the behavioral variant of frontotemporal and corticobasal dementia syndromes.
abstract: The phenotypes of the behavioral variant of frontotemporal dementia and the corticobasal syndrome present considerable clinical and anatomical overlap. The respective patterns of white matter damage in these syndromes have not been directly contrasted. Beyond cortical involvement, damage to white matter pathways may critically contribute to both common and specific symptoms in both conditions. Here we assessed patients with the behavioral variant of frontotemporal dementia and corticobasal syndrome with whole-brain diffusion tensor imaging to identify the white matter networks underlying these pathologies. Twenty patients with the behavioral variant of frontotemporal dementia, 19 with corticobasal syndrome, and 15 healthy controls were enrolled in the study. Differences in tract integrity between (i) patients and controls, and (ii) patients with the corticobasal syndrome and the behavioral variant of frontotemporal dementia were assessed with whole brain tract-based spatial statistics and analyses of regions of interest. Behavioral variant of frontotemporal dementia and the corticobasal syndrome shared a pattern of bilaterally decreased white matter integrity in the anterior commissure, genu and body of the corpus callosum, corona radiata and in the long intrahemispheric association pathways. Patients with the behavioral variant of frontotemporal dementia showed greater damage to the uncinate fasciculus, genu of corpus callosum and forceps minor. In contrast, corticobasal syndrome patients had greater damage to the midbody of the corpus callosum and perirolandic corona radiata. Whereas several compact white matter pathways were damaged in both the behavioral variant of frontotemporal dementia and corticobasal syndrome, the distribution and degree of white matter damage differed between them. These findings concur with the distinctive clinical manifestations of these conditions and may improve the in vivo neuroanatomical and diagnostic characterization of these disorders.
authors: D'Or Institute for Research and Education (IDOR), Rio de Janeiro, Brazil; Institute of Biomedical Sciences and National Center of Structural Biology and Bioimaging (CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Fernanda
authors: F
authors: Tovar-Moll
authors: D'Or Institute for Research and Education (IDOR), Rio de Janeiro, Brazil.
authors: Ricardo
authors: R
authors: de Oliveira-Souza
authors: D'Or Institute for Research and Education (IDOR), Rio de Janeiro, Brazil; Institute of Biomedical Sciences and National Center of Structural Biology and Bioimaging (CENABIO), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Ivanei Edson
authors: IE
authors: Bramati
authors: D'Or Institute for Research and Education (IDOR), Rio de Janeiro, Brazil; Institute of Psychiatry at King's College, De Crespigny Park, London, United Kingdom.
authors: Roland
authors: R
authors: Zahn
authors: National Institute of Neurological Disorders and Stroke, National Institute of Health (NIH), Bethesda, Maryland, United States of America.
authors: Alyson
authors: A
authors: Cavanagh
authors: National Institute of Neurological Disorders and Stroke, National Institute of Health (NIH), Bethesda, Maryland, United States of America.
authors: Michael
authors: M
authors: Tierney
authors: D'Or Institute for Research and Education (IDOR), Rio de Janeiro, Brazil.
authors: Jorge
authors: J
authors: Moll
authors: National Institute of Neurological Disorders and Stroke, National Institute of Health (NIH), Bethesda, Maryland, United States of America; Rehabilitation Institute of Chicago, Chicago, Illinois, United States of America.
authors: Jordan
authors: J
authors: Grafman
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000473:pathology / Q000503:physiopathology*; D003704:Dementia / Q000503:physiopathology*; D056324:Diffusion Tensor Imaging / Q000379:methods; D005260:Female; D057180:Frontotemporal Dementia / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013577:Syndrome; D066127:White Matter / Q000473:pathology / Q000503:physiopathology*