Format

Send to

Choose Destination
J Alzheimers Dis. 2016;49(3):633-43. doi: 10.3233/JAD-150502.

Characterizing White Matter Tract Degeneration in Syndromic Variants of Alzheimer's Disease: A Diffusion Tensor Imaging Study.

Author information

1
Department of Radiology, Mayo Clinic, Rochester, MN, USA.
2
Department of Neurology (Speech Pathology), Mayo Clinic, Rochester, MN, USA.
3
Department of Psychiatry and Psychology (Neuropsychology), Mayo Clinic, Rochester, MN, USA.
4
Department of Neurology (Behavioral Neurology), Mayo Clinic, Rochester, MN, USA.
5
Department of Health Sciences Research (Biostatistics), Mayo Clinic, Rochester, MN, USA.
6
Department of Information Technology, Mayo Clinic, Rochester, MN, USA.
7
Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA.

Abstract

BACKGROUND:

Different clinical syndromes can arise from Alzheimer's disease (AD) neuropathology, including dementia of the Alzheimer's type (DAT), logopenic primary progressive aphasia (lvPPA), and posterior cortical atrophy (PCA).

OBJECTIVE:

To assess similarities and differences in patterns of white matter tract degeneration across these syndromic variants of AD.

METHODS:

Sixty-four subjects (22 DAT, 24 lvPPA, and 18 PCA) that had diffusion tensor imaging and showed amyloid-β deposition on PET were assessed in this case-control study. A whole-brain voxel-based analysis was performed to assess differences in fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity across groups.

RESULTS:

All three groups showed overlapping diffusion abnormalities in a network of tracts, including fornix, corpus callosum, posterior thalamic radiations, superior longitudinal fasciculus, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, and uncinate fasciculus. Subtle regional differences were also observed across groups, with DAT particularly associated with degeneration of fornix and cingulum, lvPPA with left inferior fronto-occipital fasciculus and uncinate fasciculus, and PCA with posterior thalamic radiations, superior longitudinal fasciculus, posterior cingulate, and splenium of the corpus callosum.

CONCLUSION:

These findings show that while each AD phenotype is associated with degeneration of a specific structural network of white matter tracts, striking spatial overlap exists among the three network patterns that may be related to AD pathology.

KEYWORDS:

Alzheimer’s disease; diffusion tensor imaging; logopenic; posterior cortical atrophy; white matter

PMID:
26484918
DOI:
10.3233/JAD-150502
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for IOS Press
Loading ...
Support Center