Dataset Information

Thalamic atrophy in frontotemporal dementia - Not just a C9orf72 problem.

ABSTRACT:

Background

Frontotemporal dementia (FTD) is a heterogeneous neurodegenerative disorder associated with frontal and temporal atrophy. Subcortical involvement has been described as well, with early thalamic atrophy most commonly associated with the C9orf72 expansion. However thalamic involvement has not been comprehensively investigated across the FTD spectrum.

Methods

We investigated thalamic volumes in a sample of 341 FTD patients (age: mean(standard deviation) 64.2(8.5) years; disease duration: 4.6(2.7) years) compared with 99 age-matched controls (age: 61.9(11.4) years). We performed a parcellation of T1 MRIs using an atlas propagation and label fusion approach to extract left and right thalamus volumes, which were corrected for total intracranial volumes. We assessed subgroups stratified by clinical diagnosis (141 behavioural variant FTD (bvFTD), 76 semantic dementia (SD), 103 progressive nonfluent aphasia (PNFA), 7 with associated motor neurone disease (FTD-MND) and 14 primary progressive aphasia not otherwise specified (PPA-NOS), genetic diagnosis (24 with MAPT, 24 with C9orf72, and 15 with GRN mutations), and pathological diagnosis (40 tauopathy, 61 TDP-43opathy, 3 FUSopathy). We assessed the diagnostic accuracy based on thalamic volume.

Results

Overall, FTD patients had smaller thalami than controls (8% difference in volume, p?C9orf72 group had the smallest thalami (14% difference from controls, p?GRN and MAPT groups showed a difference of 11% and 9% respectively (p?C9orf72 from MAPT (AUC?=?0.651, p?=?0.073) and from GRN cases (AUC?=?0.644, p?=?0.133) using thalamic volume. All clinical subtypes had significantly smaller thalami than controls (p?GRN, PPA-NOS and SD were the subgroups showing the highest asymmetry in volumes.

Conclusions

The thalamus was most affected in C9orf72 genetically, TDP-43opathies pathologically and FTD-MND clinically. However, thalamic atrophy is a common feature across all FTD groups.

SUBMITTER: Bocchetta M

PROVIDER: S-EPMC5988457 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Thalamic atrophy in frontotemporal dementia - Not just a <i>C9orf72</i> problem.

Bocchetta Martina M Gordon Elizabeth E Cardoso M Jorge MJ Modat Marc M Ourselin Sebastien S Warren Jason D JD Rohrer Jonathan D JD

NeuroImage. Clinical 20180223

<h4>Background</h4>Frontotemporal dementia (FTD) is a heterogeneous neurodegenerative disorder associated with frontal and temporal atrophy. Subcortical involvement has been described as well, with early thalamic atrophy most commonly associated with the <i>C9orf72</i> expansion. However thalamic involvement has not been comprehensively investigated across the FTD spectrum.<h4>Methods</h4>We investigated thalamic volumes in a sample of 341 FTD patients (age: mean(standard deviation) 64.2(8.5) ye ...[more]

PMID: 29876259

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