Evidence map›Paper›PMID 42185748›Full record

ArticleMovement disorders : official journal of the Movement Disorder Society2026

Gray Matter Microstructure Measured Using Diffusion Imaging as a Biomarker of Severity in Lewy Body Diseases.

Angeliki Zarkali, Ivelina Dobreva, Naomi Hannaway, Rohan Bhome, George E C Thomas, Steffani Carrera, Amanda J Heslegrave, Elena Veleva, Henrik Zetterberg, Rimona S Weil

Abstract read
In one paragraph

Article in Movement disorders : official journal of the Movement Disorder Society, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

Angeliki ZarkaliDementia Research Centre, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.ORCID https://orcid.org/0000-0003-2808-072X
Ivelina DobrevaDementia Research Centre, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.ORCID https://orcid.org/0000-0002-9401-1899
Naomi HannawayDementia Research Centre, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.ORCID https://orcid.org/0000-0001-8608-7757
Rohan BhomeDementia Research Centre, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.ORCID https://orcid.org/0000-0002-8317-7930
George E C ThomasDementia Research Centre, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.
Steffani CarreraDementia Research Centre, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.
Amanda J HeslegraveUK DRI Fluid Biomarker Lab and Biomarker Factory, University College London, London, United Kingdom.
Elena VelevaUK DRI Fluid Biomarker Lab and Biomarker Factory, University College London, London, United Kingdom.
Henrik ZetterbergDementia Research Centre, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.
Rimona S WeilDementia Research Centre, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.ORCID https://orcid.org/0000-0002-5092-6325

Funding

Academy of Medical SciencesParkinson's UKRosetrees TrustUK Research and Innovation UKRI2343Wellcome TrustWellcome Trust 225263/Z/22
6 · The paper itself

Abstract

backgroundDespite widespread cortical involvement in Lewy body diseases, conventional gray matter magnetic resonance imaging (MRI) shows limited sensitivity. Diffusion-weighted MRI-derived microstructural measures have shown utility in Alzheimer's disease, but their application across the Lewy body disease spectrum remains limited.

objectivesThe goal was to examine gray matter microstructure in 197 participants across the Lewy body disease spectrum (88 Lewy body dementia [LBD], 109 Parkinson's disease, and normal cognition [PD-NC]) and 46 controls.

methodsTissue-weighted neurite density index, tissue-weighted orientation dispersion index, and free water fraction were examined across 200 cortical and 32 subcortical regions. We compared these cross-sectionally between LBD, PD-NC and controls, and longitudinally over 3 years in a subset of 100 patients with Parkinson's disease cognitively intact at baseline. We assess associations with disease severity and plasma p-tau217 levels.

resultsLBD showed widespread cortical and subcortical increases in free water fraction and, to lesser extent, orientation dispersion compared to controls and PD-NC, despite minimal atrophy and no neurite density differences. In temporoparietal regions, increases in free water fraction and orientation dispersion correlated with cognitive, but not motor, severity, and with plasma p-tau217. Longitudinally, Parkinson's disease patients who developed cognitive impairment showed greater free water fraction increases within bilateral temporal regions, right thalamus, and right caudate.

conclusionsDiffusion-derived microstructural measures, particularly free water fraction are sensitive to early and progressive gray matter changes associated with cognitive decline in Lewy body diseases. Findings suggest microstructural disruption without overt neuronal loss and support free water fraction as a potential biomarker for disease staging and progression. © 2026 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Indexed as

Diffusion Magnetic Resonance ImagingGray MatterLewy Body DiseaseParkinson DiseaseAgedAged, 80 and overBiomarkersCross-Sectional StudiesFemaleHumansLongitudinal StudiesMaleMiddle AgedSeverity of Illness IndexBiomarkersdiffusion‐weighted imaginggray matter microstructureLewy body dementiaLewy body diseasesneuroimagingParkinson's disease

Identifiers

PMID42185748
PMCPMC13602283

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.