Macro- and micro-structural insights into primary dystonia: a UK Biobank study

Area of Science:

• Neuroimaging
• Movement Disorders
• Structural MRI

Background:

• Dystonia is a hyperkinetic movement disorder linked to motor network dysfunction.
• UK Biobank provided data from over 500,000 participants, including 42,565 with brain MRI scans.
• An optimized MRI pre-processing pipeline was used to enhance data reliability.

Purpose of the Study:

• To investigate grey and white matter structural MRI changes in primary dystonia.
• To compare individuals with dystonia to an unaffected control cohort using UK Biobank data.

Main Methods:

• Identified 76 individuals with dystonia and 311 controls from UK Biobank.
• Assessed grey matter morphometrics and diffusion measures.
• Analyzed white matter diffusion tensor/kurtosis metrics, tractography, tractometry, and Neurite Orientation and Density Distribution Imaging (NODDI).

Main Results:

• Observed grey matter differences in the striatum, with higher radial kurtosis in dystonia.
• Segmental tractometry revealed localized white matter differences in the superior cerebellar peduncles and anterior thalamic radiations.
• Found higher fractional anisotropy and lower orientation distribution index in these tracts in dystonia patients.

Conclusions:

• Structural MRI analysis of a large dystonia cohort reveals white matter microstructural differences in cerebellar and thalamic connections.
• Architectural changes, like reduced orientation dispersion, may underlie morphological alterations in dystonia.
• Distinct tremor-related imaging features were identified in both grey and white matter.