Objective: To evaluate brain structural changes of motor networks and basal ganglia volume in dystonia.To evaluate brain structural changes of motor networks and basal ganglia volume in dystonia.

Background: Dystonia is known as a network disorder. There is evidence of volumetric changes in structures associated with the traditional physiopathology, such as basal nuclei. One approach to studying the neural pathways is through tractography, which can provide insights into the structural connectivity of neural networks that may be disrupted in dystonia.

Method: 26 patients with right upper limb dystonia and 29 healthy controls underwent 3T MRI and evaluated in terms of DTI and T1 data. The XTRACT FSL tool was utilized to examine fractional anisotropy (FA) of the bilateral anterior thalamic radiation, superior thalamic radiation, superior longitudinal fasciculus, cortical spinal tract, middle cerebellar peduncle, forceps major and forceps minor. Using T1-weithed data, volunteers were also evaluated in terms of volumetric changes in bilateral Putamen, Caudate, Pallidum and Thalamus extracted using Freesurfer 7.0 volumetric segmentation.

Results: For uncorrected p-values, patients with upper limb dystonia show diminished FA volume in the right corticospinal tract relative to controls (p=0.025). Region of interest analysis of subcortical regions volume based on T1-weighted images shows that patients had diminished left caudate volume (p=0.031) and right putamen (p=0.041). However, using FDR multiple comparisons correction, no difference was observed between groups: right corticospinal tract (p=0.329), left caudate volume (p= 0.16), right putamen volume (p=0.16).

Conclusion: Our study could not replicate previous findings describing structural changes in dystonia. This could be to methodological differences, as well as the fact that we selected only patients with upper limb dystonia, as opposed to studies that included other types of dystonia. The neuroimaging analyses were conducted with the utmost rigor, utilizing the optimal preprocessing and statistical analysis methods. The nature and characteristics of structural alterations remain unclear and may vary depending on the subtype of dystonia. Therefore, additional structural studies and meta-analyses are warranted to advance our knowledge of this network disorder.

« Back to 2023 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/structural-mri-analysis-of-basal-ganglia-volume-and-white-matter-tracts-in-upper-limb-dystonia/