BRAIN MICROSTRUCTURAL CHANGES ARE RELATED TO SPECIFIC PD PHENOTYPES
| Autoři | |
|---|---|
| Rok publikování | 2020 |
| Druh | Konferenční abstrakty |
| Fakulta / Pracoviště MU | |
| Citace | |
| Popis | Objectives: Diffusion kurtosis imaging (DKI) overcomes the deficiency of DTI and gives more precise information about the microstructural properties of the tissue. Previous studies, both human and animal, suggest that DKI can serve as an early imaging biomarker for Parkinson's disease (PD). Methods: Ninety-two participants (PD-normal cognition, PD-MCI and HC) underwent neuropsychological and MRI examination. DKI data was preprocessed in FSL and DKE. Fractional anisotropy (FA) and mean/radial/axial kurtosis (MK/RK/AK) were of interest. Appropriate DTI parameterswere used for comparison. Gray matter (GM) was evaluated using the ROI analysis, whitematter (WM) using the tract-based spatial statistics (TBSS) and atrophy using the deformation-based morphometry. Results were FDR corrected. Characteristics of significant markers were evaluated by the ROC curve. Results: Performance in cognitive testing deteriorated from HC to PD-NC to PD-MCI. Between HC and PD-NC only differences in GM were detected - increased FA in substantia nigra, MK in thalamus and MK and AK in cortical GM in PD-NC. No changes in WM or gross atrophy were observed. PD-MCI showed widespread changes in WM (decreased DKI and increased DTI metrics) and gross atrophy in frontal areas compared to HC and PD-NC. PDMCI additionally showed decreased MK and AK in cortical GM, compared to PD-NC. The MK in cortical GM showed the best diagnostic accuracy (71%) for identification of PD-NC and HC. Conclusion: Our results showed that microstructural changes assessed by DKI parameters in both subcortical and cortical GM are already present in PD-NC and may reflect a-synuclein-related pathology, while widespread WM changes and both gross and microstructural GM changes suggestive of brain atrophy are characteristic of PD-MCI. We confirmed the superiority of DKI over DTI as a diagnostic biomarker of PD, but the ROC showed that the potential of DKI metrics to become an early diagnostic biomarker of PD is questionable. |