| Popis: |
This paper aimed to investigate the relationship between cortical folding and white matter integrity changes in Huntington’s disease. Cortical morphometry and tractography changes in three gyral based regions of interest (i.e., precentral, rostral middle frontal and superior frontal gyri) were examined. Neuroimaging data from the IMAGE-HD database comprised of 25 pre-symptomatic, 27 symptomatic and 25 healthy control individuals at three separate time points (baseline, 18-months, 30-months). Cortical morphometry measures of local gyrification index and cortical thickness were derived using Freesurfer 6.0’s longitudinal pipeline. Tractography integrity measures of fractional anisotropy, axial diffusivity and radial diffusivity were obtained using MRTrix3. Gyral-based regions of interest were identified using the Desikan-Killiany Atlas. A hierarchical regression analysis was conducted to investigate whether baseline white matter tractography could predict cortical morphometry changes. We found baseline white matter integrity measures did not predict tractography changes in any of the regions of interest. A hierarchical regression analysis was conducted to investigate whether tractography or cortical morphometry changes could predict change in clinical measures (i.e., disease burden score and the Unified Huntington’s Disease Rating Scale – total motor score) over and above group (i.e., clinical diagnosis) in the pre-symptomatic and symptomatic groups. Tractography and cortical morphometry changes did not significantly predict change in clinical measures over and above group. These findings suggest cortical morphometry changes in these brain regions may occur independently to the health of the cortico-striatal tracts leading to them. Furthermore, these changes appear to have no significant relationship to motor symptoms in HD or life-time disease exposure. |
