Thalamic Nuclei Segmentation Using Tractography, Population-Specific Priors and Local Fibre Orientation

The thalamus is a deep grey matter structure that plays an important role in propagating nerve impulses between subcortical regions and the cerebral cortex. It is composed of distinct nuclei that have unique long-range connectivity. Accurate thalamic nuclei segmentation provides insights about structural connectivity and the neurodegeneration mechanisms occurring in distinct brain disorders, for instance Alzheimer’s disease and Frontotemporal dementia (FTD). In this work, we propose a novel thalamic nuclei segmentation approach that relies on tractography, thalamic nuclei priors and local fibre orientation. Validation was performed in a cohort of healthy controls and FTD patients against other thalamus connectivity-based parcellation methods. Results showed that the proposed strategy led to anatomical plausible thalamic nuclei segmentations and was able to detect connectivity differences between controls and FTD patients.