Automatic segmentation of thalamic nuclei from diffusion tensor magnetic resonance imaging

The nuclei of the thalamus have traditionally been delineated by their distinct cyto/myeloarchitectural appearance on histology. Here, we show that diffusion tensor magnetic resonance imaging (DTI) can noninvasively resolve the major thalamic nuclei based on the characteristic fiber orientation of the corticothalamic/thalamocortical striations within each nucleus. Using an automatic clustering algorithm, we extracted the Talairach coordinates for the individual thalamic nuclei. The center-of-mass coordinates for the segmented nuclei were found to agree strongly with those obtained from a histological atlas. The ability to resolve thalamic nuclei with DTI will allow for morphometric analysis of specific nuclei and improved anatomical localization of functional activation in the thalamus. (C) 2003 Elsevier Science (USA). All rights reserved.