Connectivity analysis of anterior nuclei of the thalamus in diffusion-MRI using constrained spherical deconvolution (CSD), multi-shell multi-tissue CSD and probabilistic DTI for ANT-DBS in epilepsy

摘要

The anterior nuclei of the thalamus (ANT) have been a promising target in order to control and reduce epileptic seizuresfor deep brain stimulation surgery (DBS). There are several theories on the structural connectivity of ANT, but clearevidence is still missing. The clinical studies show that each subdivision of the ANT presents different patterns ofconnectivity throughout the hippocampus, mammillary bodies, and neocortex. Diffusion MRI is a well-known techniquethat non‐invasively investigates the microstructural organization and orientation of biological tissues in vivo. Diffusiontensor imaging (DTI) is one of the models that has been widely accepted in order to examine the human brain, although itdoes not accurately reveal the fiber orientations of complex structures due to the presence of crossing fibers. Constrainedspherical deconvolution (CSD) can be used to reveal the fiber orientations, overcoming the limitations of DTI. Recentstudies show that the b value and gradient directions also play a significant role in extracting fiber orientations in suchcomplex structures. These methods enable a more accurate tractography and investigation of the structural connectivity.In this paper, we demonstrate an approach for the connectivity analysis of ANT by determining different ROIs in the Papezcircuit.