Our specific task is optimizing the acquisition of diffusion MRI imaging of in vivo tongue muscles, which we then validate against diffusion spectrum imaging of the post-mortem tongue and histology to verify true muscle alignment. Further we want to establish strain measures in the line of action of tongue muscle fibers using in vivo tagged MRI and diffusion MRI; develop models of functional connectivity in the tongue during speech; and assess tongue strategies in post-glossectomy speech

1. Motion detection and elimination in diffusion MRI

Phase Image Texture Analysis for Motion Detection in dMRI (PITA-MDD) method applied to detect motion in the tongue (e.g. during swallowing) and improve fiber tracking results. 

2. Diffusion tractography and histology verification in the tongue

Here we develop and optimize an MPRAGE technique to generate a series of T1-based synthetic MPRAGE (SynMPRAGE) for direct visualization of sub-thalamic nuclei. Image shows T1map and SynMPRAGE images in coronal and sagittal planes with varied inversion times (TI’s of 520ms, 660ms, 800ms) for intra-thalamic nuclei visualization, as compared to the 7T visualization and the Morel Atlas (adapted from Tourdias et al). 

Conventional CT or MRI has limited sensitivity in detecting the diffuse axonal injury typically associated with TBI. Here we used different advanced MRI tools (DTI/DKI, resting state fMRI, proton MR spectroscopy) to study the structural and functional changes in the brain following TBI.

The figure below shows Diffusion Kurtosis Imaging that denotes distinct features in changes of diffusion heterogeneity.