The central nervous system (CNS) spans across different levels of organization, covering the gamut from genes to behavior. It is the aim of neuroscience to elucidate all these levels at a gross and an ultrastructural resolution and to define the relationships among them. One of the highest levels of organization is the systems level, which includes the motor, sensory, and central neural systems...

Diffusion tensor MRI (DT-MRI) is the only non-invasive method for characterising the microstructural organization of tissue in vivo. Generating parametric maps that help to visualise different aspects of the tissue microstructure (mean diffusivity, tissue anisotropy and dominant fibre orientation) involves a number of steps from deciding on the optimal acquisition parameters on the scanner, col...

PURPOSE To prospectively evaluate several diffusion-tensor magnetic resonance (MR) imaging indexes (mean diffusivity [MD], fractional anisotropy [FA], and eigenvalues) of corticospinal tract impairment in patients with progressive muscular atrophy (PMA) and patients with amyotrophic lateral sclerosis (ALS). MATERIALS AND METHODS This study had institutional review board approval, and written ...

Introduction The observation of non-monoexponential decay of diffusion-weighted MR signals with b-value has been widely reported [1]. Using the theory of anomalous diffusion, several groups have derived a stretched-exponential form for this signal decay (e.g. [2][3]) which parameterises the signal in terms of a distributed diffusivity α (measuring the overall rate of diffusion) and an anomalous...

In diffusion tensor imaging (DTI) an effective diffusion tensor in each voxel is measured by using a set of diffusion-weighted images (DWIs) in which diffusion gradients are applied in a multiplicity of oblique directions. However, to estimate the diffusion tensor accurately, one must account for the effects of all imaging and diffusion gradient pulses on each signal echo, which are embodied in...

PURPOSE Diffusion tensor imaging (DTI) is known to suffer from long acquisition time in the orders of several minutes or even hours. Therefore, a feasible way to accelerate DTI data acquisition is highly desirable. In this article, the feasibility and efficacy of distributed compressed sensing to fast DTI is investigated by exploiting the joint sparsity prior in diffusion-weighted images. MET...

In this paper we present a mathematical and numerical framework for a procedure of imaging anisotropic electrical conductivity tensor by integrating magneto-acoutic tomography with data acquired from diffusion tensor imaging. Magneto-acoustic Tomography with Magnetic Induction (MAT-MI) is a hybrid, non-invasive medical imaging technique to produce conductivity images with improved spatial resol...