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...

This paper presents a new method for warping of diffusion tensor fields. The proper reorientation of a tensor field requires knowledge of the underlying fiber orientation, which is not known a priori. Accordingly, a probabilistic representation of the fiber direction is adopted and used in a Procrustean estimation of the rotational component of the warping field. The estimated rotational compon...

Diffusion tensor imaging (DTI) is a magnetic resonance imaging technique that in vivo visualises random translational movement of water molecules. DTI has inherent difficulties with low signal-to-noise ratio, sensitivity to patient motion, field inhomogeneities and fast T2 relaxation. It has been used in the central nervous system, although it has not been assessed in the peripheral nervous sys...

Diffusion-weighted imaging (DWI) provides a method of noninvasive tissue characterization that is unique and complementary to other imaging techniques. Diffusion tensor imaging (DTI) and DTI-based fiber tracking (“tractography”) have enabled unprecedented, in vivo visualization of individual WM tracts and their relationships with cerebral pathology. DWI has already revolutionized the imaging of...

Diffusion tensor imaging is highly sensitive to the microstructural integrity of the brain and has uncovered significant abnormalities following traumatic brain injury not appreciated through other methods. It is hoped that this increased sensitivity will aid in the detection and prognostication in patients with traumatic injury. However, the pathological substrates of such changes are poorly u...

Diffusion of molecules in brain and other tissues is important in a wide range of biological processes and measurements ranging from the delivery of drugs to diffusion-weighted magnetic resonance imaging. Diffusion tensor imaging is a powerful noninvasive method to characterize neuronal tissue in the human brain in vivo. As a first step toward understanding the relationship between the measured...

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...

Diffusion Tensor Magnetic Resonance Imaging (DT-MRI or DTI) is emerging as an important technology for elucidating the internal structure of the brain and for diagnosing conditions affecting the integrity of nervous tissue. DTI measurements of the brain exploit the fact that the network of fibers has a characteristic microstructure that constrains the diffusion of water molecules within it. The...

S. Xu, G-H. Jahng, N. Schuff, D. J. Meyerhoff, and M. W. Weiner Department of Medical Research Center, Kyung-Hee University, Seoul, Seoul, Korea, Republic of, Radiology, East West Neo Medical Center, Kyung Hee University, Seoul, Seoul, Korea, Republic of, Radiology, CIND, Veterans Affairs Medical Center, UCSF, San Francisco, CA, United States, Radiology, CIND, Veterans Affairs Medical Center, U...