The purpose of this article is to explain how the random walks of water molecules undergoing diffusion in living tissue may be exploited to garner information on the white matter of the human brain and its connections. We discuss the concepts underlying diffusion-weighted (DW) imaging, and diffusion tensor imaging before exploring fibre tracking, or tractography, which aims to reconstruct the t...

This paper and Part 1 which appeared in the last issue, set out the results of a housing field trial designed to evaluate the impact of an enhanced energy performance standard for dwellings. The project was designed to inform the next review of Part L of the Building Regulations for England and Wales, which, following the publication of the UK government’s white paper on energy policy (DTI, 200...

In the last decade, several studies have described the typical brain white matter maturation in children and adolescents. Diffusion tensor imaging (DTI) is the most frequent MRI technique used to investigate the structural changes across development. However, few previous studies have used the magnetization transfer ratio (MTR), which gives a closer measure of myelin content. Here, we employed ...

J. Nogee, B. S. Stone, D. W. Mack, L. J. Martin, M. I. Miller, S. Mori, F. J. Northington, and J. Zhang Johns Hopkins University School of Medicine, Baltimore, MD, United States, Pediatrics, Johns Hopkins University School of Medicine, Pathology, Johns Hopkins University School of Medicine, Center of Imaging Science, Johns Hopkins University, Radiology, Johns Hopkins University School of Medici...

This work reviews magnetic resonance imaging in the developing human brain. It focuses on fetal brain imaged in vivo and in utero with complementary sections on abnormalities seen in clinical settings, and on potential of diffusion tensor imaging and of proton magnetic resonance spectroscopy. The main purposes are to illustrate the normal fetal developing brain and its abnormalities commonly en...

Introduction Diffusion tensor imaging reveals detailed structural information about white matter tracts, and is increasingly used to study the pediatric population. It is highly desirable to construct age appropriate templates so the findings in patients could be reported using coordinates in a standard stereotaxic brain space, and at all brain locations the diffusion measures of an individual ...

The tensors produced by diffusion tensor magnetic resonance imaging (DTMRI) represent the covariance in a Brownian motion model of water diffusion. Under this physical interpretation, diffusion tensors are required to be symmetric, positive-definite. However, current approaches to statistical analysis of diffusion tensor data, which treat the tensors as linear entities, do not take this positiv...

Diffusion tensor imaging provides the ability to study white matter connectivity and integrity noninvasively. The information contained in the diffusion tensors is very complex. Therefore a simple way of dealing with tensors is to compute rotationally invariant scalar quantities. These scalar indices have been used to perform population studies between controls and patients with neurological an...

The aim of the present study was to evaluate a fast clinical protocol to enable diffusion tensor imaging of the human forearm and assess the reproducibility of six diffusion tensor imaging parameters, i.e., the tensor eigenvalues (λ(1), λ(2), and λ(3)), mean diffusivity, fractional anisotropy, and ellipsoid eccentricity. The right forearms of 10 healthy volunteers were scanned twice, with a 1-w...

Assessment of the integrity of the articular cartilage is considered key for the early diagnosis of osteoarthritis (OA). Diffusion-weighted imaging and diffusion tensor imaging have potential as biomarkers for cartilage composition and structure. The value of diffusion to detect compositional and structural changes in the cartilage matrix has been shown in ex vivo experiments for several years....