Recent Developments in Diffusion Tensor Imaging of Brain

Abstract

Citation ABSTRACTMagnetic Resonance Imaging (MRI) has come to be known as a unique radiological imaging modality because of its ability to perform tomographic imaging of body without the use of any harmful ionizing radiation. The radiologists use MRI to gain insight into the anatomy of organs, including the brain, while biomedical researchers explore the modality to gain better understanding of the brain structure and function. However, due to limited resolution and contrast, the conventional MRI fails to show the brain microstructure. Diffusion Tensor Imaging (DTI) harnesses the power of conventional MRI to deduce the diffusion dynamics of water molecules within the tissue and indirectly create a three-dimensional sketch of the brain anatomy. DTI enables visualization of brain tissue microstructure, which is extremely helpful in understanding various neuropathologies and neurodegenerative disorders. In this review, we briefly discuss the background and operating principles of DTI, followed by current trends in DTI applications for biomedical and clinical investigation of various brain diseases and disorders.

Longitudinal white matter microstructural changes in pediatric mild traumatic brain injury: AnA‐CAPstudy

“…Higher anterior thalamic radiation MD chronically in children with mTBI, and across time in younger children with persistent symptoms, relative to OI could reflect vasogenic edema, accumulation of extracellular liquid, or demyelination and axonal loss following the breakdown of the blood–brain barrier and degradation of the axonal membrane (Mayer et al, 2018 ; Parekh et al, 2015 ). Other common pathologies that can alter water diffusion include vascular changes, the disintegration of axonal microfilaments of neurons, and demyelination (Mayer et al, 2018 ; Parekh et al, 2015 ).…”

Primary HIV Drug Resistance among Recently Infected Cases of HIV in North-West India

“…The pol (RT region) gene sequences were submitted to the Stanford University HIV Drug Resistance Database (hivdb.stanford.edu/) version 6.0.11. Primary drug resistance and HIV subtype were determined according to the Stanford HIV database [20].…”

“…HIV subtype was determined according to the Stanford HIV database [20]. Phylogenetic tree was constructed with the neighbor-joining method within the Molecular Evolutionary Genetics Analysis program (MEGA) version 6 after multiple alignments of data by CLUSTAL X. Pairwise evolutionary distances were estimated using Kimura's two parameter method and reliability of the topologies was estimated by performing bootstrap analysis (1000 replicates).…”

Transhemispheric Diaschisis after Unilateral Focal Cerebral Ischemia Reperfusion: A Longitudinal Voxel-Based Study by MRI

“…With advances in non-invasive ultra-high field MRI, it becomes possible to capture changes in cerebral perfusion and diffusion with high temporal and spatial resolutions [18]. As such, we aimed to assess the evolution of transhemispheric diaschisis by using arterial spin labeling (ASL) [19] and diffusion tensor imaging (DTI) [20] techniques in a rat model of focal cerebral I/R. ASL is proving to be a powerful and reliable method in the study of regional CBF [21].…”

“…ASL is a non-invasive imaging technique gaining popularity in rCBF quantification [38,39]. DTI, on the other hand, becomes more accurate in in vivo estimates of cerebral tissue microstructures [20]. The use of MRI acquired water diffusion parameters such as FA (a measure of directional water diffusion) and MD (a measure of mean diffusivity of water, a surrogate marker of cerebral edema) have become popular in cerebral ischemia injury assessment [40][41][42][43].…”