About this Research Topic
Recent advances in diffusion weighted (DW) magnetic resonance imaging (MRI) provided non-invasive, in vivo means for assessment of white matter integrity in human subjects. The novel mathematical approaches of data analysis and visualization made possible the use of DWI to study white matter integrity along with nerve fiber connections.
Accordingly, recent tractography studies of several diseases and
disorders unveiled information about nerve fiber pathways and white matter integrity. This has significantly improved guidance
potential for diagnosis, prognosis and treatment of acute and
chronic symptoms in neurological diseases and psychiatric disorders such as stroke, multiple sclerosis, epilepsy, Alzheimer’s disease, Parkinson’s disease, schizophrenia, depression and traumatic brain injury (TBI).
A majority of tractography methods are based on diffusion tensor (DT) model which is limited in describing complex tissue structure such as the nerve fiber junctions. In addition, the constraints of higher order analysis methods, such as symmetry, prevent innately an elaborate description of biological tissue microstructure due to information loss/deterioration. These raise the concern about the
sufficiency and the accuracy of white matter integrity/pathology information and metrics obtained with current methods.
Consequently, after achieving the proof of utility, DW-MRI
methodologies are currently open for improvements and refinements.
The purpose of this Research Topic is to investigate new analysis
methods and new mathematical models with possible introduction of new acquisition techniques. This will be achieved by returning to the first principles of DW-MRI signal formation in order to explore new horizons that remained veiled due to constraints and boundaries imposed by existing methodologies. Particular emphasis will be given to approaches that will allow unconstrained evidence based discoveries using DW-MRI signal. Biological, synthetic and numerical phantoms created for test and validation purposes are highly encouraged.
In parallel, physiological description of white matter integrity disruption and its reflection on DW-MRI signal is central to the theme of the Research Topic.
The aim is geared up towards the identification of the nerve fiber DW-MRI signal, separating the portion of the signal from other elements within biological tissue, whereby an accurate calculation of surrogate markers/descriptors of white matter integrity would be achieved. Accordingly, comparison and/or combination of alternative MRI methods (e.g. susceptibility imaging) with DW-MRI are in focus of interest and are highly welcomed.