The aim of this review article was to introduce the basic principles of diffusion tensor imaging (DTI) and to present its potential clinical applications. DTI is a non-invasive magnetic resonance technique, which measures the self-diffusion characteristics of water and provides an estimate of the orientation of fibre bundles in the white matter of the brain. The degree of directionality of diffusion can be expressed as fractional anisotropy, which is a sensitive parameter to measure microstructural changes in white matter. Generally, DTI can provide four categories of new information: new contrasts, white matter morphology, refined information about anatomical locations, and connectivity.
The main indications for DTI clinical application are brain tumours, stroke, hypoxic-ischaemic encephalopathy, developmental abnormalities, neurodegenerative diseases, multiple sclerosis, psychiatric conditions, traumatic brain injuries, etc. Dynamic DTI studies enable to estimate rehabilitation process, as well as to follow the course of neurodegenerative diseases. DTI is also widely used for research. Fibre tracking in combination with functional MRI may provide new information about connectivity and anatomical-functional relationships of the brain structures.