Diffusion Kurtosis Imaging in Neurological Disorders

Diffusion kurtosis imaging (DKI) is an advanced magnetic resonance technique that extends conventional diffusion tensor imaging by quantifying the non-Gaussian behaviour of water diffusion in brain tissue. By capturing the degree of complexity and heterogeneity in microstructural environments, DKI offers enhanced sensitivity to subtle alterations in white and grey matter organisation that often accompany stroke, neurodegenerative diseases, mild cognitive impairment and demyelinating disorders. Metrics such as mean kurtosis and kurtosis fractional anisotropy provide complementary information to diffusivity and anisotropy measures, enabling more detailed characterisation of axonal integrity, myelin disruption and fibre-crossing regions. In clinical settings, DKI has been applied to detect early microstructural changes in Alzheimer’s disease, monitor white matter damage after traumatic brain injury and elucidate pathological mechanisms in systemic lupus erythematosus, demonstrating its potential as a biomarker for diagnosis, prognosis and treatment monitoring.

Research from Nature Portfolio

Recent studies have demonstrated that kurtosis fractional anisotropy (KFA) supplements conventional anisotropy measures by revealing contrast in regions of complex fibre architecture where fractional anisotropy (FA) may fail. Investigations in both ex vivo and in vivo models established a rapid proxy estimation for KFA that achieves high correlation with full sampling methods, offering a practical route to incorporate kurtosis anisotropy into routine protocols without prohibitive scan times. In parallel, high spatial resolution DKI has been shown to exhibit excellent test–retest reliability in clinical scanners, with coefficients of variation under 5 per cent for key kurtosis and tensor metrics even in traumatically injured brains. These findings underscore the technical robustness of advanced diffusion protocols and encourage their adoption for longitudinal studies in patient populations.

Diffusion Kurtosis Imaging in Neurological Disorders publication trend

The graph below shows the total number of articles in diffusion kurtosis imaging in neurological disorders across all publications each year (not limited to Nature Index journals).

Technical terms

Diffusion kurtosis imaging (DKI): An MRI method that characterises the departure of water molecule diffusion from a Gaussian distribution, providing metrics of tissue complexity.

Mean kurtosis (MK): A scalar measure of overall non-Gaussian diffusion within a voxel, reflecting microstructural heterogeneity.

Fractional anisotropy (FA): A tensor-derived metric quantifying the directional dependence of water diffusion, indicative of fibre alignment and integrity.

Kurtosis fractional anisotropy (KFA): A scalar index capturing anisotropy in diffusion kurtosis, offering contrast where traditional FA is diminished.

Tract-based spatial statistics (TBSS): A voxel-wise analysis framework for comparing diffusion metrics along a common white matter skeleton across subjects.

References

1. Kurtosis fractional anisotropy, its contrast and estimation by proxy. Scientific Reports (2016).
2. Test-retest reliability of high spatial resolution diffusion tensor and diffusion kurtosis imaging. Scientific Reports (2017).
3. Robust, fast and accurate mapping of diffusional mean kurtosis. eLife (2024).
4. Diffusion kurtosis imaging of brain white matter alteration in patients with coronary artery disease based on the TBSS method. Frontiers in Aging Neuroscience (2024).
5. Microstructural changes of the white matter in systemic lupus erythematosus patients without neuropsychiatric symptoms: a multi-shell diffusion imaging study. Arthritis Research & Therapy (2024).