PhD student Andrey Chuhutin from the Neurophysics Group at CFIN is defending his PhD thesis on “Characterisation of microstructural degeneration with diffusion MRI”. In his thesis Andrey has explored microstructural biomarkers yielded by diffusion MRI and biophysical modelling and assessed the specificity and sensitivity of these biomarkers using animal models of stress and multiple sclerosis (MS).

17.01.2019 | Henriette Blæsild Vuust

Magnetic resonance imaging (MRI) scans have recently become part of the diagnostic criteria for MS. However, despite substantial progress in the last decade, MRI techniques currently used in clinic lack specificity and sensitivity and are generally poorly correlated with disease load.

Diffusion tensor imaging (DTI) and its expansion diffusion kurtosis imaging (DKI) are imaging modalities that are sensitive to the displacement of water molecules in the tissue and share the ability to provide contrast based on microstructural anatomy of neural tissue. While DTI assumes Gaussian distribution of the displacements, which is valid only in the limited regime of low diffusion weighting, DKI provides non-Gaussian metrics.

In his thesis Andrey Chuhutin examined the interconnection between DKI-based biomarkers, microstructural modelling parameters and neural tissue microstructure, and explored factors that influence the sensitivity and specificity of parameter estimation. Applicability of related metrics was evaluated using the experimental autoimmune encephalomyelitis (EAE) model of MS. He discussed microstructural models, their area of applicability and added value as well as relationship to data models of MRI signal.

The results have shown a high potential and applicability of DKI for a quantitative assessment of neural tissue. First two studies aimed on choosing biomarkers that are specific to tissue microstructure and establishing a protocol that would allow a sensitive measurement of these biomarkers. In the third study a combination of changes was measured in EAE animals ex-vivo using these protocols. The uncovered relationship of the microstructural biomarkers to the modelled pathology can open new avenues in diagnosis and non-invasive monitoring of disease progression and treatment effect in MS patients along with a range of other brain diseases.

The defence is public and will take place in the Palle Juul-Jensen Auditorium, Aarhus Universitetshospital, Building 10G, Nørrebrogade 44, 8000 Aarhus C.

ALL ARE WELCOME

For more details please contact Andrey Chuhutin at andrey@cfin.au.dk or +4542837117.
An electronic version of the thesis is available on request.