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Doctoral defense: Brian Hansen

CFIN researcher, Associate Professor Brian Hansen, will defend his doctoral dissertation entitled: "Experimental diffusion MRI from cellular-level microscopy to in vivo application"

12.07.2018 | Henriette Blæsild Vuust

Dato fre 07 sep
Tid 14:00 16:00
Sted Auditorium 424, Institut for Biomedicin, bygning 1231, Wilh. Meyers Allé, Universitetsparken.

Brian Hansen
"Experimental diffusion MRI from cellular-level microscopy to in vivo application"


The dissertation is based on a collection of nine scientific works. The common theme of the studies is experimental measurements with diffusion-weighted magnetic resonance (MR) scanning, often just referred to as diffusion MR, as well as analysis of the measurements based on physical theory. Diffusion MR measurements are very sensitive to the microscopic structures in biological tissues. Therefore, these techniques are a very important tool in research and clinical diagnostics, as many diseases first result in changes in the microscopic structure of the tissue - often even before actual symptoms of disease develop.

The thesis' focus is primarily on the development of methods and their use in the scanning of the brain, where the coupling between microstructure and function is very strong. Due to the sensitivity of the methods - and because MR scanning is generally considered harmless - much research aims at developing new diffusion MR methods as well as improving existing methods. The goal is that the techniques should be applicable for diagnosis of patients. In addition, diffusion MRI can be used as a research tool to illuminate biological mechanisms in humans and animals, thereby improving our overall understanding of the brain (but also other organs of the body e.g. kidney as demonstrated in one of the presented studies). To achieve this, the sensitivity and specificity of the methods must be improved, and an in-depth understanding of how the methods reflect disease must be established. Furthermore, the methods must be time-efficient so that they can easily be included in daily clinical work. The dissertation touches on all of these topics.

The experimental work was performed using a diverse range of field strengths (from 3T to 17T) and in many cases make use of advanced prototype equipment. All studies are based on physics but with a clear biological / medical aim. Overall, the included studies illustrate the information content in diffusion MR measurements, and the studies contribute with sensitive methods that are fast enough to be included in, for example, the acute study of stroke or head trauma, and which can also be used to follow disease development or treatment effect.

Together with collaborators at home and abroad, the methods have been used in studying brain tumors, concussion, stress, drug abuse, and multiple sclerosis. The increase in life expectancy among the Danes, and the resulting illnesses put pressure on the health sector. This challenge is not solved with technology alone, but it is certainly not overcome without technology. Hopefully, some of the described techniques will find use both as research tools and as effective diagnostic tools in the future health care system.

Electronic version of the dissertation available on request to brian@cfin.au.dk


Arrangement, Sundhed og sygdom, Videnskabelig medarbejder, CFIN, CFIN, Ph.d.-studerende, Musicinthebrain, Forskningsårsstuderende, Kommende studerende, Teknisk/administrativ medarbejder