NeuroNetwork 1

Magnetic resonance imaging allows the inclusion of detailed cross-sectional images without side-effects for the patients. Especially at high magnetic field strengths more contrast mechanisms in gain importance besides the usual relaxation contrasts. The phase contrast is based on magnetic and chemical properties of tissues and has generated great interest because it shows high resolution with exceptionally high contrast, which contains complementary information. That phase contrast is maintained by ultra-high field. The exact cause of this contrast is only partially cleared and has been studied in this project with simple protein solutions, cell extractions, animal models and in patients.

A major project basis forms the water-macromolecule exchange (WME) model for in vivo phase contrast imaging (Zhong). It could be shown that macromolecules make an important contribution to the phase contrast (about 1/3 compared to magnetic susceptibility). The research network brings together research expertise in magnetic resonance imaging in ultra-high-field (Zhong), high-resolution NMR spectroscopy (Hilfert), cell biochemistry (Smalla), in vivo animal MRI (Angenstein) and clinical research of multiple sclerosis (MS) (Matzke).

The projects investigated the WME and its effects on frequency shifts of water (Zhong) and relate this microscopic effect on the macroscopic MR imaging in experiments with animals (MS mouse model) (Angenstein). In addition, the influence of various physico-chemical parameters of macromolecules and the contribution of different subcellular structures from different regions of the rat brain for in vivo phase contrast was examined (Smalla, Zhong). The potential of phase contrast as a novel diagnostic tool for early detection and prediction of disease was evaluated in MS patients (Matzke). So far physical, chemical and biochemical effects have been clarified and a new clinical classification model was proposed for the differentiated nature of MS lesions in phase contrast.