Multiscale Elastography for Characterization of Pathologic Extracellular Matrix Change

Multi-frequency magnetic resonance elastography (mMRE) measures the dispersion of viscoelasticity in soft tissues and is therefore sensitive to extracellular matrix (ECM) and cellular micromechanical interactions. In the first funding phase, we developed mMRE techniques that operate at various magnetic field strengths ranging from 0.5 to 7 Tesla, in order to cover a broad range of mechanical excitation frequencies for a comprehensive analysis of the viscoelastic properties of normal and diseased biological tissue. Using this innovative multimodal mMRE technology, we have demonstrated that the degradation of the ECM due to inflammatory processes or the accumulation of fibrous proteins is accompanied by significant changes in the internal mechanical friction of soft tissue. The mechanical friction leading to viscoelastic dispersion thus represents a sensitive probe for mMRE-based diagnosis that goes beyond fibrosis-related tissue stiffening. 

Initial clinical trials to quantify dispersion using mMRE have been conducted in patients with inflammatory bowel disease, nephritis, pancreatitis, hepatitis, liver fibrosis and cancer. For the next funding phase, we plan to further increase the sensitivity of MRE to viscous dispersion by extending the dynamic range of mMRE to ultra-low and ultra-high frequencies. We and others have provided initial evidence that ultra-low frequencies in MR.

The project is led by Prof. Dr Ingolf Sack and Prof. Dr Anja Hennemuth as part of SFB 1340 at Charité – Universitätsmedizin Berlin.