Quantification of Free and Bound Water Concentrations in Human Cortical Bone Employing Hybrid Hard-tissue MRI: Towards Comprehensive Osteoporosis Assessment

Description du projet

L’imagerie de l’eau dans les os pour diagnostiquer l’ostéoporose

L’ostéoporose entraîne une fragilisation des os et cause des millions de fractures dans le monde chaque année. La qualité de l’os est généralement évaluée par le processus de minéralisation osseuse, qui offre cependant une vision incomplète de la qualité de l’os. Le projet ROCHESTER, financé par l’UE, propose d’utiliser la teneur en eau, une source d’informations plus riche sur la porosité des os. Les chercheurs mettront au point une nouvelle technique de diagnostic basée sur l’imagerie par résonance magnétique (IRM) pour générer des biomarqueurs d’imagerie quantitative associés aux concentrations d’eau libre et liée dans l’os cortical. Le projet pourrait permettre d’améliorer le diagnostic de l’ostéoporose et l’évaluation du développement osseux en pédiatrie, réduisant ainsi la charge économique sur les systèmes de santé.

Objectif

Osteoporosis weakens bones and increases the risk of unexpected fractures. Worldwide, it causes over 8.9M fractures annually. Cortical bone consists of 3 major parts; minerals, organic matrix and water. Bone Mineral Density (BMD) is the most widespread marker to assess bone quality. There is recent evidence, however, that bone mineralisation offers only an incomplete view of bone quality. In turn, bone water (including free and bound water molecules) does convey richer information about bone quality by probing both bone porosity and the organic matrix.
We propose to develop a novel diagnostic imaging technique based on Magnetic Resonance Imaging (MRI) that offers a comprehensive assessment of cortical bone quality and osteoporosis. The quantification of free and bound water molecules in cortical bone will be done in vivo as their alternation are potential biomarkers of the cortical bone quality. We will use hybrid hard-tissue MRI to capture information from short transverse-relaxation time (T2) species. We will develop MRI
strategies that will go beyond the state-of-the-art in imaging bone tissue (herein referred to as “hard-tissue MRI” employing novel pulse sequences from the ultra-short echo-time (UTE) family. A key novelty lies in the hybridisation of UTE/short echo time (STE) acquisitions. By solving a set of coupled equations derived from these acquisitions using machine-learning techniques, we will define new quantitative imaging biomarkers associated with cortical bone free and bound water concentrations.
The biomarkers will improve diagnosis of osteoporosis and alleviate its burden on healthcare systems (€37Bn cost to EU in 2010). It offers further potential in assessing bone development in pediatric imaging where ionizing and invasive methods cannot be employed. The project brings together expertise in bone MRI from a senior incoming fellow with the world-class expertise in biomedical image analysis and bone research as well as a pioneer centre in clinical.