Description of the thesis topic

Osteoporosis diagnosis relies heavily on imaging and bone quality measurements. Current techniques, such as DXA, often fail to provide a full understanding of bone mechanical properties. Ultrasound methods, particularly those leveraging ultrasonic guided waves, have emerged as innovative, non-invasive and cost-effective alternatives for assessing bone properties. Despite recent advances, challenges in analyzing complex wave interactions within the cortical bone limit the clinical applicability of these methods.
This Ph.D. project addresses these challenges by proposing a comprehensive approach to characterize cortical bone properties. The research includes developing inversion techniques and a custom ultrasonic multielement probe to accurately determine bone quality markers, such as cortical thickness, density, and mechanical properties, essential for early-stage osteoporosis diagnosis.

Objectives:
1. Design and optimize low-frequency guided-wave ultrasound techniques to measure cortical bone properties.
2. Develop advanced inversion algorithms that integrate wave dispersion and amplitude information.
3. Design and prototype a novel multielement ultrasonic probe tailored for axial transmission applications.
4. Validate the methodology and probe in laboratory-controlled experiments using synthetic bone models and in preliminary clinical trials.

Expected Contributions:
• Development of novel computational models of the bone waveguide leveraging iso-geometric analysis (SAIGA) for accurate guided-wave simulation and inversion.
• Prototyping a scalable ultrasonic probe system optimized for clinical deployment.
• Validation of inversion algorithms through synthetic and experimental setups, minimizing discrepancies with gold-standard techniques.

Work Context

Host institutions:
Collaborative research between École de Technologie Supérieure (Montréal) and the Multiscale Modeling and Simulation Lab (CNRS, Créteil), leading institutions specializing in ultrasonic and biomedical applications.

Constraints and risks

The candidate will spend 50% of the time in Montréal and 50% in Créteil.