Soutenance de thèse de Margot Leclercq

Identification and kinematic analysis from intraoperative imaging via projection-based digital volume correlation

Recent advances in additive manufacturing have enabled the development of tissue-mimicking materials for biomedical applications, particularly patient-specific anatomical models used in surgical training and device development. In the context of EndoVascular Aneurysm Repair (EVAR), abdominal aortic aneurysm phantoms are 3D-printed using the PolyJet process. Although these models achieve high anatomical fidelity, their mechanical reliability remains limited, restricting their use in clinical practice.
A key objective of this work is to improve the characterization of the mechanical loading conditions experienced during EVAR procedures. These interventions, performed under cone-beam CT guidance, combine pre- and post-operative 3D imaging with real-time 2D fluoroscopy, providing a rich multimodal dataset for analyzing intraoperative kinematics. This thesis investigates a projection-based digital volume correlation (P-DVC) approach to reconstruct 3D kinematics from multi-angle 2D radiographic data acquired under varying loading conditions, enabling a temporal resolution beyond that of conventional methods.
In parallel, multiaxial mechanical testing under controlled conditions is being developed to identify nonlinear constitutive laws for PolyJet materials that account for complex intraoperative loading states. The identification framework relies on inverse methods coupled with full-field measurements, supported by numerical strategies that enhance sensitivity to experimental data.
By integrating experimental and computational approaches, this work improves the mechanical modeling of 3D-printed anatomical phantoms. It opens new perspectives for their use in surgical training, complex case rehearsal, and the optimization of endovascular procedures.

 

Composition du jury :

• Aline BEL-BRUNON, Directrice de recherche, Université Gustave Eiffel, Rapportrice
• Jean-Charles PASSIEUX, Professeur des universités, INSA de Toulouse, Rapporteur
• Jean-Marc ALLAIN, Professeur des universités, École Polytechnique, Examinateur
• Clément JAILIN, Chaire de professeur junior, Université Paris-Saclay, Examinateur
• Stéphan HAULON, Professeur - Chirurgien vasculaire, Hôpital Marie Lannelongue, Examinateur