Section: New Results
Ontology-based mesh segmentation
Participants : Sahar Hassan, Franck Hétroy.
Patient-specific 3D virtual models of anatomical organs are becoming more and more useful in medicine, for instance for diagnosis or follow-up care purposes. These models are usually created from 2D scan or MRI images. However, small or thin geometrical features, such as ligaments, are sometimes not visible on these images. We propose to use an anatomical ontology, called MyCorporisFabrica http://www.mycorporisfabrica.org/ , to add missing parts to reconstructed virtual organs. This ontology describes definitions of and relationships between organs: e.g., femur is part of the leg. The first step towards the full achievement of this process is to segment virtual models, often represented by 2D meshes, into meaningful parts. In our case, “meaningful” means “related to the ontology”: each part should refer to an organ defined in the ontology. An algorithm to decompose a given organ into sub-organs according to the ontology has been proposed in the PhD thesis of Sahar Hassan  : first, we approximate organ shapes by geometric primitives, then we segment a given organ mesh by optimizing objective functions which are related to these primitives.