Using ontologies linked with geometric models to reason about penetrating injuries

Architecture for integrating patient-specific data and canonical knowledge to reason about penetrating injury.

The Foundational Model of Anatomy (FMA). A portion of the FMA ontology is displayed using a Web interface, showing structures related to the heart. Organs and organ parts are shown in the hierarchy on the left (a “partonomy” display). Knowledge about individual organs or organ parts is shown in the panel on the right, and includes information such as adjacencies, orientation, and containment. The ontology is stored in Protégé.

Ontology (in OWL) of coronary anatomy and regional myocardial perfusion. Classes of anatomic structures are shown on the left panel, and formal definitions of the entities are shown on the right. The class “LateralPartOfWallOfLeftVentricle” is seen to be defined by six assertions, all necessary conditions for this class. Some of these assertions specify the coronary arterial branches that supply this structure.

Three-dimensional geometric model of the heart with labeled anatomic structures (shaded volumes in the geometric model correspond to anatomic structure classes in the FMA ontology). A trajectory of penetrating injury is superimposed (curved tubular shaded area). A conically-shaped region of tissue injury is predicted and displayed in the geometrical model (conically-shaped shaded region shown by arrow). We can determine the identity of injured anatomic structures and the volume of damaged organs from this geometric model. We can infer possible injuries to adjacent structures using knowledge in the FMA ontology.

OWL ontology of coronary anatomy and regional myocardial perfusion, with a new assertion that the second segment of the right coronary artery has been injured (a new class, “Segment2OfRCA” was created under “FunctionallyImpairedBloodVessel”). After automatic classification, additional impaired blood vessels are deduced (classes in light color), such as segments 3 and 4 of RCA, which are downstream from the injured segment 2 of RCA.

OWL ontology of coronary anatomy and regional myocardial perfusion, updated with the knowledge that the second segment of the right coronary artery has been injured. After automatic classification, new classes (light color) appear as subclasses of “IschemicAnatomicalEntity,” suggesting that regions of the left ventricle, right ventricle, and right atrium are ischemic as a result of the right coronary artery injury previously asserted (Fig. 5).