Octree-Path-Chain Data Structure in a Knowledge-Based ICAS forNose-Nasal Surgery in Otolaryngology

Image-guided computer-aided surgery (ICAS) contributes to the safety and success of surgical operations by means of displaying anatomical structures and showing correlative information to surgeons while they perform an operation. Based on the analysis of the requirements for ICAS, this paper proposes a new concept of a medical-knowledge-based ICAS. The traditional data structure is limited in expressing and reusing the medical knowledge such as locating an anatomical object, topological relations of anatomical objects and correlative medical attributes. This paper outlines a data structure of the octree-path-chain, which can be linked to the relational graphics of anatomical structures and text databases of medical knowledge, and be used to efficiently locate an anatomical object in a given medical-image data set. The computing complexity and the efficiency of the data structures mentioned above were analyzed in theory and tested in experiments. Here, it is revealed that the octree-path-chain is superior to traditional data structures in real-time operations such as search, retrieval and measuring.