Arridge, Simon Robert; (1990) Data structures and algorithms for manipulation and display in computer simulated surgery. Doctoral thesis (Ph.D), UCL (University College London).

Text Data_structures_and_algorithms.pdf Download (18MB)

Abstract

This thesis describes the development of a computer graphics facility, referred to as UCL3D, for the planning, simulation and evaluation of Maxillo-Facial surgery on a conventional super-minicomputer, with a colour graphics framestore. The introduction defines the requirements as data acquisition, preprocessing, visualisation, dissection, manipulation, quantification, and registration. The principle innovations are in the visualisation, dissection and manipulation stages. The first part of the thesis is concerned with basic definitions and a review of other work. The data acquisition is assumed to be from a medical imaging device that produces a 3D digital array of density values. The preprocessing stage involves interpolation, artefact removal, subregioning, and segmentation. The computer representation of discrete objects from medical 3D data is discussed, and the need to have a volume based representation is justified. The implementation of UCL3D is in terms of octrees, although the principles could be applied to other representations. Both a binary and grey-value implementation have been developed, and for each case, a new structure variation is described. Visualisation is discussed in terms of these representations and surface shading techniques appropriate to each are introduced. A new algorithm for deriving the quadtree projection of an octree in orthogonal directions is presented, and its advantages explained. The concept of a general volume mask, specified interactively, is introduced for the dissection problem. The space partitioning resulting from this mask is more general than previous methods. Manipulation is considered as the combination of Boolean operations and translation and rotations, acting on combinations of dissected objects. The philosophy is to cut and merge medical objects to simulate the "osteotomies" encountered in surgery. Boolean expressions of objects may be visualised prior to being created. A description of the application of the system to several clinical cases is given and finally several areas for future work are suggested.

Download activity - last month

Export as CSVJSONXML

Download activity - last 12 months

Export as XMLJSONCSV

Downloads by country - last 12 months

Export as CSVJSONXML

Archive Staff Only

View Item