Adaptive surface data compression

Surgical Planning Laboratory, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA; Telecommunications Institute, University of Erlangen-Nuremberg, Cauerstraβe 7, 91058 Erlangen, Germany; Department of Oral and Maxillofacial Surgery, University of Erlangen-Nuremberg, Glückstraβe 11, 91054 Erlangen, Germany
Signal Processing (Impact Factor: 2.24). 01/1997; DOI: 10.1016/S0165-1684(97)00047-9

ABSTRACT Three-dimensional (3D) visualization techniques are becoming an important tool for medical applications. Computer-generated 3D reconstructions of the human skull are used to build stereolithographic models, which can be used to simulate surgery or to create individual implants. Anatomy-based 3D models are used to simulate the physical behaviour of human organs. These 3D models are usually displayed by a polygonal description of their surface, which requires hundreds of thousands of polygons. For interactive applications this large number of polygons is a major obstacle. We have improved an adaptive compression algorithm that significantly reduces the number of triangles required to model complex objects without losing visible detail and have implemented it in our surgery simulation system. We present this algorithm using human skull and skin data and describe the efficiency of this new approach.ZusammenfassungComputerbasierte dreidimensionale Visualisierungstechniken haben im letzten Jahrzehnt Einzug in die Medizin gehalten. Aus den computergenerierten dreidimensionalen Rekonstruktionen des Gesichtsschädels werden unter anderem mittels Stereolithographie reale Modelle erstellt, an denen geplante chirurgische Eingriffe simuliert werden können, oder aber die 3D-Rekonstruktionen dienen dazu, patientenangepaβte Implantate herzustellen. Die Geometrie solch komplexer 3D Modelle wird im allgemeinen mit Hilfe hunderttausender einzelner, planarer Polygone beschrieben. Eine interaktive Darstellung dieser Modelle ist oftmals nicht mehr möglich. In dieser Arbeit beschreiben wir ein erweitertes adaptives Verfahren zur signifikanten Reduzierung von Polygonoberflächen, ohne daβ damit ein Detailverlust in der Darstellung verbunden ist. Dieses Reduzierungsverfahren wurde in ein Operationsplammgssystem integriert und umfassend verifiziert. An zwei medizinischen Datensätzen, der 3D Rekonstruktion der Hautoberfläche und des Gesichtsschädels, wird die Leistungsfähigkeit dieses neuen Verfahrens aufgezeigt.RésuméLes techniques de visualisation tri-dimensionnelle sont en train de devenir un outil important pour les applications médicales. Des reconstructions 3D du squelette humain générées par ordinateur sont utilisées pour construire des modèles stéréolithographiques qui peuvent être utilisés pour simuler une opération chirurgicale ou pour créer des implants individuels. Des modèles tri-dimensionnels basés sur l'anatomie sont utilisés pour simuler le comportement physique d'organes humains. Ces modèles 3D sont en général affichés à l'aide d'une description polygonale de leur surface, ce qui nécessite des centaines de milliers de polygones. Pour les applications interactives, ce grand nombre de polygones est un obstacle majeur. Nous avons amélioré un algorithme de compression adaptatif qui réduit significativement le nombre de triangles requis pour modéliser des objets complexes sans perdre de détails visibles, et nous l'avons implémenté dans notre système de simulation de chirurgie. Nous présentons cet algorithme en utilisant des données de squelette et de peau humains et décrivons l'efficacité de cette nouvelle approche.

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