This paper presents a new approach for providing consistent anatomical structure models based on a geometrical description and on topological features. Volumetric and surfacic techniques are combined to make the best use of the knowledge we have about the object.

The reconstruction process begins with the location of the object in the digital volume. According to the geometrical continuity, active ray tracing in association with geometrical and textural knowledge allows for an efficient interactive investigation.

This investigation gives a rough shape of the object, from which a skeleton is extracted inducing the basis for a geometrical clustering. This clustering makes it possible to get an efficient geometrical characterization of each elementary part of the object.

A first model is then produced, according to the topological information gathered through the previous step. This information makes it possible to extract relevant points from which a triangulated surface can be efficiently reconstructed.

The modeling process is done by turning the triangulated surface into a free-form surface, which is corrected with very local adjustments through a fine texture analysis.