Generation of Surgical Models by Spiral CT and Stereolithography

The use of anatomical models for surgical planning and simulation based on computed tomography (CT) scanning has been proposed early (Alberti 1979). First trials were started in the 1980s (Vannier et al. 1983, Mankovich 1985); they were based on conventional slice-by-slice CT as means for creating the 3D data and on cutting or milling machines to generate the models. The quality of models created by this approach was limited in most cases. The advent of spiral CT scanning which allows to produce 3D data sets with less effort, but with inherently higher 3D spatial resolution and the introduction of layer manufacturing techniques (LMT) which allow to produce anatomical models of arbitrary complexity with very high resolution offered a new basis for these efforts. Here we report on our approach to routinely provide high quality models and on preliminary clinical experience. This effort is partly funded by the European Union as BRITE project PHIDIAS (laser photopolymerisation models based on medical imaging: a development improving the accuracy of surgery). As for other groups (e.g. Brennan et al. 1992, Klein et al. 1992, Kreiborg and Dahl 1993, Fleiter et al. 1994), stereolithography presently is the LMT of highest interest to us.